EP3768365A2

EP3768365A2 - Indwelling venous cannula

Info

Publication number: EP3768365A2
Application number: EP19713743.3A
Authority: EP
Inventors: Jens EBNET
Original assignee: Individual
Current assignee: Ebnet Medical GmbH
Priority date: 2018-03-23
Filing date: 2019-03-21
Publication date: 2021-01-27
Also published as: JP2021518224A; CN112236181A; WO2019180148A2; WO2019180148A3; US20210016058A1; DE202018101646U1; KR20200135386A

Abstract

The invention relates to an indwelling venous cannula (1) for application to a living being, comprising a venous catheter (2), wherein a puncture needle (3) can be guided in a longitudinally displaceable manner in the venous catheter (2), wherein at least the part of the venous catheter (2), which is designed to remain in the living being, is formed from a puncture-resistant material or is coated with such a puncture-resistant material over its entire length or most of its length, in which the puncture needle (3) can be guided in a longitudinally displaceable manner.

Description

IV catheter

The invention relates to a venous indwelling cannula for application to a living being with a venous catheter, wherein a puncture needle is längsverschieblich in the vein nenkatheter feasible.

DE 40 41 720 A1 describes a venous indwelling cannula with a venous catheter and a puncture needle displaceable therein, wherein the front part of the venous catheter penetrating into the body is made of stainless steel and the rear part is made of a flexible material, such as a plastic. consists.

Such venous indwelling needles have the disadvantage that the flexible part of the venous catheter can be pierced very easily by contact with the puncture needle and the venous indwelling cannula thus has to be disposed of. In addition, there is a risk that the flexible part of the venous catheter or a part of it shears off by contact with the puncture needle and unnoticed remain in the animal and the ses can endanger. The invention is therefore based on the object to provide an improved venous indwelling. The invention is further based on the object to provide an improved puncture system in the sense of a general puncture system. In principle, it is also possible with the improved venous indwelling cannula to advantageously puncture all body cavities and interstices of the body and all anatomical and diseased structures which are to be punctured, and to insert a catheter into them. The term "venous indwelling cannula" is nevertheless to be retained below, but has a further significance in the sense of a general puncture system, with which not only veins can be punctured. In the following, the term "veins" includes in principle also all body cavities and body interstices and all anatomical and pathological structures which are to be punctured and provided with a catheter.

For example, trachea, pleural space, abdomen, intestine, renal pelvis, urinary bladder and bone can be punctured using the venous indwelling cannula according to the invention. In addition, pathological structures such as abscesses in and on the living being can be punctured.

In this case, the venous indwelling cannula can either be removed directly after puncture or left for some time. Advantageously, arterial blood vessels can also be punctured. Calcified arterial blood vessels can advantageously also be punctured, since the new puncture system is more stable than conventional venous indwelling cannulas and thus controlled, possibly ultrasound-controlled, advancement against resistance is also possible.

The object is achieved with a venous indwelling cannula having the features of claim 1. Advantageous embodiments are described in the subclaims.

It is proposed that at least the part of the venous catheter, which is set up for living in the living being, is made of a puncture-proof material over its entire length or the predominant part of its length, in which the puncture needle is longitudinally movable such a puncture-resistant material is coated. The puncture resistance of the material refers to a possible piercing of the venous catheter through the puncture needle, which is to be prevented by the puncture-proof material. The puncture-proof material can be a metal, also in the form of a metal alloy, or a corresponding puncture-proof plastic material or natural material. Suitable plastic materials include, for example, carbon fiber-reinforced laminate materials, polymers and / or Teflon, also in combination with one another. It is advantageous if the venous catheter by the puncture-proof material not too is stiff, ie still has some flexibility. In addition, can be formed by such materials of the venous catheter MRI / MRI compatible.

The puncture-proof material can no longer be present, in particular in the immediate vicinity of the patient (distal) end of the venous catheter. The thickness of the puncture-proof material and / or the material density need not be constant over the entire longitudinal extent over which the puncture-resistant material is present on the venous retainer, but may vary over the length. The puncture-proof material does not have to be everywhere. There may be deliberately left gaps, e.g. to create a kind of "target kink".

The venous indwelling cannula according to the invention can be used in all areas of medicine, ie not only in the area of veins, but also on arteries or other areas of the anatomy of the human or animal body. In addition, technical systems and containers such as, for example, reservoirs of pumps in and outside of the human or animal body should also be able to be punctured with the venous indwelling cannula according to the invention. It is conceivable, for example, to puncture the reservoirs of insulin and pain pumps for filling them with an active substance. Also conceivable is the puncture of medical port systems. For this purpose, if necessary, the tip of the puncture needle can be designed differently, for example, have a modified grinding. The advantage is that the puncture needle is only used temporarily for the puncture procedure controlled by the user, the venous catheter is then advanced over the puncture needle, and the puncture needle can then be withdrawn directly in a controlled manner. The further steps of the intended application can then be safely carried out via the lying, non-pointed, venous catheter. Due to the novel properties of the venous indwelling cannula according to the invention, the venous catheter does not buckle when it comes to rest as an example in a reservoir. In analogy with what has just been written, fields of application outside medicine are also conceivable. For example, if reservoirs are to be filled with fluids, vapors, or gases, a piercing of the reservoir must occur, but then a puncture needle to avoid damaging the reservoir immediately be withdrawn in a controlled manner and only a non-pointed catheter should remain in the reservoir.

The invention has the advantage that the venous indwelling cannula is puncture, kink and cut firmly formed. The risk of damaging the venous catheter is thereby minimized. The venous indwelling cannula can thus be reused under permanent sterile care in the same living organism, since even if the puncture needle is repeatedly displaced against the venous catheter in the longitudinal direction, the puncture needle can not be damaged by the tip of the puncture needle near the patient. This poses a problem in conventional venous indwelling cannulae. In particular due to already slight application-related bending of the flexible venous catheter, the tip of the puncture needle near the patient can cause shearing of the venous catheter, in particular in the case of repeated advancement of the puncture needle with respect to the venous catheter. of parts of it. This disadvantage of conventional venous indwelling cannulas is overcome by the present invention. This increases patient safety. In addition, the patient comfort is increased because in particular the puncture through the skin is painful and it is possible with the venous indwelling cannula according to the invention, a blood vessel after successful puncture by the skin several times aufzusuchen and thereby with the near-patient parts of the venous indwelling, in particular with the tip of the puncture needle close to the patient to remain permanently below the level of the skin in the animal. This reduces the number of neces- sary punctures in the skin to successfully place a venous indwelling cannula. This reduces the traumatization of the surrounding tissue. In addition, reducing the number of punctures in the skin also reduces the number of possible entry sites for potential pathogens such as bacteria and viruses through the skin.

In addition, the structure and the improved material properties of the venous indwelling cannula according to the invention make it difficult to unintentionally dislocate them from the target structure. Due to the more stable and robust construction, the venous indwelling cannula according to the invention is also particularly suitable for the use of pressure infusions. Further advantages of the invention are:

The venous distribution cannula according to the invention is associated with a reduction in pain when the venous catheter is left on the patient, since the inventive venous distribution cannula can adapt better to the anatomical structures. Vein irritation and phlebitis can be prevented, since the venous indwelling cannula according to the invention substantially less traumatizes the vein or the other blood vessel from the inside, i. the venous wall is less irritated.

- The risk of perforation during advancement of the venous catheter is also reduced in serpentine and / or calcified blood vessels. This is of great advantage, especially for fragile blood vessels, older patients and special risk groups.

The venous indwelling cannula according to the invention makes it possible to vary the strength of the venous catheter located in the blood vessel, since movements of the components in all directions against each other are possible.

- The venous irrigation cannula according to the invention helps to avoid Fehlpunktionen and thus reduce the risk of infection.

- The puncture-proof material also ensures increased safety against kinking of the venous catheter.

- By strengthening the venous catheter through the puncture-proof material, it is also possible to better counteract possible blockage of the venous catheter. Blood can be taken off more easily and permanently. In addition, the traumatization of, for example, corpuscular blood components and hemolysis should be counteracted, since the turbulent flow of the blood in the venous catheter is reduced due to its resistance to kinking. Overall, the venous catheter should have significantly improved flow properties compared to existing venous catheters. The puncture-proof material may be formed, for example, by a tubular metal body or a metal coating of a base material of the venous catheter, which may be a plastic material, for example. The metal may be, for example, steel, eg, stainless steel, or titanium, or an alloy formed therewith, or a bimetal. The puncture-proof material is arranged in an advantageous embodiment of the invention on the inside of the venous catheter, ie, the puncture-proof material forms the inner wall of the venous catheter. A protective layer surrounding the puncture-resistant material to the outside of the venous catheter can for example be formed from plastic.

In an alternative embodiment, the puncture-proof material is arranged on the outer side of the venous catheter. However, it is also conceivable that the puncture-proof material is arranged both on the inner and on the outer side of the venous catheter. The puncture resistant material can thus form either the inner or outer wall of the venous catheter or both.

As a result, the improved venous indwelling cannula is made more stable and robust than hitherto known venous indwelling cannulas with simultaneously improved flexibility of the venous catheter. The puncture-proof material is advantageously designed from a material which has non-thrombogenic properties. Alternatively or additionally, the puncture-proof material may be coated with an additional surface which has non-thrombogenic properties. This material property is intended to prevent the formation of thrombi (blood clots) on the venous catheter. The puncture-proof material may be formed as a metal layer, also as a metal alloy (alloy). Advantageously, the puncture-proof material is also compatible with magnetic resonance tomography (MRT) so that the lying venous catheter or the components of the veniposal cannula inserted in the body remain in the body during an MRI examination and during the MRI examination do not damage and in addition can not dislocate in the magnetic field.

All of the above-mentioned layers of the venous indwelling cannula advantageously have non-thrombogenic properties. In addition, they advantageously have hypoallergenic and / or antimicrobial properties. All layers can also benefit from it be very lubricious material or be coated with such. A refinement of the layers or the surfaces by means of nanotechnological processes is explicitly possible.

According to an advantageous development of the invention, the part of the venous catheter, which is set up for lingering outside of the living being, is formed over its entire length or a substantial part of its length from a puncture-proof material or coated with such a puncture-proof material , The puncture-resistant material can also be in this case both on the inside and on the outside or both on the inside and on the outside. This may be the same puncture-proof material or another puncture-proof material than the puncture-resistant material mentioned in claim 1. In this way, the puncture resistance can also be continued in the parts of the venous indwelling cannula arranged outside the patient's body. In addition, thereby a kinking security of outside of the body arranged parts of the venous indwelling cannula is realized.

In an advantageous development, the venous indwelling cannula is a peripheral venous retention cannula. It is also advantageous if the venous catheter of the peripheral venous indwelling cannula has a stitch length of at least 10 mm, for example 19 mm, and at most 200 mm, for example 50 mm. The venous catheter of the venous indwelling cannula can also have stitch lengths of up to 80, 100, 120 or 600 mm. The puncture needle and the venous indwelling cannula are significantly longer. The stitch length of the venous catheter is the length corresponding to the length of the venous catheter in the living organism. A living being means both human and animal creatures. A venous indwelling cannula according to the invention can be used, in particular in the peripheral region, since the puncture length is so short that a venous catheter made of the puncture-proof material or a venous catheter provided with a coating of puncture-proof material does not have any restrictions during and after application to a living being compared to a conventional venous indwelling cannula and at the same time provides puncture and cut protection on the venous catheter. The field of application of the venous indwelling cannula according to the invention extends to all common venous indwelling cannulas of human medicine including pediatric indwelling indwelling cannulas and those of veterinary medicine. In particular, venous indwelling cannulas having larger diameters than conventional venous indwelling cannulas should also be made possible by the venous indwelling cannula according to the invention. For example, these can be assigned to a defined inner diameter of the venous catheter on the basis of color primers and selected by the operator depending on the application.

The venous indwelling cannula can have at least one holding element for easier application to a living being. Such retaining elements may e.g. be designed as projections of the venous indwelling cannula so that the venous indwelling cannula can be guided by the user with one hand. This facilitates the application, since the user has the other hand e.g. for stabilizing the body part of the living being to be punctured or for operating an ultrasound device.

The venous indwelling cannula can have a fastening element, wherein the fastening element is designed to fix the venous indwelling cannula to the living being. In this way it can be achieved that the venous indwelling cannula can not be accidentally pulled out of the punctured body part of the living being. In addition, the administration of medication is facilitated because the venous indwelling cannula is kept fixed on the patient without being unstable. The venous cannula may be e.g. be fixed via a self-adhesive wound dressing on the fastener to the living being.

It is conceivable that the fastening element has at least one recess, wherein the recess is arranged for guiding a thread. The puncture cannula can thus be fixed to the living being by sewing. In this case, an attachment can be used to exert a pull in the direction of the living being so that the fixation of the venous indwelling cannula can be improved.

It is also conceivable that the function of the fastening element and the retaining element are combined in a single element. Thus, in a first step, the venous indwelling cannula can be accessed by the user via such a combined element After application, the venous indwelling cannula can be fixed to the patient via the combined element.

However, a click / clip mechanism for fixing the puncture system to the skin is also conceivable. By means of a click / clip mechanism, fine skin clips or the fastening element are pressed in the direction of the skin so that the skin clips penetrate into the skin or into the connective tissue of the animal and ensure secure fixation of the venous indwelling cannula. However, a loosening of the venous lumbar cannula can be done at any time by simply pulling the skin clips out of the living being. This process can be repeated as often as a change in position of the venous indwelling cannula or a removal of the same is necessary.

The venous indwelling cannula can have an interposed Y-piece at the end remote from the patient, whereby three-way valves can be mounted on the Y-piece. The three-way valves can be connected to an extension of the Y-piece. However, it is also conceivable that the three-way valves can be connected directly to the Y-piece. This could be done, for example, in the course of a locking element on the Y-piece by a three-way cock can be inserted into a locking element. The Y-piece can be rotatably mounted about its longitudinal axis, so that the Y-piece can be rotated by the user in an advantageous position. A separate storage of three-way valves is also possible, so that a very high flexibility is guaranteed and allows the user optimal operation. The three-way valves can be rotatably mounted, for example, about their own axis. Advantageously, a filter can also be integrated in the three-way valves, which, for example, can prevent the penetration of air, particles or bacteria into the body of a living being.

The venous indwelling cannula can have one or more pressure-sensitive valves which prevent retrograde outflow of fluids and the ingress of air into the venous catheter and thus into the patient's body. Such a pressure-sensitive valve can be designed such that it responds to a specific differential pressure, for example to a pressure difference between arterial and venous pressure. Such a pressure-sensitive valve may be formed, for example, as a check valve. The venous catheter of the venous indwelling cannula can have a wave-shaped surface. A wave-shaped surface is shaped at least in cross-section along the longitudinal axis of the venous catheter by alternating diameters of the venous catheter. A waveform may consist of a sine, rectangular, triangular and / or sawtooth wave, for example. It is also advantageous if the venous catheter has a spiral-shaped structure and / or is provided with a spiral-shaped structure. Due to the spiral-shaped structure, the venous catheter has a high degree of flexibility, making it easier to apply to living beings. Thus, a venous indwelling is provided which is both cut and puncture resistant and flexible.

The venous catheter may be additionally reinforced with further structures or elements, e.g. by transversely, longitudinally or diagonally running structures or elements which can also cover or bridge over a certain distance of the venous catheter and thus counteract a devitrification of the venous catheter. These elements can consist of the puncture-proof material or be formed with a coating of puncture-proof material.

The venous catheter may e.g. Like a coil spring made of a metal, the individual layers can lie close to each other, so that they are in contact with each other, this is similar to the structure of the already known Seldinger wire, which consists of a tightly wound steel wire. Due to the tightly wound layers, the venous catheter is cut-resistant and puncture-resistant, yet at the same time flexible.

Due to the density of the windings and the choice of material of the venous catheter depending on the application, a desired nature, especially in terms of flexibility and stiffness of the venous catheter can be achieved. Thus, in a tightly wound venous catheter, a high rigidity with a high puncture resistance can be achieved. If the venous catheter is wound less tightly, the flexibility increases. When choosing a material, a combination of different metals or other puncture-proof materials can be used. It is conceivable that the density of the windings in case of need of User can be adjusted by the wound venous catheter can be apart or contracted. It is also possible that the density of the windings at different locations of the venous catheter is already different due to the design and thus flexibility and stiffness of the venous catheter, in particular in the longitudinal course, already vary as a result of the design.

It is also conceivable, however, for the venous catheter to have distributed grooves arranged around the circumference, such as e.g. a corrugated tube that provide a wavy surface. Thus, a high flexibility of the venous catheter can be achieved. The grooves run continuously over the entire circumference of the venous catheter and are advantageously arranged parallel in uniform or uneven intervals over the length of the venous catheter. The venous catheter thus has an alternating diameter. In this way, it is possible that the venous catheter can be aligned in different positions. It is also conceivable, however, that the grooves can extend over the circumference in a spiral-shaped manner. Such spiral grooves have the advantage that the pressure loss of a fluid passed through the venous catheter is reduced and, at the same time, swirling of the fluid can be achieved.

It is advantageous if the wave-shaped surface is provided with a sealing coating, in particular a plastic coating. Furthermore, it is advantageous if the coating is a PTFE coating. The sealing coating can be arranged on the outside of the venous catheter. Alternatively, the sealing coating may be disposed on the inside of the venous catheter. Also possible is an arrangement of the sealing coating on the inside and outside of the venous catheter in the sense of a sheath. In addition, the sealing coating can also be embedded in the undulating surface and thus seal it directly in the area of the peripheral surface. The sealing coating forms the venous catheter impermeable to gaseous and / or liquid substances. For example, it can not draw air during aspiration. At the same time, the coating facilitates the introduction of the venous catheter into the punctured body part of the living being. The venous catheter of the venous indwelling cannula can have a dilatation body for uniform widening of a punctured body part at a near-patient end. This has the advantage that the venous catheter can be introduced into the punctured body part of the living organ without additional widening of the puncture site by the dilatation body via the venous catheter or a dilatation body integrated into the venous catheter together with the venous catheter via the puncture needle into the punctured body part is pushed, whereby the necessary dilatation takes place and the venous catheter can be further inserted into the Köperteil.

The dilation body may taper at an acute angle of less than 11 degrees, starting from a 360 ° system. The angle refers to the angular dimension between two external dilation surfaces of the dilation body and not to the central axis of the dilation body.

Advantageously, the dilation body can taper at an acute angle of less than 10.5 degrees. This has the advantage that the venous catheter can be inserted into the punctured body part simply and without additional widening of the puncture site by pushing the dilatation body over the puncture needle into the punctured body part, whereby the necessary dilatation takes place and the venous catheter is inserted into the body part can be. For this it is necessary that the dilatation body tapers at an acute angle of less than 11 degrees, in particular less than 10.5 degrees, so that advancement through the skin during dilation onsvorgang can take place. It is conceivable that the dilation body consists of a material or is coated with a material which reduces the frictional resistance in order to facilitate advancement of the dilatation body. It is also conceivable that after insertion of the dilation body into the punctured body part, it is widened and thus the puncture site widens in such a way that the venous catheter can be inserted into the punctured body part.

The venous catheter of the venous indwelling cannula can have at the near-patient end circumferentially distributed recesses for the homogeneous supply of a fluid into the living being. This has the advantage that, for example, the application of a drug in the body of the living being can be made more homogeneous than in conventional venous indwelling, so that the drug is not on a Place unwanted concentration. In addition, the removal of eg blood or other liquids is better possible, also a drainage of eg secretions or air, depending on the application.

Unlike conventional venous indwelling cannulas, the venous catheter of the venous indwelling cannula according to the invention can also have at least two separate lumens in addition to a single-lumen design. The puncture needle is passed through one of the lumens. This results in a multi-lumen vein indwelling cannula through which different drugs and solutions can be administered simultaneously. By means of recesses or exit holes arranged laterally on the venous catheter, a mixing of different medicaments and solutions can be avoided. By attaching several lateral recesses or exit holes, the flow rates of the applied liquids can be increased. Pressure infusions can be used to advantage. The structure of the puncture-proof material described above can also be adapted to the existence of the lateral exit holes, e.g. annularly around the exit holes to additionally stabilize or open them.

In the multi-lumen design of the venous indwelling cannula, it is possible that the recesses / outlet holes can also be arranged at the top and bottom of the venous catheter. In the case of a multi-lumen design of the venous indwelling cannula, a plurality of connection elements for connecting an aspiration element or a plurality of aspiration elements are also advantageous. As a result, an improved control of the position of the venous indwelling cannula or of the venous catheter, for example in a blood vessel, can be carried out, since the various sections of the venous catheter can be checked for their position in, for example, a blood vessel. This has, for example, a medical relevance in the puncture of deeper blood vessels. By controlling the lumen for blood retrograde, which has its opening in the blood vessel, it can generally be assumed that all other lumens also end up in the blood vessel, because their openings are located even deeper in the blood vessel. The various openings can also each be lined with a material visible in an X-ray image for the exact position control of the openings and thus also for the exact position control of the venous indwelling cannula or the venous catheter be surrounded. The connection element or the connection elements can be arranged on the venous indwelling cannula such that they extend away from the skin of the patient at a certain angle, for example at a 90 degree angle or at a 45 degree angle.

In one embodiment of the venous indwelling cannula in the multi-lumen configuration, for example, only the part of the venous catheter have puncture-proof material in which the puncture needle is guided longitudinally displaceable.

The venous indwelling or venous catheter may contain or be coated with a material over the entire length or at defined locations, which is visible in an X-ray image and thus allows an exact position control of the venous catheter or venous catheter in the body.

The venous catheter of the venous indwelling cannula may have a connection element for connecting an aspiration element, such as an aspiration element. have a syringe. This allows aspiration at any time to check whether the venous catheter is in the target structure of the living being. Thus, e.g. be verified by aspiration of blood, whether the venous catheter of the venous indwelling is still in a blood vessel. Furthermore, such a connection element allows a simplified medication.

Advantageously, the puncture needle of the venous indwelling cannula is a hollow needle. Such a hollow needle already allows the user to aspirate blood during and after the puncture in order to check immediately, during and after the puncture, whether the corresponding vessel has already been correctly punctured.

An expansion body for fixing the venous catheter in the punctured body part can be arranged on the venous catheter of the venous indwelling cannula. Such an expansion body can be designed, for example, as an inflatable cuff, as a so-called cuff, which is arranged, for example, on the outside of the venous catheter. By means of such a cuff, the venous indwelling cannula can be sealed to the outside by inflating the cuff introduced under the skin or filled with liquid and the puncture system is thus sealed to the outside and also advantageously fixed in position.

The venous indwelling cannula can have a hollow extension element, wherein the hollow extension element can be traversed by a fluid in order to reduce the formation of thrombi. If the extension element, and thus the venous catheter, is filled with a fluid, e.g. a saline solution flows through it, it is prevented that thrombi form in the venous catheter, which make it impossible to use the venous cannula.

However, it is also conceivable that a stylet is used, which is arranged within the venous catheter, so that a thrombus formation is prevented.

The venous indwelling cannula may have a securing mechanism designed to shield the tip of the puncture needle after removal of the puncture needle from the venous catheter. Such a shield prevents the user or the living being from being injured at the tip of the puncture needle after it has been pulled out of the venous indwelling cannula after the puncture has taken place.

The puncture needle of the venous indwelling cannula may be surrounded by a protective cap, which is removed before using the venous indwelling cannula. In this way, undesirable injuries during handling of the venous indwelling cannula can be avoided.

By means of the venous indwelling cannula, a local anesthetic and / or antimicrobial substances can be introduced into the body of the patient continuously or for a limited time. As a result, for example, a reduction of pain during insertion or leaving the venous indwelling can be realized.

The venous indwelling cannula may have puncture protection for the puncture needle. The puncture protection, at least in the new state of the venous indwelling cannula, ensures that the user can not injure himself at the tip of the puncture needle. Depth marks may be applied to the venous catheter. The depth markers allow the user to control the insertion depth of the catheter on the patient. The venous catheter may also have a stop ring applied thereto to limit the insertion depth of the catheter to a defined distance.

The invention will be explained in more detail below with reference to an exemplary embodiment using a drawing. It shows:

Figure 1 - A schematic representation of a venous indwelling cannula in a

Side view.

FIG. 1 shows a schematic representation of a venous indwelling cannula 1 in a side view. The venous indwelling cannula 1 has a venous catheter 2, wherein a puncture needle 3 can be guided longitudinally displaceable in the venous catheter 2. The venous indwelling cannula 1 is designed as a peripheral venous indwelling cannula 1. It can be seen that the venous catheter 2, like a tightly wound coil spring, was formed from a puncture-proof material, so that a wave-shaped surface is created. The venous catheter 2 consists over its entire length of a puncture-proof material. Due to the spiral structure, the flexibility of the vein catheter 2 is ensured. Such a design of the venous catheter 2 provides a puncture and cut protection, which protects the venous catheter 2, for example, against puncture by a near-patient tip 6 of the puncture needle 3 in the application of the venous indwelling 1. Thus, the risk of a damaged venous catheter 2 is minimized. This can no longer be sheared off by the catheter-near tip 6 of the puncture needle 3 by repeated displacement of the puncture needle 3 with respect to the venous catheter 2. The committee can be significantly reduced by damaged venous catheters. In addition, a repeated application of the venous indwelling cannula 1 in the context of a puncturing process under permanent sterile conditions on a living being becomes possible. This is particularly important if a malfunction has occurred initially, ie the blood vessel was accidentally missed during the first puncture or the venous catheter 2 could not initially be advanced far enough into the blood vessel. For improved aspiration, the venous catheter 2 is provided with a sealing coating 4. Due to the undulating surface, minimal openings can be created, which make aspiration more difficult because, for example, undesired air can be drawn through these openings. A sealing coating 4 can minimize or prevent the unwanted aspiration of air. Advantageously, the sealing coating 4 is a PTFE coating which at the same time facilitates the insertion of the venous catheter 2 into the punctured body part. By means of an additional dilation element 10 at the proximal end of the venous catheter 2, a uniform widening is achieved when advancing the venous catheter 2 into the punctured body part.

The application of the venous indwelling cannula 1 to a living being can take place, for example, in the following steps:

1 . Puncture of a vein with the puncture needle 3

2. advancing the spiral vein catheter 2 with the sealing coating 4 on the near-patient tip 6 of the puncture needle 3 away into the vein to the desired position

3. Removing / pushing back the puncture needle 3

4. Closing the spiral vein catheter 2 at a patient far end

The venous indwelling cannula 1 has two flattened elements 5. These flattened elements 5 enable the user to operate the venous indwelling cannula 1 with a flange, wherein the second flank can be used for stabilizing the body part to be punctured, for example. The puncture needle 3 is formed as a hollow needle. After puncture by the puncture needle 3 close to the patient, the user can immediately recognize whether the vein has been correctly punctured by filling the hollow puncture needle 3 with venous blood and entering the chamber 7, whereby the blood passes through the blood vessel User can be perceived immediately.

After the puncture has taken place, the venous catheter 2 can be pushed into the punctured body part and the puncture needle 3 together with the chamber 7 can be pulled out of the components of the venous indwelling cannula 1 remaining in the body part. A securing mechanism can be designed so that the near-patient tip 6 of the puncture needle 3 is shielded after withdrawal from the venous indwelling cannula 1 and thus protects the user and the living being from possible puncture injuries.

The venous catheter 2 can be kept fixed in its end position in the punctured body part via fastening elements 8 on the living being. The fixation can be effected by a self-adhesive wound dressing, which fixes the venous indwelling cannula 1 to the living being via the fastening elements 8. The described fasteners 8, e.g. can be designed as wings, are optional elements of the venous indwelling 1.

In this case, the puncture needle can extend substantially in the middle between the holding elements 5 and / or the fastening elements 8.

It becomes clear that the function of the retaining element 5 and of the fastening element 8 can be combined in one element. This allows a simple production of the venous indwelling cannula 1, at the same time keeping the structure of the venous indwelling cannula 1 simple for the user.

A connecting element 9 can be used to connect an aspiration element, for example a syringe. In this case, the connection element 9 can be designed as a valve, which allows a simple medication or aspiration of blood. The valve in the untouched state prevents retrograde leakage of fluids, e.g. In addition, the valve in the pristine state prevents the ingress of air from the outside into the connection element 9. The connection element 9 can also include a filter which allows penetration of coarse particles, bacteria and air into the interior of the connection Connection element 9 and thus prevented in the interior of the venous indwelling.

An aspiration element, such as a syringe, can be connected to the chamber 7. The venous indwelling cannula can thereby be introduced under continuous aspiration with the syringe into a vein. Thus, puncture success can be determined directly and very accurately. Chamber 7 can also be used as a be formed further valve, which allows the flow of fluids in only one defined direction. In addition, chamber 7 may alternatively or additionally be designed in such a way that it prevents the ingress of air and allows air and other gases and vapors to pass only in a defined direction. The chamber 7 may, for example, be formed in the same way as the connection element 9.

The chamber 7 and the connecting element 9 can be covered by a protective cap so that undesired contamination does not occur if the chamber 7 and the connecting element 9 are not used. The protective cap can be connected via a tab to the chamber 7 and / or to the connection element 9.

The venous catheter 2 has recesses 11 arranged distributed around the circumference at the end near the patient. The recesses 11 allow a homogeneous delivery, for example of a medicament, into the living being. It is thus an undesirable locally highly concentrated delivery of the drug into the animal avoided. By arranging a plurality of recesses 11, moreover, the flow rates of the applied infusion solutions and medicaments can be increased. In addition, this may result in aspiration of liquids, e.g. a blood loss, on the lying venous catheter or on the lying venous Vermeer cannula from the living being, be relieved. With a corresponding structure of other components of the venous indwelling cannula, a desired retrograde spontaneous escape of fluids, vapors and / or gases from the venous connective cannula can thereby also be possible, if these are e.g. for draining fluids, vapors and / or gases, in the context of a puncture of the pleural space, other cavities or the body spaces described above to be used.

The present representation is merely a schematic representation, which represents a good overview of the components of the venous indwelling cannula according to the invention. The lengths and proportions may vary in reality. Figure 1 is understood as a possible embodiment. Other forms of teaching according to the invention are furthermore conceivable. Furthermore, the embodiments of the exemplary embodiment are not inseparably linked to one another, so that, for example, the embodiment of the invention is not dependent on the specifically described embodiments of the exemplary embodiment. For example, a variability of the number, length or size of the individual elements is conceivable at any time.

LIST OF REFERENCE NUMBERS

1 venous indwelling cannula

2 venous catheters

3 puncture needle

4 sealing coating

5 retaining element

6 tip

7 chamber

8 fastener

9 connection element

10 dilatation body

1 1 recesses

Claims

1. venous indwelling cannula (1) for application to a living being with a venous catheter (2), wherein a puncture needle (3) is longitudinally displaceable in the venous catheter (2) feasible, characterized in that at least the part of the venous catheter (2 ), which is set up to linger in the living being, is formed over its entire length or the major part of its length, in which the puncture needle (3) is longitudinally displaceable, made of a puncture-proof material or coated with such a puncture-proof material.

2. venous indwelling cannula (1) according to claim 1, characterized in that the venous indwelling cannula (1) is a peripheral venous indwelling cannula (1).

3. venous indwelling (1) according to claim 2, characterized in that the venous catheter (2) of the peripheral venous indwelling cannula (1) has a stitch length of 10 mm to 200 mm.

4. venous indwelling cannula (1) according to one of the preceding claims, characterized in that the venous indwelling cannula (1) has at least one holding element (5) for easier application to the living being.

5. venous indwelling cannula (1) according to any one of the preceding claims, characterized in that the venous indwelling cannula (1) has a fastening element (8), wherein the fastening element (8) is adapted to fix the venous indwelling cannula (1) to the living being.

6. venous indwelling (1) according to one of the preceding claims, characterized in that the venous catheter (2) has a wave-shaped surface.

7. venous indwelling cannula (1) according to claim 6, characterized in that the venous catheter (2) has a spiral-shaped structure and / or is provided with a spiralförmi- structure.

8. venous indwelling cannula (1) according to claim 6 or 7, characterized in that the wave-shaped surface with a sealing coating (4), in particular a plastic coating, is provided.

9. venous indwelling cannula (1) according to claim 8, characterized in that the sealing coating (4) is a PTFE coating.

10. venous indwelling cannula (1) according to any one of the preceding claims, characterized in that the venous catheter (2) at a near-the patient end has a dilation body (10) for uniform expansion of a dotted body part.

11. venous indwelling cannula (1) according to any one of the preceding claims, characterized in that the venous catheter (2) at the near-patient end distributed over the circumference arranged recesses (11) for the homogeneous supply of a fluid in the living being has.

12. venous indwelling cannula (1) according to any one of the preceding claims, characterized in that the venous catheter (2) has a connection element (9) for the connection of an aspiration element.

13. venous indwelling cannula (1) according to any one of the preceding claims, characterized in that the puncture needle (3) is a hollow needle.

14. venous indwelling cannula (1) according to any one of the preceding claims, characterized in that on the venous catheter (2) an expansion body for La fixixierung the Venenkatethers (2) is arranged in the punctured body part.

15. venous indwelling cannula (1) according to any one of the preceding claims, characterized in that the venous indwelling cannula (1) has a hollow extension element, wherein the hollow extension member to reduce a thrombus formation is flowed through by a fluid.

16. venous indwelling cannula (1) according to any one of the preceding claims, characterized in that the venous indwelling cannula (1) has a securing mechanism which, after removal of the puncture needle (3) from the venous catheter (2), the tip (6) shield the puncture needle (3).