CN117729957A

CN117729957A - Indwelling cannula

Info

Publication number: CN117729957A
Application number: CN202280050188.3A
Authority: CN
Inventors: 延斯·埃布内特; 维尔纳·施瓦茨
Original assignee: Ebonette Medical Co ltd
Current assignee: Ebonette Medical Co ltd
Priority date: 2021-06-18
Filing date: 2022-06-15
Publication date: 2024-03-19

Abstract

The invention relates to an indwelling cannula (1) for puncturing a hollow body with the aid of a puncture needle, wherein the indwelling cannula (1) has a catheter (2) with a tubular catheter intermediate tube (22) in which the puncture needle can be guided longitudinally displaceably. The indwelling cannula (1) has a manually operable propulsion mechanism (5) by means of which a relative movement between the catheter intermediate tube (22) and the puncture needle can be produced as a result of manual operation, by means of which a puncture tip (31) of the puncture needle protruding from the catheter intermediate tube (22) at the end close to the patient can be accommodated in the catheter intermediate tube (22). Preferably, at least one operating element of the propulsion mechanism (5) is designed as a pivotably mounted lever (53) with at least one lever arm.

Description

Indwelling cannula

Technical Field

The invention relates to an indwelling cannula for puncturing a hollow body by means of a puncture needle, wherein the indwelling cannula has at least one catheter with a tubular catheter intermediate tube, in which the puncture needle can be guided longitudinally displaceably, wherein the catheter is set up for, after puncturing of a sheath of the hollow body to be punctured, pushing over at least a part of the length of the catheter intermediate tube and retaining there for a certain duration through an opening made by means of the puncture needle through the sheath of the hollow body to be punctured. The present invention is described in terms of different embodiments, which may be arbitrarily combined with each other.

Background

1. Description of the embodiments

Indwelling cannula

The invention relates to an indwelling cannula for puncturing a hollow body by means of a puncture needle, wherein the indwelling cannula has at least one catheter with a tubular catheter intermediate tube, in which the puncture needle can be guided longitudinally displaceably, wherein the catheter is set up for, after puncturing of a sheath of the hollow body to be punctured, pushing over at least a part of the length of the catheter intermediate tube and retaining there for a certain duration through an opening made by means of the puncture needle through the sheath of the hollow body to be punctured.

Such an indwelling cannula may be configured as an venous indwelling cannula, for example. The hollow body to be pierced may be a biological hollow body or a hollow body of an object. The hollow body may be, for example, a blood vessel, such as a vein or an artery, as long as the indwelling cannula relates to the medical field.

The terms "puncture" and "perforation" are to be understood herein in a medical sense. "piercing" means piercing a piercing needle into a hollow body such that the piercing needle penetrates the envelope of the hollow body to be pierced.

The portion at the distal (distal) end of the indwelling cannula, and thus disposed near the punctured hollow body, is seen from the user's perspective as a section of the portion of the indwelling cannula near the hollow body. Correspondingly, the section remote from the hollow body is arranged at the end of the indwelling cannula which is proximal from the user's point of view, i.e. further away from the hollow body being penetrated. In connection with the medical application of the indwelling cannula, the terms "proximal to the vein" or "proximal to the patient" or "distal to the user" are also used synonymously with the term "proximal to the hollow body", and for the term "distal to the hollow body" also "distal to the vein" and "distal to the patient" and "proximal to the user" are used.

The parts near the vein tend to be inside the patient and the parts far from the vein tend to be outside the patient. This does not necessarily apply forever, but the term should be further clarified. The supplemental content is self-evident as specified, and the context is decisive.

A puncture-resistant venous indwelling cannula is known from PCT/EP 2019/057097.

An improved puncture system in the sense of a generic puncture system should be produced. In principle, it is also possible with the aid of the improved indwelling cannula to advantageously puncture all body cavities and body spaces to be punctured and all anatomical and pathological structures and to place catheters therein.

In principle, the components of the improved indwelling cannula may also be used in combination with all known puncture and catheter systems, or also as a stand alone product.

Although the term "indwelling cannula" shall be retained hereinafter, it has a broad meaning in the sense of a general puncture system by means of which not only veins can be punctured. That is, in the following, the terms "vein" and "veins" in principle include all blood vessels and more generally all body cavities and body spaces as well as all anatomical and pathological structures that should be penetrated and that should be provided with a catheter.

Thus, by means of the indwelling cannula, the trachea, pleural cavity, abdominal cavity, stomach, intestine, renal pelvis, bladder, structures of the central and peripheral nervous system, subarachnoid space and bones can additionally be penetrated by way of example. Additionally, pathological structures in and on the patient, such as abscesses, may be pierced. Advantageously, arterial blood vessels can also be punctured.

Hereinafter, the term "patient" includes all organisms of all age classes and sexes. Applications in the technical field as well as in and at all objects and structures are equally well feasible, for example in and at reserves, containers, cavities, expandable material and in and at pump systems, hose systems, pipe systems and port systems.

If the word "or" is used in the following, this indicates a possible alternative, but combinations of features or representations separated by "or" are also clearly possible in principle.

All the components described can be used one or more times at the indwelling cannula or also be applied independently of such indwelling cannula at/in other products or completely independently. The different features of the different components may also be combined freely and the features of a particular component may also be used at other components without explicit mention. In principle, all components and features can be applied both inside and outside the patient.

Indwelling cannulas and, in particular, venous indwelling cannulas are specialized medical devices in terms of: the indwelling cannula and especially the venous indwelling cannula must have specific diameter and length dimensions so that it can be administered to the vein at the usual access site in a human or animal patient. For this purpose, a certain flexibility or elasticity of the catheter intermediate tube is also required. Thus, such indwelling cannulas cannot be similar to catheter systems for other applications, such as bladder catheters, because there the completely different requirements apply.

Disclosure of Invention

The invention is based on the object of providing an indwelling cannula which can be applied more simply and safely.

The object is achieved by an indwelling cannula according to claim 1. Advantageous developments are specified in the dependent claims.

According to one advantageous embodiment of the invention, the retaining sleeve has a holding region which is provided for holding the retaining sleeve in the holding region by a user during operation. The holding region of the retention sleeve can here be the following region: there are no other functions or functional elements of the indwelling cannula in said area, but said area is provided only for manual gripping of the indwelling cannula. This has the following advantages: the user intuitively grasps the indwelling cannula at the correct site, thereby avoiding unnecessary touches at other sites, for example, where the indwelling cannula should be forcefully kept sterile. In this way, unnecessary contamination of a specific portion of the indwelling cannula can be avoided. For example, the holding region may be formed at the housing of the catheter, for example, formed in one piece with the housing. The gripping area may be realized, for example, by correspondingly designing an area of the outer surface of the housing.

For example, grooves, bumps or another surface structuring may be present at the grip region. The grip region can likewise be at least partially composed of a material that increases the frictional resistance or can be coated with at least one such material. Thereby preventing undesired slipping of the user's fingers. The gripping area may also be composed of an elastomer, such as rubber or silicone, for example, or of any other material that is softer than the rest of the housing of the indwelling cannula.

The holding region may also be composed of or be coated with at least one antibacterial material. The grip region may likewise have particularly hydrophobic properties. Characteristics in the sense of the lotus effect or similar to the lotus effect are also conceivable.

The grip region may also be designed at least partially in a different color, for example green, than the other components of the venous retention cannula. The area of the venous indwelling cannula which is never allowed to touch may be at least partially red in design. The color "yellow" is also conceivable at least in part in areas where no touching is supposed, but where in special cases it is still possible. This should give the user the idea of the color of the traffic light. However, in particular, strongly luminescent or fluorescent colors are also conceivable.

In a further advantageous embodiment, the entire indwelling cannula is formed transparently, whereby a direct identification of the fluid/blood flow is possible. The puncture needle may also be constructed transparently, as long as the material properties allow it.

Special patterns in the grip area, such as a crisscross or arrow-like pattern, are equally feasible. The areas may also have a number or generally an identification. It is also conceivable that the holding region is first covered by an adhesive structure, for example a film, which can be removed after the puncturing process.

The features described for the grip region may also be implemented at one or more of the grip surfaces described below, alone or in combination.

According to an advantageous embodiment of the invention, the indwelling cannula has a manually operable propulsion mechanism, by means of which a relative movement can be generated between the catheter intermediate tube and the puncture needle as a result of the manual operation, by means of which a puncture tip of the puncture needle, which protrudes from the catheter intermediate tube at the end near the patient, can be accommodated in the catheter intermediate tube. Thus, a number of advantages are achieved as well when applying the indwelling cannula. In conventional indwelling cannulas, the abutment against the patient takes place, for example, at the vein, so that the vein is first penetrated by means of the puncture tip of the puncture needle which protrudes from the catheter intermediate tube. After the venipuncture, the catheter intermediate tube is manually advanced beyond the puncture needle, which can also be pulled back at least partially into the catheter intermediate tube. The steps herein depend on the user's measurements and skills. In this case, errors can occur in the case of inexperienced personnel or in the case of particularly difficult situations, for example by pushing the catheter intermediate tube too far or not so far that a part of the piercing tip still protrudes from the catheter intermediate tube.

By means of the manually operable propulsion mechanism present in the indwelling cannula according to the present invention, a defined operation by the user and correspondingly a defined relative movement between the catheter intermediate tube and the puncture needle is ensured, which is preset by the structure of the indwelling cannula. In particular, by means of the construction of the propulsion mechanism, it is ensured that the puncture tip is completely accommodated in the catheter intermediate tube, so that no further damage is caused when the indwelling cannula is introduced further into the hollow body.

Furthermore, the relatively resilient or flexible catheter intermediate tube is supported, i.e. held, by the puncture needle which is located in the catheter intermediate tube.

The material for the puncture needle may be a metallic material, in particular stainless steel or in principle a metallic alloy. However, the puncture needle may also be composed of a plastic material. The puncture needle can also be constructed in a lightweight manner or from at least one resorbable/readily dissolvable material, such as sugar or salt, in the blood and infusion solution, for example in the region of the puncture tip. Magnesium may also be used. The puncture needle can also advantageously be modified by means of at least one sensor, for example in the region of the puncture tip.

In this case, the configuration of the advancing mechanism ensures that the puncture needle is not pulled back too far into the catheter intermediate tube, so that the catheter intermediate tube can be held over substantially its entire length. In conventional indwelling cannulas, this cannot be achieved due to the fact that the degree of retraction of the needle is determined by the user.

According to an advantageous embodiment of the invention, it is provided that the catheter intermediate tube can be pushed beyond the piercing tip of the piercing needle and/or the piercing tip of the piercing needle can be pulled into the catheter intermediate tube by means of the pushing mechanism. This allows for great flexibility in the construction of the manually operable propulsion mechanism. Thus, optionally, the catheter intermediate tube may be advanced relative to the needle, or the needle may be pulled in relative to the catheter intermediate tube, or a combination thereof.

According to an advantageous embodiment of the invention, it is provided that one, more or all of the actuating elements of the manually operable propulsion mechanism are arranged in and/or form part of the holding area. This has the following advantages: the indwelling cannula can be operated particularly simply by the user and is particularly suitable for one-handed operation during the entire procedure of applying the indwelling cannula to the patient.

The manually operable propulsion mechanism may be wholly or partly, at least with most of its elements, e.g. the manually operable elements, part of the needle device of the indwelling cannula. This has the following advantages: after successful puncture of the vein, which is usually identifiable by the backflow of blood into the puncture needle, the needle device and thus also the puncture needle can be held by the user in a stable, ideally stationary position, and the distal end of the catheter intermediate tube held by the puncture needle can first be advanced precisely beyond the puncture tip into the vein before the catheter intermediate tube is subsequently advanced further into the vein. In this case, the puncture needle is formed together with the mentioned components of the manually operable advancing mechanism as an assembly which can be removed overall from the assembly, in particular the housing, connected to the catheter intermediate tube after the catheter intermediate tube has been correctly placed at the patient, i.e. in the hollow body to be punctured.

The catheter intermediate tube can be applied just via a puncture needle which is held in a position-stable manner. The puncture needle can be pulled back out of the catheter intermediate tube again at any time.

Advantageously, the user always holds the lancet/needle device with his finger.

In the venous indwelling cannula according to the present invention, the needle is controllably pulled back by the user at no time, as determined by the type of construction. This has the following advantages: the user always retains control over the withdrawal of the puncture needle, which makes it possible to achieve an optimal combination of technical control and user-side control.

According to an advantageous embodiment of the invention, it is provided that the relative movement between the catheter intermediate tube and the puncture needle, which can be produced by manual actuation of the advancing mechanism, is limited to a maximum value. This has the following advantages: the operation is particularly simple for the user and the structure of the advancing mechanism ensures that errors are avoided when the catheter intermediate tube is advanced relative to the puncture needle. Limiting the relative movement to a maximum value can be achieved, for example, by means of a force transmission from the actuating element of the propulsion mechanism to the component connected to the catheter intermediate tube. For example, the advancing mechanism can have at least one mechanical stop, by means of which the relative movement between the catheter intermediate tube and the puncture needle, which can be produced by manual actuation, is limited to a maximum value. However, limiting to a maximum value may also be achieved without such mechanical stops.

According to an advantageous embodiment of the invention, it is provided that the maximum value of the relative movement is at least as great as the length of the piercing tip. This ensures that sufficient relative movement is ensured by the advancing means for the complete accommodation of the sharp-edged piercing tip in the catheter intermediate tube.

According to an advantageous embodiment of the invention, it is provided that the maximum value of the relative movement is less than twice the length of the piercing tip. In this way it is ensured that the puncture needle is not pulled back into the catheter intermediate tube unnecessarily far and that sufficient support remains in the sense that the catheter intermediate tube is held by the puncture needle. According to a further advantageous embodiment of the invention, it is provided that the maximum value of the relative movement is less than three times the length of the piercing tip.

The puncturing tip is understood here to be the region of the puncturing needle which is sharpened, for example by means of a beveled edge or a conical contour, which is brought into proximity with the patient. Thus, the length of the piercing tip is the extension of the piercing tip in the longitudinal direction of the piercing needle.

The piercing tip can be designed such that it can penetrate the intact skin of the patient without being pushed in by the user. In a further embodiment, the piercing tip cannot penetrate the skin of the patient or even buckle before penetrating the skin due to its shape without significant advancement. Thus, the piercing tip is less pointed/duller in construction. The invention can thus advantageously be applied directly in very injured/soft anatomical areas, which have been reached through the skin surgically, for example. The invention can be applied, for example, in the region of the central nervous system, in particular in the region of the brain.

Different piercing techniques are possible if the piercing tip has the mentioned oblique edging. In the Bevel-Up technique (level-Up-technique), the piercing tip is introduced through the skin such that the beveled edging, together with the internal opening of the piercing needle present therein, points upwards, i.e. away from the skin of the patient. In the Bevel-Down-technique (Bevel-Technik), the piercing tip is rotated 180 ° relative to the catheter intermediate tube, in contrast, so that the beveled edging, together with the inner opening of the piercing needle present therein, is directed downward, i.e. towards the skin of the patient.

The indwelling cannula may be designed, for example, such that the puncture needle or at least the puncture tip can be rotated about the longitudinal axis relative to the catheter intermediate tube at any time. The user may then selectively apply either a ramp up technique or a ramp down technique. The indwelling cannula can also be designed such that the puncture needle or at least the puncture tip in at least one specific longitudinally displaced position, for example, cannot be rotated or can only be rotated with increased effort relative to the catheter intermediate tube when the puncture tip protrudes from the catheter intermediate tube at the end close to the patient. For example, the assembly with the puncture needle can be positively coupled with the assembly with the catheter intermediate tube in the longitudinally moved position and in this way the rotatability of the puncture needle relative to the catheter intermediate tube is inhibited. The indwelling cannula can be designed, for example, such that the inclined edging, together with the internal opening of the puncture needle present therein, points downwards from the beginning, i.e. towards the skin of the patient or the underside of the indwelling cannula, at which underside at least one fixing wing of the indwelling cannula is provided.

According to a further advantageous embodiment of the invention, it is proposed that the piercing tip rotates about its own longitudinal axis and/or the longitudinal axis of the piercing needle, and can be adjusted here preferably to a circumferential extent of 45 °, 90 °, 135 °, 180 °, 225 °, 270 °, 315 ° or 360 ° (angular specification in degrees with respect to a circumferential extent of 360 °) with all intermediate stages with respect to the circumferential extent being conceivable. In this case, the inclined edging of the piercing tip is already subject to structural decisions that no longer point forcefully upwards, i.e. no longer force away from the patient's skin, before the use of the indwelling cannula according to the present invention. This can advantageously allow for a milder penetration technique, since in particular the penetration/penetration angle can be varied. The puncture needle or the assembly with the puncture needle can have a holding/path limiting element (hereinafter simply referred to as "holding element") by means of which the rotatability/rotatability of the puncture tip/puncture needle is limited or eliminated at least in a specific longitudinally displaced position of the puncture tip and/or puncture needle and/or needle device relative to the catheter intermediate tube. In an advantageous embodiment of the invention, the rotatability/rotatability described above of the puncturing tip/puncturing needle is completely eliminated if the puncturing tip protrudes at least partially distally (toward the patient) out of the catheter intermediate tube. For example, the holding element can be embodied here as a locking element, a cutout, a groove or a projection. The holding element may interact with a holding element at the catheter intermediate tube or other component of the indwelling cannula according to the present invention, for example by latching, wedging or twisting. All holding elements may be at least partially composed of or coated with a friction-increasing material. The above mentioned angular specification is identifiable to the user on the part of the indwelling cannula so that the current circumference at which the puncture tip and/or the puncture needle are placed can be simply read. Circular or semicircular markings of different line widths are also conceivable here, for example, and color markings of the traffic light colors "green", "yellow" and "red", for example, are also conceivable. It is also conceivable to perform an initial penetration and to advance the penetration tip and/or the penetration needle further into the tissue to be penetrated such that the penetration tip and/or the penetration needle are sequentially placed on different circumferences, i.e. rotated/rotated about the longitudinal axis of the penetration tip/penetration needle in the time sequence of the penetration process.

According to an advantageous embodiment of the invention, it is provided that the propulsion mechanism can be fixed in the following manual operating position by means of a locking device: in the manual operating position, the puncture tip is accommodated in the catheter intermediate tube. This has the following advantages: the configuration of the propulsion mechanism prevents the piercing tip from unintentionally re-extending out of the catheter intermediate tube. If the propulsion mechanism is manually operated once and the puncture tip is accommodated in the catheter intermediate tube, it is prevented by the locking means: the puncture tip undesirably again moves away from the catheter intermediate tube.

According to an advantageous embodiment of the invention, it is provided that in a manually actuated position of the advancing mechanism in which the puncture tip is accommodated in the catheter intermediate tube, at least one actuating element of the advancing mechanism can be fixed by means of the locking device and/or at least a part of the housing of the catheter can be fixed on the needle device. This allows a simple implementation of the locking of the propulsion mechanism in the manually operated position. For example, the operating element of the advancing mechanism may be fixed by means of a locking device to another operating element associated as counterpart or to another part of the needle device.

According to an advantageous embodiment of the invention, at least one operating element of the propulsion mechanism is designed as a pivotably mounted lever with at least one lever arm. In this way, a reliably working, robust propulsion mechanism is achieved that can be operated simply and intuitively by the user. For example, the lever may have a force arm and a load arm, wherein the lever is pivotably supported by means of a support element at a position between the force arm and the load arm. The load arm is here a lever arm which applies a force to a component connected to the catheter intermediate tube, for example the housing of the indwelling cannula. The moment arm is a lever arm at which a manipulation force is applied by a user, for example at a gripping surface of the moment arm. The length of the arm and the load arm may be the same or different. For example, the load arm may be longer than the moment arm.

As a control element for generating the advancement of the catheter intermediate tube relative to the puncture needle, there may also be, for example, a rotatably mounted wheel which, when rotated, transmits the propulsion force to the catheter intermediate tube or to a component connected thereto by means of a force-fitting coupling and/or friction. The force-fit coupling between the rotatably mounted wheel and the catheter intermediate tube or the component connected thereto can be provided, for example, by way of a slotted guide or a tooth. Such a rotatably mounted wheel is regarded as a special case of a lever in the following.

The required relative movement between the catheter intermediate tube and the puncture needle, by means of which the puncture tip is finally accommodated in the catheter intermediate tube, can be produced solely by means of manually applied actuating forces. The relative movement can also be supported additionally by the spring force, i.e. by the force of a preloaded spring, by means of which the relative movement manually triggered by the user is guided completely or partly further by the spring force. For example, an indwelling cannula as a manual operating element may have only a triggering element for triggering the relative movement, wherein the relative movement is then further performed by a spring force.

According to one advantageous embodiment of the invention, it is provided that the pushing device as the actuating element has at least two holding surfaces, at which in each case at least one finger of the user can be placed against, wherein the at least two holding surfaces are arranged facing away from one another. This has the following advantages: the user can very simply hold the indwelling cannula and can hold and manipulate it at the same gripping surface during the entire administration procedure at the patient. In this way, one-handed operation is possible without the user having to change the holding position (without surrounding) during the abutment at the patient. By arranging at least two gripping surfaces facing away from each other, the user can enclose them from both sides and thereby safely grip the indwelling cannula.

According to an advantageous embodiment of the invention, it is provided that at least one of the gripping surfaces is arranged on a lever arm of a pivotably mounted lever of the propulsion mechanism. Thereby ensuring safe operation of the propulsion mechanism. The user can intuitively place the finger required for the operation at the correct position.

According to an advantageous embodiment of the invention, it is provided that the lever can be rotated about the axis of rotation, wherein the gripping surface provided on the lever extends from a position further from the puncture needle than the axis of rotation to a position closer to the puncture needle than the axis of rotation, at least in the non-actuated state of the propulsion mechanism. This has the following advantages: avoiding an undesired incorrect manipulation of the propulsion mechanism during the introduction of the piercing tip of the piercing needle into the hollow body. By a corresponding placement of the gripping surface relative to the axis of rotation, sufficient torque is still not transmitted to the lever during the lancing process, so that the propulsion mechanism is not undesirably activated prematurely. In general, it can be said that the axis of rotation should not be arranged too close to the puncture needle, so that a sufficient steering path can be achieved for the advancement of the catheter intermediate tube relative to the puncture needle. For example, the grip surface provided on the lever may be located largely at the arm of the lever, which grip surface may also extend at least over a partial region of the load arm.

According to an advantageous embodiment of the invention, it is provided that the propulsion force for carrying out the propulsion of the catheter intermediate tube relative to the puncture needle is transmitted from the lever to the catheter intermediate tube or to a component connected thereto at the following points: the location is disposed closer to the distal end of the catheter intermediate tube than the rotation axis D about which the lever is pivotally supported.

According to an advantageous embodiment of the invention, it is proposed that the puncture needle is formed as an assembly with the manually operable pushing mechanism, the components of the assembly being firmly connected to one another, for example, such that the components cannot be disconnected from one another without tools. In particular, the pivotably mounted lever may be formed as a fixed component of the assembly comprising the advancing mechanism and the puncture needle. If the puncture needle should be removed after performing the puncture on the blood vessel, the entire assembly, i.e. the puncture needle together with the propulsion mechanism comprising the lever, is always removed in this way.

According to an advantageous embodiment of the invention, it is provided that the lever can be pivoted steplessly from an initial position in which the tip of the puncture needle protrudes completely from the catheter intermediate tube into a final position in which the puncture needle is completely accommodated in the catheter intermediate tube. This allows for very sensitive operation of the venous indwelling cannula when administered to a patient.

According to an advantageous embodiment of the invention, it is provided that the pushing mechanism has at least one securing element, by means of which the pushing mechanism is prevented from being operated until the securing element is disengaged. For example, the securing element may be designed such that the pivotable lever cannot be pivoted yet initially, i.e. in the secured state. The stability is only eliminated by targeted actuation of the unlocking element and the lever can be pivoted. Thereby providing stability against inadvertent advancement of the catheter intermediate tube relative to the needle. For example, the securing element may be unlocked such that a particular component of the propulsion mechanism must first be actuated in a particular direction, in particular in a different direction than the lever is actuated for pivoting. For example, in order to unlock the stabilizing element, the lever may first have to be pressed down towards the puncture needle, or first the parts of the lever have to be pressed together laterally in order to eliminate the stabilization.

According to an advantageous embodiment of the invention, it is provided that the indwelling cannula, in particular the catheter intermediate tube thereof, has one or more markers by means of which a relative movement between the catheter intermediate tube and the puncture needle due to a manual actuation of the advancing mechanism can be displayed. In this way, the user can optically check in a simple manner: whether sufficient relative movement is performed between the catheter intermediate tube and the needle. In particular, the current position generated by the propulsion mechanism can be optically read.

According to an advantageous embodiment of the invention, it is provided that the propulsion mechanism has at least one intermediate position between its end positions, which is tactilely detectable by the user, for example in the form of a locking position. In this way, the intermediate position or positions of the generated relative movement of the puncture needle with respect to the catheter intermediate tube can be preset structurally and can be set actively by the user. By means of a tactile check, the user can easily identify which intermediate position the propulsion mechanism has reached, for example in that an increased resistance occurs in the respective intermediate position when the propulsion mechanism is actuated. In this way, the stiffness of the catheter intermediate tube can be varied and can be adapted to the individual anatomy. In the case of fragile blood vessels, it may therefore be advantageous for the catheter intermediate tube to be constructed more flexibly already when introduced into the blood vessel, in particular in the region close to the patient, in order to ensure a more gentle introduction into the blood vessel.

One feature of conventional iv cannulas is the unrestricted longitudinal mobility of the internally located needle relative to the externally located catheter intermediate tube, as determined by the configuration. Thus, the puncture needle can be pulled back/out of the catheter intermediate tube towards the user for removal after a successful puncture, depending on the function. However, a fairly flexible catheter intermediate tube is often required to remain when advanced into the vein after a successful puncture, whereby the catheter intermediate tube can be stably advanced into the vein. The holding is achieved by means of an internally located puncture needle. However, in the conventional venous indwelling cannula, the extent of retraction of the puncture needle is uncertain. In the event of too small a pull back, the tip of the needle may still be exposed at the end of the catheter intermediate tube near the vein, undesirably damaging the anatomy. In the event of excessive pullback, the catheter intermediate tube may not be adequately retained when advanced into the vein. However, the puncture needle may also be undesirably advanced again toward the vein after being pulled back. This may cause damage to the catheter intermediate tube caused by the tip of the puncture needle, thereby for example also causing a portion of the catheter intermediate tube to shear into the vein.

In the indwelling cannula according to the present invention, the puncture needle is pulled back in the longitudinal direction after successful venipuncture by a defined path segment into the catheter intermediate tube. This has the following advantages: the user can ensure that the tip of the needle no longer protrudes in the longitudinal direction out of the catheter intermediate tube towards the vein. In this state, the tip is completely surrounded by the outer catheter intermediate tube, so that undesired damage to the anatomical structure is avoided.

However, in the indwelling cannula according to the present invention too, it is avoided that the puncture needle is pulled back into the catheter intermediate tube too far away from the vein during the puncture procedure, so that the intermediate tube is not adequately held. Thus, the needle retains the catheter intermediate tube on a precisely defined path segment and stabilizes it precisely as it is advanced into the vein. In addition, the path segments may be displayed by markers at the indwelling cannula. The path section can also be changed precisely by the user in that corresponding grooves/recesses are provided on the indwelling cannula, into which grooves/recesses, for example, the gripping element can be locked.

Advantageously, a maximum value of the relative movement between the catheter intermediate tube and the puncture needle can be preset, which can be overcome by the user only with special effort, so that the puncture needle can be removed. This prevents the needle from undesirably sliding completely out of the indwelling cannula. This is particularly important if the catheter intermediate tube is very flexible and/or has, for example, also a spiral-shaped or wave-shaped structure, as may be the case in an indwelling cannula according to the present invention.

This can also be particularly important if the indwelling cannula is formed very flexibly only at the transition between the catheter intermediate tubes and/or only in a portion remote from the vein, for example at the skin level, as just described.

In particular, if the catheter intermediate tube is additionally constructed in a puncture-proof manner, there is a maximum safety against undesired injuries of the anatomical structure through the tip of the puncture needle.

The pronounced thermoplasticity of the catheter intermediate tube is no longer imperative, since it can be constructed very flexibly and the stiffness normally required for advancement into the vein is ensured mainly by the puncture needle.

It is also contemplated that the needle must first be advanced into a position in which the tip of the needle protrudes toward the vein out of the catheter intermediate tube for penetration.

The indwelling cannula may also be fixed to the skin by means of a wire at the concave ridge (see figure), especially when the ridge has grooves/recesses/protrusions, lateral hollows and/or other fastening elements.

Furthermore, the indwelling cannula according to the present invention is better operable with one hand than conventional indwelling cannulas. The other hand of the user can thus be used, for example, to stabilize the body part to be penetrated and to tighten the skin. This increases the probability of successful puncture.

In contrast to conventional indwelling cannulas, there may also be defined and intuitively operable gripping surfaces for the fingers of the user in an indwelling cannula according to the present invention. The indwelling cannula is thus no longer undesirably soiled/contaminated, in particular in the area of the access site into the skin and/or in the area of the bearing surface to the skin. Furthermore, the access area into the skin is particularly protected from soiling/contamination, as determined by the structure. The grip surface itself is adapted to the anatomy of the user and may also be designed to be kneadable/deformable.

The fastening of the indwelling cannula according to the present invention is additionally simplified, since the fastening wings are connected to the other parts of the indwelling cannula only via the narrow tabs, so that for example a band-aid can be placed in a simplified manner. In particular, the wings and/or strips of the band-aid may simply pass under the indwelling cannula. It is also conceivable that the wings are pivotably arranged at the indwelling cannula. It is also conceivable that the wings are designed to be kneadable and/or deformable, so that irregularities in the skin region of the patient can also be optimally matched. It is also possible for the webs to be composed of at least one kneadable and/or deformable and/or elastic material. Advantageously, the webs can also be improved by means of at least one spiral-shaped and/or spring-shaped structure. Thus, if the tab as just described is between the loaded component and the other component, the effect of the force/motion acting on the loaded component of the venous indwelling cannula on the other component of the venous indwelling cannula can be reduced, e.g. buffered.

Any conventional/commercially available single lumen or multiple lumen catheter intermediate tube may be used. According to an advantageous embodiment of the invention, however, the intermediate conduit pipe has at least one support structure by means of which the bending moment and/or the radial moment of resistance of the intermediate conduit pipe can be increased. The support structure may be constructed in the form of one or more reinforcing elements.

For example, the support structure may be a spiral-shaped structure extending over a certain longitudinal section of the catheter intermediate tube, which may be integrated at the inner side and/or the outer side of the catheter intermediate tube and/or partially or completely into the catheter intermediate tube wall. There may also be a plurality of such support structures coaxial. The spiral-shaped structure may also have spring-like properties. Instead of a spiral structure, it is also possible to have individual support rings spaced apart from one another, not only integrated on the inside, outside and/or completely or partially integrated into the catheter intermediate wall. The spiral-shaped structure and/or the ring may be formed from a circular material or a flat material, in particular from a metallic material. The at least one support structure may also be formed by a thin-walled support sleeve or a support braid of fibers interwoven with one another or of fibers bonded into a woven or woven fabric. The central tube of the catheter can be formed in one or more layers in the radial direction, with each radial layer being composed of the same material but also of different materials. For example, the support structure may be embedded in an inner radial layer covered by an outer radial layer of the catheter intermediate tube.

As a material for the catheter intermediate tube, for example, polyurethane (PU) or FEP is considered. The material for the support structure may be a metallic material, in particular stainless steel and/or a metallic alloy, in particular nitinol. Nitinol has the following advantages: the desired resistance of the catheter intermediate tube against pressing together or bending is further enhanced by the memory effect.

Other materials for the support structure may be plastic materials, in particular also fibre-reinforced plastics, such as carbon fibre or aramid fibre-reinforced plastics.

In the spiral design of the support structure, there may be one spiral or a plurality of spirals placed in each other. The coils of the spiral may have the same pitch or a varying pitch from each other over the entire length of the support structure. In an advantageous embodiment of the invention, the helical support structure can have a smaller spacing of the coils from one another in the region remote from the hollow body than in the region close to the hollow body.

Other structures that stabilize the support structure may exist between the coils. In an advantageous embodiment, the structure is tensioned, i.e. becomes more rigid, when the coils are moved away from each other. The structure between the coils also ensures that the coils can only be spaced apart from each other to a limited extent. As the coils move towards each other, the structure between the coils becomes less rigid. In this embodiment, the support structure has an accordion-like structure.

In an advantageous embodiment, the structure between the coils can be such that the support structure is at least partially fluid-impermeable with the corresponding material selection.

With such a support structure, the visibility of the catheter in the patient can be improved by means of the imaging medical method, for example by ultrasound examination, when using materials, in particular metallic materials, which are visible in the imaging medical method. In an advantageous embodiment of the invention, the support structure or a series of several support structures present in the longitudinal direction are unevenly designed in the longitudinal extension. By means of the non-uniform design, a still more accurate identification of the position of a specific region of the catheter in the patient can be achieved by means of the imaging medical method.

According to an advantageous embodiment of the invention, the central tube of the catheter has a plurality of lateral through openings extending from the inner side to the outer side. The through opening (side hole) may be present over the entire length of the catheter intermediate tube, or may be present only on one or more longitudinal sections, for example in a section closer to the hollow body. The through openings may be arranged distributed over the circumference of the catheter intermediate tube. The flow of liquid through the intermediate tube of the catheter can be improved by the through openings in the intermediate tube wall of the catheter.

According to an advantageous embodiment of the invention, one, several or all of the through openings are provided in the region of the intermediate tube of the catheter which is not covered by the support structure. For example, if the support structure has a spiral shape, through holes may be provided between the coils of the spiral. In this way, the flow through the through opening is not impeded by the support structure.

It is also conceivable that the helical support structure is not surrounded and/or coated with a fluid-impermeable material at least over a part of the length of the catheter intermediate tube. Thus, the indwelling cannula may be penetrable for liquids in said area even without through holes. In an advantageous embodiment, the coils of the helical support structure have a greater distance from one another in the region than in the other region of the catheter intermediate tube. The region may preferably be adjacent to the hollow body as described hereinabove.

It is also conceivable that the fluid-impermeable material surrounding and/or coating the spiral-shaped support structure has a gap and/or a discontinuity at least over part of its length, so that the fluid-penetrability of the indwelling cannula in the region of said gap/discontinuity is ensured. Then the side holes are no longer mandatory.

The indwelling cannula according to the present invention has the following advantages: the just mentioned liquid-penetrable sites, for example side holes, are provided only in the following areas of the catheter intermediate tube: the region is held by the needle during the lancing process and is thus also sealed from the inside. Thus, during the puncturing procedure, foreign bodies and/or also, for example, flushed skin components do not block the side holes and/or are not undesirably carried into deeper anatomical structures in the side holes.

However, in the indwelling cannula according to the present invention, it is also advantageously possible to precisely and selectively release a liquid-penetrable site, such as a side hole, by means of a different position of the puncture needle in the longitudinal direction if said site is at or at a different position in the longitudinal direction. Thus a precisely controlled dilution effect can be produced, for example in order to more gently infuse the venous-stimulating substance.

In a further advantageous embodiment, the material may also only partially surround the helical support structure in communication in the longitudinal direction of the indwelling cannula. Thus, a tab may be formed which counteracts the unwinding of the support structure. In the case of very tightly wound, the support structure may be constructed fluid-impermeable, but in the case of less tightly wound, it may also be constructed fluid-permeable. It is also possible to determine by the density of the windings whether the support structure is constructed fluid-impermeable but still permeable to gas/vapour. It is also conceivable that the support structure is permeable only to certain fluids. It is also conceivable that the support structure has thermoplastic properties and/or is expanded by body heat.

According to an advantageous embodiment of the invention, the guide tube has a housing, at which the guide tube intermediate tube is arranged. The catheter intermediate tube continues from the side of the housing directed toward the hollow body. According to one advantageous embodiment of the invention, the guide tube has a bend protection in the region in which the guide tube intermediate tube protrudes from the housing, i.e. in the intermediate tube exit region of the housing, which completely or at least partially surrounds the guide tube intermediate tube on the circumferential side, by means of which the risk of bending the guide tube intermediate tube in the region of the exit point from the housing is reduced. In this way, undesired bending of the catheter intermediate tube during operation of the indwelling cannula, in particular in the region of the exit point from the housing, can be avoided. This region is particularly vulnerable to kinking, since in the known venous indwelling cannulas, a sudden transition from a relatively robust, inflexible housing into a comparatively thin-walled and correspondingly sensitive catheter intermediate tube occurs. By means of the fold protection structure according to the invention, the abrupt transition in the region has been designed more gradually. For example, the bend protection structure may comprise a flared rounded surface surrounding the catheter intermediate tube at the circumferential side.

In an advantageous embodiment of the invention, the holding region is designed such that it has two holding surfaces which are arranged on opposite sides of the component on which the holding region is present. This has the following advantages: the retention sleeve can be held well at the holding area with the thumb and another finger, for example the middle finger or the index finger, in a simple and safe manner. In particular, the gripping surface may be a substantially flat gripping surface or have at least a substantially flat portion. In the flat region of the gripping surfaces, the gripping surfaces may be arranged parallel to one another. The gripping surface may also be configured in a manner of a cavity having an at least partially curved (concave) surface. The gripping surface may have a structuring by means of which the indwelling cannula may be gripped still better and slipping of the fingers is avoided.

For example, grooves, bumps or another surface structuring may be present at the grip surface. In particular, the gripping surface may be designed such that its dimension in the longitudinal direction of the indwelling cannula is larger than the dimension in the transverse direction, for example at least twice as large as the dimension in the transverse direction. The respective holding surface can be composed of the material of the housing of the indwelling cannula or of another material, in particular a material with greater elasticity or flexibility. For example, the gripping surface may be configured as an insert, for example, composed of an elastomer, such as rubber or silicone, or of any other material that is softer than the material of the housing of the indwelling cannula. Such an insert part can then be fastened in a corresponding recess of the housing of the retention sleeve.

According to an advantageous embodiment of the invention, the indwelling cannula has at least one finger stop device at the housing, which is arranged at or near the intermediate tube exit region. Whereby the finger stop device is significantly spaced from the proximal end of the housing. The finger stop device is used to avoid that the fingers of a user with which the user holds the indwelling cannula unintentionally slip off the housing, i.e. towards the patient, in the longitudinal direction of the indwelling cannula when applied to the patient. Thereby, the finger stop device forms an obstacle for the finger to slip off the housing relative to the patient. Contamination of the components of the puncture site at the patient and of the indwelling cannula in the region of the puncture site is avoided in this way. For example, the finger stop device may be configured as a circumferential enlargement, for example in the form of a rim, bulge or other thickening, relative to an adjacent circumferential region of the housing. The finger stop device may completely surround the housing on the circumferential side, or may surround the housing only in part of the sections, for example only laterally to the left and right of the catheter middle tube.

Drawings

The invention is described in more detail hereinafter with reference to the accompanying drawings according to embodiments. The drawings show:

Figure 1 shows an indwelling cannula according to an exploded view,

figure 2 shows the indwelling cannula in a perspective view,

figures 3 and 4 show the indwelling cannula according to figure 2 in a side view in partial section,

figure 5 shows in a view on the bottom side an indwelling cannula according to figure 2,

figures 6-8 show the indwelling cannula according to figure 2 in different use conditions,

figure 9 shows in perspective view an indwelling cannula in another embodiment,

figure 10 shows in side view the indwelling cannula according to figure 9,

figures 11 and 12 show in side view in partial section an indwelling cannula according to figure 9,

figure 13 shows the indwelling cannula according to figure 9 in use,

figure 14 shows in perspective view an indwelling cannula in another embodiment,

figures 15, 16 show in top view the indwelling cannula according to figure 14 in different use conditions,

figure 17 shows in perspective view an indwelling cannula in another embodiment,

fig. 18, 19 show the indwelling cannula according to fig. 17 in side views in different use states.

Detailed Description

The indwelling cannula 1 shown in fig. 1 according to an exploded view has a catheter 2 and a needle device 3. The catheter 2 has a housing 20 at the patient-facing side of which there is an intermediate tube exit region 21, at which a catheter intermediate tube 22 exits from the housing 20 and protrudes therefrom. The catheter intermediate tube 22 is comparatively flexible and serves as an administration possibility for intravenous introduction of liquids, in particular infusion solutions, blood products and medicaments. The catheter intermediate tube 22 is then with its distal end portion in a hollow body, for example a vein of a patient. The needle device 3 has a puncture needle 30 which, in the basic state of the indwelling cannula 1, is largely in the housing 20 and the catheter intermediate tube 22, wherein the tip 31 of the puncture needle 30 protrudes from the distal end of the catheter intermediate tube 22. The needle device 3 is movable in the longitudinal direction L relative to the catheter 2.

At the housing 20, fixing wings 23 are provided, which serve for manual operation and for securing the catheter 2 at the patient. On the side facing away from the intermediate tube exit region 21, the housing 20 has a needle opening 25 through which the puncture needle 30 can be placed in the housing 20 and the catheter intermediate tube 22. After the indwelling cannula has been placed against the patient, the needle device 3 is removed. The needle opening 25 is then used as a connection possibility for an infusion line or an extraction element, such as a syringe.

There may also be injection ports at the housing 20, which for example protrude from the housing 20 on the side facing away from the fixing wing 23. The injection port is used for injecting a drug. Otherwise the injection port is closed by means of a closing cap.

Furthermore, the needle device 3 has a closure element 33 with a plug and an operating element 32 at the proximal end of the puncture needle 30. In the basic state, the needle opening 25 is closed by the closing element 33. The operating element 32 is used for operating the needle device 3 by a user, i.e. essentially for pulling back the puncture needle 30 after the puncture is completed. As mentioned, the needle device 3 is removed after the catheter 2 is brought to rest against the patient.

The needle device 3 may have a connection port 34 at the proximal end, i.e. in the region of the operating element 32, for connecting a syringe or infusion line, for example for drawing blood. The connection port 34 is closed by the closing cap 4. For example, the closure cap 4 can be screwed or plugged in.

Fig. 2 to 5 show an indwelling cannula 1 with a manually operable propulsion mechanism 5 for generating a relative movement between the catheter intermediate tube 22 and the puncture needle 30. In the illustrated embodiment, the propulsion mechanism 5 has a base body 51 which is fastened to the housing or to another part of the needle device 3, for example at or near the closing element 33. A pivotably mounted lever 53 is connected to the base body 51 via a hinge 52, said lever forming an actuating element of the manually operable propulsion mechanism 5. The lever 53 is pivotably connected to the base body 51 via a hinge 52. For example, the hinge 52 can be formed as a material bridge, i.e. in the form of a material-fitting connection, between the lever 53 and the base body 51. In this way, the assembly formed by the base body 51, the hinge 52 and the lever 53 can be manufactured as a one-piece assembly. The hinge 52 can form a rotational axis about which the lever 53 is pivotally or rotatably mounted.

At the base body 51 there is a gripping surface 50 against which the fingers of the user rest. At the lever 53 there is a gripping surface 54, for example in the form of a concave cavity with corrugations. The gripping surfaces 50, 54 are provided at the sides of the respective components facing away from each other, so that they can be gripped, for example, between the thumb and index finger of a user. The middle finger of the user can rest against the underside of the base body 51, as is also shown below in fig. 6 and 7. For example, the gripping surfaces 50, 54 may be grooved in the lateral direction. In order to provide increased accommodation for the fingers of the user in the region of the front gripping surface 54, the housing 20 can have a tapering or otherwise designed recess 70 in front of the gripping surface 54 into which the fingers of the user can extend at least partially when the lever 53 is actuated.

At the housing 20 of the catheter 2 or at the part connected thereto, a housing edge or a further element is provided, for example a laterally projecting pin 57 as shown in the figures, via which an actuating force applied at the gripping surface 54 can be transmitted to the catheter 2 by means of the lever 53 in order to generate a relative movement between the catheter intermediate tube 22 and the puncture needle 30. For example, the pin 57 or another edge may be molded in one piece at the housing 20. A corresponding pin receptacle for receiving the pin 57, which surrounds the pin 57 in the non-actuated state of the advancing mechanism 5, can be provided, for example molded, on the lever 53, so that the manual advancing of the catheter intermediate tube 22 beyond the puncture needle 30 is thereby blocked. The pin 57 is released after the lever 53 is actuated as shown in fig. 4, so that the desired advancement of the catheter intermediate tube 22 relative to the puncture needle 30 is possible.

In fig. 3, an indwelling cannula 1 with a propulsion mechanism 5 that has not yet been manipulated is shown. Correspondingly, the piercing tip 31 protrudes from the catheter intermediate tube 22. Fig. 4 shows an indwelling cannula 1 with a manipulated propulsion mechanism 5. Correspondingly, the piercing tip 31 is accommodated in the catheter intermediate tube 22.

In order to lock the propulsion mechanism 5 in the manually operated position, one or more locking means may be present. Illustratively, a locking edge 56, for example an edge in a groove, is formed on the base body 51, which edge interacts with a locking hook 55 provided on the lever 53. As in the manually operated position shown in fig. 4, the locking hooks 55 lock behind the locking edge 56, so that the manually operated position is not undesirably changed again, in which position the puncture tip 31 is accommodated in the catheter intermediate tube 22.

As is evident in particular from the partial sectional views of fig. 3 and 4, additional locking means can be present between the base body 51 and the catheter assembly 2. Thus, a first locking element 58, for example in the form of a U-shaped release locking tongue, can be formed at the base body 51, which locking tongue can be locked with a locking edge 29, which can be formed at the patient-remote side of the housing 20, in the manually operated position. This additionally prevents undesired rearward movement of the catheter intermediate tube 22 relative to the puncture needle 30.

The at least one locking device can be designed such that an acoustic signal, for example a click, is generated when the propulsion mechanism 5 is manually actuated and the corresponding locking is effected. In this way, acoustic feedback can be given to the user about the complete manipulation of the propulsion mechanism 5.

In addition, the housing 20 has two protective projections 42 extending continuously in the distal direction from the left and right sides of the catheter intermediate tube 22. A protective projection 42 protrudes from the housing 20 at the intermediate tube exit region 21. Between the protection projections 42, guide slits 43 are provided above and below the catheter intermediate tube 22, respectively. In particular, the lower guide slit 43 can realize that the catheter intermediate tube 22 can extend with a gentle curvature towards the patient in the state of abutment against the patient, i.e. the guide slit 43 provides room for a defined curvature of the catheter intermediate tube 22 and prevents bending or breaking of the catheter intermediate tube 22. The catheter intermediate tube 22 is additionally laterally protected in this region by a protection projection 42. A protective cover receptacle can be formed at the protective projection 42, for example in the form of a recess extending into the protective projection 42. In this manner, the protective cover can be inserted over the needle tip 31 and the catheter intermediate tube 22 and secured at the housing 20.

Additional gripping surfaces at the housing 20 may extend toward the distal end into the region of the protective projection 42. Advantageously, a finger stop device is provided at the distal end of the housing 20 or the protective projection 42, for example in the form of a thickening, for example a bulge or a rim. This prevents the user from slipping out of the housing 20 or the grip surface with his fingers forward towards the patient 5, for example, when the indwelling cannula is placed against the patient.

Other gripping surfaces can also be formed laterally on the base body 51. The gripping surfaces can each be arranged laterally so that the base body 51 can no longer be "seen" from the side. Intuitively, the gripping surface may be gripped, for example, with a right thumb (on the left) and a right middle finger (on the right), wherein the right index finger may then operate lever 53. Corresponding embodiments are also described below with reference to fig. 9 to 13.

Furthermore, the indwelling cannula 1 according to fig. 2 to 5 may be configured as the indwelling cannula 1 according to fig. 1.

Fig. 6 to 8 show the practical application of the indwelling cannula 1 by a user, wherein only one hand 6 is shown. In fig. 6, the indwelling cannula 1 is in an initial state in which the puncture tip 31 protrudes from the catheter intermediate tube 22. In this state, as in the conventional indwelling cannula, piercing is performed on the hollow body to be pierced. If a puncture is performed, i.e. the puncture tip 31 is in the hollow body together with the end of the catheter intermediate tube 22 close to the patient, a manual manipulation of the propulsion mechanism 5 shown in fig. 7 can be performed. For this purpose, the force is transmitted via the holding surface 54 to the lever 53, wherein the hand 6 can be supported, for example, via a thumb, on the opposite holding surface 50. As can be seen in fig. 7, the puncture tip 31 is now accommodated in the catheter intermediate tube 22. Here, the puncture needle 30 remains fixed in position when the pushing mechanism 5 is operated.

The indwelling cannula 1 can be advantageously held and operated in one hand, for example, by placing the thumb of the hand 6 against the holding surface 50, the index finger against the holding surface 54, and optionally additionally for support, another finger, for example the middle finger, against the underside of the base body 51.

After the relative movement produced by the advancing mechanism 5 has been carried out, the catheter intermediate tube 22, which is held at least over its entire length by the inner puncture needle 30, can now be pushed further into the hollow body until the desired position has been reached. Thereafter, as in a conventional indwelling cannula, the needle device 3 is removed from the catheter 2, wherein it can be seen in fig. 8, whereby the pushing mechanism 5 is also removed.

In the embodiment described so far, the propulsion mechanism 5 is designed to open laterally opposite in the region of the gripping surface 50. However, the sections can also be designed to be laterally closed, for example by side walls. Additional lateral holding surfaces can be present in the region of the side walls.

A variant of the propulsion mechanism 5 is described in terms of the embodiment of the indwelling cannula according to fig. 9 to 13, which has a pivotable lever 53 similar to the previously described embodiment. However, the lever is arranged in the base body 51 which is at least laterally largely closed and is supported on the rotation axis D. The base body 51 encloses the lever 53 at least laterally and partially also at the rear, so that the lever 53 is largely covered with respect to the surroundings and the grip surface 54, which is mainly used for manual actuation, is external. In particular, a locking mechanism with a locking hook 55 and a locking edge 56 may be provided in the area enclosed by the base part 51. In this way, the components of the propulsion mechanism 5 and the needle opening 25 are also better protected from contamination. Furthermore, it is prevented that parts of the user's glove, for example, may be blocked in the region of the locking elements 55, 56.

As can be seen in fig. 9, the grip surface 54 extends from a position below the rotation axis D, i.e., a position disposed closer to the puncture needle 30 than the rotation axis D, toward a position disposed above the rotation axis D, as viewed from the puncture needle 30.

The operation of the indwelling cannula 1 and its pushing mechanism 5 when administered to a patient can also be improved in the illustrated variant by: lateral gripping surfaces 71 are provided at both sides of the base part 51. Additionally, a lower grip surface 72 may also be present on the underside of the base body 51, i.e. on the side facing the patient. The lateral holding surface 71 and/or the lower holding surface 72 can likewise have a corresponding structuring as already described for the holding surfaces 50, 54.

The base body 51, to which the lever 53 is fastened, can be formed as a one-piece construction unit with the housing or the closing element 33 of the needle device 3, for example as a plastic injection-molded component.

For example, the base body 51 can be designed as a largely closed housing which accommodates the lever 53. For example, the base body 51 may have at least two opposing side walls, a lower wall, and a rear wall toward the proximal end. Then, the side of the base body 51 that is open toward the distal end can be largely closed by the lever 53.

The lever 53 may have a rear wall at a side facing the base body 51, which rear wall has a circular curved profile at least at the outer side. The rear wall of the base body 51 facing the circularly curved contour of the lever 53, for example the rear wall with the grip surface 50, can have a contour complementary thereto, i.e. a likewise circularly curved contour, at least at the inner face facing the curved contour of the lever 53. The circular curved contour may be arranged concentrically to the axis of rotation of the lever 53. In this way, it can be said that the lever 53 is formed nested with the base body 51 formed as a housing, which results in particularly good protection against contamination. Additionally, the lever 53 may have a sidewall that is disposed parallel to the sidewall of the base body 51 and at least partially overlaps the sidewall of the base body 51. In this way, the arrangement of the base body 51 and the lever 53 also forms good pollution protection in the lateral direction.

The lever 53 can be rotatably mounted on the base body 51 via its axis of rotation D. For example, for the design of the rotary support, a respective pin can be formed at one of the component lever 53 and the base body 51, which pin engages in a recess at the respective other component.

Fig. 9 shows the propulsion mechanism 5 in an unactuated position. Fig. 10 shows the propulsion mechanism 5 in the manoeuvred position.

Similarly, fig. 11 shows propulsion mechanism 5 in the non-actuated position, and fig. 12 shows propulsion mechanism 5 in the actuated position. It can be seen that the locking elements 55, 56 are arranged in the region enclosed by the base body 51, so that they can be protected from environmental influences and are tamper-proof. In fig. 12, the locking hooks 55 are locked with the locking edges 56.

Due to the various gripping surfaces, there are a number of possibilities for the user to hold and manipulate the indwelling cannula 1. Fig. 13 shows an advantageous variant of the operation, in which the indwelling cannula 1 is operated with three fingers, for example so that the user holds the indwelling cannula 1 with the thumb and middle finger at opposite lateral holding surfaces 71 and places the index finger at the holding surface 54 of the lever 53. In this way, the hollow body can be pierced first by means of the piercing tip 31 and then the propulsion mechanism 5 can be maneuvered with the index finger via the gripping surface 54 without having to change the position of the hand 6.

Fig. 14 to 16 show an indwelling cannula 1 of alternative design with a manually operable propulsion mechanism 5. In the illustrated embodiment, the propulsion mechanism 5 is designed in the form of a clamp, which has two clamp arms 59 opposite one another, a part of the housing 20 of the catheter 2 extending in front of said clamp arms. Here, there are also gripping surfaces 50, 54 which again face away from one another, in which case they are formed on the outside of the gripper arms 59. The gripper arms 59 are firmly connected to the needle device 3 at one side and engage into corresponding recesses in the housing 20 at the other side, i.e. at the opposite free end, wherein the gripper arms are supported on the housing edge 28 and, as shown in fig. 14, ensure the advancement of the catheter 2 and thus the catheter intermediate tube 22 relative to the needle device 3 via said housing edge 28 upon manual manipulation.

In fig. 15, an indwelling cannula 1 with a propulsion mechanism 5 that has not yet been manipulated is shown. Correspondingly, the piercing tip 31 protrudes from the catheter intermediate tube 22. Fig. 16 shows an indwelling cannula 1 with a manipulated propulsion mechanism 5. Correspondingly, the piercing tip 31 is accommodated in the catheter intermediate tube 22. Manipulation is performed by applying a manipulation force F towards each other to the grip surfaces 50, 54, for example by means of the thumb and index finger of one hand.

In order to lock the advancing mechanism 5 in the manually actuated position in which the piercing tip 31 is accommodated in the catheter intermediate tube 22, a locking arm 58 can be present, for example, at the needle device 3, for example in the region where the forceps arm 59 is connected to the housing of the needle device 3, which locking arm interacts in a locking manner with a locking edge 29 formed at the housing 20.

Fig. 17 to 19 show an indwelling cannula 1 with an alternative embodiment of the propulsion mechanism 5. In this case, the propulsion mechanism 5 has a basic body 51 which is fastened to a component of the needle device 3, similarly to the previously described embodiments. The base body 51 extends towards a pressure arm 60 via which pressure can be applied to the housing 20 of the catheter 2. For manual operation, a gripping surface 50 is provided on the underside of the base body 51, and, in contrast, a gripping surface 54 is provided on the push arm 60. The user then grips the indwelling cannula 1 between the gripping surfaces 50, 54 with two fingers, such as a thumb and forefinger.

If the desired relative movement between the catheter intermediate tube 22 and the puncture needle 30 should be produced by the advancing mechanism 5, it is pressed from above via the grip surface 54 with a force F onto the pressure arm 60. The pressure arm then transmits the force to a thrust surface 27 embodied as an inclined plane, which is embodied at the housing 20. The thrust surface 27 does not have to be planar, but may also be curved. As shown in fig. 19, the catheter intermediate tube 22 is advanced relative to the puncture needle 30 by a force F applied to the advancing surface 27 from above via the pressing arm 60, so that the puncture tip 31 is accommodated in the catheter intermediate tube 22.

In fig. 18, an indwelling cannula 1 with a propulsion mechanism 5 that has not yet been manipulated is shown. Correspondingly, the piercing tip 31 protrudes from the catheter intermediate tube 22. In fig. 19, an indwelling cannula 1 with a steerable propulsion mechanism 5 is shown. Correspondingly, the piercing tip 31 is accommodated in the catheter intermediate tube 22.

In order to lock the propulsion mechanism 5 in the manual actuation position, a locking arm 58 is again present at the base body 51, which locking arm locks behind the locking edge 29 provided at the housing 20 in the manual actuation position.

2. Description of the embodiments

Indwelling cannula

Thus, with the aid of the indwelling cannula, the trachea, pleural cavity, abdominal cavity, stomach, intestine, renal pelvis, bladder, subarachnoid space and bone may additionally be penetrated by way of example. Additionally, pathological structures in and on the patient, such as abscesses, may be pierced. Advantageously, arterial blood vessels can also be punctured.

Table 1 below gives an overview of the currently common variants of venous indwelling cannulas mainly used in the field of human medicine.

Size: the outer diameter, inner diameter, wall thickness and length relate to the catheter intermediate tube. In the "bandwidth" line it is possible to specify which tolerance ranges in the respective specification.

As can be seen, the catheter intermediate tube has a relatively small diameter dimension and, correspondingly, also a very small wall thickness. Common catheter intermediate tubes are manufactured from a uniform extruded plastic material. In the case of the mentioned dimensions, the desired flexibility is obtained as a result of the plastic material used. However, such a catheter intermediate tube has only a limited resistance to transverse forces, i.e. the stability of the effect of the compression of the catheter intermediate tube together with the possible reduction of the flow rate of the liquid in the effective inner cross section is relatively low. In certain applications, bending of the catheter intermediate tube may also occur, whereby the flow through the bending site may be completely blocked or at least almost completely interrupted.

The invention is based on the object of providing an indwelling cannula which is less sensitive to lateral forces and/or bending.

According to an advantageous embodiment of the invention, the intermediate conduit pipe has at least one support structure by means of which the bending and/or radial resistance of the intermediate conduit pipe is increased. The support structure may be constructed in the form of one or more reinforcing elements.

According to an advantageous embodiment of the invention, the central tube of the catheter has a plurality of lateral through openings extending from the inner side to the outer side. The through openings (Side Holes) may be present over the entire length of the catheter intermediate tube or may be present only on one or more longitudinal sections, for example in sections closer to the hollow body. The through openings may be arranged distributed over the circumference of the catheter intermediate tube. The flow of liquid through the intermediate tube of the catheter can be improved by the through openings in the intermediate tube wall of the catheter.

According to an advantageous embodiment of the invention, it is provided that the housing has a protective projection for protecting the catheter intermediate tube, which protective projection extends distally from the intermediate tube exit region of the housing, wherein between the protective projections, at least on the patient application side of the indwelling catheter, there is at least one slit extending in the longitudinal direction, which is at least as wide as the diameter of the catheter intermediate tube, so that the catheter intermediate tube can extend in a uniform arc through the slit when the indwelling catheter is placed against the patient. In this way, in the region of the exit point from the housing, a bend protection and at the same time a fracture protection for the catheter intermediate tube is achieved. The catheter intermediate tube is also laterally protected by a protection protrusion extending at least a section in the longitudinal direction. On the side of the housing facing away from the patient administration side, a slit may additionally be present, through which the catheter intermediate tube likewise can extend. The side of the indwelling cannula on which the indwelling cannula can be fastened to the patient due to its structure is considered the patient administration side of the indwelling cannula, e.g. the underside of the fixing wings.

The length of the protective projection and/or slit may be at least ten times the diameter of the catheter intermediate tube. In this way, a relatively large guide length for the catheter intermediate tube is achieved between the protective projections in the longitudinal direction. Furthermore, in a sensitive transition region from the housing of the indwelling cannula into the patient, protection of the catheter intermediate tube against environmental influences is provided.

According to one advantageous embodiment of the invention, the retention sleeve has a holding region which is set up for the user to hold the retention sleeve in the holding region during operation. The holding region of the retention sleeve can here be the following region: there are no other functions or functional elements of the indwelling cannula in said area, but said area is provided only for manual gripping of the indwelling cannula. This has the following advantages: the user intuitively grasps the indwelling cannula at the correct site, thereby avoiding unnecessary touches at other sites, e.g. where the indwelling cannula should absolutely remain sterile. In this way, unnecessary contamination of a specific portion of the indwelling cannula can be avoided. For example, the holding region may be formed at the housing of the catheter, for example, formed in one piece with the housing. The gripping area may be realized, for example, by correspondingly designing an area of the outer surface of the housing.

The indwelling cannula may also be fitted with a separate member, i.e. a grip, which may be removed after the indwelling cannula has been placed against the patient. If such a grip is present, the grip region is at the grip. Such a grip may be configured such that it at least partially or largely encloses the structure of the indwelling cannula that is outside the patient after the indwelling cannula has been abutted. However, the grip may also completely enclose the structure. In an advantageous embodiment, the grip element also surrounds the catheter intermediate tube over a partial length in a region remote from the hollow body, in particular in the region of the catheter intermediate tube protruding from the housing, i.e. in the region of the intermediate tube exit of the housing. Thus, the area is protected from contamination by pathogens.

The grip may be removed by pulling it down from the indwelling cannula up (away from the patient). However, in an advantageous embodiment, the grip element can also be pulled back towards the user for removal. The grip element can be formed in one piece or in multiple pieces. In a multi-piece construction, individual portions of the grip may be selectively removed, retained, or re-engaged to the indwelling cannula. Thus, special cases can be considered in which only a defined partial region of the indwelling cannula has to be protected in particular.

According to one advantageous embodiment of the invention, the indwelling catheter has at least one adhesive fastening element for self-adhesive fastening of the indwelling catheter to the patient. In the delivered state of the indwelling cannula, the adhesive fastening element may be covered at the adhesive side by a protective film. If the indwelling cannula is to be fixed at the patient, the protective film can be removed in a simple manner and the indwelling cannula is then fastened directly to the patient by means of the adhesive fastening element. The protective film can be improved by means of a structure which protrudes, in particular laterally, beyond the protective film. For example, the structure may be configured as a connection plate that itself does not have adhesive properties. The protective film can then be removed from the indwelling cannula at the connection plate, without having to lift the indwelling cannula up for the removal process. This may improve patient comfort and also serve to not cause trauma to the anatomy due to unnecessary movement of the indwelling cannula. The use of the protective film has the following advantages: the user does not have to provide a separate adhesive fastening mechanism in order to fasten the indwelling cannula to the patient, such as a band-aid or the like.

For example, the adhesive fastening element may be arranged as an adhesive coating on the patient-applied side of the fastening flap of the indwelling cannula, or may be arranged as a separate adhesive tape on the side of the fastening flap facing away from the patient-applied side.

Alternatively or additionally to the adhesive fastening element, at least one needle-shaped or spiral-shaped structure may be present, by means of which the indwelling cannula may be fastened to the skin. The needle-shaped or spiral-shaped structure may be surrounded by a protective cover, which can be actively removed by the user in order to avoid injuring the patient and the user.

According to an advantageous embodiment of the invention, a securing wing for securing the indwelling cannula to the patient is provided at the housing. The fixed wing is connected with the housing via a material bridge. The material bridge does not extend in the longitudinal direction over the entire extension of the fastening wings, but rather has a recess or interruption through which the adhesive tape can be guided, by means of which the indwelling cannula can be fastened to the patient. For example, the recess can be provided at a section of the retaining wing pointing towards the proximal end of the retention sleeve, i.e. the material bridge is then on the side of the retaining wing pointing towards the distal end.

According to an advantageous embodiment of the invention, the indwelling cannula has at least one retaining wing or an arrangement of retaining wings, which are coupled to the housing via a movement mechanism by means of which the position of the entire retaining wing or the entire arrangement of retaining wings relative to the housing can be adjusted. This has the following advantages: the retaining flap or the arrangement of retaining flaps can initially be arranged in a position which is particularly suitable for abutment when the indwelling cannula is in abutment with a patient and can be adjusted after abutment with the patient into a position which is particularly suitable for fastening purposes. For example, the fixing wing or the arrangement of fixing wings can be fastened to the housing in a longitudinally movable manner, so that the fixing wing or the arrangement of fixing wings can be pushed forward relative to the housing, i.e. towards the patient, after being brought into abutment with the patient. For example, the fixing wings or the arrangement of fixing wings may also be connected to the housing via a tilting mechanism via which the fixing wings or the arrangement of fixing wings can be pivoted into a position suitable for fastening on the patient. In particular, the retaining wings or the arrangement of retaining wings may pivot about a pivot axis extending transversely to the longitudinal direction of the indwelling cannula.

The invention is described in more detail below with reference to the accompanying drawings according to embodiments. The drawings show:

figure 21 shows an indwelling cannula according to an exploded view,

figure 22 shows the indwelling cannula in a perspective view,

figure 23 shows in a cross-sectional view the indwelling cannula according to figure 22,

figure 24 shows in a side cross-sectional view the indwelling cannula according to figure 22,

figures 25 to 27 show side cross-sectional views of a section of the catheter intermediate tube,

fig. 28 to 50 show other embodiments of the indwelling cannula.

The indwelling cannula 201 shown in fig. 21 according to the way of an exploded view has a catheter 202 and a needle device 203. The catheter 202 has a housing 2020 at which there is an intermediate tube exit region 2021 at the patient-facing side, at which the catheter intermediate tube 2022 exits from the housing 2020 and protrudes therefrom. The catheter intermediate tube 2022 is relatively flexible in construction and serves as an administration possibility for introducing liquids, in particular drugs, by intravenous infusion. The catheter intermediate tube 2022 is then positioned with its distal portion in a hollow body, such as a vein of a patient. The needle device 203 has a piercing needle 2030 which, in the basic state of the indwelling cannula 201, is largely in the housing 2020 and the catheter intermediate tube 2022, with the tip 2031 of the piercing needle 2030 protruding from the distal end of the catheter intermediate tube 2022. The needle device 203 can be moved in the longitudinal direction L relative to the catheter 202.

At the housing 2020, fixation wings 2023 are provided for manual operation and securing the catheter 202 at the patient. On the side facing away from the intermediate tube exit region 2021, the housing 2020 has a needle opening 2025 through which the piercing needle 2030 can be placed in the housing 2020 and the catheter intermediate tube 2022. The needle device 203 is removed after the indwelling cannula is placed against the patient. Needle opening 2025 is then used as a connection possibility for, for example, an infusion line or an extraction element, such as a syringe.

There may also be an injection port at the housing 2020, which protrudes from the housing 2020, for example on a side facing away from the fixing wings 2023. The injection port is used for injecting a drug. Otherwise the injection port is closed by means of a luer lock closure cap.

Needle device 203 also has a closure plug 2033 and an operating element 2032 at the proximal end of the piercing needle 2030. In the basic state, the needle opening 2025 is closed by the closing plug 2033. The operating element 2032 is used for operating the needle device 203 by a user, i.e. basically for pulling back the puncture needle 2030 after the puncture is completed. As mentioned, the needle device 203 is removed after the catheter 202 is placed against the patient.

Fig. 22 to 24 show an advantageous embodiment of the catheter 202 in different views. In the illustrated conduit 202, the conduit intermediate tube 2022 is supported in a radial direction by a support structure 2027. The support structure 2027 may be configured, for example, as a spiral-shaped wire that is disposed inside or outside the wall 2012 of the catheter intermediate tube 2022 or is integrated into the wall 2012. The spiral wire is wound in the longitudinal section a more closely than in the longitudinal section b, i.e. there is a greater spacing between the individual coils of the spiral than in the longitudinal section a. For example, the longitudinal section a may extend from a region within the housing 2020 toward the distal end to, for example, 60% to 90% of the length of the catheter intermediate tube 2022. The longitudinal section b starts at the end of the longitudinal section a and ends near the distal end of the catheter intermediate tube 2022. In the longitudinal section b, a through opening 2026, i.e. a lateral through opening (side opening), may additionally be provided in the wall of the catheter intermediate tube 2022, through which the liquid may also flow out laterally before reaching the distal end of the catheter intermediate tube 2022.

If no coating is present in the region, the desired liquid penetrability of the catheter intermediate tube 2022 is achieved by the greater spacing of the windings of the helical wire. In this case, liquid penetrability can be achieved even without lateral through openings.

Fig. 25 shows an advantageous embodiment of the configuration of the catheter intermediate tube 2022 in the region of the transition from the longitudinal section a into the longitudinal section b. In the illustrated embodiment, the wall 2012 of the catheter intermediate tube 2022 is constructed in multiple layers. There is an inner layer 2014 which simultaneously forms the inner side 2011 of the wall 2012. There is also an outer layer 2013 that is disposed outside of the inner layer 2014 and forms an outer side 2010 of the wall 2012. An intermediate space 2015 may exist between the inner 2014 and outer 2013 layers, in which a support structure 2027 is disposed. The areas of intermediate space 2015 not filled by support structure 2027 may be filled with additional material. The helical support structure 2027 may be a round wire or flat wire helix or a combination thereof. In the longitudinal section a, the distance P between the individual coils of the spiral can be, for example, in the range of 0 mm to 2 mm. The spiral may also have a varying pitch or a plurality of spirals with different pitches.

Fig. 26 shows an embodiment of a conduit intermediate tube 2022 having a support structure 2027 integrated directly into a wall 2012 of the conduit intermediate tube 2022. This can be produced, for example, by a coextrusion process, in which the catheter intermediate tube is coextruded with a wire forming a spiral.

As shown in fig. 26, the individual coils 2028 of the spiral need not necessarily be arranged exactly centrally in the wall 2012, but can also be arranged more toward the outside 2010 or toward the inside 2011. The coil 2028 may also protrude slightly from the outside 2010 or the inside 2011 so that a correspondingly uneven (wave-shaped) surface is derived. In an advantageous embodiment, the outer diameter D2 of the coil 2028 is smaller than the outer diameter of the catheter intermediate tube 2022, and/or the inner diameter D1 of the coil 2028 is larger than the inner diameter of the catheter intermediate tube 2022.

Fig. 27 shows a section of the catheter intermediate tube 2022 in the transition region from the longitudinal section a into the longitudinal section b. It can be seen how the helical support structure 2027 transitions from a smaller pitch of the coils 2028 into a larger pitch of the coils in the longitudinal section b. In the longitudinal section b there is also a through opening 2026, wherein it can be seen that the through opening 2026 is arranged between the coils 2028.

Fig. 28 shows an indwelling cannula 201 in which a kink protection 2016 is formed in the intermediate tube exit zone 2021 at housing 2020. Fig. 28 shows the indwelling cannula 201 in a perspective view, fig. 29 shows the indwelling cannula in a side sectional view, and fig. 30 shows an enlarged view of the area a marked in fig. 29. For example, the bend protection structure 2016 may be formed in a recess 2018 radially surrounding the conduit intermediate tube 2022 with a wall with a convex curvature that arches toward the conduit intermediate tube 2022, similar to the sound emitting side of a horn. The bend protection structure 2016 may have a rotationally symmetric shape. The recess 2018 may extend concentrically around the conduit intermediate tube 2022. If the tube intermediate tube 2022 is now bent to one side in the region of the intermediate tube exit region 2021, the flexible tube intermediate tube 2022 abuts against the curved wall of the bend protection structure 2016, thereby preventing bending, at least under moderate loading.

Fig. 28 and 29 also show that the needle device 203 can have a connection port 2034 at the proximal end, i.e. in the region of the operating element 2032, for connecting a syringe or infusion line, for example for drawing blood. The connection port 2034 is closed by a closing cover 204. For example, the closure cap 204 may be screwed or plugged in.

Fig. 31-33 illustrate one embodiment of an indwelling cannula 201 in which the bend protection structure 2016 is shaped substantially similarly to that in the embodiment of fig. 28-30, with the differences set forth below. Fig. 31 shows the indwelling cannula in a perspective view, fig. 32 shows the indwelling cannula in a side sectional view, and fig. 33 shows an enlarged view of a region B marked in fig. 32.

It can first be seen that the recess 2018 is formed with a wall that is arched toward the catheter intermediate tube 2022 with a convex curvature, wherein the curvature is smaller than in fig. 28 to 30. The recess 2018 is formed at a more acute opening angle than in the embodiment of fig. 28-30. Additionally, a plurality of, for example three, slit-shaped recesses 2017 extending in the longitudinal direction L are formed into the housing 2020. The slit-shaped recess 2017 begins at the intermediate tube exit region 2021 of the housing 2020 and extends into the housing 2020 at a particular measure, for example along the length of the recess 2018. The slit-shaped recess 2017 makes it possible to move the catheter intermediate tube 2022 in a specific direction, which is defined by the slit-shaped recess 2017, over an extended range with respect to the housing 2020.

A hinge may also be provided in the transition region of the housing 2020 with respect to the respective fastening wing 2023, so that the respective fastening wing 2023 can pivot about the hinge, i.e. can be connected to the housing 2020 in a reversible manner. This applies to all embodiments of the invention.

Fig. 34-36 illustrate one embodiment of an indwelling cannula 201 in which the kink protection feature 2016 itself has increased flexibility or resiliency relative to the housing 2020. Fig. 34 shows the indwelling cannula 201 in a perspective view, fig. 35 shows the indwelling cannula in a side sectional view, and fig. 36 shows an enlarged view of the region C marked in fig. 35.

For example, the bend protection structure 2016 may be constructed similar to a bend protection for an electrical line exiting from a housing of an electrical device. For example, the flexible bend protection structure 2016 may be formed from a plurality of loops 2019 disposed sequentially around the catheter intermediate tube 2022 in the longitudinal direction, the loops being connected to one another and to the housing 2020 by tabs 2040. For example, the housing 2020 may be connected with the first ring 2019 via two connection tabs 2040 disposed at opposite sides. The first ring 2019 may be connected with the second ring 2019 via two connection tabs 2040 disposed at opposite sides, wherein the connection tabs 2040 between the first ring and the second ring 2019 may be disposed at a particular angular offset, e.g., 90 degrees, in the circumferential direction relative to the connection tabs 2040 between the housing 2020 and the first ring 2019. In the same way, the other rings 2019 can be connected to the respectively adjacent rings 2019 via two connecting pieces 2040, wherein the connecting pieces can again be alternately offset in the circumferential direction by a specific angle, for example 90 degrees. The bend protection structure 2016 formed in this manner may be relatively flexible in construction, such as from an elastomeric material, such as rubber.

As also shown in fig. 35 and 36, a recess 2018 of the type described above, for example in the shape of a horn, can also be formed in the bend protection structure 2016 formed by the ring 2019 by means of the connecting piece 2040.

Fig. 37-39 illustrate one embodiment of an indwelling cannula 201 in which the kink protection structure 2016 is formed by a plurality of pins 2041 that protrude from the housing 2020 in a longitudinal direction toward the distal end of the indwelling cannula 201. Fig. 37 shows an indwelling cannula 201 in a perspective view, fig. 38 shows the indwelling cannula in a side sectional view, and fig. 39 shows an enlarged view of a region D marked in fig. 38.

The pins 2041 are each arranged at a distance from one another which is so great that the catheter intermediate tube 2022 can extend into such an intermediate space when under bending load. Furthermore, the pin 2041 may be spaced apart from the catheter intermediate tube 2022 in the radial direction, i.e. a certain free space is formed around the catheter intermediate tube 2022, so that a more free movability of the catheter intermediate tube 2022 may be achieved under bending loads.

In general, the bend protection structure 2016 in all of the described embodiments has the following advantages: an increased bending radius of the catheter intermediate tube 2022 in the intermediate tube exit region 2021 is ensured, and thus possible bending of the catheter intermediate tube 2022 in said region is counteracted.

If the bending protection structure does not have, for example, slit-shaped recesses 2017 or pins 2041, but is comparatively solid, it can also have an increased elasticity relative to the elasticity of the housing 2020. Bending of the catheter intermediate tube 2022 in the intermediate tube exit region 2021 may also be resisted thereby. Fig. 40-42 illustrate one embodiment of an indwelling cannula 201 in which such a bend protection structure 2016 is used. Fig. 40 shows an indwelling cannula 201 in a perspective view, fig. 41 shows said indwelling cannula in a side sectional view, and fig. 42 shows an enlarged view of the area E marked in fig. 41.

The bend protection structure 2016 may be constructed as a separate member from the housing 2020, and is advantageously constructed of a material having a higher elasticity than the material of the housing 2020, such as an elastomeric material or a silicone material. Fig. 40 to 42 show an embodiment of a fold protection structure 2016 that is formed in solid form. It is also possible that such a bend protection structure 2016 constructed of a more resilient material has one or more of the previously mentioned features of the bend protection structure 2016, such as the recess 2018.

Fig. 43 to 46 show an embodiment of the indwelling cannula 201 in which, in order to form a gripping area on the left and right of the housing 2020, respectively, there is a gripping surface 2044 for manual gripping and manipulation of the indwelling cannula 201. Fig. 43 shows a perspective view of the indwelling cannula 201, fig. 44 shows a proximal end portion of the indwelling cannula 201 in a top view, fig. 45 shows the indwelling cannula 201 in a state of being administered to a patient, and fig. 46 shows a partial cross-sectional view of the indwelling cannula 201 in a state of being administered to a patient.

For example, the gripping surface 2044 may be grooved in the lateral direction. In addition, the housing 2020 has two protection protrusions 2042 that continue in the distal direction from the catheter intermediate tube 2022 on the left and right. As shown in fig. 46, a protective projection 2042 extends from the housing 2020 at the intermediate tube exit region 2021. Guide slits 2043 are provided above and below the catheter intermediate tube 2022 between the protection protrusions 2042, respectively. In particular, the lower guide slit 2043 may realize that the catheter intermediate tube 2022 extends with a gentle curve towards the patient 205 in a state of being abutted against the patient 205, i.e. the guide slit 2043 provides space for a defined curve of the catheter intermediate tube 2022 and prevents the catheter intermediate tube 2022 from buckling or breaking. The catheter intermediate tube 2022 is additionally laterally protected in this region by a protection projection 2042. A protective cover receptacle 2046 may be formed at the protective projection 2042, for example in the form of a recess extending into the protective projection 2042. In this manner, the protective cap can be plugged onto the needle tip 2031 and the catheter intermediate tube 2022 and fastened to the housing 2020.

The gripping surface 2044 may extend toward the distal end into the region of the protective projection 2042. Advantageously, a finger stop device 2045 is provided at the distal end of the housing 2020 or the protective projection 2042, for example in the form of a thickened portion, for example a ridge or a rim. Thereby preventing the user from slipping off of the housing 2020 or the gripping surface 2044 with their fingers forward toward the patient 305, for example, when the indwelling cannula is placed against the patient 205.

It can also be seen that in the embodiment of fig. 43 to 46, the tie wings 2023 are connected to the housing 2020 only by means of relatively narrow material bridges 2029. Correspondingly, the securing wings 2023 extend freely from the housing 2020 over a longitudinal region, so that there is formed an intermediate space with the housing 2020, through which the adhesive tape can be guided, for example, in order to secure the securing wings 2023 at the patient 205.

Fig. 47 and 48 show an embodiment of the catheter in which the fixing wings 2023 are movably, i.e. linearly movably arranged in the longitudinal direction L with respect to the housing 2020. Fig. 47 shows the indwelling cannula in a basic state, i.e. a delivery state. Fig. 48 shows the indwelling cannula 201 without the needle device 203 after being placed against the patient 205. Fig. 47 and 48 show perspective views, respectively.

The fixed wing 2023 is at one side at a rear wing carrier 2051, which in the basic state shown in fig. 47 is close to the proximal end of the indwelling cannula 201, and at a front wing carrier 2051, which is spaced apart from the rear wing carrier 2051 in the longitudinal direction L, and is correspondingly disposed close to the distal end of the indwelling cannula 201. The rear wing carrier 2051 is connected to the sliding sleeve 2048 via a hinged connection 2050. The sliding sleeve 2048 is connected to the front wing carrier 2051 via a longitudinal connector 2049. In this way, all the fixing wings 2023 are connected to each other as one unit.

The housing 2020 has a sliding section 2047 for longitudinally moving the sliding sleeve 2048 over the sliding section 2047. Thus, the sliding section 2047 has a cross-sectional profile and cross-sectional dimensions that remain unchanged over its longitudinal extension. Fig. 47 and 48 show the sliding section in a cylindrical shape, but the sliding section may also have other shapes, for example a polygonal shape.

The indwelling cannula 201 in the basic state shown in fig. 47 is in conventional manner held against the patient 205. Then, if the indwelling cannula 201 should be fixed to the patient 205, the unit at which all fixing wings 2023 are movable by means of sliding sleeve 2048 continues to be pushed along the sliding section 2047 from the proximal end until the position shown in fig. 48 is reached. In this position, the indwelling cannula 201 may be fixed to the patient 205 by taping the fixation wings at the anterior and posterior wing carriers 2051, respectively.

In the basic state, the front wing carrier 2051 is disposed above the housing 2022 and the rear wing carrier 2051 is disposed below the housing 2022, respectively, as viewed from the patient administration side. In the state of administration to the patient 205, the two wing carriers 2051 are directly at the patient 205, i.e. at the same height level. The catheter 202 is thereby placed in a suitable inclined position, by means of which the catheter intermediate tube 2022 is prevented from being bent unnecessarily in the intermediate tube exit region 2021. It can furthermore be seen that in this position, the longitudinal connector 2049 forms an advantageous protective cover for the section of the catheter intermediate tube 2022 that is outside the patient 205.

Fig. 49 and 50 show in a view similar to fig. 47 and 48 an indwelling cannula 201 with an alternatively designed movable device for adjusting the position of the securing wings 2023. In the embodiment, there is a wing carrier 2051 formed in the form of two bodies extending laterally along the housing 2020, at which two fixing wings 2023 are provided at the front and rear end, respectively. The wing carrier 2051 is pivotally secured at the housing 2020 via a pivot axis 2052. Fig. 49 shows the indwelling cannula 201 in a basic state. In this state, the free pivotability of the wing carrier 2051 can be prevented by the retaining element, whereby the wing carrier 2051 does not undesirably change its position during the administration of the indwelling cannula 201 to a patient. For example, the operating element 2032 can serve as a holding element, which can be connected to the housing 2020 via a flexible tab and can be deflected manually in this way in order to release the fixing of the wing carrier 2051.

If the wing carrier 2051 is pivoted into the position shown in fig. 2050 when the indwelling cannula 201 is placed against the patient 205 and should be fastened thereto, the fixation wings 2023 are placed against the patient 205 and may be fastened thereto by means of adhesive tape. In said pivot position, the wing carrier 2051 can be fixed by means of a locking device via at least one fixing pin 2053 engaged into the recess. Thereby locking the housing 2020 in a particular pivot position relative to the wing carrier 2051.

In all embodiments of the invention, the operating element 2032 may have a structuring, for example in the form of grooves, on the side facing the patient and/or on the side facing away from the patient. The fixation wings 2023 may be configured such that they are kneadable or moldable such that they can be matched by a user in a simple manner to the corresponding surfaces of the body region of the patient where the indwelling cannula 201 is provided.

3. Description of the embodiments

Puncture device

The invention relates to a puncturing device for puncturing a hollow body by means of a puncturing needle, wherein the puncturing device has at least one tubular outer sheath in which a puncturing needle can be guided in a longitudinally movable manner, wherein the outer sheath is designed to push over at least a portion of the length of the outer sheath and to remain there for a certain duration after puncturing the sheath of the hollow body to be punctured has been performed by means of the puncturing needle through an opening of the sheath of the hollow body to be punctured.

Such a puncturing device is also referred to hereinafter as a puncturing system, in particular as an intravenous cannula when it relates to the medical field. The tubular outer sheath or simply "outer sheath" is also referred to hereinafter as the venous catheter. The hollow body to be pierced may be a biological hollow body or may also be a hollow body of an object. The hollow body may be, for example, a blood vessel, such as a vein or an artery, as long as the lancing device relates to the medical field.

The terms "puncture" and "perforation" are to be understood herein in a medical sense. Puncturing means that a puncture needle is pierced into the hollow body such that the puncture needle penetrates the envelope of the hollow body to be punctured.

The portion at the distal (distal) end of the lancing apparatus, and thus near the hollow body being lanced, is seen from the user's perspective as a section of the portion of the lancing apparatus near the hollow body. Correspondingly, the section remote from the hollow body is arranged at the end of the lancing apparatus that is proximal from the user's perspective, i.e. further from the hollow body being lanced. In connection with medical application of the lancing apparatus, the term proximal to a vein or proximal to a patient is also used synonymously with the term proximal to a hollow body, and for the term distal to a hollow body, distal to a vein and distal to a patient are also used.

An improved puncture system in the sense of a generic puncture system should be produced. In principle, it is also possible with the aid of the improved venous indwelling cannula to advantageously puncture all body cavities and body spaces to be punctured and all anatomical and pathological structures and to place catheters therein.

In principle, the components of the improved venous indwelling cannula may also be used in combination with all known puncture and catheter systems, or also as a stand alone product.

Although the term "venous indwelling cannula" shall be retained hereinafter, it has a broad meaning in the sense of a general puncture system by means of which not only veins can be punctured. That is, in the following, the terms "vein" and "veins" in principle include all blood vessels and more generally all body cavities and body spaces as well as all anatomical and pathological structures that should be penetrated and that should be provided with a catheter.

Thus, with the aid of the venous indwelling cannula, the trachea, pleural cavity, abdominal cavity, stomach, intestine, renal pelvis, bladder, subarachnoid space and bone can additionally be penetrated by way of example. Additionally, pathological structures, such as abscesses, may be punctured in and on the patient. Advantageously, arterial blood vessels can also be punctured.

Hereinafter, "proximal to a vein" may generally be equivalent to "proximal to a patient" and "distal to a vein" may generally be equivalent to "proximal to a user". The parts near the vein tend to be inside the patient and the parts far from the vein tend to be outside the patient. This does not necessarily apply forever, but the term should be further clarified. The supplemental content is self-evident as specified, and the context is decisive.

All the components described can be used one or more times at the venous indwelling cannula or also independently of such indwelling cannula at/in other products or completely independently. The different features of the different components may also be combined freely and the features of a particular component may also be used at other components without explicit mention. In principle, all components and features can be applied both inside and outside the patient.

Special cross section of venous catheter

According to an advantageous embodiment of the invention, it is provided that the outer sheath and/or the further part of the puncturing device has one or more flow channels which extend largely or completely in the longitudinal direction of the puncturing device and through which fluid flowing through the punctured hollow body can flow alongside the outer sheath and/or the further part of the puncturing device. Such a flow channel may be formed, for example, by a groove-shaped or groove-shaped recess at the outer side of the outer envelope, for example a groove or a channel in the wall of the outer envelope. The flow channel can also be designed partly as a recess and partly as a channel in the wall of the outer envelope, which varies over its length. The flow channels do not have to be present over the entire length of the outer envelope. For example, the flow channel may be provided only or for the most part in a section of the outer envelope which is provided for being left in the hollow body. This applies to one, more or all flow channels. In particular, the flow channel of the outer envelope may extend largely or completely in the longitudinal direction of the outer envelope.

The venous catheter may be circular or elliptical in cross-section. One side of the circle or ellipse may have at least one flattened portion, recess or eversion. The venous catheter can thus also be optimally adapted to veins which do not have a purely circular cross section. The venous catheter may be wholly or partly composed of a thermoplastic material, e.g. a plastic material, over part of its length, most of its length or the entire length, said thermoplastic material having the property that it no longer retains the specific shape of the venous catheter at body temperature, so that the venous catheter can optimally be adapted to the shape of the vein. Thus, the wall of the venous catheter may rest against the wall of the vein. Thus, if the fluid flow is administered via an intravenous catheter, the intravenous catheter may hold the lumen of the vein open for fluid flow through the intravenous catheter. If such fluid flow is no longer administered via the intravenous catheter, the intravenous catheter collapses due to the apparent thermoplastic properties, thereby closing itself. This has the following advantages: fluid, such as blood, can no longer flow undesirably from the patient via the intravenous catheter.

The venous catheter may likewise have at its outer side at least one groove-shaped/channel-shaped recess. The recess may be, for example, a longitudinally extending recess. Thereby, fluid flow can be achieved alongside the intravenous catheter even when the intravenous catheter is in a vein. Thus, for example, outflow disturbances in the vein can be prevented in the case of an inserted venous catheter. In the area of arterial vessel puncture, this may be particularly important to prevent blood supply interference. The same is true if the actual lumen of the intravenous catheter is blocked or occluded, for example by coagulated blood. In the region of the recess, the venous line can be composed entirely or partially of or be coated with at least one material having antibacterial and/or anti-coagulable properties. Thus preventing the build-up of germs and/or blood clots in the area. At least one material having particularly advantageous flow guiding properties and less damaging to the particle components of the blood when it comes into contact with it can also be used in the region.

The recess need not be present over the entire length of the intravenous catheter. The recess can thus advantageously be formed without leaving the vein in the region of the transition of the venous catheter into the other components of the venous retention sleeve and/or also where the venous catheter is guided through the skin and subcutaneous tissue of the patient. Thus, there is no access port for pathogens in the area, as the skin and subcutaneous tissue may be placed completely around the catheter. The recess can likewise already end in front of the venous line near the tip of the vein, whereby it can be formed without edges (fig. 52, 53). The recess may also be created by: the venous catheter is at least partially, for example at its outer side, composed of at least one resorbable material which has a complementary shape to the recess and initially at least partially fills the recess. The recess is constituted if the material is now resorbed in the patient, for example when blood is in contact or when it is in contact with other fluids. The resorbable material may be a carbohydrate, but may also be other biomolecules or salts. The material may also be or comprise magnesium. Resorbable polymers, composite materials, bioceramic materials or biodegradable metals may likewise be used. The material may also be a combination of a plurality of resorbable materials.

Instead of the recess, it is also conceivable that at least one longitudinally extending channel is present in the wall of the venous catheter, which channel is delimited by the actual lumen of the venous catheter. The channel may start distally through a recess in the wall of the intravenous catheter and terminate proximally through a recess in the wall of the intravenous catheter directly in the region of the tip of the intravenous catheter or slightly distally from the tip (fig. 54-56). At least one additional fluid flow can thereby be achieved in the venous line.

Combinations of the groove-shaped/channel-shaped recesses and channels described above are possible.

An inflatable body for securing the position of the venous catheter in the punctured body part may be provided at the venous catheter of the venous indwelling catheter. Such an inflatable body can be configured, for example, as an inflatable collar, a so-called indwelling band (Cuff), which is arranged, for example, on the outside of the venous catheter. In an advantageous development, the expansion is embodied in that it can likewise have at least one groove-shaped/groove-shaped recess as described above, which is also held in the expanded state, so that a fluid flow around the expansion body can be achieved. It is also conceivable that the expansion body also comprises at least one channel as described above in the expanded state, whereby a fluid flow through the expansion body becomes possible. The channel may be kept open by a circumferential structure at least partly surrounding it and constituting a wall.

The venous catheter as described hereinabove may also be used independently of venous indwelling cannulas, for example in longer constructions with larger diameters as a hose for devices for performing extracorporeal membrane oxygenation (ECMO).

The cross section of the intravenous catheter may also be constructed similar to an externally toothed gear having at least one tooth. The gears may have 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 or more than 30 teeth. Alternatively or additionally, however, the cross section of the venous catheter may also have an internally toothed gear with the number of teeth just mentioned. It is also conceivable that at least one further lumen in the venous catheter has external teeth and that the venous catheter itself has internal teeth.

The configuration of the venous catheter cross section as a semicircle, semi-ellipse, arc or ring is equally possible, at least one flattened, concave or everted portion at each side of the geometry/shape (hereinafter just "shape"). Groove/channel shapes may also be present.

The inner and/or outer cross-section can also be rectangular, square, cross-shaped, parallelogram, diamond-shaped, triangular, pentagonal, hexagonal, octagonal or more generally polygonal. Frame-like, clover-like or crescent-like shapes are also conceivable.

The venous catheter may have a cylindrical, conical, cuboid or also prismatic shape. Pyramidal embodiments are also possible. The venous catheter may likewise have a winged-shaped profile, more precisely also a carrier winged-shaped profile.

It is possible that not only the inner side but also the outer side of the venous catheter respectively has at least one of the above-mentioned shapes, or is improved by means of a structure having at least one of the above-mentioned shapes. The outside and inside of the venous catheter may also differ in said characteristics. Thus, for example, it is conceivable that the outside of the venous catheter flexibly matches the shape of the vein, while the inside of the venous catheter has a comparatively rigid characteristic which keeps the lumen of the venous catheter open, for example against the action of external pressure. The rigidity may be achieved by a special shape of the inner side of the intravenous catheter, for example by an oval shape, but may also be achieved by using special materials, in particular metals, metal alloys and hard plastic materials. The rigid characteristic may also be achieved by a helical, wave-shaped or mesh-shaped surface on the inside of the venous catheter. Combinations with transversely extending, longitudinally extending or diagonally extending structures are conceivable, which themselves can also ensure the desired rigidity alone.

All mentioned and other geometries can be freely combined. Different sections of the venous catheter may also have different cross-sections or shapes.

The cross-section or shape may be altered by specific properties, such as thermoplastic properties, when the intravenous catheter is subjected to different environmental conditions, such as body temperature. The cross-section or shape may also change when the intravenous catheter is subjected to a certain pressure, either internally or externally. It is thus for example conceivable to create a universal vascular catheter which can be used not only under conditions of hypotension, for example in veins, but also under conditions of hypertension, for example in arteries and in the vicinity of the heart.

Combinations of different shapes may also be used to bound multiple tube lumens within an intravenous catheter with one another. Thus, for example, an intravenous line can have at least one lumen with a circular cross section and a further lumen with an elliptical or rectangular cross section. The cross-section can be optimized for the specific properties of the different fluids, respectively.

Inverted hook-shaped structure

According to an advantageous embodiment of the invention, it is provided that a barb-like structure is provided on the outside of the outer envelope, which makes the pulling-out of the puncturing device introduced into the hollow body difficult or prevents said pulling-out. Thereby preventing the lancing apparatus from inadvertently sliding out of the lanced hollow body.

Barbs or barb-like structures may also be provided at the outside of the intravenous catheter. For example, the structure may be constructed to be reversible or removable. The structure may also be activated by a fluid flow, a gas flow or a steam flow, for example. For example, the structure may also be activated by a blood flow, which may be pulsatile or non-pulsatile/continuous.

Thus, the structure may make it difficult or prevent the intravenous catheter from being pulled out or slid out of the vein. Venous catheters may also be constructed similarly to pins. It is conceivable that the structure at the outside, for example the elongated structure, moves away from the outside of the venous catheter, for example stands up protruding from the venous catheter, when the temperature rises to body temperature. The structure may also undergo a volume increase upon warming to body temperature. The structure can likewise be constructed in a fluid-absorbing manner and thus undergo a volume increase when in contact with a fluid, for example blood, steam or gas. Thereby, the intravenous catheter itself may stabilize its position in the vein.

The venous catheter can also be constructed as a telescopic tube, for example a telescopic tube, and can be adjusted in length. The telescopic tube can here consist of 2, 3, 4, 5, 6, 7, 8, 9, 10 or more than 10 elements which can be moved into each other, for example rings with different inner and outer diameters.

The matters described in this paragraph are equally applicable to lancets and catheters as well as hoses in general. The needle and catheter and hose may have the above characteristics and may be advantageously modified as just described.

Special construction of intravenous catheter with internal capillary system

According to an advantageous embodiment of the invention, it is provided that the outer envelope has an arrangement of a plurality of elongated cavities, which extend at least for the most part in the longitudinal direction of the outer envelope, wherein the cavities can be formed in particular in the form of capillaries.

Venous catheters may also be composed of a system of elongated cavities, for example capillaries, which may be of very thin-walled construction. The capillary tube may be formed as a glass capillary tube. For example, the capillary tube may have an outer diameter of between 0.01 mm and 2.5 mm, preferably between 0.05 mm and 0.5 mm. Smaller or larger outer diameters are also conceivable. The wall thickness/wall thickness (hereinafter simply "wall thickness") may for example lie between 0.002 mm and 0.25 mm, preferably between 0.01 mm and 0.05 mm. But smaller or larger wall thicknesses are also conceivable.

In the venous catheter thus constructed, capillary forces can advantageously act. The venous line thus constructed can advantageously also be wetted, for example, with other fluids or substances, for example anticoagulants or antibacterial substances.

The elongated cavity described hereinabove may also be constructed of another material, such as a plastic material or a metal or metal alloy. The material may be electrically conductive and may also function as a sensor, for example. Heating or cooling of the flowing fluid is contemplated, and both the concurrent and counter-current principles may be employed. The walls of the elongated cavity may be penetrable only for a specific substance over part, most or all of its length. Thus, the cavity may be semi-permeable, for example, or other diffusion processes may be implemented. It is also conceivable that the fluid flowing in the venous catheter removes harmful substances, for example to detoxify.

At least three-layer structure of venous indwelling cannula

According to an advantageous embodiment of the invention, it is provided that the puncturing device has a further tubular structure which is arranged between the outer sheath and the puncturing needle.

Thus, a construction of at least three layers of the venous indwelling cannula is possible. At least one further tubular/cylindrical structure, which may also be formed as a hose or a catheter, may also be present between the inner puncture needle and the outer venous catheter. The intermediate structure may also have another shape and for example have the cross-section mentioned above. The intermediate structure is arranged in a longitudinally movable manner with respect to the puncture needle at the inside and/or with respect to the intravenous catheter at the outside and/or in a rotatable manner about its longitudinal axis.

The wall of the intermediate structure may be formed by at least one layer and may partly, largely or completely enclose the puncture needle or the catheter further inside. The wall of the intermediate structure may preferably consist of at least two or three layers, wherein at least one layer has at least partially puncture-proof properties. For example, the layer having the characteristics may be at least partially composed of a metal, a metal alloy, or an aramid/aramid fiber. The intermediate structure may thus, for example, provide puncture protection for at least one externally located catheter relative to the tip of the puncture needle.

Likewise, the intermediate structure may also be configured in a semicircular or concave manner. In this embodiment, the intermediate structure only partially encloses the inner piercing needle. In a preferred embodiment, the intermediate structure surrounds the surface of the puncture needle in a semicircular or concave shape over a part or its entire length by at least 5% or 10%, in other preferred embodiments by at least 20%, 30%, 40%, 50%, 60%, 70%, 80% or 90%.

In addition to embodiments with smooth or convex surfaces, the intermediate structure may also be helically configured and provide a contoured surface. The intermediate structure may also be provided with a sealing coating, in particular a PTFE coating, and additionally reinforced by other structures or elements, for example by transversely extending, longitudinally extending or diagonally extending structures.

The intermediate structure may have a significantly reduced wall thickness compared to an externally located intravenous catheter. Thus, the wall thickness can be, for example, less than 90%, in advantageous embodiments even less than 80%, 70%, 60%, 50%, 40%, 30%, 20%, 10% or 5%.

The intermediate structure may also be configured as a conventional guide wire, for example a guide wire without a core, through which the puncture needle is guided in an internal manner longitudinally movable. In this case, the external venous line can also be omitted. A system of an internally located puncture needle and an externally located guide wire is thus created, which is used for placing the guide wire in a target structure, such as a vein.

Lotus effect

According to an advantageous embodiment of the invention, the outer side of the puncture needle and/or the inner side of the outer sheath has a surface layer, which is formed from a material having a higher sliding capacity than the remaining material of the puncture needle and/or the outer sheath. For example, a lotus effect can thereby be provided at the outside of the puncture needle and/or at the inside of the outer envelope.

The outer side of the puncture needle can be composed of or be coated with a material that is particularly slip-able. Alternatively or additionally, the inner side of the venous catheter may be composed of or coated with such a material. In particular, materials, coatings and/or surface structures which, alone or in combination with one another, cause the lotus effect can also be mentioned. Thus, hydrophobic characteristics up to superhydrophobicity can be achieved. The corresponding surface structure may in particular have projections, it being possible to use at least one wax layer advantageously. Thus, the self-cleaning properties of the corresponding surfaces of the needle and the intravenous catheter can be achieved. All other components and surfaces of the intravenous catheter may also be constructed in the manner just mentioned. It is envisaged that the flow resistance in the interior of the intravenous catheter is positively influenced.

Friction reducing properties between a needle and an intravenous catheter

According to an advantageous embodiment of the invention, it is provided that an additive substance, in particular an oil-containing or grease-containing substance, is provided on the outside of the puncture needle and/or on the inside of the outer envelope.

It is also possible that at least one oily or oleaginous-like substance is present between the needle and the intravenous catheter, said substance reducing the frictional resistance between the two. The substance may also have antibacterial or anti-hemagglutinating properties. In order to retain the substance in the space between the puncture needle and the intravenous catheter, the space can advantageously be modified by means of a terminating element close to the vein and remote from the vein, respectively. For example, the terminating element can be designed such that it partially or completely surrounds the puncture needle, for example in the form of a ring, and the puncture needle is guided longitudinally displaceably and/or rotatably about a longitudinal axis through a recess of the terminating element.

It is also conceivable that the at least one terminating element is supported in the venous catheter so as to be longitudinally movable. The terminating element can be connected to a control element, by means of which the position of the terminating element can be set by the user. If the lancet now has a structure or shape that increases the outer diameter of the lancet over at least a part of its length, the lancet can no longer pass through the terminating element over said part of its length. Thus, the length of the puncture needle tip extending out of the intravenous catheter near the vein can be variably set within specific limits.

The terminating element described hereinabove may constitute the surface of the wave form and/or may also be constituted in the form of a spring and/or a spiral. The terminating element described hereinabove may be composed of plastic, but may also be composed of metal or metal alloy. In order to form the terminating element gas, steam and/or fluid impermeable, it is also possible to coat or cover it with at least one additional material. The use of PTFE is contemplated herein.

Hollow guide wire as intravenous catheter

According to one advantageous embodiment of the invention, it is provided that at least the part of the outer envelope which is provided for being left in the hollow body has a helically wound, internally hollow guide wire over its entire length or over a large part of its length, in which length the puncture needle can be guided longitudinally displaceably. Thus, a cavity is present in the spiral structure, through which the puncture needle can be guided, for example.

It is also proposed that at least the part of the intravenous catheter which is set up for indwelling in the patient is constituted over its entire length or over a large part of its length by a guide wire from which the inner core has been removed, in which length the puncture needle can be guided longitudinally displaceably. The guide wire is thus hollow and is formed by a spiral structure. The spiral structure may also be formed as a flat wire. The spiral-shaped structure may be surrounded by a gas, vapor and/or fluid impermeable layer on the inside, outside or around it. The layer may be, for example, a PTFE layer or another material.

Puncture needle (tip) composed of resorbable material and having additional properties

According to an advantageous embodiment of the invention, it is provided that the portion of the puncture needle adjacent to the hollow body is formed blunt and/or from a bioresorbable material and/or that any region of the puncture needle is formed from or coated with a bioresorbable material and/or that at least a portion of the outer sheath is formed from or coated with a bioresorbable material. Such bioresorbable materials have the following advantages: it dissolves in the body of the living being after a certain time by the substances present there. If resorbable materials are mentioned hereinafter, this also includes bioresorbable materials.

It is therefore possible for the section of the puncture needle that is located close to the vein to be formed not sharp, but rather blunt. The sections can thus also be formed, for example, in the shape of struts. If the segments are formed blunt, other applications in solid tissue or also in softer tissue, such as the brain, can be developed where a sharp penetration is not necessary for passing through the tissue and may cause damage thereto.

In principle, the puncture needle can be hollow or hollow. If the puncture needle is not hollow, it is possible to avoid flushing out the tissue, which may drag it into deeper anatomical structures. The puncture needle can also be formed here with an inner core or other reinforced, but also flexible structure or material. The puncture needle may also comprise an internal probe (Mandrin), which is hollow or not hollow in itself. Preferably, the tip of the needle proximal to the vein may also be constructed of, or coated with, a resorbable/dissolvable (hereinafter simply "resorbable") material.

The resorbable material may be a carbohydrate, but may also be other biomolecules or salts. The material may also be or comprise magnesium. Resorbable polymers, composite materials, bioceramic materials or biodegradable metals may likewise be used. The material may also be a combination of a plurality of resorbable materials and may also contain or be coated with at least one of an antimicrobial or anticoagulant or other efficacious or bioactive substance.

Thus, the shape of the needle tip may change upon blood contact or other fluid contact, e.g., the needle tip near the vein may be partially or fully resorbed. Depending on the materials used, the process can be carried out very rapidly, for example within 1 second, 30 seconds or 1 minute or 2 minutes or 5 minutes. However, the process may also be performed more slowly, e.g. requiring at least 1 hour, at least 1 day, at least 1 week, at least 1 month, at least 3 months or 6 months or at least 1 year.

It is also conceivable that the tip of the puncture needle, which is located close to the vein, is only partly composed of or coated with at least one resorbable material. The tip can thereby be given a desired shape when in contact with blood or other fluids, and the type of edging can also be varied, for example. This can be achieved by: the resorbable material exposes the underlying and adjacent material having a different shape than the resorbable material. The material exposed in this way may likewise be resorbable, for example also be resorbable more slowly or else not resorbable.

It is specifically contemplated that the piercing needle tip is formed with a sharp edging of at least one resorbable material. If the material is now resorbed in the patient, for example upon blood contact or other fluid contact, the needle tip may thereby become blunt when structures are now exposed, for example structures that do not constitute sharp edging and straight cuts and that are constituted by at least one non-resorbable material. This results in a puncture needle whose tip adjacent to the vein can be self-dulled, for example, when blood comes into contact, so that, for example, the vein rear wall can no longer be pierced in an undesirable manner. It is also advantageous that the patient and user can no longer be endangered when removing the now blunt lancet from the body, and that additional safety devices, such as puncture protection, are no longer needed.

It is also conceivable to use materials which undergo a change, for example a change in shape, as a result of a gas, steam or fluid flow. The shape change can thus be brought about, for example, by means of such a flow, so that, for example, at least one molecular layer is removed by means of the flow, advantageously also directly by means of the flow.

In this context, it is conceivable that at the end of the venous catheter remote from the vein and/or at a further component of the venous indwelling cannula, for example an extension element which may be at least partially hollow, there is an element which generates a gas, steam or fluid flow intermittently or continuously, at least for a specific period of time. The flow may advantageously be directed directly to the vein. Elements that generate negative pressure to flow away from the vein, i.e. towards the user, are also conceivable. Thus, the shape and/or edging of the needle can be modified as it is advanced into the vein.

It is also conceivable that the structure exposed by the resorption of the further material is constructed identically or similarly to the push button sleeve. For example, the end of the cannula near the vein may be rounded or widened.

It is also contemplated that the opening at the needle tip and/or the lumen of the needle tube remain partially or completely open by the at least one resorbable material. If the material is now resorbed, for example by blood contact or other fluid contact, the opening of the needle tip or the lumen of the needle is closed. This may be important, for example, if the administration of a fluid or drug into a blood vessel is not desired, but access to the blood vessel by means of a puncture needle cannot be excluded.

For example, the effect just described may be achieved by: the at least one resorbable material forms a support rod which partially or completely holds open the opening at the tip of the puncture needle and/or the lumen of the tube of the puncture needle, but no longer holds open in the case of resorption.

It is also conceivable that the puncture needle is reinforced at the inner and/or outer side of its wall with a resorbable material which holds the wall in a position in which the opening at the puncture needle tip and/or the tube lumen of the puncture needle are partially or completely open.

In one advantageous embodiment, at least a part of the puncture needle is made of an elastic material.

It is also conceivable, however, that the opening of the puncture needle tip and/or the tube lumen of the puncture needle is narrowed in its diameter by at least one resorbable material, and that the opening and/or the tube lumen is subjected to an increase in its inner diameter by the resorption of the material. This may be particularly important if the shoot out effect should be avoided. Thus, by filling the lumen of the intravenous catheter with a resorbable material, components located in the puncture channel may be prevented from being carried into the vein or deeper tissue layers during puncture. If such an effect is desired, it is advantageous if the at least one resorbable material in the original state narrows or completely encloses the tube lumen of the puncture needle for the most part. Then, when the material is resorbed by fluid contact, for example by contact with blood and/or also with fluid introduced from the outside, an undisturbed flow of fluid through the needle can be exemplarily achieved.

This may also be important in other applications, such as in spinal and epidural space applications. It is therefore proposed to advantageously improve the puncture needle used in the application in the manner just described. Illustratively, the resorbable materials used may also dissolve upon contact with cerebrospinal fluid.

Materials that only dissolve upon cerebrospinal fluid contact and not upon blood contact may also be particularly advantageously used. Inadvertent traumatic administration/injection of fluids and also, for example, medicaments can thus be avoided, since the lumen of the tube of the puncture needle remains closed in one position in the blood vessel, for example in a vein, when blood comes into contact. The catheter, which is to be introduced if necessary through the interior of the puncture needle, is then not unintentionally introduced into the blood vessel. Thus, for example, undesired catheter positions in the blood vessel can also be avoided.

The puncture needle may also be composed of a grid-like, mesh-like, honeycomb-like, labyrinth-like or hole-like structure, which may comprise at least one non-resorbable material and/or at least one resorbable material. Combinations of all of the mentioned structures are conceivable.

The puncture needle may additionally be reinforced with other structures/elements, i.e. e.g. by a transversely extending, longitudinally extending or diagonally extending structure, which may comprise at least one non-resorbable material and/or at least one resorbable material. Combinations of all of the mentioned structures are conceivable.

At least one resorbable material may be embedded in the interstices of the structure. This structure can also fill the interior of the hollow spike. Metals, but also metals in the form of metal alloys or plastics or natural materials can be used as non-resorbable materials. For example carbon fiber reinforced laminates, polymers or teflon are considered as plastic materials, but also in combination with one another. Aramid fibers may also be used. The resorbable material may be a carbohydrate, but may also be another biomolecule or salt. The material may also be or comprise magnesium. Absorbable polymers, composites, bioceramic materials or biodegradable metals may also be used. The material may also be a combination of a plurality of resorbable materials and may also contain or be coated with at least one of an antimicrobial or anticoagulant or other efficacious or bioactive substance.

The resorbable material may be dissolved by blood contact or contact with other fluids and may leave behind a structure of at least one non-resorbable material. Thus, the puncture needle and/or the interior of the puncture needle may develop other properties, for example also filter-like properties. By means of the change in flow-through properties due to dissolution of the resorbable material, a filter-like structure is created which can be adapted to environmental conditions (e.g. changes in humidity) by changing the permeability.

Conventional filtration systems may also be integrated directly into the interior of the needle. The same applies to expandable materials, such as elastomers, or materials which may be composed, on a certain part or for the most part, of fibers from plants and have different strengths.

Advantageously, the puncture needle can be constructed in a lightweight construction. Light weight raw materials can be used. In particular, it is also possible to use metallic light materials such as titanium, high-strength steel, aluminum and magnesium. Plastic and fiber plastic composites can also be used.

The puncture needle can be partially, largely or completely composed of or coated with at least one material which is particularly well visible by means of ultrasound. It is also conceivable that the puncture needle comprises at least one channel in its wall, which channel is filled with a fluid, gas or steam. For this purpose, substances which are particularly well visible by means of ultrasound can be used, but for example air can also be used. The channel may be a channel extending longitudinally over part of the length, most of the length or the entire length of the needle, said channel being constructed impenetrably towards its ambient fluids, gases and vapors. However, the channel can also be formed so as to extend transversely or diagonally and completely surround the circumference of the puncture needle in part, in large part or in the sense of a ring-shaped structure. The structure may be provided multiple times at the needle. In that case, the structures may be spaced apart from each other at the same or different pitches. Thus, the distance between the structures may vary, in particular towards the needle tip. In an advantageous embodiment, the distance decreases toward the tip of the puncture needle, i.e. the structures are more closely adjacent to each other. The position of the needle tip can thereby be determined particularly well by means of ultrasound.

All other sections of the puncture needle may have the properties just mentioned, partially, mostly or completely.

The needle as described above may also be used independently of the iv cannula.

The intravenous catheter or another catheter or hose may also be constructed as described above and have the characteristics described above.

Other aspects of resorbable intravenous catheters

The intravenous catheter and/or the puncture needle may also be composed of or coated with at least one material that is resorbable/dissolvable throughout the entire length or part of the length, e.g. by contact with blood or other fluids, gases or vapors in the patient. The resorbable material may be a carbohydrate, but may also be another biomolecule or salt. The material may also be or comprise magnesium. Resorbable polymers, composite materials, bioceramic materials or biodegradable metals may likewise be used. The material may also be a combination of a plurality of resorbable materials and may also contain or be coated with at least one antimicrobial or anticoagulant or other efficacious or bioactive substance. It is contemplated that all of the components of the venous indwelling cannula are constructed of or coated with a dissolvable material.

The resorbable material initially present may provide the venous catheter and/or the puncture needle with a certain stiffness, by means of which the tip near the vein may likewise be made stiff, whereby said tip may be advanced well into the vein. Upon contact with blood, the material is resorbed, i.e. dissolved in the blood. Whereby less hard or less sharp structures may be exposed. The venous catheter can thus be made hard and then softened before introduction into the patient and in particular before introduction into the vein. Thus, the puncture needle can be acutely configured and then blunt when introduced into the patient and vein.

Puncture needle with resorbable external threads

According to an advantageous embodiment of the invention, it is provided that the puncture needle has an external thread and/or that the outer sheath has an internal thread. The external thread and the internal thread can be coordinated with each other in terms of size and pitch, so that the component with the internal thread can be rotated in a screw-like manner in the component with the external thread.

It is also possible that the puncture needle with external thread is modified by at least one resorbable material. The venous catheter may then be provided with an internal thread of at least one resorbable material matching this. It is also possible to use only non-resorbable materials. The needle and/or catheter can then be precisely rotated/screwed into the vein.

The resorbable material may be a carbohydrate, but may also be another biomolecule or salt. The material may also be or comprise magnesium. Resorbable polymers, composite materials, bioceramic materials or biodegradable metals may likewise be used. The material may also be a combination of a plurality of resorbable materials and may also contain or be coated with at least one antimicrobial or anticoagulant or other efficacious or bioactive substance.

After screwing/threading the needle into the vein, either alone or with the intravenous catheter, the resorbable material is resorbed by blood contact or other fluid contact. Thus again producing a smooth wall-like puncture needle and a smooth wall-like intravenous catheter.

The needle as described hereinabove may also be used independently of the iv cannula.

Resorbable guide wire

According to an advantageous embodiment of the invention, it is provided that the puncturing device has a guide wire which can be guided by the sheath or the puncturing needle, wherein the guide wire is composed partially, largely or completely of at least one bioresorbable material.

Conventional guide wires may be placed into a needle or intravenous catheter. The guide wire may be partially, largely or entirely composed of at least one resorbable material. The materials mentioned above may be used by way of example. The guide wire according to the invention is then at least partly resorbed, possibly so as to be left in the body. In the case of a corresponding material selection, even forgetting the guide wire or cutting off its constituent parts can no longer lead to serious complications.

The rotatability of the puncture needle around its longitudinal axis by means of a spring mechanism

According to an advantageous embodiment of the invention, it is provided that the puncture needle can be rotated about the longitudinal axis relative to the outer envelope, wherein the puncture device has a retaining element by means of which the rotatability of the puncture needle is limited or eliminated at least in a specific longitudinal displacement position of the puncture needle relative to the outer envelope.

According to an advantageous embodiment of the invention, it is proposed that the puncturing device has at least one return spring, by means of which the puncturing needle is held by spring force in a longitudinally displaced position in which the rotatability of the puncturing needle is limited or eliminated.

It is conceivable that a spring is present at the end of the venous indwelling cannula remote from the vein, which spring, in the relaxed (longer) state, holds the puncture needle in a longitudinal position preventing rotation of the puncture needle about the longitudinal axis by a holding or path limiting element arranged at the puncture needle itself and at least one further component of the venous indwelling cannula. The retaining or path-limiting element can be embodied, for example, as a cutout, groove or projection. If the puncture needle is now actively pushed with pressure in the longitudinal direction towards the vein onto at least one further component of the indwelling cannula, the spring compresses. The holding or path-limiting element of the puncture needle and the at least one further component of the venous indwelling cannula then no longer block the rotational movement of the puncture needle about the longitudinal axis, since the holding or path-limiting element is no longer snapped into each other or wedged into each other, for example. The puncture needle can now be rotated about its own axis in the longitudinal direction. If the pressure on the needle is now removed, the spring relaxes and the needle passively moves toward the user (away from the vein). The holding or path-limiting element now prevents the rotational movement of the puncture needle about its longitudinal axis again in the manner described above. For example, a "child safety device" can thereby be realized.

The intravenous catheter of the intravenous cannula may also be rotatable as just described. This may have the following advantages: a component of an occlusion/blocking by anatomical structure, such as an access port or exit port, for example, of an intravenous catheter may be rotated out of/moved away from the occluded/blocked structure without having to move the entire venous indwelling cannula or remove the entire venous indwelling cannula.

For this purpose, the venous catheter can be rotatably mounted in or at the venous indwelling cannula about its longitudinal axis. The venous catheter can likewise be transitioned at its portion remote from the vein into a structure having a larger inner or outer diameter.

The structure may likewise be rotatably supported about its longitudinal axis relative to at least one component of the venous retention sleeve. The longitudinal mobility of the structure may be given. It is also conceivable that another structure independent of the venous catheter, having a larger inner and outer diameter, is in the region in which the venous catheter transitions away from the vein into the body of the venous indwelling cannula. This corresponds to the area of the fastening element 5 and the holding element 8. The structure may reduce or completely prevent rotatability of the intravenous catheter about the longitudinal axis.

By providing a clamping element, the individual layers of the puncture system can be partially or completely fixed relative to each other, so that a safe position of the puncture system can be ensured. The clamping element can be designed as a clamping jaw with a sleeve with a conical slot and a union nut, wherein the individual layers are clamped by tightening the union nut into the inner cone of the sleeve. But the following alternatives are also conceivable:

an expansion body which is introduced into the puncture system for fixing the individual layers, wherein the layers lying inside are laminated to the outer layers by expansion of the expansion body in order to fix them.

A clip system in which the layers are fixed relative to one another by the clip being located outside the puncture system by folding over with pressure.

A screw introduced into the puncture system via a corresponding hole, wherein the screw fixes the different layers to each other by pressure by rotation.

The coating of the individual layers of the puncture system can be set up to limit the longitudinal mobility compared to conventional systems.

It is also possible to lock the individual layers into one another, for example, by means of a cutout.

The layers can be wedged into each other by: the individual layers have a diameter that is non-circular or that increases at individual locations so that at least partial fixation is achieved by rotation or pulling back and forth of the individual layers relative to each other.

The clamping element can be designed such that it fixes all layers in an untouched position relative to one another, for example by means of a spring mechanism. The fixation of the layer is removed by pressing or pulling at the clamping element and the spring is tensioned. If the clamping element is not subjected to pressing or pulling, it returns to its original position due to the spring mechanism and secures all layers to each other. The described embodiment of the clamping element has the following advantages: for example, the clamping element can be operated with only one finger.

The described function of the fixing element can be adjusted and repeated so that a great flexibility of the fixing element is ensured. In particular, the fixation element should also ensure that the puncture system can be adapted to the anatomy of the individual living beings and their individualization or to the anatomy of different body regions. The assumed subcutaneous depth of the structure to be pierced can be taken into account already before the start of the piercing process, in that the sharp portion of the piercing needle protruding from the inner, intermediate tubular body can be limited to the free length of the living being to be pierced. This also reduces the risk of inadvertent puncturing of anatomically deeper structures, especially by inexperienced users. This is an important safety aspect of the new lancing system.

The puncture needle and the intravenous catheter may also be connected to each other such that they can only be rotated together/in combination. It is conceivable that at least one friction-increasing material is present at the outer side of the puncture needle and/or at the inner side of the intravenous catheter in order to achieve said effect.

The needle and/or the intravenous catheter may preferably be adjusted to a circumference of 45 °, 90 °, 135 °, 180 °, 225 °, 270 °, 315 ° or 360 ° (illustrated in degrees with respect to the angle of the circumference of 360 degrees (360 °).

The angular specification may be identified to the user on the part of the venous indwelling cannula so that, for example, the current angle of the puncture tip or needle may be read. Circular or semicircular markings of different line widths are conceivable here, for example, and color markings of the traffic light colors "green", "yellow" and "red" are also conceivable, for example.

Marking detectable by means of an imaging examination apparatus

According to an advantageous embodiment of the invention, it is provided that at least one component of the puncturing device, in particular the outer envelope, has at least one marking which can be detected by means of the imaging examination device. There may also be multiple markings, not only at the same component of the lancing apparatus or at different components. The markers may be different or the same type of markers that may be detected by different types of imaging examination devices. For example, there may be at least one marker detectable by the ultrasound examination apparatus, and/or at least one marker detectable by computer tomography, and/or at least one marker detectable by magnetic resonance tomography. In an advantageous embodiment, the at least one marking is located in a region of the lancing device that is set up for introduction into the hollow body to be lanced, i.e. in a region adjacent to the hollow body.

According to one advantageous embodiment of the invention, it is provided that at least one component of the puncturing device, in particular the outer sheath, has at least one cavity which is filled or can be filled with air or another substance which can be detected by means of the imaging examination device. Such a cavity may for example function as at least one marking in the previously described sense. The at least one cavity may be completely tightly closed with respect to the external environment or may have at least one opening towards the environment, for example an opening towards the outside of the outer envelope. In an advantageous embodiment, the at least one opening is located in a region of the lancing device which is not designed for insertion into the hollow body to be lanced, i.e. in a region remote from the hollow body.

Supplement to puncture safety

It is proposed that at least the part of the intravenous line which is provided for being placed in the patient is made of or covered with a puncture-proof material over part of its length, its entire length or a large part of its length, over which length the puncture needle can be guided in a longitudinally displaceable manner.

Supplementing aspects of puncture-resistant hollow Selding grid lines

By means of a significantly prolonged venous catheter which is constructed in the sense of hollow puncture-proof Seldin lines, it is in principle possible to bring the puncture needle to any location of the body without risking damage to the anatomical structure passing on its way to the target structure. Such significantly prolonged intravenous catheters may also be used independently of the intravenous cannula. For example, the intravenous catheter may have a length of at least 200mm, 300mm, 400mm, 500mm, 600mm, 700mm, 800mm, 900mm, 1000mm, but may also have a length up to 2000 mm. All lengths between the dimensions are contemplated.

The venous catheter can also be used as an extraction element if the venous catheter or the hollow-wire fluid is formed impenetrably, for example with a corresponding coating or sheath, which can be made of PTFE, for example. By means of the extraction element, blood clots or other foreign bodies can be extracted from any anatomical structure, which can be reached by means of the extraction element, for example, and removed from the anatomical structure. For example, blood clots may be removed from blood vessels near the brain, near the heart, and near the extremities. A further extraction element, for example a syringe, can be connected to the portion of the hollow plug Ding Gexian formed in this way facing away from the vein, for example via a correspondingly formed connector. Connections to precisely adjustable extraction elements are also conceivable.

One aspect of the invention therefore also relates to a construction of the lancing device in the form of a hollow spiral wire with a fluid-impermeable coating, which is constructed in a particularly long manner, for example at least 1000 mm. The hollow helical wire may have a connecting element at the end remote from the patient for connecting a suction device, such as a syringe, motor-driven aspirator or the like. For example, a coronary aspirator can thereby be realized. The relatively long hollow spiral-shaped wire may be provided, for example, in a wound-up state and/or by means of a sheath consisting of a sterile sheath.

Self-closeable nature of intravenous catheters

According to an advantageous embodiment of the invention, it is provided that the outer envelope has a fluid-permeable grid-like, mesh-like or pore-like structure with small openings, which openings can be closed by the flowing-through blood component during operation of the puncturing device. Such an outer envelope with a small opening initially, i.e. in the manufactured state, allows a flow-through of a fluid, in particular blood. The opening is then automatically closed by the specific blood component deposited in the interstices of the structure, so that the outer envelope then becomes fluid-impermeable.

Resistance to an increase in pressure may also accompany this.

In the initial state, the venous catheter may also be formed from a fluid-permeable grid-like, mesh-like or hole-like structure, which may also be modified by other structures, for example structures that extend horizontally, diagonally or vertically. After introduction of the catheter, the blood component can now be deposited in the gap of the structure, whereby the intravenous catheter is fluid-impermeable. Thereby creating a venous catheter that constitutes a biological property and that can stay in the vein for a longer or permanent time.

Electrical insulation element at venous indwelling cannula

According to an advantageous embodiment of the invention, at least some parts of the lancing device have electrically insulating elements and/or electrically conductive elements, by means of which an electrically conductive connection is formed from one part of the lancing device to another part of the lancing device.

It is also conceivable that the venous indwelling cannula comprises an insulating, for example electrically insulating, element or material which, for example, can prevent heating at the venous indwelling cannula due to external influences. The element or material may, for example, enclose a sensor that may be positioned at an intravenous catheter. For example, the element or material may also enclose a spiral or wave-shaped structure and be embedded in or constitute a venous catheter together with the spiral or wave-shaped structure.

Conductive element at venous indwelling cannula

The entire venous indwelling cannula may be partially or fully composed of or coated with at least one electrically conductive material. It is also conceivable that longitudinally extending structures, for example in the form of strips, which are electrically conductive, can be stretched on or in the venous catheter.

The conductive material may be, for example, a metal or metal alloy. The following materials may be used by way of example: gold, silver, copper, brass, tungsten, aluminum, lead, stainless steel, iron, zinc, chromium, stainless steel, beryllium, platinum, nickel, titanium. Carbon/graphite may also be used.

Other embodiments of the intravenous catheter near the end of the vein

According to an advantageous embodiment of the invention, it is provided that the outer envelope has a larger outer diameter in the region close to the hollow body than in the region remote from the hollow body.

The venous catheter may be surrounded over part of its length, over most of its length or over its entire length by a pillar-shaped/cylindrical structure, with respect to which the venous catheter is also longitudinally movable. The structure may undergo a significant increase in its outer diameter toward the vein, stabilizing the needle and intravenous catheter as it is introduced through the skin and into the vein. The structure can be moved over the intravenous catheter toward the user when introducing the needle and the intravenous catheter because the structure cannot pass through the skin. The structure may also have telescoping properties. The puncture needle and the intravenous catheter may likewise be supported movably, reversibly and/or rotatably in different directions relative to the structure.

In the pillar-shaped/cylindrical structure, the venous catheter can be surrounded semi-circularly or circularly by a further structure, with respect to which it can be supported longitudinally displaceably and/or rotatably. The intravenous catheter may likewise be surrounded by a pouch-like structure. The structure surrounding the intravenous catheter may hold the intravenous catheter aseptically and may also contain, for example, antimicrobial, anticoagulant and/or friction reducing substances.

Volume increase of intravenous catheter

According to an advantageous embodiment of the invention, at least one region of the outer envelope has a material which bulges out by contact with the fluid. Such a swelling material may be, for example, an intumescent material, such as a hydrogel. As long as fluid is mentioned in this application, this includes not only liquid media but also gaseous media and vapor-like media.

Also, the intravenous catheter may be partially composed of or coated with at least one of the following materials: the material is subjected to a volume increase by blood contact or more generally by contact with a fluid, gas or vapor, or by at least one chemical reaction. Polymers, layered silicates, bentonite or composite materials comprising natural fibers may be used as examples. Proteins, fats or superabsorbents may likewise be used.

It is also possible that the venous line can also consist of or be coated with at least part of the following materials over part of its length, a large part of it or the entire length thereof: the material undergoes a volume increase by blood contact or more generally by contact with a fluid.

If the material is on the outside of the intravenous catheter, the intravenous catheter is fixed in its own position in the vein by an increase in its outer diameter, especially if another solid material on the inside of the intravenous catheter only allows for an outward volume increase of the intravenous catheter. Conversely, if the volume-increasing material is on the inside of the intravenous catheter, while there is solid material on the outside that prevents the outward volume from increasing, the inside diameter of the intravenous catheter decreases, i.e., the intravenous catheter self-occludes.

Increase of the inner diameter of intravenous catheter by blood contact

Portions or layers of the catheter may also be constructed of resorbable materials, such as being soluble in blood. The material may be a carbohydrate, but may also be other biomolecules or salts. The material may also be or comprise magnesium. The soluble material may form each arbitrary layer of the intravenous catheter. For example, if the soluble material forms an inner layer of the intravenous catheter, the inner diameter of the intravenous catheter is increased by blood contact.

Limited longitudinal mobility of the needle

According to an advantageous embodiment of the invention, the lancing device has an automatic blocking mechanism, by means of which the lancet is prevented from being pushed toward the end adjacent to the hollow body when the lancet is pulled back from the end adjacent to the hollow body by a predetermined measure.

In order to prevent the puncture needle from being re-advanced into the vein when the puncture needle has been pulled back from the vein, means for preventing this may be formed at the puncture needle. The means can be located at any point of the puncture needle, but in an advantageous development the means can be located at a point of the puncture needle which is located at a half of the puncture needle with respect to its longitudinal extension towards the user (away from the vein). In a further advantageous development, the region is formed in the rear third, the rear quarter or the rear fifth of the puncture needle, which is close to the user.

Such a mechanism is important because re-advancement of the needle toward the vein may also cause the components of the intravenous catheter to shear through the tip of the needle.

The mechanism may be configured such that at least one ramp-like structure is present at the puncture needle. The structure may be on the surface of the lancet or embedded in a recess of the lancet. The ramp-shaped structure may comprise and/or be connected to at least one spring-shaped and/or spiral-shaped structure.

If the needle is in its original position of maximum proximity to the vein prior to and during the lancing process, the structure just described is surrounded by a venous catheter or other hollow element/component of the venous indwelling cannula which lengthens the venous catheter in the longitudinal direction towards the user. Thus, the structure cannot be lifted beyond the level of the surface of the needle. A spring connected to the structure remains compressed.

Conversely, if the structure leaves the venous catheter or other hollow element/component of the venous indwelling cannula, this is caused by the relaxation of the spring: the structure is raised above the level of the needle. This occurs to the following extent: the puncture needle can now no longer be advanced towards the vein without further action, as the structure is no longer suitable for entering into the venous catheter or other hollow element/component of the venous indwelling cannula.

Instead of a ramp-shaped structure, a button-shaped or pillar-shaped structure may also be used.

It is also conceivable to use a curved structure without a spring mechanism. The curved structure may also have bimetal properties and be lifted from the surface of the needle, for example by body temperature, in such a way that the structure increases its curvature.

General Material Properties

The venous indwelling cannula may be advantageously modified, for example, by the following materials or categories of materials, substances, materials, elements, etc. (hereinafter referred to as "materials"), either alone or in combination. The listed materials are not systematically ordered here and describe not only material properties but also functional properties. Overlap, in particular also between material description and functional description, but also in terms of itself is possible. It is also clearly possible that all components of the venous indwelling cannula, individually or in combination, consist of or contain the following materials:

biocompatible metals and polymers, biopolymers,

biocompatible plastics, specifically for medical applications,

shape memory alloys such as nitinol,

copper, zinc, aluminum, iron, tungsten, manganese, silicon, magnesium, cobalt, gold, silver, bronze, platinum, palladium,

-a metal-metal alloy-metal,

stainless steel, steel alloys, in particular also stainless steel alloys,

-a non-fired stone, which is to be sintered,

functional or smart polymers, such as shape memory polymers and thermally responsive polymers,

ceramic materials, also bioceramics and textile fibre ceramics,

A silicone or a silicone elastomer,

the presence of chromium (cr),

the presence of a thermoplastic material,

the presence of a thermosetting plastic material,

elastomer, thermoplastic elastomer (TPE), TPE-a,

the presence of a polyimide (a) and,

the polyolefin is a polyolefin,

-a resin and a synthetic resin, the synthetic resin,

rubber, also specialty rubber, also EDPM,

the rubber article is a rubber-like article,

the latex is used as a matrix of the emulsion,

aramid, aramid fiber, para-aramid fiber and meta-aramid fiber,

the thickness of the cardboard sheet is chosen to be,

-a natural fiber, which is a natural fiber,

-a mineral fibre, which is a mineral fibre,

fiber composites, fiber reinforced composites and textile reinforced composites, carbon fibers, which are also capable of reinforcing composites,

the textile product for industrial use,

urethane, polyurethane, and also Thermoplastic Polyurethane (TPU),

polyester (PES),

polyvinyl chloride (PVC) materials and latex-free materials,

sand, such as quartz sand,

the presence of a wood material,

-a basalt of the type,

the presence of a fluoropolymer,

the presence of a polyurethane elastomer,

a thermoplastic high-performance plastic material, which is,

polystyrene (PS), also bulked PS,

polyamide (PA),

polycarbonate (PC),

perfluoroalkoxy Polymers (PFA),

polysulphone (PSU),

polyether block amide (PEBA),

polyetheretherketone (PEEK),

polyoxymethylene (POM),

polyphenylsulfone (PPSU),

polypropylene (PP),

polyethylene (PE), also LDPE, HDPE,

Polyetherimide (PEI),

polyethylene terephthalate (PET), polyester,

polyvinylidene fluoride, polyvinylidene difluoride (PVDF),

fluoroethylene propylene (FEP),

polyphenylene Sulfide (PPS),

polyphthalamide (PPA),

acrylonitrile Butadiene Styrene (ABS),

methyl Methacrylate Acrylonitrile Butadiene Styrene (MABS),

ethylene Vinyl Acetate (EVA), EVAC,

the presence of a polyurethane,

melamine formaldehyde resins (MF),

the polyester resin is used as a matrix material,

-a group of phosphorylcholine groups,

nylon is used as a material for the plastic film,

the flow of the teflon (r) material,

-a bentonite clay, which is selected from the group consisting of,

glass, glass fibers, glass fiber reinforced plastics,

the presence of a UV-adhesive,

PTFE, expanded PTFE, porous PTFE,-PTFE，

-ETFE，

The presence of a poly-p-xylene,

an aminoplast,

-a carbohydrate, a sugar, and a salt of a sugar,

the presence of a protein(s),

the presence of fat,

-a carbon source containing a carbon source,

the production of a non-woven fleece,

-

-felt, nonwoven fabric

-chitin.

The venous catheter may comprise at least one spiral-shaped and/or wave-shaped structure, which is composed of and/or is coated with at least one of the materials just mentioned and/or is partly, largely or completely surrounded by at least one of such materials.

The use of composite materials and layer composites is clearly feasible, and blood compatibility and anti-adhesion properties are advantageous in all materials used. Likewise, sterilization resistance and breakage resistance are advantageous. Materials with thermoplastic properties can be used advantageously, and materials visible in X-rays can also be used advantageously. UV resistance and high resistance to the effects of chemicals are sought to be achieved.

The materials may advantageously be combined such that the entire venous indwelling cannula or venous catheter is constructed puncture-resistant, kink-resistant and cut-resistant as previously described in PCT/EP 2019/057097. Fabric inserts may also be used.

The use of fibers and biodegradable materials is equally feasible. Films and laminates may also be used.

Resorbable/dissolvable materials or materials that release drugs or materials/substances may likewise be used. Thus, for example, it is possible for the material to release an antibacterial, antiinflammatory, chemotherapeutic or local anesthetic substance, to contain said substance or to be coated with said substance. This also applies, for example, to substances that act as antithrombotics, such as heparin, which can prevent the formation of blood clots at and near the venous catheter.

The surface structure and chemistry of the surface can be optimized. Hydrophilic or hydrophobic coatings may be advantageous. Super or extremely hydrophobic surfaces may also be advantageously used. The plasma cladding method can be used for production. It is also conceivable that the surface of the component of the indwelling cannula, for example the surface of the puncture needle or the intravenous catheter, is partially, largely or entirely provided with a polymer brush.

The above materials may also be used at intravenous catheters with local variation. Thus, for example, it is conceivable to use a different material at the end of the venous catheter immediately adjacent the vein than at the region remote from the vein. Thus, the tip of the intravenous catheter may illustratively be constructed of a softer material having thermoplastic properties. However, the tip of the intravenous catheter may also be intentionally designed from a harder material in order to simplify advancement into the vein.

Furthermore, at one or more sites of the venous indwelling cannula, the materials may be connected and/or transitioned into each other by a technical process. It is thus possible, for example, to connect or melt a spiral spring at the end of the venous line immediately adjacent to the vein with the material surrounding the spiral spring, either internal or external. Such joining or melting may be performed throughout the region of the intravenous catheter. Thereby, breakage of the coil spring can be prevented. Materials with suitable toughness can be used advantageously here.

Materials that expand at body temperature and/or expand in a fluid environment, i.e., increase in volume, may also be advantageously used. Thus, bentonite, for example, may be used. For example, this effect may be used at the end of the venous catheter near the vein: when introduced into the venous catheter, the venous catheter is relatively sharp at the end near the vein and is held against the needle. When the venous catheter is placed in the vein in a satisfactory manner, the venous catheter is now inflated at the end close to the vein, so that the vein wall can be less damaged. It is also possible that the intravenous catheter may be inflated over another portion or over the entire length. It is also possible that the needle may be inflated as just described to change its characteristics, such as being self-dulling and no longer pointed near the end of the vein. Hydrogels can be used.

Other arrangements, such as coil-like arrangements, are also possible.

It is also clearly feasible to use multiple layers of different materials, for example forming the walls of the intravenous catheter. The layers may be firmly connected to each other or movable relative to each other. Different aggregation states of material may exist in the wall of the intravenous catheter.

When using a suitable material, the venous indwelling cannula or a component thereof can be matched to the individualized course of the vein or the individualized anatomical representation by the user, for example by bending, prior to introduction into the patient.

Refining of the layer or surface mentioned in the previous paragraph is explicitly possible.

The material and/or the surface coating may have fluorescent properties. The material and/or the surface coating may also be discolored or more generally altered by metabolic activity, i.e. by a pathogen, such as a bacterium. However, discoloration or changes caused by the metabolic activity of the patient himself are also conceivable. Thus, for example, the residence time of the venous indwelling cannula or venous catheter can be determined and monitored.

Integrity may also be checked in the manner described. It is conceivable that the material properties of the venous catheter change in the event of a longer residence time or in the event of material defects, such as cracks or tears, in the venous catheter. Thus, for example, the conductivity may vary. If current is now applied via the conductive intravenous catheter, it can be determined whether the intravenous catheter has damage. It is also contemplated that the intravenous catheter changes characteristics that make it less visible, more visible, or appear different in the ultrasound image or X-ray image. In this context, this is also always in principle a representation of other imaging methods, such as computed tomography and magnetic resonance tomography.

Thus, periodic material examinations can be performed, especially in the case of intravenous catheters/venous indwelling cannulas which are placed in patients for a longer period of time. The dwell time can thus also be checked. It may also be of particular importance that the intravenous catheter has properties that make it less visible, more visible or appear different in X-ray or ultrasound examination in case of pathogens. Thus, for example, it can be determined whether an intravenous catheter is considered as a focus of sepsis (sepsis). Thus, unnecessary catheter changes can also potentially be avoided.

Charged materials may also be advantageously used. It is therefore conceivable that the venous catheter is charged, for example positively charged, by means of the special material properties of its outer side so as to automatically repel or move away from the inner vein wall (intima) that is more precisely negatively charged. Potential damage to the vein wall can now be avoided by reduced mechanical stimulation. Venous catheters may also be provided with low currents or low voltages from the outside, so that the effect is still enhanced or can only be achieved with sufficient strength.

Nanoparticles can also be used.

The above materials may also be used at all sections, parts and components of the iv cannula that are set up for indwelling outside the patient.

The entire venous indwelling cannula or parts thereof can be constructed in a lightweight structural manner.

Specific use as a pleural catheter

According to an advantageous embodiment of the invention, the puncturing device is designed as a pleural catheter. In this case, it is advantageous if the puncturing device or at least the outer sheath is designed to be puncture-proof and/or to be kink-proof. The puncture resistance can be achieved, for example, by means of a corresponding puncture-resistant coating or a configuration as a spiral hollow wire. The spiral hollow wire can be wound very tightly. In an advantageous embodiment, the coils of the spiral hollow wire are directly adjacent to one another without any gaps. In a further advantageous embodiment, the coils are spaced apart from one another by a maximum of 0.1mm, a maximum of 0.5mm, a maximum of 1mm or a maximum of 2mm, wherein the distance between the coils can be varied. In order to form the helical hollow wire further in a puncture-proof manner, at least one further puncture-proof material may be present between the coils. The puncture resistance of the material here relates to the possible puncture of the pleural canal by puncturing, which is to be prevented by the puncture-resistant material. The puncture-resistant material may be a metal, also in the form of a metal alloy, or a correspondingly puncture-resistant plastic material or a natural material. For example carbon fiber reinforced laminates, polymers and/or teflon are considered as plastic materials, but also in combination with each other. Aramid fibers may also be used.

By means of the puncture resistance, it is ensured that parts of the puncturing device are not pierced or sheared by the penetration of a conventional puncturing needle. By virtue of the anti-kink property, it is ensured that unintentional kinking of the puncturing device does not occur when the puncturing device is used in accordance with the requirements.

In a design as a pleural catheter, the catheter system is designed such that it can be used to puncture the pleural cavity, for example in the case of a pathological accumulation of gas, steam or fluid in the pleural cavity (e.g. pneumothorax, haematoma, pleural effusion). The gas, vapor or fluid may then be expelled from the pleural cavity by means of a catheter system. In such applications, the puncture needle (in such applications a pleural puncture needle) is also guided through a catheter (in such applications a pleural catheter) surrounding the puncture needle. The catheter may be constructed here as described in the present patent application and as described in PCT/EP 2019/057097.

Advantageously, the pleural catheter has a stitch length of at least 50mm, such as 80mm, 85mm, 90mm, and 140mm greater. However, the pleural catheter may also have a stitch length of up to 160mm, 180mm, 200mm or 600 mm. The pleural puncture needle and the pleural catheter and the entire catheter system are here in total considerably prolonged. The needle track length of the pleural catheter is here the length corresponding to the length of the pleural catheter in the patient. The stitch length may also be less than 50mm for use in a particular patient population, such as children. All lengths are contemplated. The outer diameter of the pleural canal may be 2mm-5mm, in an advantageous embodiment 3mm-4mm. The inner diameter of the pleural canal may be 1mm-4mm, in an advantageous embodiment 1.5mm-3mm. All dimensions are conceivable.

All the configurations/features just mentioned can also be used in and at a generic puncture system, for example also in and at an iv cannula.

Other applications

In an advantageous embodiment/development, the venous indwelling cannula is a catheter system for invasive measurement of arterial blood pressure.

In an advantageous embodiment/development, the venous indwelling cannula is a universal vascular catheter system that can be used for all blood vessels. In that case, the catheter system may be provided with a marking system, which alternatively may comprise the elements/colors "blue" and "red". Here, "blue" represents a venous position, and "red" represents an arterial position of a catheter in a corresponding blood vessel.

In an advantageous embodiment/development, the venous indwelling cannula is a catheter system for puncturing the trachea.

In an advantageous embodiment/development, the venous indwelling cannula is a catheter system for puncturing the bladder.

In an advantageous embodiment/development, the venous indwelling cannula is a catheter system for puncturing the gastrointestinal tract and/or the abdominal cavity.

In an advantageous embodiment/development, the venous indwelling cannula is a catheter system for a puncture reservoir, pump, hose, tube and port system.

In an advantageous embodiment/development, the venous indwelling cannula is a catheter system for use in the field of interventional radiology.

In an advantageous embodiment/development, the venous indwelling cannula is a catheter system for use in the field of interventional cardiology.

In one advantageous embodiment/modification, the venous indwelling cannula is a catheter system for use in the field of emergency, disaster or tactical and military medicine.

Thumb piece

The venous indwelling cannula may have at least one retaining and/or connecting element (hereinafter simply "retaining element") for facilitating application to a patient, wherein the retaining element has a complementary shape or negative profile of a human thumb or a human fingertip. Thus, the venous indwelling cannula can be improved ergonomically and advantageously for the user.

In particular, the holding element can also be formed in a curved/arcuate manner. For example, the holding element can be configured convexly towards the vein and concavely towards the user. However, it is also possible for the holding element to be configured concavely toward the vein and convexly toward the user. It is also conceivable to form it in a curved/arcuate manner only on the side facing the user and in a straight manner on the side facing away from the user. Also, the side facing the user may be provided with at least one cut, flattened and/or groove to accommodate the user's fingers, fingertips and/or nails.

In this case, the one-hand operability of the venous indwelling cannula can be simplified, since the user's finger, for example the index finger, can safely push the connecting element and the venous catheter connected thereto toward the vein. The holding element may, but need not, be configured such that an extraction element, for example a syringe, may be connected. The holding element may also be embodied, for example, cylindrically, pillar-shaped or plate-shaped, or also in the form of a polygon, and only on the side facing the user, as described above.

The holding element may also be partially or completely rotatably arranged at other parts of the venous indwelling cannula.

The connecting element may also be arranged at other parts of the venous indwelling cannula in a manner that is reversible to one, two or more sides, either partly or entirely.

The connecting element may also be arranged partially or completely movably in the longitudinal direction at other parts of the venous indwelling cannula.

The connecting element can be composed of or coated with at least one material on its upper side, which is characterized by an increased frictional resistance. Illustratively, the surface structure may be grooved or convex. The surface structure may likewise have adhesive or cohesive properties and/or be provided with a removable protective film.

The plastic deformability of the holding element can likewise be given. The deformable material may also be partially or completely decoupled from the other components of the iv set cannula.

The connecting element may likewise comprise a coupling element. Via the coupling element, the connecting element can be detachably connected to other components of the venous indwelling cannula. The coupling element can also be embodied in the form of a plug connection. The connecting element can likewise be connected detachably or inseparably to the 2 nd connecting element. It is also conceivable that the connecting element is also only partially formed, in particular toward the user, in the manner just mentioned.

The improvements mentioned above have the following advantages: the venous indwelling cannula no longer has to be held in the vicinity of the venous catheter, thereby reducing the risk of contamination by pathogens.

It is also conceivable that the connecting element has a flat, stretched internal channel which is connected to the venous catheter at a flat angle. The height of the connecting element can thereby be reduced. It is then possible to place the extraction element via the connection element onto the venous indwelling cannula at an acute angle with respect to the longitudinal axis of the venous catheter. For example, the infusion line may likewise be secured to the iv cannula at the acute angle just described. Another hollow extension element through which fluid can flow can be dispensed with. For example, an acute angle has the following advantages: no holding and/or extraction element protrudes steeply upwards from the iv catheter. For example, an acute angle has another advantage: the extraction element and/or infusion line need not be attached directly to the venous indwelling cannula near the skin, which may cause contamination of the attachment site by pathogens.

The connecting element may have an internal and/or external thread and is compatible with, for example, an extraction element and/or a connecting element of an infusion line, which may likewise comprise a thread-like structure.

Removable layer of intravenous catheter/hollow structure

According to an advantageous embodiment of the invention, it is provided that the outer envelope is formed in multiple layers with one or more removable layers.

Intravenous catheters may also be constructed with one or more removable layers. If the layer is removed, the inner diameter of the intravenous catheter or the lumen of the tube increases. In this way, the layer of the venous catheter which is populated with germs or is provided with blood clots can be removed simply. It is also possible to introduce layers from the outside in the manner described so that the venous catheter can be supplemented with other layers. Hollow structures may also be used, which may be introduced into the venous catheter and replaced periodically. The hollow structure may be matched to or matched to the respective inner diameter and geometry of the intravenous catheter. However, the hollow structure may also constitute a geometry that differs from the geometry of the intravenous catheter. The hollow structure may be constituted by at least one layer. The at least one layer may have antithrombotic, antibacterial and/or puncture-resistant properties. The hollow structure may also have a spiral or wave-shaped surface and be modified with a sealing coating, such as a PTFE coating.

Other constructions of venous catheters

It is also conceivable that the intravenous catheter comprises a fish-scale or roof tile-like structure, which is arranged, for example, overlapping or superposed.

The venous line can also be constructed in a similar manner to commercially available shower hoses, and can also be constructed as a braided hose. Intravenous catheters can be advantageously improved by different braiding types. For example, different spiral braids are conceivable, which may be made of stainless steel or another metal or metal alloy. Flat braids, core-shell braids, or encapsulated braids are also contemplated, possibly in modified forms. However, the braid may also be composed of, or coated with, any other material, particularly puncture-resistant and cut-resistant materials. Configurations of intravenous catheters with metallic fabrics, expanded grids or expanded metals are also contemplated.

The venous catheter may also have a honeycomb, grid or pore structure. The venous catheter can also be constructed with a multi-dimensional tissue structure.

The intravenous catheter may additionally be reinforced with a longitudinally extending structure. The longitudinally extending structure may be provided over part of the length, most of the length or the entire length of the intravenous catheter, or only in the region of the intravenous catheter close to the portion of the vein. For example, the longitudinally extending structure may help to advance the intravenous catheter into the vein during introduction, and for example stabilize an inserted, rather flexible, intravenous catheter so that the intravenous catheter does not press against the vein wall through blood flow.

The venous catheter can also be configured as a constriction tube or be covered with such a constriction tube. The shrink hose may be a PTFE hose. The venous catheter can also be constructed as a multi-layer hose.

The venous catheter may be a rubber hose or a rubber tube.

Three-way cock/filter

The venous indwelling cannula may already contain at least one integrated three-way stopcock or multi-way stopcock system, which may be detachably or inseparably connected with the venous indwelling cannula, respectively. In particular, the three-way stopcock or the multi-way stopcock system may be inseparably connected to a hollow elongate member that is connected to the intravenous catheter towards the user. The three-way tap can also be configured as a three-way tap with a hose. The at least one filter element can be connected to the at least one component of the venous retention sleeve in a detachable or non-detachable manner, in particular also to the hollow elongate element.

Other embodiments of the spiral/wave-shaped structure

According to an advantageous embodiment of the invention, the wall of the outer envelope has at least two spiral or wave-shaped structures, in particular a spiral or wave-shaped structure directed towards the inner side of the outer envelope and a spiral or wave-shaped structure directed towards the outer side of the outer envelope.

The wall of the intravenous catheter may also be formed by at least a double spiral or wave-like structure, or at least two spiral or wave-like structures are in the wall of the intravenous catheter.

The structures may be inseparably connected to each other, but may also be not connected to each other as determined by the structure. In the latter case, the structures may be movable relative to each other, e.g. movable in the longitudinal direction or rotatable/rotatable relative to each other. This has the following advantages: the venous catheter maintains its flexibility so that it can be matched to venous stretch, but is still more robust/sturdy to construct.

In particular, it is also conceivable for the second spiral-shaped or wave-shaped structure to be inserted into and/or engage into a recess of the first spiral-shaped or wave-shaped structure. The structures can be moved relative to one another, but their movability relative to one another can also be limited by at least one material and/or a coating which increases the frictional resistance. The limitation of the movability with respect to each other can also be performed in the following manner: other connection means or structures, such as micro-structures or nano-structures, exist between two spiral or wave-shaped structures.

Combinations of at least one helical or wavy structure and at least one braid-like structure are also conceivable. The undulating surface is represented by alternating diameters of the intravenous catheter at least in a cross-section along the longitudinal axis of the intravenous catheter. The waveform shape may be formed, for example, by sinusoidal oscillations, square oscillations, triangular oscillations and/or sawtooth oscillations.

The outer diameter of the at least one helical structure may vary over the length of the intravenous catheter. In particular, the outer diameter may decrease towards the vein. However, it is also conceivable that the outer diameter is larger in the region of the venous catheter which is subjected to mechanical special loads, for example where the venous catheter is connected to other components of the venous indwelling cannula and/or is guided through the skin of the patient after abutment, than in other regions. The spiral structure is advantageously formed correspondingly over a length of 1mm to 20mm, in particular also over a length of 2mm to 10 mm. The outer diameter can be increased here by at least a factor of 1.5, but can also be at least doubled.

Thus, in combination with a change in the density of the windings, a flexible but at the same time also robust and adaptable venous catheter to different given conditions, for example anatomically given conditions, can be achieved.

The spiral or wave-shaped structure may be composed of nitinol, stainless steel, aramid and/or at least one hard plastic material over part, most or all of its length or have a corresponding coating.

The helical or wave-shaped structure may be made of magnesium material over part, most or all of its length or have a corresponding coating containing magnesium. Thus, the structure can obtain the characteristic of reabsorption. In particular, structures that stabilize the longitudinal, transverse or diagonal stretch of the intravenous catheter during its introduction into the vein may also contain magnesium. Then, after introducing the intravenous catheter into the patient, the structure may be resorbed, for example, by blood flow.

Thus creating a venous catheter that is hard to construct and then softer when introduced into a vein. Alternatively or additionally, in addition to, but independently of, using a spiral or wave-shaped structure, the venous catheter may be coated with a corresponding material at the inner and/or outer side. However, if such a structure is used, the structure may also be completely surrounded by at least one material comprising magnesium.

It is also conceivable that the venous catheter and all other components of the venous indwelling cannula are at least partly composed of magnesium material or have a corresponding coating comprising magnesium.

The spiral-shaped structure may be constructed of at least one material that expands at body temperature as compared to room temperature. Thus, upon warming to body temperature, for example, upon placement of an intravenous catheter in a vein, a tighter wrap of the spiral-shaped structure and thus a change in flexibility may be achieved. Then, an intravenous catheter comprising a spiral-shaped structure may become stiffer, for example, after introduction into a vein. The material may be, for example, a metal or may be in the form of a metal alloy. In particular, the material may be aluminum. In general, consider all materials listed in the section "general material properties" above.

The same effect can be achieved if at least one material having swelling and/or hygroscopic properties is used. For example, the material may be or comprise bentonite, hydrogel or starch.

It is also conceivable that the winding of the spiral-shaped structure is hollow internally over part, most or all of the length of the spiral-shaped structure. There may be a fluid or gas/vapour in the cavity that expands as the ambient temperature increases, for example again from room temperature to body temperature. The cavity may be connected to at least one channel to which the extraction element may in turn be selectively connected, for example via a connector. The cavity of the spiral-shaped structure can thus be filled by the user with a fluid, gas or steam, for example by means of a suction element. Likewise, the fluid, gas or vapor may again be expelled from the cavity. Advantageously, a valve element can additionally be used, which prevents the fluid, gas or vapor from possibly flowing out of the cavity via the channel if the extraction element is not mounted on the connector.

However, it is also conceivable to modify the winding of the spiral structure by means of a plurality of cavities which are separated from one another by the structure and thus do not communicate with one another. In this case, the non-communicating cavities may be connected to different channels to which the extraction element may in turn be selectively connected, for example via a connector. The valve-like element may be advantageously applied as just described.

The spiral-shaped structure may be composed of at least one material having elastic properties. Depending on whether the spiral-shaped structure is filled with a fluid, gas or vapor as just described, it can therefore expand or contract, i.e. its volume can also be varied independently of the ambient temperature prevailing.

Therefore, the volume of the spiral structure can be precisely controlled according to the filling amount. This may directly have an effect on the characteristics of the intravenous catheter.

The spiral-shaped structure thus constructed may be located in the wall of the intravenous catheter and separated inwardly from the lumen of the intravenous catheter by the inelastic layer. Thus, when delivering fluid, gas or vapor, the outer diameter of the intravenous catheter increases without the diameter of the lumen of the tube changing.

The spiral-shaped structure thus constructed may be located in the wall of the venous catheter and may also be separated outwardly from other structures of the venous catheter or the vein itself by a non-elastic layer. Thus, upon delivery of a fluid, gas or vapor, the diameter of the lumen of the tube is reduced without the outer diameter of the intravenous catheter increasing.

This results in a venous line which can be optimally adapted to the individual vein trend and also, for example, the vein diameter which increases toward the heart.

The improved intravenous catheter as described hereinabove may also be used as a hose for other applications, independent of the iv cannula. The intravenous catheter can thus be used, for example, as a hose for other catheter systems or as a breathing hose, for example also as an endotracheal tube. The puncture needle may also have the characteristics just mentioned.

Special construction of venous catheters in mechanically stressed skin areas

According to an advantageous embodiment of the invention, it is provided that the outer jacket has one or more reinforcing elements in each case in one or more regions subjected to increased mechanical loading. Such reinforcing elements can be configured, for example, as support structures.

An accordion-shaped, spiral-shaped or wave-shaped embodiment of the venous catheter is also conceivable only at points of special mechanical loading, for example where the venous catheter is at the skin level and transitions away from the vein into other parts of the venous indwelling catheter. In this case, a special embodiment of the venous line can be advantageous over a section of 1mm to 20mm, in particular over a section of 2mm to 10 mm. The intravenous catheter may also be reinforced with other structures or elements only over the length. Over the length, the venous catheter may also be reinforced, for example, by other layers or protective sleeves. The protective sheath may enclose the intravenous catheter basin, semi-circle, or circle over a portion of its length. The intravenous catheter may be inseparably connected to the protective sheath. It is also conceivable that the intravenous catheter is guided in the protective sleeve in a longitudinally movable and/or rotatable/rotatable manner. Potential material damage, such as breakage, at the intravenous catheter can be prevented by the protective sheath.

It is also possible to make a very flexible connection in the just mentioned areas. Additional connectors may be used. A flow guiding element may also be used, which continues into the venous catheter towards the vein and may be rotated or bent. The guide element can be rotated or bent freely in all directions. Such a flow guiding element can also be formed in a hinge-like manner, for example in the manner of a spherical hinge or in the manner of a hinged hinge.

The venous line can also be guided through a hinge-like, for example spherical hinge-like, or hinge-like structure which partially or completely surrounds the venous line in the region just mentioned. The venous line can be guided through the structure in an internal manner and be partially or completely enclosed by the structure.

The venous catheter may also be held by a structure that is externally applied to the venous catheter, which structure may be partially, largely or completely applied to the venous catheter, whereby the venous catheter is not bent. The external structure may in particular be formed in a basin-shaped, semi-circular or circular shape, and may also be part of or combined with the hinge-like structure as described hereinabove.

The connecting element may also be connected with other components of the venous indwelling cannula via the hinge-like structure described hereinabove. The flow guiding structure may be guided through the structure in an internal manner.

Settable flexibility of intravenous catheter

According to an advantageous embodiment of the invention, it is proposed that the puncturing device has at least one adjusting element, by means of which the flexibility of at least one region of the outer envelope can be adjusted by the user.

The tubular structure can be inserted into the wall of the venous catheter, i.e. the outer jacket, in the cavity, said tubular structure being supported in a longitudinally movable manner relative to the other wall components and in a rotatable manner about the longitudinal axis of the venous catheter. The cavity can be closed towards the vein and opened towards the user. Instead of being completely circular, a tubular structure, which may also be embodied, for example, in a semicircular manner, may also extend beyond the venous line in the longitudinal direction. In particular, the tubular structure can protrude in the longitudinal direction out of the venous catheter and the extension element present towards the user, which tubular structure can likewise be located in the venous catheter or its wall as just described. Thereby, the structure can be controlled in its position by the user.

Thus, the flexibility and rigidity of the intravenous catheter in the blood vessel can be individually changed by the user. This is especially important when the intravenous catheter has not yet reached its final position in the vein. Thereby creating a new set of catheter systems.

If the tubular structure is also constructed in a puncture-proof manner, it is possible to move the venous line relative to the puncture needle in all directions also a plurality of times relative to one another without damaging the venous line. The tubular structure may be formed of or coated with at least one puncture-resistant material. The puncture resistance of the material here relates to a possible puncture of the venous catheter by the puncture needle, which should be prevented by the puncture-resistant material. The puncture-resistant material may be a metal, also in the form of a metal alloy, or a corresponding puncture-resistant plastic material or natural material. For example carbon fiber reinforced laminates, polymers and/or teflon are considered as plastic materials, but also in combination with each other. Aramid fibers may also be used.

Due to the above-described properties of the venous indwelling cannula, it may also be possible to leave the puncture needle pulled back into the venous catheter first in order to re-puncture, for example, a structure that is deeper at a later time. The puncture needle which is pulled back far enough into the venous line is surrounded by the external puncture-proof venous line and cannot damage the surrounding structures.

Applicator at a portion of a venous catheter near a vein

According to an advantageous embodiment of the invention, the piercing device has an applicator at the end adjacent to the hollow body for applying the substance in the region of the penetration site of the piercing needle at the hollow body. For example, the applicator may be configured as a liquid-tight hollow body, such as a bag, filled with an antimicrobial liquid or other fluid. For example, the antimicrobial liquid may be an alcoholic, iodinated, or other sanitizing liquid. The fluid may illustratively have friction-reducing, antimicrobial, local anesthetic, and/or anticoagulant properties. For example, a cooling medium, such as a cooling liquid and/or ice, may also be included in the applicator in order to cool the region of the penetration site of the needle. Thus, the use of the lancing device in living beings can be designed with less pain. The applicator can in particular be designed such that it cannot penetrate the sheath of the hollow body to be pierced, i.e. it should not be designed too sharply in the region close to the hollow body, but rather be designed blunt.

There may be another structure, i.e. an applicator, which partly or completely encloses the intravenous catheter and/or the puncture needle before introduction into the patient. The structure may be a closed hollow body that is longitudinally movable relative to the intravenous catheter. For example, the structure may be cylindrically formed with a circular or oval cross-section, or may be in the form of a rod, nozzle or tube. The structure may also be square. The structure may also be modified, for example, in the form of an applicator, sponge, foam or gel ring, bag or capsule. The structure may also be formed in a disk-like, hat-edge-like or ramp-like manner.

The structure may also be configured such that at least a portion of the hollow body is in front of the tip of the puncture needle in the longitudinal direction. It is advantageous if the hollow body is surrounded by a wall which can be pierced by the piercing needle tip. The wall may also be a membrane. If fluid is now present in the hollow body, the needle and intravenous catheter are wetted with fluid prior to introduction into the vein. The fluid may illustratively have friction-reducing, antimicrobial, local anesthetic, and/or anticoagulant properties.

The structure in front of the needle tip prior to application of the venous indwelling cannula also has the following advantages: the structure provides puncture protection to the patient and the user until placed on the patient's skin.

In an advantageous development, the outer diameter of the structure surrounding the venous catheter is at least 1.5 times greater than the outer diameter of the venous catheter. In a further advantageous development, the outer diameter is at least 2 times greater than the outer diameter of the venous indwelling cannula. In a further advantageous development, the outer diameter of the structure is at least 3 times, at least 4 times, at least 5 times and at least 6 times greater than the outer diameter of the venous indwelling cannula.

The structure surrounding the intravenous catheter may taper towards the end near the hollow body, for example at an angle of at least 30, 45, 60, 75 or 90 degrees, based on a 360 degree system. The angle relates to the angular measure between the two outwardly inclined expansion surfaces of the structure and not to the midline of the structure.

Thus, the structure cannot penetrate the skin when the needle and venous catheter are introduced through the skin. Due to its longitudinal mobility, the intravenous catheter is wetted with the fluid described above over most or all of its length. After the wetting process, the structure may remain at the venous catheter and may at least partially protectively surround the venous catheter, for example in a region of transition away from the vein in other components of the venous indwelling cannula. The structure may be a "sleeve" that is initially "in front of" the intravenous catheter, then "slips back" at the intravenous catheter when it is introduced (and wets the intravenous catheter here), and then protectively encloses the intravenous catheter to the entry area in the skin (minimizing the risk of infection).

It is also contemplated that the structure may be removable from the intravenous catheter and configured, for example, to be rupturable or tearable.

The structure may additionally be provided with an attached or adhesive surface to stabilize the iv cannula on the skin during penetration.

It is also contemplated that the needle and/or catheter may be guided through the structure already before the puncturing procedure is initiated. Thus, the structure may partially or completely enclose the puncture needle and/or the intravenous catheter. The walls of the cavity of the structure may be disposed in a longitudinally movable and fluid-tight manner at the puncture needle and/or the intravenous catheter.

It is also conceivable that the cavity of the structure is at least partially surrounded by at least one further cavity, which is separated from the first cavity by an additional wall. Likewise, at least one further cavity may be adjacent to the first cavity and may likewise be separated from said first cavity by a wall. Thus, the intravenous catheter may be wetted with different fluids which, although used in a compatible manner on the intravenous catheter, must be stored separately from one another prior to use.

It is also conceivable that urea is present in one cavity and water is present in the other cavity. Other materials used in commercial quick frozen ice bags may also be used. In this way, the puncture needle and/or the intravenous catheter can be cooled before and upon introduction into the patient, and thus the puncture needle and/or the intravenous catheter can be introduced into the anatomical structure with low pain.

Capillary, porous and/or honeycomb structures, for example also in the form of sponges, can also be present in the cavity, which structures have direct contact with the venous line and ensure not only wetting of the venous line with fluid but also mechanical cleaning and/or drying of the venous line. It is also conceivable that at least one cavity of the applicator may be filled with fluid from the outside, for example also by a bacterial filter. The above structure can then ensure uniform filling of the cavity with fluid, as well as a sustained release of fluid onto the intravenous catheter.

Intravenous catheter as a construction solution for a pigtail catheter

According to an advantageous embodiment of the invention, it is provided that the lancing device has the following mechanism: by means of said mechanism, the outer envelope can be converted into a spiral configuration by a relative movement with respect to the puncture needle. The outer envelope can initially have a non-spiral configuration, for example an elongated, rectilinear configuration. The puncture needle can be guided through the outer sheath thus configured. The outer sheath may be converted into a helical configuration by pulling the outer sheath back relative to the outer sheath and/or advancing the outer sheath relative to the needle.

The venous catheter may also be configured in a curled shape at the end immediately adjacent the vein. However, unlike braided catheters used in medicine, the catheter is not initially stretched by an implanted guide wire, but rather by an implanted puncture needle. The intravenous catheter transitions from a straight extension to a curled or at least curved extension as soon as the intravenous catheter is advanced towards the vein beyond the tip of the puncture needle, or the puncture needle is pulled back from the intravenous catheter. The intravenous catheter may illustratively be constructed of silicone or polyurethane, but may also comprise at least one shape memory alloy, such as nitinol or nitinol copper. Combinations of copper, aluminum, nickel and zinc are also contemplated. The embodiment with at least one shape memory alloy can also be present only in the region of the venous catheter which is to be transitioned into a curled or at least curved stretch. The region of the intravenous catheter may also comprise a spiral or wave-shaped configuration. However, it is also possible that a spiral or wave-shaped structure no longer exists in the region of the venous catheter, but rather forms a region of the venous catheter which remains straight.

The recess/opening may be provided over the entire length of the intravenous catheter, but is preferably also provided at the site of greatest bending or flexing of the intravenous catheter. The liquid to be infused thereby continues, for example, into the blood vessel in a flow direction away from the venous catheter.

The venous indwelling cannula thus improved may be used in particular in the field of urosurgery, but may also be used for pneumothorax drainage, especially also in the case of premature infants/newborns.

Communication of lumen within intravenous catheter

According to an advantageous embodiment of the invention, the outer envelope is formed as a multitube lumen, wherein two or more tube lumens can be connected to one another via one or more openings. Such different tube lumens are typically separate from each other. However, through such openings, fluid communication between two or more tube lumens may be locally permitted.

In the embodiment of the at least two lumen of the venous indwelling catheter, in particular, the separation between the lumen of the tubes can be partially or largely eliminated within the venous catheter. This can be achieved by means of recesses which are placed in a structure separating the tube lumens from each other. For example, the recess may have a circular or oval configuration, and may also be provided with a flap-like configuration that allows fluid flow in only one direction. Furthermore, elements which perform the function of the overflow valve may be present in the recess.

The recess may likewise have a filter-like structure which only allows certain fluid components to pass through the recess. It is also conceivable for at least one lumen of the venous catheter to partially or completely transition into another lumen. The tube lumen may also terminate blind and be a sort of dead-end or reservoir, such as a reservoir for medication. The blind ended tube lumen may also contain at least one sensor.

It is also conceivable that the structure separating the tube lumens within the intravenous catheter from each other comprises externally adjustable elements via which it is possible to influence: whether fluids can communicate with each other in the initially separate tube lumens. This can also be done in the following way: at least two tube lumens within the intravenous catheter may rotate about a longitudinal axis or move in a longitudinal direction and contain complementary recesses relative to each other. If the recesses are now placed one above the other by a corresponding movement, fluid can flow between the different tube lumens; otherwise the fluids would be strictly separated from each other.

Thus, it is also possible at any time to access at least one further lumen within the intravenous catheter for one lumen, if necessary to increase the flow rate: i.e. when said flow rate is decisive and not when at least a second separate tube lumen is present.

The separate tube lumens can be separated from each other by at least one wall having a spiral/wave-shaped or mesh, braid-shaped or grid-shaped surface and improved by means of a sealing coating, for example a PTFE coating. Combinations with transversely extending, longitudinally extending or diagonally extending structures are conceivable, which can also ensure the desired stability of the tube lumen wall alone. In an advantageous development, the recess is surrounded by a structure, which may also be formed as a wire structure, for example a ring structure, which stabilizes the shape of the recess and keeps it open.

The venous catheter thus constructed can also be used independently of the venous indwelling cannula, for example as a midline catheter, central venous catheter (ZVK) or dialysis catheter.

Automatic propelling mechanism of intravenous catheter

According to one advantageous embodiment of the invention, it is provided that the puncturing device has a self-propelled mechanism by which, if necessary in dependence on at least one external condition, a self-propelled movement of the outer sheath into the punctured hollow body is produced through the opening realized by means of the puncturing needle.

The following mechanisms may be present here: the mechanism ensures that the intravenous catheter automatically advances beyond the needle toward the vein as the needle or catheter is retrograde through the patient's blood during the lancing process. For example, the mechanism may be or include a spring mechanism.

It is conceivable that the spring mechanism is triggered by heat of a fluid, e.g. blood, flowing back through the venous catheter towards the user, but also by heat of gas or steam. The flow guiding component of the venous indwelling cannula, such as the venous catheter itself or a hollow elongate element or lumen 7 attached to the venous catheter towards the user, may be constructed of or comprise a bimetal.

The bimetal may be coupled with a path-defining element that is in contact with the path-defining element of the venous catheter and prevents advancement of the venous catheter toward the vein in a resting state without warming.

If now warmed fluid, such as blood, flows near the bimetal, the bimetal bends. The bimetal can be bent here in the following manner: the bi-metallic path-defining element is moved away from the path-defining element of the intravenous catheter.

This effect now happens to occur if the intravenous catheter now naturally tends to advance towards the vein due to the spring coupled thereto. Depending on the prestress of the spring, the pushing takes place more slowly or more rapidly. The propulsion can also be varied in its speed or completely hampered by another manual operating element.

When advanced slowly, the fragile vein can be gently punctured, for example. Another advantage is that the venous indwelling cannula which constitutes the mechanism just described can be operated with one hand. Furthermore, the undesirable movement of the venous indwelling cannula is suppressed to a large extent by the user. The user may be fully focused on stabilization of the iv set cannula on the patient. This minimizes the risk of the necessary components of the venous indwelling cannula, in particular the puncture needle tip and the venous catheter, falling out of the vein again during the puncture procedure, since less manipulation of the venous indwelling cannula is now required in the critical phase.

Instead of the bimetal described above, at least one material which undergoes a volume change, e.g. a volume increase due to expansion, upon fluid/blood contact may also trigger the effect just described.

It is also conceivable that at least one structure composed of at least one resorbable material holds the tensioned spring under pressure and thus in place. Such a spring may be illustratively located between the needle and the intravenous catheter and connect them to each other. However, the spring may also be connected to the puncture needle alone or to the venous catheter alone. However, it is also conceivable that in the section of the venous indwelling cannula that is farther away from the vein, the spring is not firmly connected to the puncture needle or the venous catheter, and that in the event of a change of state the spring can either push the puncture needle or the venous catheter towards the vein.

If blood or other fluid now flows into the intravenous catheter, the resorbable structure dissolves and the spring undergoes a state change, such as an increase in the length of the spring. The spring now ensures advancement of the venous catheter towards the vein.

In the case of a backflow of blood through the components of the venous indwelling cannula, a flap, valve or clip mechanism can also be activated, which ensures that the force is diverted or controlled such that the venous catheter is advanced from there in the longitudinal direction beyond the puncture needle toward the vein. This may also be important, for example, when puncturing an artery in which there is a higher pressure than in a vein.

It is however also possible that the puncture needle itself is pushed away from the vein in the longitudinal direction towards the user by a backflow of blood into the puncture needle and/or the venous catheter. For this purpose, the puncture needle can be advantageously modified in its hollow, i.e. with its interior lumen, by means of flap-like, wing-like or valve-like or other elements that increase the flow resistance. The elements can also be adjusted in the following sense: i.e. the element protrudes into the lumen of the tube, i.e. moves away from the wall of the lumen of the tube, by blood flowing back into the needle. Typically, an externally located intravenous catheter is advanced into the vein via an internally located puncture needle. Here, the venous indwelling cannula is typically operated with 2 hands, and unavoidable "jerking" of the venous indwelling cannula occurs. The "bump" may cause the venous catheter to slip out of the vein and, especially in the case of small veins, has compromised puncture success. This can be avoided by the previously described design of the lancing device.

If now blood flow from the vein hits the structure, the needle is pushed away from the vein towards the user when the user is not gripping the needle. In order to eliminate the need for the user to do so when introducing the venous indwelling cannula into the patient, other fastening and retaining elements may advantageously be provided on or at the venous indwelling cannula.

In principle, the element may also be on the outside of the puncture needle or at the inside of the intravenous catheter surrounding the puncture needle. In the latter case it may be advantageous for the element to interact with other elements on the outside of the puncture needle.

Venous catheters or lancets can also be passively floated into the vein by blood flow. In this case, it may be advantageous if the structure is then not connected to other elements of the venous indwelling cannula. It is also conceivable that the venous negative pressure that potentially exists in some veins causes the venous catheter to be pulled into the vein in the longitudinal direction as well. The advantage is that in the intended venous position of the venous catheter, it is then no longer possible to introduce the venous catheter undesirably into the artery, since there is a higher pressure.

The float-in can also be triggered if the hollow extension element described in PCT/EP2019/057097 is flown through by the patient's blood. It is possible here for the blood flow to be accelerated by a negative pressure element. For this purpose, a vacuum effect can be used.

Prevent polluting vein and keep somewhere sleeve pipe when connecting syringe or infusion line

According to an advantageous embodiment of the invention, the lancing device has a contamination protection device for protecting the end of the lancing device remote from the hollow body from contamination. In particular, the connection for connecting other elements, such as a hose, to the lancing device can thereby be protected from contamination. The pollution protection device may for example have an external protection structure.

In connection with the extraction element or other elements via which fluid or medicament can be provided, it is in any case necessary to prevent contamination of the flow guiding element (hereinafter simply referred to as "element") at the chamber 7 and/or the venous indwelling cannula in the area of the connection element 9 by pathogens, for example by the user's hand or the patient's skin.

This can be solved in the following way: a flow guiding element, for example a cylindrical element, located outside the patient remote from the vein is surrounded in part or completely by at least one further protective structure each. The outer protective structure protrudes in the longitudinal direction towards the extraction element. In an advantageous embodiment, the outer protective structure extends in the longitudinal direction over the flow guiding element by 1 mm to 5 mm, but it can also extend in the longitudinal direction over the flow guiding element by 6 mm to 10 mm or also over the flow guiding element by 10 mm. The flow guiding element may also be constructed, for example, in the form of a three-way tap.

The flow guiding element may be guided in a longitudinally movable manner through the outer protective structure. It is likewise possible to apply only the outer protective structure to the flow guiding element in a longitudinally movable manner or to partially or completely enclose the flow guiding element.

The flow guiding element may be guided through the outer protective structure in a rotatable manner about the longitudinal axis. It is likewise possible to apply only the outer protective structure rotatably about the longitudinal axis to the flow guiding element or to partially or completely enclose the flow guiding element.

But a double structure of a flow guiding element and an external protection structure, which is otherwise constructed, is also conceivable. Thus, different geometries can be combined in relation to the respective inner or outer diameter or cross section. A ramp-shaped structure or also a structure ensuring a targeted and reversible wedging of the flow guiding element with the external protection structure is also conceivable. A snap-lock or clip mechanism to each other is also contemplated.

It is also possible to form a thread-like structure on the outside of the flow guiding element and/or on the inside of the outer protective structure, which can engage into one another or in principle act on one another. There may be friction-increasing, adhesive or grooved structures on the outside of the outer protective structure, whereby the user can safely handle the outer protective structure without slipping.

The rotatability of the flow guiding element with respect to the outer protective structure about the longitudinal axis can likewise be achieved without significant longitudinal movement: on the outside of the flow guiding element, a straight groove-shaped recess is formed, relative to the transverse axis, into which recess the projection on the inside of the outer protective structure engages. Alternatively, the straight groove-shaped recess can also be formed on the inner side of the outer protective structure, and the projection just described can also be formed on the outer side of the flow-guiding element.

At least one path limiting element may be disposed on either the flow directing element or the external protective structure or both. The path-limiting elements can engage into one another or also act on one another in another manner. The path limiting element can influence, in particular reduce, the displacement of the flow guiding element or the external protective structure alone or relative to one another in the longitudinal direction until a certain point can be achieved or made impossible. The path limiting element can likewise be designed such that it influences, in particular reduces, the rotational movement about the longitudinal axis until a certain point can be reached or is made impossible.

There may be a spring between the flow guiding element and the outer protective structure. In the longer (less compact) state, the spring may ensure that the outer protection structure protrudes in the longitudinal direction towards the user with the flow guiding element. If the spring is now compressed by active action, the outer protective structure is also moved towards the vein so that the end of the flow guiding element remote from the vein is no longer protruding. Whereby another suitable element can be connected to the flow guiding element. If the element is now removed, protection of the end of the flow guiding element remote from the vein is again produced, since the flow guiding element is again extended in the longitudinal direction by the external protection structure. The spring may also be between the external protective structure and the end of the lumen of the venous retention sleeve remote from the vein.

It is also conceivable that the site of the additional element, for example the extraction element, the infusion line, the three-way tap or the tap magazine, which is in contact with the end remote from the vein is constructed similarly or identically to that just described. In order to be able to achieve such a connection to the end of the flow guiding element of the venous indwelling cannula, which end is remote from the vein, which end is designed as such, together with the outer protective structure, the outer protective structure of the extraction element can have a larger diameter than the outer protective structure of the flow guiding element of the venous indwelling cannula. Thus, when the venous indwelling cannula and the extracting element are connected, the external protection structure of the extracting element can be pushed onto the external protection structure of the venous indwelling cannula. It is also conceivable that the outer protective structure of the extraction element has a smaller diameter than the outer protective structure of the flow guiding element of the venous indwelling cannula. In this case, the outer protective structure of the extraction element may be pushed under the outer protective structure of the venous indwelling cannula when the venous indwelling cannula and the extraction element are connected. In an advantageous embodiment, the outer protective structure of the extraction element can be pushed into a cavity formed between the outside of the flow guiding element and the inside of the outer protective structure of the venous retention sleeve at the venous retention sleeve.

The connection points of the infusion line or of other hose systems, for example of the respiratory hose system, can also be formed in the manner described, independently of the venous indwelling cannula, from or to the medical filter system, for example the pathogen filter system. The known luer lock element can also be advantageously modified in the manner described. Can be used generally independently of the iv cannula.

A semicircular or recess-shaped structure which opens upwards and protects the connection of the chamber away from the vein from contamination by skin pathogens can likewise be arranged at the end of the chamber 7 and/or the connection element 9 away from the vein. The structure may be configured such that it is kneadable or deformable and may be shaped not only by the user or patient, but also to accommodate individualized anatomical features. The structure may also have thermoplastic or antimicrobial properties and be provided with a friction-increasing or adhesive surface in order to reduce the risk of the venous indwelling cannula slipping out of the patient.

Spring blocking mechanism as puncture protection

The venous indwelling cannula may advantageously be improved with a spring blocking mechanism for blocking the needle in the venous catheter.

The spring blocking mechanism can be configured such that a spring-shaped or spiral-shaped structure (hereinafter referred to as "spring") ensures in the initial/rest state that the entire puncture needle is surrounded by the venous catheter, in particular also the end of the puncture needle close to the vein and the puncture needle tip. Thus protecting the patient and user from needle stick injuries. The spring is in its relaxed, deactivated rest or initial state, and is formed longer in this case than in the activated state in the case of a compressed spring or shorter in this case in the case of an extended spring. The spring force is overcome by the user in the transition to the activated state, i.e. if the puncture needle should be pushed out of the venous catheter at the end close to the vein.

The spring can be designed such that it encloses the lancet over part, most or all of its length, i.e. the lancet is guided at least partially longitudinally displaceably and/or rotatably through the spring.

In one advantageous embodiment, the outer diameter of the puncture needle can differ, for example be smaller, from the other outer diameters of the puncture needle over at least a part of the length of the spring which encloses the puncture needle in its region.

The longitudinal mobility of the spring can be reduced or eliminated by at least one path limiting element which can be located on the needle. The path limiting element may be configured such that the puncture needle has an alternating diameter, for example also in the form of a projection, edge, projection, wing or arch which secures the spring surrounding the puncture needle in a specific position. This may be made at one or both ends of the spring or between existing helical spring coils. It is also possible that the diameter of the puncture needle increases in a ramp-like or stepped manner.

The spring prevents spontaneous movement of the puncture needle in the longitudinal direction relative to the intravenous catheter by means of the longitudinal mobility of the spring relative to the puncture needle being reduced or eliminated by means of the at least one path limiting element as described hereinabove. The springs must be activated by external influences, for example compressed/pressed together, in particular in order to achieve a longitudinal movement of the puncture needle towards the vein, which is required, whereby the puncture needle tip protrudes the intravenous catheter in the longitudinal direction towards the vein. Only then can puncturing be performed.

The spring may also be integrated directly into the needle or connected to the needle. The spring may illustratively be coupled to the needle such that the spring is coupled to the needle distally from the vein. The spring may also protrude from the needle away from the vein, i.e. be connected inseparably to the needle. In a further advantageous development, the spring can be in a hollow extension element which is a continuation of the venous catheter towards the user and to which, for example, an extraction element or an infusion hose can be connected. In a further advantageous embodiment, the spring can enclose the puncture needle in a region where the puncture needle is connected to and/or transitions into other components of the venous indwelling cannula remotely from the vein.

The helical spring coils of the spring may be spaced less apart from each other at both ends than between the ends in the direction of the longitudinal axis of the spring. Alternating spacing over the entire length of the spring is possible.

Likewise, the puncture needle may be coupled to, connected to, or surrounded by an element in contact with the spring. For example, the element may be formed in the form of a disk-like structure having a central opening in which the puncture needle is guided movably and/or rotatably. However, it is also conceivable that the element is firmly connected to the puncture needle, so that no longitudinal displaceability of the element relative to the puncture needle is obtained.

If the lancing process is now started, the user can activate the spring blocking mechanism so that the lancet moves along its longitudinal axis toward the vein. The end of the puncture needle, in particular the puncture needle tip, which is adjacent to the vein now protrudes the venous catheter in the longitudinal direction towards the vein. Thus, venipuncture may be achieved.

Therefore, a force must always be exerted by the user from the outside in the longitudinal direction on the spring, whereby the spring is activated and the tip of the puncture needle is pushed in the longitudinal direction beyond the venous catheter towards the vein. If no force is now acting from the outside, the puncture needle is automatically pulled back into the intravenous catheter by the spring, thereby deactivating and providing puncture protection, since the entire puncture needle is enclosed by the intravenous catheter. If the force is only acting temporarily, the puncture protection is only eliminated during said time.

The spring blocking mechanism can also be activated, for example, via a control element, for example a button or a support (hereinafter referred to as a "button"), which can be pressed down and trigger a movement of the puncture needle, for example in the manner of a ballpoint pen mechanism.

In an advantageous development, the puncture needle can be moved in the longitudinal direction towards the vein when the button is first pressed, and then remain in said position first, for example by latching with or otherwise interacting with the path-limiting element. The button may also remain in a depressed position, for example by snapping or otherwise interacting with the path-defining element. The at least one path-limiting element can thus ensure that the puncture needle and/or the button, respectively, remain in the desired position.

On the second press of the button, the puncture needle and the button again reach their respective starting positions, i.e. the puncture needle is now moved away from the vein. Here, a state in which the puncture needle and the button are moved toward the vein even more than previously in the longitudinal direction can be temporarily reached.

The push button may be connected directly to a puncture needle, which for example continues at the end of the venous indwelling cannula remote from the vein or which for example also surrounds the puncture needle. It is also conceivable that the push button is connected to the puncture needle only indirectly via another component, for example another spring.

If a vein is reached at the time of puncture, which is shown by the back flow of blood into the components of the venous indwelling cannula, the spring blocking mechanism that was initially activated for the puncture is deactivated again by the user, the puncture needle being moved away from the vein in the longitudinal direction. The intravenous catheter can now be advanced into the vein without the tip of the needle extending beyond the intravenous catheter in the longitudinal direction toward the vein. However, because the puncture needle is still in the intravenous catheter, the puncture needle can hold the intravenous catheter for advancement into the vein and thereby stabilize the intravenous catheter.

The spring blocking mechanism can in principle be activated or deactivated by a pressure or a pulling force at a connecting element or a holding element located remotely from the vein at the venous indwelling cannula. In particular, not only activation, but also deactivation by pressure is possible. In particular, it can be advantageous if the spring can remain in the active state without a force acting continuously on the outside being required for this purpose. A mechanism that ensures that the spring latch is in the activated state may be used.

In an advantageous embodiment, the connecting element on the upper side of the venous indwelling cannula can also be connected to the puncture needle via a spring, for example, to which the extraction element can be connected. The connecting element can be connected to the spring directly or via another element. It is then possible that the user can change the position of the puncture needle in the longitudinal direction, for example with one finger of the hand with which the puncture is performed. The retaining element may have a complementary shape or negative contour of a human thumb or a human fingertip. The surface may be composed of or coated with at least one friction-increasing material.

It is conceivable here that, due to special properties, for example, to the different numbers and/or spacings of the windings and/or the elastic properties of the springs, the tip of the puncture needle, i.e. the section of the puncture needle that protrudes in the longitudinal direction beyond the venous line, can be set before the puncture process. The characteristics just mentioned also allow the maximum mobility of the puncture needle in the longitudinal direction, in particular also the maximum advance into the vein.

By means of the characteristics just mentioned, it is also possible to preset that a maximum pressure is applied to the puncture needle or the venous catheter, so that in particular also when the venous catheter is advanced into the vein, no undesired wounds and possible second perforations of the vein wall occur anymore.

Traffic light systems having the colors "green", "yellow" and "red" are conceivable here. It is also conceivable that in the red region, the advancement of the component to be advanced towards the vein is automatically interrupted or not possible.

In an advantageous development, the puncture protection can also be designed such that a rollable structure or a rollable element (hereinafter referred to as "rollable element") is present at the inner side of the venous catheter or at the inner side of the component connected to the venous catheter in the longitudinal direction towards the vein.

For example, the evertable element may be in the form of a hose of tapering or widening diameter, in the form of a horn or also in the form of a cap with a cap peak. If the tip of the puncture needle, which is close to the vein, is now moving away from the vein, the element folds over as the tip passes and protectively and permanently encloses the vein.

The inner side of the evertable element may advantageously be composed of or coated with a friction increasing material. The evertable element may be constructed of at least one puncture resistant material. The evertable element may also have a spiral, wave and/or braid-like structure.

The puncture-resistant material may be a metal, also in the form of a metal alloy, or a correspondingly puncture-resistant plastic material or a natural material. For example carbon fiber reinforced laminates, polymers and/or teflon are considered as plastic materials, but also in combination with each other. Aramid fibers may also be advantageously used. The evertable element may also be composed of nitinol. All materials mentioned herein may be used alone or in any combination with each other.

It is also contemplated that the elements just described do not roll over, but are rather sleeved/pushed onto the needle tip upon relative movement of the needle with respect to the intravenous catheter. If the element is formed in at least two layers, at least one layer of the element can also be slipped/pushed onto the piercing tip by a rolling-off movement.

Multilayer puncture needle as puncture protection

The puncture protection can also be designed such that the puncture needle has or consists of two hollow bodies which are mounted longitudinally displaceably relative to one another. For example, the hollow body may be composed of a metal or metal alloy, but may also be composed of any other puncture resistant material as described hereinabove.

The outer hollow body can be formed cylindrically and at both ends can be formed cylindrically. The inner hollow body guided in the outer hollow body can likewise be configured cylindrically, but with a smaller outer diameter than the outer hollow body.

The hollow body inside may be provided with pointed structures at its end close to the vein and/or with edging suitable for puncturing, thus constituting the puncture needle tip.

The spring blocking mechanism with compression or tension springs previously described with respect to the interaction between the puncture needle and the intravenous catheter may alternatively or additionally also exist with respect to the interaction between the inner hollow body and the outer hollow body of the puncture needle. The spring blocking mechanism then serves to block the inner hollow body of the puncture needle in the outer hollow body. The spring blocking means can be configured such that in the initial/rest state, a spring-shaped or spiral-shaped structure (hereinafter referred to as a "spring") is ensured by means of the spring force that the pointed structure of the inner hollow body, which is close to the vein, takes up a position in which the outer hollow body protrudes out of the inner hollow body together with the pointed structure or is at least accommodated therein, and in particular ensures that said position does not change in the absence of external pressure. For example, at the end remote from the vein, the internal hollow body may be provided with or surrounded by a spring. At the end of the hollow body facing away from the vein, a holding element or a connector for an extraction element can be formed.

If the inner hollow body is now manually actively pressed towards the vein, its tip near the vein protrudes beyond the outer hollow body towards the vein and can be used for venipuncture. The spring remote from the vein is actively tensioned (compressed/shortened) here. If the manual pressure is now removed, the spring ensures that the inner hollow body moves away from the vein again, i.e. the tip of the inner hollow body is again surrounded by the outer hollow body. In this way, puncture protection is provided all the way out of the direct puncture process.

The inner hollow body and the outer hollow body can be supported in the venous catheter not only in a longitudinally movable manner but also in a rotatable manner about a longitudinal axis, respectively, also in a rotatable manner relative to each other. The movement, and also the movement relative to each other, can be reduced or eliminated by at least one path limiting element.

There may be at least one material or substance between the inner hollow body and the outer hollow body that reduces the frictional resistance between the two body parts. This may be, for example, a sterile fat or oily substance or also nanoparticles. The same can be true for the space between the external hollow body and the intravenous catheter. The terminating element may ensure that the substance cannot leave the respective space, i.e. the space is sealed fluid-tightly towards all sides. The space between the inner hollow body and the outer hollow body or between the outer hollow body and the venous catheter can also be designed as a ball bearing or other rolling bearing.

Non-linear embodiment of a puncture needle and/or an intravenous catheter

Due to the special nature of the intravenous catheter, the risk of damage to the intravenous catheter is also minimized by the non-straight puncture needle. In addition to the puncture needle, the venous line can thus also be formed in a curved, bent or spiral-spring-shaped/helical manner in the starting position before, during or after application to the patient.

It is also possible that the puncture needle and/or the intravenous catheter comprise straight sections between curved, bent or spiral spring-shaped/helical sections. It is also possible to combine curved, bent or spiral spring-shaped/helical sections with one another at will. In an advantageous development, the venous catheter is composed of at least one material which ensures that the venous catheter also retains its original shape over part of its length, over a large part of its length or over its entire length without an inserted puncture needle.

Similarly to when screwing in the screw, in a suitable embodiment for this purpose, the part of the puncture system to be introduced into the patient can be introduced into the patient by means of a rotational movement. The axis of rotation here extends perpendicularly to the skin surface.

In conventional blood glucose meters with sensors under the skin, a straight needle under the skin is used. However, the sensor can then easily slide out of the skin. Furthermore, if the straight needle drills too deep into other anatomical structures due to too strong external pressure, damage can be determined. For example, a spiral needle can easily eliminate the problem.

The entire venous indwelling cannula can likewise be constructed in a curved, bent or spiral-spring-shaped/helical fashion. However, it is also possible, in particular, for the venous indwelling catheter to be constructed straight away from the vein.

At the end of the venous indwelling cannula near the vein, the puncture needle and/or venous catheter, constructed as described above, may contain a sensor that measures a parameter in the blood or under the skin, for example a parameter in subcutaneous adipose tissue. Glucose values may be measured exemplarily. For example, the partial pressure of oxygen can also be measured. The sensor may be configured such that it can enable data to be transmitted to a receiving device outside the patient, such as a smart phone or another electronic device. The sensor may not only be part of the needle and/or the intravenous catheter, but may also be on an inner or outer surface of the needle and/or the intravenous catheter. For example, the sensor may be constructed in a spiral or film-like manner, and other designs are possible. The configuration just described may also be designed for prolonged or permanent implantation, for example directly under the skin. The configuration just described may also be used as an example of a measuring device for measuring a glucose value in a diabetic patient. The puncture needle and/or the venous line can be hollow, partially solid or completely solid in this case, and can additionally be connected to a pump, for example an insulin pump, also via other connecting elements, for example a hose. The configuration just described no longer has to comprise an intravenous catheter, the puncture needle can have a reduced size with respect to length and/or outer diameter and rather be constructed in the sense of a conventional hypodermic needle.

Bending of a puncture needle and/or an intravenous catheter in the region of a skin access site

The puncture needle and/or the venous catheter may in particular be bent and/or folded in the region of the transition to the other component of the venous retention sleeve away from the vein. The bending or kinking site corresponds to an area of skin level in the case of an intravenous catheter in a patient. Where the intravenous catheter may be subjected to special mechanical loads depending on the use. In contrast to venous catheters which extend straight from the venous indwelling cannula towards the vein, the venous catheter may extend at least 1 ° from its straight line, but is preferably measured at an angle of 2 ° to 5 °, 6 ° to 10 °, 11 ° to 25 °, 26 ° to 45 ° or more than 45 °. Thus, the intravenous catheter constitutes a kink that can be directed upwards or downwards. The venous line can also be modified in the region mentioned by means of at least one spiral/wave-shaped or mesh-shaped, braid-shaped or grid-shaped structure and by means of a sealing coating, for example a PTFE coating. Combinations with transversely extending, longitudinally extending or diagonally extending structures are conceivable, which can also ensure the desired stability of the wall of the venous catheter in the region alone. However, the venous line can also be formed as a conventional venous line in the region mentioned and additionally contain the elements just mentioned. In particular, the element may also be embedded in the wall of a conventional intravenous catheter.

The puncture needle guided in the intravenous catheter can be modified in the same way.

Settable rigidity of the outer envelope

According to an advantageous embodiment of the invention, the outer jacket has two hollow bodies which are mounted so as to be longitudinally movable relative to one another. For example, the two hollow bodies can be formed as an inner intermediate tube and an outer intermediate tube, the inner intermediate tube being arranged at least partially in the outer intermediate tube and the inner intermediate tube being movable in the outer intermediate tube. For example, a displacement mechanism can be provided, by means of which it is possible to set how much the inner intermediate tube is displaced relative to the outer intermediate tube. In particular, the amount of overlap between the inner intermediate tube and the outer intermediate tube can thereby be set, for example by manual adjustment. If the amount of overlap is set to a low value, the rigidity decreases, so that the outer envelope becomes more elastic. If the amount of overlap is set to a high value, the rigidity increases, so that the outer envelope becomes less elastic. This function may be advantageously used, for example, when administering an iv cannula to a patient. During the administration process, i.e. when advancing into the vein, it is advantageous to set the rigidity of the outer envelope to a higher amount, i.e. the outer envelope is more rigid. In the introduced state of the venous indwelling cannula, i.e. when indwelling in a patient, a lower rigidity is again advantageous, since the venous catheter can then be better adapted to possible movements of the blood vessel and the patient.

Side hole

According to an advantageous embodiment of the invention, it is provided that the outer jacket has lateral through openings (side openings) through which the liquid can flow from the inside of the outer jacket to the outside and vice versa. Hereby, a better administration, in particular a better distribution of the drug, can be achieved in certain situations. It is also possible that some or all of the through openings are initially closed, i.e. in the delivery state of the venous indwelling cannula, and are only opened in the state of administration to the patient. For example, some or all of the through openings may initially be closed by a bioresorbable material. Then, if the bioresorbable material dissolves, the through openings are released.

figure 51 shows in longitudinal section a schematic view of the venous indwelling cannula in the first embodiment,

figure 52 shows in cross-section a schematic view of an iv set cannula in a second embodiment,

figure 53 shows in longitudinal section a schematic view of the venous indwelling cannula according to figure 52,

figure 54 shows in cross-section a schematic view of an iv set cannula in a third embodiment,

Figures 55, 56 show in longitudinal section a schematic view of a part of the wall of the venous indwelling cannula according to figure 54,

figures 57-59 show an iv set cannula in a fourth embodiment,

figures 60-62 illustrate an iv set cannula in a fifth embodiment,

figures 63-65 illustrate an iv set cannula in a sixth embodiment,

figures 66 and 67 show an iv set cannula in a seventh embodiment,

figures 68-70 show an iv set cannula in an eighth embodiment,

figures 71-74 show an iv cannula in a ninth embodiment,

figures 75-79 illustrate an iv set cannula in a tenth embodiment,

figures 80-85 illustrate an iv set cannula in an eleventh embodiment,

figures 86 and 87 show an iv cannula in a twelfth embodiment,

figures 88 and 89 show an iv cannula in a thirteenth embodiment,

fig. 90 to 92 show an iv cannula in a fourteenth embodiment.

Fig. 51 shows a schematic view of the venous indwelling cannula 301 in longitudinal section. The venous indwelling cannula 301 has a venous catheter 302 in which a puncture needle 303 can be guided longitudinally movably in the venous catheter 302.

The venous indwelling cannula 301 is here configured as a peripheral venous indwelling cannula 301. It is clear that the intravenous catheter 302 is formed of a puncture resistant material like a tightly wound coil spring, such that a wave-shaped surface is created. The venous line 302 is made of a puncture-proof material over its entire length. The flexibility of the venous catheter 302 is ensured by the helical configuration. This construction of the venous catheter 302 provides a puncture and cut protection that protects the venous catheter 302 from, for example, being pierced by the tip 306 of the puncture needle 303 near the patient when the venous indwelling cannula 301 is administered. Thus, the risk of damaging the intravenous catheter 302 is minimized. By repeated movements of the puncture needle 303 relative to the intravenous catheter 302, the intravenous catheter can no longer be sheared by the tip 306 of the puncture needle 303 close to the patient. Thereby, waste products caused by damaged intravenous catheters can be significantly reduced. Furthermore, repeated application of the venous indwelling cannula 301 within the scope of the puncturing procedure is feasible under permanent sterile precautions at the organism. This is especially important if an erroneous puncture is initially made, i.e. the vessel or venous catheter 302 is inadvertently missed on the first puncture and cannot initially be advanced far enough into the vessel.

For improved extraction, the venous catheter 302 is provided with a sealing coating 304. A minimal opening, through which the extraction is difficult, can be produced by the wave-shaped surface, since, for example, air can be undesirably extracted through said opening. The hermetic coating 304 may minimize or prevent undesired extraction of air. The sealing coating 304 is advantageously a PTFE coating, which at the same time simplifies the introduction of the venous catheter 302 into the penetrated body part. By means of the additional expansion element 3010 at the end of the venous catheter 302 close to the patient, a uniform widening is achieved when advancing the venous catheter 302 in the penetrated body part.

Administration of the venous indwelling cannula 301 at the living being may be performed, for example, as follows:

1. the vein is punctured by means of the puncture needle 303,

2. a spiral-shaped intravenous catheter 302 with a sealing coating 304 is advanced through the tip 306 of the needle 303 near the patient into the vein to a desired location,

3. the lancet 303 is removed/pushed back,

4. the spiral-shaped intravenous catheter 302 is closed at the end remote from the patient.

The venous indwelling cannula 301 has two retaining elements 305. The holding element 305 may realize: the user operates the venous indwelling cannula 301 with one hand, wherein the second hand may for example be used to stabilize the body part to be penetrated. The puncture needle 303 is configured as a hollow needle. After the puncture is completed through the tip 306 of the puncture needle 303 near the patient, the user can directly recognize whether the vein is correctly punctured by: the hollow lancet 303 is filled with venous blood and enters the chamber 307, whereby the user can directly perceive the blood.

After the puncture is completed, the intravenous catheter 302 may be pushed into the punctured body part and the puncture needle 303 together with the cavity 307 may be pulled out of the part of the iv cannula 301 remaining in the body part immediately. The safety mechanism may be configured to shield the patient-proximal tip 306 of the needle 303 after being pulled from the iv cannula 301, thereby protecting the user as well as the living being from possible puncture injuries.

The venous catheter 302 may be fixedly held at the living being in its final position in the body part being penetrated via the fastening element 308. The fastening can be performed by a self-adhesive wound dressing, which secures the venous retention sleeve 301 to the living being via the fastening element 308. The described fastening element 308, which may be configured as a wing, for example, is an optional element of the venous indwelling cannula 1.

The puncture needle can here extend substantially in the middle between the holding element 305 and/or the fastening element 308.

It is clear that the functions of the holding element 305 and the fastening element 308 can be combined in one element. This may enable a simple manufacture of the venous indwelling cannula 301, wherein the configuration of the venous indwelling cannula 301 remains simple for the user at the same time.

The extraction element, e.g. a syringe, may be connected via a connection element 309. The connecting element 309 can be embodied here as a valve, which allows simple administration or drawing of blood. In this case, in the non-touching state, the valve prevents liquid, for example blood, from flowing out of the connecting element 309 in a retrograde manner. In the non-touching state, the valve also prevents air from entering the connecting element 309 from the outside. Furthermore, the connection element 309 may contain a filter that prevents coarse particles, germs and air from entering into the interior of the connection element 309 and thus into the interior of the venous indwelling cannula.

An extraction element, such as a syringe, may be connected to the chamber 307. Thus, the venous indwelling cannula can be introduced into the vein with continued withdrawal by means of the syringe. Thus, the success of the puncture can be determined directly and very accurately. The chamber 7 can also be formed here as a further valve which allows a flow of fluid in only one defined direction. Furthermore, the chamber 307 may alternatively or additionally be formed as follows: the chamber prevents air from entering or allows air and other gases and vapors to pass in only one defined direction. For example, the chamber 307 may be constructed in the same manner as the connecting element 309.

The chamber 307 and the connecting element 309 may be covered by a protective cover, so that no undesired contamination occurs when the chamber 307 and the connecting element 309 are not used. The protective cover can be connected to the chamber 307 and/or the connecting element 309 via connecting plates.

It is also contemplated that the shield may be connected to the connecting element 309 or the chamber 307 via a connecting plate when the shield is pressed downward, the fluid flow in the venous indwelling cannula being interrupted or slowed.

The intravenous catheter 302 has circumferentially distributed recesses 3011 at the end near the patient. By means of the recess 3011, for example, a uniform output of the medicament into the living being can be achieved. Thus avoiding an undesired local high concentration of drug output into the living being. In addition, by providing a plurality of recesses 3011, the penetration rate of the administered infusion solution and drug can be increased. Furthermore, the extraction of fluids, for example blood, from the living being via the resident venous catheter or via the resident venous indwelling cannula can thereby be simplified. Thus, if the venous indwelling cannula is applied, for example, for drainage of fluids, vapors and/or gases, for example, within the scope of a puncture of the pleural cavity, other cavity or in-vivo space described hereinabove, a desired retrograde spontaneous outflow of fluids, vapors and/or gases from the venous indwelling cannula may also be possible with a corresponding configuration of the other components of the venous indwelling cannula.

As shown in fig. 52 and 53, the intravenous catheter 302 has a wall 3043. The wall has an inner side 3041 and an outer side 3040. The intravenous catheter 302 or wall 3043 may have a circular or oval profile at the outside 3040 or, as shown in fig. 52, a polygonal profile, such as a hexagonal profile. Additionally, a flow channel in the form of a recess 3042 may be shaped or embedded into the outer side 3040 of the wall 3043. The recess 3042 may be configured as an elongated groove, for example, and extends along the venous catheter 302 over a more or less long longitudinal extent L1, L2, L3.

Fig. 54 shows an embodiment of the intravenous catheter 302 in which the flow channel extending in the longitudinal direction is in the form of a hollow channel 3044 extending within a wall 3043. Here, as shown in fig. 55 and 56, the hollow passages 3044 may have inlet openings 3045 for inflow of fluid at the outer sides 3040, respectively. The exit openings 3046 at which fluid flowing through the hollow channels 3044 may again flow from the respective hollow channels 3044 may also optionally be at the outer side 3040, as shown in fig. 55, or at the inner side 3041 of the wall 3043, i.e., toward the inner tube lumen of the intravenous catheter 302.

The flow channel does not have to run exactly in the longitudinal direction of the venous catheter 302 or parallel to the longitudinal direction, but can also run completely or in sections obliquely to the longitudinal direction, for example in a spiral shape.

Fig. 57 to 59 show another embodiment of a venous indwelling cannula 301, in which a venous catheter 302 has a flow channel extending in the longitudinal direction in the form of a recess 3042 at the outer side 3040 of a wall 3043. Fig. 57 shows the complete venous indwelling cannula 301 in a perspective view. The area a marked in fig. 57 is shown partially enlarged in fig. 58. Fig. 59 shows a cross-sectional view through the venous indwelling cannula 301 in the region of the recess 3042. As can be seen, the venous catheter 302 has a circular profile at the outside. The recess 3042 extends over a length L in the longitudinal direction of the venous catheter 302.

Fig. 60 to 62 show another embodiment of an iv catheter 301 in which an iv catheter 302 has a flow channel extending in the longitudinal direction in the form of a hollow channel 3044 extending within a wall 3043. Fig. 60 shows the complete venous indwelling cannula 301 in a perspective view, fig. 61 shows the region B marked in fig. 60 in an enlarged view, and fig. 62 shows a cross-sectional view through the venous catheter 301 in the region of the hollow channel 3044. It can be seen that the hollow channel 3044 need not necessarily have a circular cross-sectional shape, but may have, for example, a flattened cross-sectional shape, such as an oval profile or a curved profile following the arcuate shape of the wall 3043.

Fig. 63 to 65 show an embodiment of an iv catheter 301, in which the iv catheter 302 has a polygonal outer contour 3025 on the outside over a specific limited longitudinal section. Fig. 63 shows the complete venous indwelling cannula in a perspective view, fig. 64 shows the region C marked in fig. 63 in an enlarged partial view, and fig. 65 shows a cross-sectional view through the region of the polygonal outer contour 3025. It can be seen that the venous catheter 302 has a polygonal outer contour 3025 over a longitudinal section limited in length L, and is furthermore formed as a conventional venous catheter, for example with a circular outer contour. For example, a polygonal region 3025 may be provided at the end of the intravenous catheter 302 near the patient. The outer contour of a hexagon is shown by way of example, but other polygonal designs are also possible.

Fig. 66 and 67 illustrate one embodiment of an iv cannula 301 in which the needle 303 is blunt-formed at the tip 306 and at least a portion of the needle 303 is formed of a bioresorbable material 3026. Fig. 66 shows the complete venous indwelling cannula 301 in a perspective view, and fig. 67 shows the region D marked in fig. 66 in an enlarged partial view. As can be seen, the puncture needle 303 is formed with a region of bioresorbable material 3026 in a section near the hollow body, which region resorbs itself after a certain time upon contact with the patient. In addition, the puncture needle 303 is formed relatively blunt at its tip 306. For example, the needle 303 may be constructed of a bioresorbable material 3026 over a region of length L. It is also possible that parts of the intravenous catheter 302, in particular in the region close to the hollow body, are also composed of a bioresorbable material.

Fig. 68-70 illustrate one embodiment of an iv cannula 301 having a spring blocking mechanism 3020 for blocking the needle 303 in the outer sheath (i.e., iv catheter 302). The spring blocking mechanism 3020 serves as a puncture protection in the initial state or rest state of the iv catheter 301. In this state, the puncture needle 303 with its tip 306 is pulled back completely into the venous catheter 302.

Fig. 68 shows the venous indwelling cannula 301 in a perspective view, and fig. 69 and 70 show the venous indwelling cannula 301 in a top view. The spring blocking mechanism is in an initial state in fig. 68 and 69 and in an activated state in fig. 70.

The spring blocking mechanism 3020 may have a compression spring 3021 that generates pressure between a component connected to the puncture needle 303, for example the chamber 307, and a component connected to the intravenous catheter 302, such as, for example, the base body 3080, at which the holding element 308 is fastened, or at least in a specific operating state. The spring blocking mechanism 3020 also has a first locking element 3022 coupled to the member to which the needle 303 is connected and a second locking element 3023 coupled to the base body 3080. If the venous indwelling cannula 301 is now transferred into the activated state, i.e. the venous indwelling cannula 301 is transferred into the activated state by pushing the puncture needle 303 out of the venous catheter 302, as shown in fig. 57, this can be done by applying pressure at the holding element 305, the compression spring 3021 is compressed. Starting from a particular attitude, the first locking element 3022 is locked at the second locking element 3023. Thereby occupying and maintaining the activated state of the venous indwelling cannula 301.

To disengage the lock, it may simply be manually pressed onto the first locking element 3022, i.e., pressed together toward the base body 3080. The lock can thereby be disengaged, for example in the form of: the second locking element 3023 has a T-shaped profile. Then, by pressing the first locking elements 3022 together, they can be slid past the second locking elements 3023 in a manner supported by the compression springs 3021. After the lock between the first and second locking elements 3022 and 3023 is released, the needle 303 is automatically pulled back into the intravenous catheter 302 again by the force of the compression spring 3021.

Fig. 71-74 illustrate one embodiment of an iv cannula 301 in which there is a material 3047 with increased sliding capability on at least one longitudinal section on the outside of the needle 303 and/or the inside of the outer sheath 302. Fig. 71 shows the venous indwelling cannula 301 in a perspective view, fig. 72 shows the venous indwelling cannula in a longitudinal section, fig. 73 shows the region E marked in fig. 72 in an enlarged partial view, and fig. 74 shows a cross section through the venous indwelling cannula 301. By the effective material 3047 between the outer side of the lancet and the inner side of the outer envelope 302, an increased sliding capacity is achieved between the lancet 303 and the outer envelope 302, in particular in the longitudinal movement direction of the lancet 303. The material 3047 may be present in the form of friction-reducing additives or in the form of individual rolling bodies, similar to those in rolling bearings.

Fig. 75, 76, 77, 78, 79 illustrate one embodiment of venous indwelling cannula 301 in which the outer sheath has two hollow bodies, an inner middle tube 3027 and an outer middle tube 3028. Fig. 75 shows the venous indwelling cannula in a perspective view, fig. 76 shows the venous indwelling cannula in a side view, fig. 77 shows the venous indwelling cannula in a longitudinal section, fig. 78 shows the venous indwelling cannula in a side view, and fig. 79 shows the venous indwelling cannula in a longitudinal section. Venous indwelling cannula 301 is in a retracted state in fig. 75-77 and in an extended state in fig. 78 and 79.

The inner intermediate pipe 3027 is guided in the outer intermediate pipe 3028 and is supported in a longitudinally displaceable manner therein. The outer intermediate tube 3028 is securely attached to the base 3080. The inner intermediate tube 3027 is firmly connected to the displacement mechanism 3029. The moving mechanism 3029 has a manual operation element 3030. The manual actuating element 3030 can be moved back and forth in specific regions of the base body 3080. For example, the respective posture may be fixed by a locking device. For example, if the manual operation element 3030 moves from the posture shown in fig. 77 to the posture shown in fig. 79, the inner intermediate tube 3027 moves together so as to push the outer intermediate tube 3028 farther. As shown for example in the retracted state in fig. 77, the overlap between the inner and outer intermediate tubes 3027, 3028 is relatively small, whereas in the extended state in fig. 79 the overlap is significantly greater. Thus, in the retracted state, the outer sheath 302 is less rigid than in the extended state, because in the extended state the outer intermediate tube 3028 is additionally reinforced by the inner intermediate tube 3027 therein. Thus, the strength of the outer jacket 302 may be set at a particular level or also steplessly.

Fig. 80-85 illustrate one embodiment of an iv catheter 301 in which the outer sheath has two hollow bodies, an inner middle tube 3027 and an outer middle tube 3028. Fig. 80 and 81 show perspective views, fig. 82 and 84 show side views, and fig. 83 and 85 show longitudinal sections. The iv cannula is in a retracted state in fig. 80, 82 and 83 and in an extended state in fig. 81, 84 and 85.

Unlike the embodiment of fig. 75 to 79, in this embodiment the inner intermediate pipe 3027 is designed significantly longer, in particular longer than the outer intermediate pipe 3028. In the retracted state, the inner intermediate tube 3027 is completely or at least mostly within the outer intermediate tube 3028. In the extended state, the inner intermediate tube 3027 extends from the outer intermediate tube 3028 at a particular measurement. For example, an intravenous cannula may be administered to a patient in a retracted state. In the subsequent operation of the venous indwelling cannula at the patient, then the transition is made into the extended state. Then, via the portion of the inner intermediate tube 3027 that protrudes from the outer intermediate tube 3028, for example, a medication may be administered or blood may be drawn. The inner intermediate tube 3027 may have the lateral through openings (side openings) mentioned here, at least in the region which can protrude from the outer intermediate tube 3028.

Fig. 86 and 87 show an embodiment of the venous indwelling cannula 301 in which a spiral or wave-shaped structure 3048, e.g. a helically encircling, mostly longitudinally extending flow channel in the form of a groove, is formed at the inner side of the venous catheter 2. In general, the wall 3043 of the venous catheter 302 may have a plurality of helical or wave-shaped structures 3048, such as the structures 3048 directed toward the medial side 3041 as seen in fig. 87, and alternatively or additionally helical or wave-shaped structures directed toward the lateral side 3040. Thereby, for example, the sliding ability of the puncture needle 303 in the intravenous catheter 302 can be improved. Additional flow channels are also implemented. Here, fig. 86 shows the venous indwelling cannula 301 in a perspective view, and fig. 87 shows the region F marked in fig. 86 in an enlarged partial view. By the spiral design of the structure 3048, a swirling effect of the fluid directed through the outer sheath 302 may be achieved. For example, the infusion liquid may be swirled and output in a better distribution at the patient in the manner described.

Fig. 88 and 89 illustrate an embodiment of an iv catheter 301 in which a spiral or wave-shaped structure 3048, e.g. a spiral-shaped surrounding, mostly longitudinally extending flow channel in the form of a groove, is shaped at the inner side of the iv catheter 302, similar to the previously described embodiment. Here, fig. 88 shows the venous indwelling cannula 301 in a perspective view, and fig. 89 shows the region G marked in fig. 88 in an enlarged partial view. Additionally, the intravenous catheter 302 has a plurality of lateral through openings 3031 in the region proximate to the patient through which liquid can flow.

Fig. 90-92 illustrate one embodiment of an iv cannula 301 in which an iv catheter 302 has a plurality of lateral through openings 3031 in a region proximate to a patient through which fluid may flow, similar to the previously described embodiments. Fig. 90 shows the venous indwelling cannula 301 in a longitudinal sectional view, fig. 91 shows the venous indwelling cannula 301 in a perspective view, and fig. 92 shows the region H marked in fig. 91 in an enlarged partial view. Additionally, the intravenous catheter 302 has a plurality of hollow channels 3044 extending in the longitudinal direction within the wall 3043 in a region proximate to the patient. The hollow channels 3044 can each have an inlet opening 3045, but are formed without the previously described outlet opening 3046, i.e. closed at least on one side. Advantageously, the access opening 3045 is in a region of the intravenous catheter 302 that is not introduced into the patient, i.e., away from a region near the patient. Then, the hollow channel 3044 extends into the region proximate to the patient. For example, the hollow channel 3044 may be filled with air or another medium that may be identified in an imaging examination. If the hollow channel is filled with air, visibility of the end of the intravenous catheter 302 near the patient in an ultrasound examination may be achieved, for example.

The present figures relate only to schematic diagrams depicting a good overview of the components of the venous indwelling cannula according to the present invention. However, the length and size relationship may be different in reality.

The drawings are to be understood as possible embodiments. Other forms according to the teachings of the present invention are also contemplated. Furthermore, the embodiments of the examples are not inseparably connected to one another, so that, for example, the embodiments of the invention are not connected to the specifically described embodiments of the examples. Thus, for example, variability in the number, length or size of the individual elements is contemplated at any time.

List of reference numerals

301. Venous indwelling cannula

302. Intravenous catheter/outer sheath

303. Puncture needle

304. Hermetically sealed coating

305. Holding element

306. The tip of the puncture needle near the patient

307. Chamber chamber

308. Fastening element/holding element

309. Connecting element

3010. Expansion element

3011. Recess(s)

3020. Spring blocking mechanism

3021. Compression spring

3022. First locking element

3023. Second locking element

3025. Polygonal outer contour

3026. Bioresorbable materials

3027. Internal intermediate pipe

3028. External intermediate pipe

3029. Moving mechanism

3030. Manual operating element

3031. Lateral through opening

3040. Outside is provided with

3041. Inside of the inner side

3042. Concave part

3043. Wall with a wall body

3044. Hollow channel

3045. Access opening

3046. Exit opening

3047. Material with increased sliding ability

3048. Spiral or wave-shaped structures

3080. Base body

Claims

1. An indwelling cannula (1, 201) for puncturing a hollow body by means of a puncture needle (30, 2030), wherein the indwelling cannula (1, 201) has at least one catheter (2, 202) with a tubular catheter intermediate tube (22, 2022), in which the puncture needle (30, 2030) is guided longitudinally displaceably, wherein the catheter (2, 202) is set up for, after performing a puncture of a sheath of the hollow body to be punctured, pushing on at least a part of the length of the catheter intermediate tube (22, 2022) and indwelling there for a certain duration through an opening through the sheath of the hollow body to be punctured by means of the puncture needle (30, 2030).

2. The indwelling cannula according to claim 1,

it is characterized in that the method comprises the steps of,

the indwelling cannula (1, 201) has a gripping area which is set up for the user to grip the indwelling cannula (1, 201) in the gripping area during operation.

3. The indwelling cannula according to claim 1 or 2,

it is characterized in that the method comprises the steps of,

the indwelling cannula (1, 201) has a manually operable advancement mechanism (5) by which a relative movement can be generated between the catheter intermediate tube (22, 2022) and the piercing needle (30, 2030) as a result of manual operation, by which a piercing tip (31, 2031) of the piercing needle (30, 2030) protruding from the catheter intermediate tube (22, 2022) at the end near the patient can be accommodated in the catheter intermediate tube (22, 2022).

4. The indwelling cannula according to claim 3,

it is characterized in that the method comprises the steps of,

by means of the advancing mechanism (5), the catheter intermediate tube (22, 2022) can be pushed beyond the piercing tip (31, 2031) of the piercing needle (30, 2030) and/or the piercing tip (31, 2031) of the piercing needle (30, 2030) can be pulled into the catheter intermediate tube (22, 2022).

5. The indwelling cannula according to any one of claim 3 to 4,

it is characterized in that the method comprises the steps of,

one, several or all of the operating elements of the manually operable propulsion mechanism (5) are arranged in and/or form part of the gripping area.

6. The indwelling cannula according to any one of claim 3 to 5,

it is characterized in that the method comprises the steps of,

limiting the relative movement between the catheter intermediate tube (22, 2022) and the piercing needle (30, 2030) that can be produced by manual manipulation of the advancement mechanism (5) to a maximum value.

7. The indwelling cannula according to claim 6,

it is characterized in that the method comprises the steps of,

the maximum value of the relative movement is at least as great as the length of the piercing tip (31, 2031).

8. The indwelling cannula according to claim 6 or 7,

it is characterized in that the method comprises the steps of,

the maximum value of the relative movement is less than twice the length of the piercing tip (31, 2031).

9. The indwelling cannula according to any one of claim 3 to 8,

it is characterized in that the method comprises the steps of,

the propulsion mechanism (5) can be fixed in the following manual operating position by means of a locking device: in the manual operating position, the piercing tip (31, 2031) is accommodated in the catheter intermediate tube (22, 2022).

10. The indwelling cannula according to claim 9,

it is characterized in that the method comprises the steps of,

in the manual operating position of the advancing mechanism (5) in which the piercing tip (31, 2031) is accommodated in the catheter intermediate tube (22, 2022), at least one operating element of the advancing mechanism (5) can be fixed by means of the locking device and/or at least a part of the housing (20) of the catheter (22, 2022) can be fixed at the needle device (3).

11. The indwelling cannula according to any one of claim 3 to 10,

it is characterized in that the method comprises the steps of,

at least one operating element of the propulsion mechanism (5) is designed as a pivotably mounted lever (53) with at least one lever arm.

12. The indwelling cannula according to any one of claim 3 to 11,

it is characterized in that the method comprises the steps of,

the advancing means (5) are designed to produce a relative movement between the catheter intermediate tube (22, 2022) and the piercing needle (30, 2030) by means of a manually applied actuating force and/or by means of a spring force.

13. The indwelling cannula according to any one of claim 3 to 12,

it is characterized in that the method comprises the steps of,

the propulsion mechanism (5) has at least two holding surfaces (50, 54) as actuating elements, against which at least one finger of the user can be placed in each case, wherein the at least two holding surfaces (50, 54) are arranged facing away from one another.

14. The indwelling cannula according to claim 13,

it is characterized in that the method comprises the steps of,

at least one of the gripping surfaces (50, 54) is arranged on a lever arm of a pivotably mounted lever (53) of the propulsion mechanism (5).

15. The indwelling cannula according to claim 14,

it is characterized in that the method comprises the steps of,

The lever (53) is rotatable about a rotation axis (D), wherein the gripping surface (50, 54) provided at the lever arm extends from a position further from the puncture needle (30, 2030) than the rotation axis (D) to a position closer to the puncture needle (30, 2030) than the rotation axis (D), at least in an unactuated state of the propulsion mechanism (5).

16. The indwelling cannula according to any one of claim 3 to 15,

it is characterized in that the method comprises the steps of,

the indwelling cannula (1, 201), in particular the catheter intermediate tube (22, 2022) of the indwelling cannula, has one or more markers by which a relative movement between the catheter intermediate tube (22, 2022) and the piercing needle (30, 2030) due to manual manipulation of the advancing mechanism (5) can be displayed.

17. The indwelling cannula according to any one of claim 3 to 16,

it is characterized in that the method comprises the steps of,

the propulsion mechanism (5) has at least one intermediate position between its final positions, for example in the form of a locking position, which is tactilely detectable by the user.

18. The indwelling cannula according to any of the preceding claims,

it is characterized in that the method comprises the steps of,

the intermediate conduit (22, 2022) has one or more reinforcing elements in one or more regions subjected to increased mechanical loading, respectively, by means of which the bending and/or radial resistance moment of the intermediate conduit (22, 2022) is increased relative to adjacent regions of the intermediate conduit (22, 2022).

19. The indwelling cannula according to any of the preceding claims,

it is characterized in that the method comprises the steps of,

at least the portion of the catheter intermediate tube (22, 2022) which is provided for being placed in the hollow body has at least one helical support structure over its entire length or over a large part of its length, in particular in the form of at least one helically wound, internally hollow guide wire, in which length the puncture needle (3) can be guided longitudinally displaceably.

20. The indwelling cannula according to any of the preceding claims,

it is characterized in that the method comprises the steps of,

the indwelling cannula (1, 201) has, in an intermediate tube exit region (21) in which the catheter intermediate tube (22, 2022) protrudes from a housing (20) of the indwelling cannula (1, 201), a kink protection (42) which completely or at least partially surrounds the catheter intermediate tube (22, 2022) on the circumferential side, by means of which the risk of kinking of the catheter intermediate tube (22, 2022) in the region of the exit point from the housing (20) is reduced.

21. The indwelling cannula according to any of the preceding claims,

it is characterized in that the method comprises the steps of,

the indwelling cannula (1, 201) has at least one finger stop device (70) at the housing (20) disposed at or near the intermediate tube exit zone (21).

22. The indwelling cannula according to any of the preceding claims,

it is characterized in that the method comprises the steps of,

the intermediate conduit (2022) has one or more reinforcing elements in one or more regions subjected to increased mechanical loading, respectively, by which the bending and/or radial resistance moment of the intermediate conduit (2022) is increased relative to adjacent regions of the intermediate conduit (2022).

23. The indwelling cannula according to any of the preceding claims,

it is characterized in that the method comprises the steps of,

at least the portion of the catheter intermediate tube (2022) that is provided for being placed in the hollow body has at least one spiral-shaped support structure (2027) over the entire length thereof or over a large part of the length thereof, in particular in the form of at least one spiral-wound, internally hollow guide wire, in which the puncture needle (203) can be guided longitudinally displaceably.

24. The indwelling cannula according to claim 23,

it is characterized in that the method comprises the steps of,

the spiral support structure (2027) has at least two spiral or wave-shaped structures, in particular a spiral or wave-shaped structure directed towards the inner side of the catheter intermediate tube (2022) and a spiral or wave-shaped structure directed towards the outer side of the catheter intermediate tube (2022).

25. The indwelling cannula according to any one of claims 23 to 44,

it is characterized in that the method comprises the steps of,

the helical support structure (2027) has a smaller spacing of the coils (2028) relative to each other in a region away from the hollow body than in a region close to the hollow body.

26. The indwelling cannula according to any of the preceding claims,

it is characterized in that the method comprises the steps of,

the intermediate conduit (2022) has lateral through openings (2026) through which liquid can flow from the inside of the intermediate conduit (2022) toward the outside and vice versa.

27. The indwelling cannula according to claim 26,

it is characterized in that the method comprises the steps of,

one, several or all of the lateral through openings (2026) are arranged in the region of the catheter intermediate tube (2022) not covered by the support structure (2027) and/or between the coils (2028) of the helical support structure (2027).

28. The indwelling cannula according to any of the preceding claims,

it is characterized in that the method comprises the steps of,

the indwelling cannula (201) has, in an intermediate tube exit region (2021) in which the catheter intermediate tube (2022) protrudes from a housing (2020) of the indwelling cannula (201), a kink protection structure (2016) which completely or at least partially surrounds the catheter intermediate tube (2022) on the circumferential side, by means of which the risk of kinking of the catheter intermediate tube (2022) in the region of the exit site from the housing (2020) is reduced.

29. The indwelling cannula according to any of the preceding claims,

it is characterized in that the method comprises the steps of,

the housing (2020) of the catheter intermediate tube (2022) has a protection projection (2042) for protecting the catheter intermediate tube (2022), which protection projection extends distally from the intermediate tube exit region (2021) of the housing (2020), wherein between the protection projections (2042) at least on the patient administration side of the indwelling cannula (201) there is at least one guiding slit (2043) extending in the longitudinal direction, which guiding slit is at least as wide as the diameter of the catheter intermediate tube (2022), such that the catheter intermediate tube (2022) can extend in a uniform arc through the guiding slit (2043) when the indwelling cannula (201) is abutted against the patient.

30. The indwelling cannula according to any of the preceding claims,

it is characterized in that the method comprises the steps of,

the indwelling cannula (201) has a gripping region (2044) which is set up for the user to grip the indwelling cannula (201) in the gripping region (2044) during operation.

31. The indwelling cannula according to any of the preceding claims,

it is characterized in that the method comprises the steps of,

The indwelling cannula (201) has at least one finger stop device (2045) at the housing (2020) disposed at or near the intermediate tube exit zone (2021).

32. The indwelling cannula according to any of the preceding claims,

it is characterized in that the method comprises the steps of,

the indwelling cannula (201) has at least one adhesive fastening element for self-adhesively fastening the indwelling cannula (201) at the patient (205).

33. The indwelling cannula according to any of the preceding claims,

it is characterized in that the method comprises the steps of,

the indwelling cannula (201) has at least one fixing wing (2023) or arrangement of fixing wings (2023) coupled to the housing (2020) via a movement mechanism by which the position of the entire fixing wing (2023) or the entire arrangement of fixing wings (2023) relative to the housing (2020) can be adjusted.

34. A puncturing device (301) for puncturing a hollow body by means of a puncturing needle (303), in particular in the form of an indwelling cannula (2, 201) according to any of the preceding claims, wherein the puncturing device (301) has at least one tubular outer sheath (302) in which the puncturing needle (303) can be guided longitudinally displaceably, wherein the outer sheath (302) is set up for pushing over at least a part of the length of the outer sheath and indwelling there for a certain duration after puncturing of the sheath of the hollow body to be punctured has been performed by means of the puncturing needle (303) through the opening of the sheath of the hollow body to be punctured.

35. The lancing apparatus according to claim 34,

it is characterized in that the method comprises the steps of,

the outer envelope (302) and/or a further part of the puncturing device (301) has one or more flow channels extending largely or completely in the longitudinal direction of the puncturing device (301), through which flow channels fluid flowing through the punctured hollow body can flow alongside the outer envelope (302) and/or the further part of the puncturing device (301).

36. The lancing apparatus according to any one of claims 34 to 35,

it is characterized in that the method comprises the steps of,

at the outer side of the outer envelope (302) a barb-like structure is present which makes the pulling out of the piercing device (301) introduced into the hollow body difficult or impeded.

37. The lancing apparatus according to any one of claims 34 to 36,

it is characterized in that the method comprises the steps of,

the outer envelope (302) has an arrangement of a plurality of elongated cavities which extend at least for the most part in the longitudinal direction of the outer envelope (302), wherein the cavities can in particular be formed in the form of capillaries.

38. The lancing apparatus according to any one of claims 34 to 27,

It is characterized in that the method comprises the steps of,

the puncturing device (301) has a further tubular structure which is arranged between the outer sheath (302) and the puncturing needle (303).

39. The lancing apparatus according to any one of claims 34 to 38,

it is characterized in that the method comprises the steps of,

the outer side of the puncture needle (303) and/or the inner side of the outer sheath (302) has a surface layer formed of a material having an increased sliding capacity compared to the remaining material of the puncture needle (303) and/or the outer sheath (302).

40. The lancing apparatus according to any one of claims 34 to 39,

it is characterized in that the method comprises the steps of,

at the outside of the puncture needle (303) and/or at the inside of the outer envelope (302) there is a friction-reducing additive substance, in particular an oil-or fat-containing substance.

41. The lancing apparatus according to any one of claims 34 to 40,

it is characterized in that the method comprises the steps of,

at least the portion of the outer envelope (302) which is provided for being left in the hollow body has a helically wound, internally hollow guide wire over its entire length or a substantial part of its length, in which length the puncture needle (303) can be guided longitudinally displaceably.

42. The lancing apparatus according to any one of claims 34 to 41,

It is characterized in that the method comprises the steps of,

the section of the puncture needle (303) adjacent to the hollow body is duly formed and/or composed of a bioresorbable material, and/or any region of the puncture needle (303) is composed of or coated with a bioresorbable material, and/or at least a portion of the outer sheath (302) is composed of or coated with a bioresorbable material.

43. The lancing apparatus according to any one of claims 34 to 42,

it is characterized in that the method comprises the steps of,

the puncture needle (303) has an external thread and/or the outer sheath (302) has an internal thread.

44. The lancing apparatus according to any one of claims 34 to 43,

it is characterized in that the method comprises the steps of,

the puncturing device (301) has a guide wire which can be guided through the outer sheath (302) or the puncturing needle (303), wherein the guide wire is composed partly, largely or completely of at least one bioresorbable material.

45. The lancing apparatus according to any one of claims 34 to 44,

it is characterized in that the method comprises the steps of,

the piercing needle (303) is rotatable relative to the outer envelope (302) about the longitudinal axis, wherein the piercing device (301) has a holding element (305) by means of which the rotatability of the piercing needle (303) is limited or eliminated at least in a specific longitudinal movement position of the piercing needle (303) relative to the outer envelope (302).

46. The lancing apparatus according to claim 45,

it is characterized in that the method comprises the steps of,

the puncturing device (301) has at least one return spring, by means of which the puncturing needle (303) is held by spring force in a longitudinally displaced position in which the rotatability of the puncturing needle (303) is limited or eliminated.

47. The lancing apparatus according to any one of claims 34 to 46,

it is characterized in that the method comprises the steps of,

at least one component of the puncturing device (301), in particular the outer envelope (302), has at least one marking which can be detected by means of an imaging examination device.

48. The lancing apparatus according to any one of claims 34 to 47,

it is characterized in that the method comprises the steps of,

the outer envelope (302) has a fluid-permeable grid-like, mesh-like or pore-like structure with fine openings which can be closed by a flowing-through blood component during operation of the puncturing device (301).

49. The lancing apparatus according to any one of claims 34 to 48,

it is characterized in that the method comprises the steps of,

at least a portion of the lancing device (301) has an electrically insulating element and/or an electrically conductive element by which an electrically conductive connection is made from one portion of the lancing device (301) to another portion of the lancing device (301).

50. The lancing apparatus according to any one of claims 34 to 49,

it is characterized in that the method comprises the steps of,

the outer envelope (302) has a larger outer diameter in the region close to the hollow body than in the region remote from the hollow body.

51. The lancing apparatus according to any one of claims 34 to 50,

it is characterized in that the method comprises the steps of,

at least one region of the outer envelope (302) has a material that swells by contact with a fluid.

52. The lancing apparatus according to any one of claims 34 to 51,

it is characterized in that the method comprises the steps of,

the lancing device (301) has an automatic blocking mechanism by which the lancet (303) is prevented from being pushed towards the end proximal to the hollow body when the lancet (303) is pulled back from the end proximal to the hollow body within a predetermined range of measurements.

53. The lancing apparatus according to any one of claims 34 to 52,

it is characterized in that the method comprises the steps of,

the outer envelope (302) is configured in multiple layers with one or more removable layers.

54. The lancing apparatus according to any one of claims 34 to 53,

it is characterized in that the method comprises the steps of,

the wall of the outer envelope (302) has at least two spiral or wave-shaped structures, in particular a spiral or wave-shaped structure directed towards the inner side of the outer envelope (302) and a spiral or wave-shaped structure directed towards the outer side of the outer envelope (302).

55. The lancing apparatus according to any one of claims 34 to 54,

it is characterized in that the method comprises the steps of,

the outer envelope (302) has one or more reinforcing elements in one or more regions, respectively, subject to increased mechanical loading.

56. The lancing apparatus according to any one of claims 34 to 55,

it is characterized in that the method comprises the steps of,

the puncturing device (301) has at least one adjusting element, by means of which the flexibility of at least one region of the outer sheath (302) can be adjusted by the user.

57. The lancing apparatus according to any one of claims 34 to 56,

it is characterized in that the method comprises the steps of,

the lancing device (301) has an applicator at the end proximal to the hollow body for applying a substance in the region of the puncture site of the lancet (303) at the hollow body.

58. The lancing apparatus according to any one of claims 34 to 57,

it is characterized in that the method comprises the steps of,

the lancing device (301) has the following mechanism: by means of the mechanism, the outer sheath (302) can be converted into a helical configuration by a relative movement with respect to the puncture needle (303).

59. The lancing apparatus according to any one of claims 34 to 58,

It is characterized in that the method comprises the steps of,

the outer envelope (302) is multi-lumen, wherein two or more lumen are connectable to each other via one or more openings.

60. The lancing apparatus according to any one of claims 34 to 59,

it is characterized in that the method comprises the steps of,

the puncturing device (301) has an automatic advancing mechanism by means of which the outer sheath (302) is automatically advanced into the punctured hollow body, if necessary in relation to at least one external condition, by means of an opening produced by means of the puncturing needle (303).

61. The lancing apparatus according to any one of claims 34 to 60,

it is characterized in that the method comprises the steps of,

the lancing device (301) has a contamination protection device for protecting the end of the lancing device (301) remote from the hollow body from contamination.

62. The lancing apparatus according to any one of claims 34 to 61,

it is characterized in that the method comprises the steps of,

the lancing apparatus (301) has a spring blocking mechanism (3020) for blocking the lancet (303) in the outer sheath (302).

63. The lancing apparatus according to any one of claims 34-62,

it is characterized in that the method comprises the steps of,

the puncture needle (303) has two hollow bodies that are mounted so as to be longitudinally movable relative to one another.

64. The lancing apparatus according to any one of claims 34 to 63,

it is characterized in that the method comprises the steps of,

the outer envelope (302) has two hollow bodies that are supported longitudinally movable relative to each other.

65. The lancing apparatus according to any one of claims 34 to 64,

it is characterized in that the method comprises the steps of,

the outer envelope (302) has lateral through openings through which liquid can flow from the inside of the outer envelope (302) towards the outside and vice versa.