CN214285098U

CN214285098U - Puncture auxiliary device

Info

Publication number: CN214285098U
Application number: CN202022366090.XU
Authority: CN
Inventors: 张庭超; 张伟伟
Original assignee: Hangzhou Valgen Medtech Co Ltd
Current assignee: Hangzhou Valgen Medtech Co Ltd
Priority date: 2020-10-21
Filing date: 2020-10-21
Publication date: 2021-09-28
Anticipated expiration: 2030-10-21

Abstract

The application provides a puncture auxiliary device for supplementary medical instrument puncture tissue. The puncture auxiliary device comprises a sealing part, a flexible capsule body and a puncture part, wherein the near end of the flexible capsule body is connected with the sealing part in a sealing way, the far end of the flexible capsule body is connected with the puncture part in a sealing way, and the sealing part, the flexible capsule body and the puncture part are axially communicated and form a channel; the medical instrument is movably inserted in the channel; the sealing part is in interference fit with the part of the medical instrument inserted in the channel, and the flexible capsule body and the puncture part are in clearance fit with the part of the medical instrument inserted in the channel. This puncture auxiliary device adjusts laborsaving convenient and can reduce the risk of sealed inefficacy.

Description

Puncture auxiliary device

Technical Field

The application relates to the technical field of medical instruments, in particular to a puncture auxiliary device.

Background

The mitral valve is a one-way "valve" between the Left Atrium (LA) and the Left Ventricle (LV), which ensures blood flow from the left atrium to the left ventricle. A normal healthy mitral valve has a plurality of chordae tendineae. The valve leaves of the mitral valve are divided into an anterior leaf and a posterior leaf, when the left ventricle is in a diastole state, the two are in an opening state, and blood flows from the left atrium to the left ventricle; when the left ventricle is in a contraction state, the chordae tendineae are stretched to ensure that the valve leaflets are not flushed to the atrium side by blood flow, and the anterior and posterior leaflets are closed well, thereby ensuring that blood flows from the left ventricle to the aorta through the aortic valve (AV for short). If the chordae tendineae or papillary muscles are diseased and the chordae tendineae of the anterior leaflet or posterior leaflet break, the mitral valve will not return to the closed state as it would in the normal state when the left ventricle is in the contracted state, and the impulse of the blood flow will further cause the leaflets to fall into the left atrium, causing regurgitation.

Mitral valve repair or replacement is an option to reduce and treat mitral regurgitation depending on the degree of mitral valve pathology and the health of the patient. In order to repair or replace the mitral valve, the conventional surgical open heart operation, percutaneous transcatheter approach or transapical approach can be selected for accessing the mitral valve focus, wherein the transapical approach means that an opening is punctured in the cardiac apex, and a channel for a diagnosis and treatment instrument to enter the mitral valve focus is formed through the opening, so that the approach is a more minimally invasive and safe intervention approach.

There is a prior art apical puncture assistance device comprising a main body including a silicon washer fitted within its proximal end, the silicon washer having an internal opening, and an inner lumen. When the puncture needle or the related implantation or repair instrument is pushed into the inner lumen from the inner opening, the silicon gasket is controlled to be compressed, so that the diameter of the inner opening is reduced, and the silicon gasket can hold any instrument pushed through the inner opening tightly to realize the sealing of the inner lumen. In the case that the instrument in which the silicon gasket is held forms a sealed state, when the instrument needs to move axially or rotate axially to adjust the position, the instrument needs to move relative to the silicon gasket. On one hand, the instrument and the silicon washer have larger acting force, and the resistance borne by the instrument and the silicon washer is larger when the instrument and the silicon washer move relatively, so that the correspondingly required driving force is larger and is not easy to adjust; on the other hand, relative movement between the tool and the silicone gasket can cause repeated rubbing of the two, which can cause the silicone gasket to tear and the seal to fail.

SUMMERY OF THE UTILITY MODEL

The technical problem that this application will be solved lies in providing one kind and adjusts laborsaving convenient and can reduce the puncture auxiliary device of sealed inefficacy risk.

In order to achieve the above purpose, the embodiment of the present application adopts the following technical solutions:

a puncture auxiliary device is used for assisting a medical instrument to puncture tissues and comprises a sealing part, a flexible bag body and a puncture part, wherein the near end of the flexible bag body is connected with the sealing part in a sealing way, the far end of the flexible bag body is connected with the puncture part in a sealing way, and the sealing part, the flexible bag body and the puncture part are axially communicated and form a channel; the medical instrument is movably inserted in the channel; the sealing part is in interference fit with the part of the medical instrument inserted in the channel, and the flexible capsule body and the puncture part are in clearance fit with the part of the medical instrument inserted in the channel.

In an embodiment, the sealing component includes a connecting cylinder and a limit sealing element, the limit sealing element is accommodated in the connecting cylinder, an inner wall of the limit sealing element is in interference fit with a portion of the medical instrument inserted into the channel, and the flexible balloon is in sealing connection with a distal end of the connecting cylinder.

In an embodiment, the sealing member further includes a proximal screw cap, the proximal screw cap is detachably connected to the proximal end of the connector barrel and partially extends into the connector barrel, an outer wall of the position limiting sealing member abuts against an inner wall of the proximal screw cap, and an outer diameter of the position limiting sealing member increases from the proximal end to the distal end.

In an embodiment, the sealing component further includes an elastic gasket disposed in the connecting cylinder, the limit sealing element abuts against between the proximal end cap and the elastic gasket, a slit is disposed on the elastic gasket, and a size of the slit is smaller than or equal to a maximum outer diameter of the medical instrument.

In one embodiment, the sealing member further comprises a distal screw cap removably attached to the distal end of the connector barrel, the proximal end of the flexible balloon being sealingly secured between the connector barrel and the distal screw cap.

In one embodiment, the proximal end of the flexible balloon is connected to a first annular flange that is clamped between the distal end of the connector barrel and the distal screw cap.

In an embodiment, the sealing member further comprises a first rotation stop gasket, the first rotation stop gasket is sleeved outside the proximal end of the flexible balloon body, and the first rotation stop gasket is clamped between the first annular flange and the distal end screw cap.

In one embodiment, the interference between the inner wall of the stop seal and the maximum outer diameter of the medical instrument is in the range of [0.5,1.0] mm.

In an embodiment, the puncturing part includes a puncturing body and a joint detachably connected to the proximal end of the puncturing body, the distal end of the flexible balloon is hermetically fixed between the proximal end of the puncturing body and the joint, the puncturing body is axially provided with an opening, and the inner wall of the opening is in clearance fit with the part of the medical instrument inserted in the channel.

In one embodiment, the distal end of the flexible balloon is connected to a second annular flange that is clampingly secured between the proximal end of the piercing body and the adapter.

In one embodiment, the piercing member further comprises a second rotation stop washer, the second rotation stop washer is sleeved on the distal end of the flexible balloon, and the second rotation stop washer is clamped between the second annular flange and the joint.

In an embodiment, the puncture member further includes a spiral needle sleeved on the outer circumference of the puncture body, the proximal end of the spiral needle is fixedly connected with the proximal end of the puncture body, and the spiral needle extends spirally towards the distal end of the puncture body along the axial direction of the puncture body.

In one embodiment, the distal end of the helical needle terminates between the proximal end of the piercing body and the distal end of the piercing body.

In one embodiment, the flexible bladder has a generally olive, cylindrical, frustoconical or bellows-like shape.

In one embodiment, the flexible bladder is made of a flexible material having a young's modulus in a range of 0.02MPa to 0.4 MPa.

In one embodiment, the flexible material is latex or nitrile rubber, and the wall thickness of the flexible bag body ranges from 0.2mm to 2 mm.

In one embodiment, a support structure is disposed within the flexible bladder, and the flexible bladder encapsulates the support structure.

In one embodiment, the support structure is in the form of a mesh, a helix, or a ring.

In one embodiment, the puncture assist device further comprises a dilator movably disposed through the channel with a distal end of the dilator exposed from the distal end of the puncture member.

In the puncture auxiliary device provided by the embodiment of the application, due to the arrangement of the flexible capsule body, when the diagnosis and treatment instrument is arranged in the inner channel of the puncture auxiliary device in an axial and/or radial adjusting position in a penetrating mode, the diagnosis and treatment instrument and the sealing part can move and/or rotate synchronously, and the flexible capsule body deforms to conform to the axial movement and/or the axial rotation of the diagnosis and treatment instrument. During adjustment of the medical instrument, only negligible resistance is experienced due to deformation from the flexible balloon.

Compared with the conventional puncture auxiliary device introduced in the background art, the puncture auxiliary device provided by the embodiment of the application has the advantages that on one hand, when the position of a diagnosis and treatment instrument is adjusted, the required driving force is small, and the operation is labor-saving and convenient; on the other hand, in the process of adjusting the medical instrument, the medical instrument and the sealing part can move synchronously, relative movement is not generated between the medical instrument and the sealing part, and friction between the medical instrument and the sealing part is reduced, so that the risks of tearing and sealing failure of the sealing part can be reduced.

Drawings

Fig. 1 is a schematic perspective assembly view of a puncture assistance device according to a first embodiment of the present application;

FIG. 2 is a side view of FIG. 1;

FIG. 3 is a cross-sectional view of a portion of the structure of the puncture assist device of FIG. 1;

fig. 4 is a cross-sectional view of the medical instrument inserted into the sealing member of the puncture aid;

fig. 5 is a sectional view of the medical instrument inserted into the flexible bag of the puncture aid;

fig. 6 is a sectional view of the medical instrument inserted into the puncture part of the puncture assisting device;

FIGS. 7-19 are schematic views of various configurations of flexible bladders in a penetration assisting device;

FIG. 20 is an exploded perspective view of the puncture assist device shown in FIG. 3;

FIG. 21 is an exploded perspective view of the seal member;

fig. 22 is a sectional view of a part of the structure of the seal member;

FIG. 23 is a schematic cross-sectional view of an elastomeric gasket;

FIGS. 24, 25 and 26 are schematic views of different structural forms of slits of the elastic gasket;

figure 27 is a cross-sectional view of the sealing member attached to the proximal end of the flexible balloon;

FIG. 28 is an exploded perspective view of the puncturing member;

FIG. 29 is a cross-sectional view of the puncturing member;

FIG. 30 is a cross-sectional view of the piercing member and the distal end of the flexible balloon attached together;

FIG. 31 is a perspective view of the dilator;

FIG. 32 is a schematic view of a dilator threaded into the puncture assist device and punctured into the heart;

FIG. 33 is a schematic view of the puncture member of the puncture assist device according to the first embodiment being held by the apical pouch;

FIG. 34 is an enlarged, fragmentary view of FIG. 33;

FIG. 35 is a schematic view of a transapical medical instrument being inserted into the puncture assist device and advanced into the heart to an initial position, as provided by the first embodiment;

FIG. 36 is a schematic view of the first embodiment providing a puncture assistance device for axially adjusting a transapical medical instrument into position;

FIG. 37 is a schematic view of the first embodiment of the transapical medical instrument after it has been removed from the puncture aid;

fig. 38 is a perspective view of a puncture device of a puncture assisting apparatus according to a second embodiment;

FIG. 39 is a perspective view of the lancing member illustrated in FIG. 38 from another perspective;

FIG. 40 is a schematic view of a second embodiment of a puncture assist device with a dilator threaded therethrough and into a heart.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more clear, the present application will be further described in detail with reference to the accompanying drawings.

It should be understood that expressions such as "include" and "may include" that may be used in the present application indicate the presence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In the present disclosure, terms such as "including" and/or "having" may be interpreted as indicating specific characteristics, numbers, operations, constituent elements, components, or combinations thereof, but may not be interpreted as excluding the existence or addition possibility of one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.

Further, in this application, the expression "and/or" includes any and all combinations of the associated listed words. For example, the expression "a and/or B" may include a, may include B, or may include both a and B.

In the present application, expressions including ordinal numbers such as "first" and "second" and the like may modify the respective elements. However, such elements are not limited by the above expression. For example, the above description does not limit the order and/or importance of the elements. The above expressions are only used to distinguish one element from another. A first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of the present disclosure.

When a component is referred to as being "connected" or "accessed" to other components, it should be understood that: not only may the component be directly connected or accessed to the other component, but there may also be another component between the component and the other component. On the other hand, when components are referred to as being "directly connected" or "directly accessing" other components, it is understood that no components exist therebetween.

In the field of interventional medical device technology, a position close to the operator is generally defined as proximal and a position far from the operator as distal. The direction of the central axis of rotation of an object such as a cylinder or a pipe is defined as the axial direction. Radial refers to a direction through an axis in a radial plane, e.g., a straight direction along a diameter or radius, or a straight direction perpendicular to the axis.

Referring to fig. 1 and 2, in conjunction with fig. 32, 35 to 37, a first embodiment of the present application provides a puncture assisting apparatus 100 for puncturing living tissue and providing a puncture channel for a medical instrument 200 (shown in fig. 4), so as to assist the medical instrument 200 in diagnosing or treating a lesion in the living tissue. In this embodiment, the living tissue is a heart, and the puncture assisting device 100 is used for puncturing an apex of the heart to provide a passage for a valve repair and/or replacement apparatus to enter a focus of the heart. It is understood that the puncture assisting device 100 is not limited to be used for puncturing the apex of the heart and puncturing the medical instrument 200 to repair or replace the diseased mitral valve, and the puncture assisting device 100 can also be used for puncturing other living tissues needing medical diagnosis besides the apex of the heart.

Referring to fig. 1 to 3, the puncture assisting device 100 includes a sealing member 10, a flexible capsule 30 and a puncture member 50 connected in sequence from a proximal end to a distal end. The proximal end of the flexible balloon 30 is sealingly connected to the sealing member 10 and the distal end of the flexible balloon 30 is sealingly connected to the piercing member 50. The sealing member 10, the flexible bladder 30 and the piercing member 50 are in communication along the axial direction of the piercing aid 100 and form a channel 101. In other words, the sealing member 10, the flexible capsule 30 and the puncturing member 50 are axially penetrated in the puncturing aid 100, so that a passage 101 is formed in the puncturing aid 100, and the medical instrument 200 is movably inserted into the passage 101. Referring to fig. 4, the sealing member 10 may be configured to have an interference fit with the medical instrument 200 after the medical instrument 200 is advanced into the passageway 101. Referring to fig. 5 and 6, the flexible bladder 30 and the penetrating member 50 are both capable of clearance-fitting with the medical instrument 200 after the medical instrument 200 is advanced into the passage 101. In other words, the sealing member 10 is in interference fit with the portion of the medical instrument 200 inserted into the channel 101, and the flexible balloon 30 and the penetrating member 50 are in clearance fit with the portion of the medical instrument 200 inserted into the channel 101. The flexible balloon 30 is capable of radial expansion, axial compression and axial twisting for adjusting the position of a medical device 200 (e.g., a valve repair and/or replacement device) threaded into the passage 101.

Due to the flexibility of the flexible bladder 30, when the medical instrument 200 inserted into the internal passage 101 of the puncture assistance device 100 is adjusted in position in the axial and/or radial direction, the interference-fit medical instrument 200 and the sealing member 10 can move or/and rotate synchronously, and the flexible bladder 30 deforms to conform to the axial movement and/or axial rotation of the medical instrument 200. During adjustment of the medical instrument 200, the medical instrument 200 is only subjected to negligible resistance from deformation of the flexible bladder 30. Compared with the existing puncture auxiliary device, on one hand, when the position of the diagnosis and treatment instrument 200 is adjusted, the required driving force is small, and the operation is labor-saving and convenient; on the other hand, in the process of adjusting the medical instrument 200, the medical instrument 200 and the sealing member 10 can move synchronously without relative movement between the two, so that friction between the two is reduced, and the risk of tearing and sealing failure of the sealing member 10 is reduced.

In this embodiment, referring to fig. 7, 8 and 9, the flexible balloon 30 is substantially olive-shaped, the middle of the flexible balloon 30 is thicker, and the proximal end of the flexible balloon 30 and the distal end of the flexible balloon 30 are thinner. The proximal end of the flexible capsule 30 is connected with the sealing part 10 in a sealing way, and the distal end of the flexible capsule 30 is connected with the puncture part 50 in a sealing way. The flexible balloon 30 includes a hollow structure that is axially retractable and radially expandable to receive the medical instrument 200 therethrough. The surface of the flexible bladder 30 is a dense structure without voids. The flexible capsule 30 is made to be non-cracking and non-leakage under the water pressure of [3.0,3.2] MPa by setting the wall thickness to be enough or by adding a biocompatible dense additive into the flexible material for manufacturing the flexible capsule 30, so that the flexible capsule can sufficiently bear the blood pressure. The material for making the flexible bag 30 is preferably a biocompatible flexible material with Young's modulus of 0.02,0.40 MPa, such as latex, nitrile rubber, etc. The wall thickness of the flexible balloon 30 is in the range of 0.2, 2mm, so that the flexible balloon 30 is easily deformed to adjust the position of the medical instrument 200 and can withstand the blood pressure without rupture.

After the medical instrument 200 is inserted into the axial channel 101 of the sealing member 10, the flexible balloon 30 and the puncturing member, when the position of the medical instrument 200 is adjusted, because the medical instrument 200 is in interference fit with the sealing member 10, the acting force capable of driving the relative movement between the medical instrument 200 and the sealing member 10 is far greater than the acting force capable of deforming the flexible balloon 30, so that a small driving force is applied to the proximal end of the medical instrument 200 to enable the medical instrument 200 and the sealing member 10 to synchronously move and/or rotate, the flexible balloon 30 is made of a flexible material, the flexible balloon 30 has the characteristics of easy expansion and easy torsion, and under the small driving force, the flexible balloon 30 can deform along with the synchronous movement of the medical instrument 200 and the sealing member 10 to adjust the axial and/or radial position of the medical instrument 200, labor saving and convenience; moreover, when the flexible balloon 30 is used for apical puncture, if the distal end of the medical instrument 200 touches the chordae tendinae or the valve leaflets, the operator can easily determine that the source of the resistance is caused by the instrument touching the chordae tendinae or the valve leaflets, so as to prompt the operator to stop moving the medical instrument 200 and avoid damaging the valve leaflets or the chordae tendinae.

The proximal end of the flexible bladder 30 is also connected to a first annular flange 31 (as shown in figures 7 to 9), the flexible bladder 30 being sealingly connected to the sealing member 10 by the first annular flange 31. The distal end of the flexible bladder 30 is also connected to a second annular flange 33 (as shown in fig. 7-9), and the flexible bladder 30 is sealingly connected to the piercing member 50 via the second annular flange 33. The first annular flange 31 and the second annular flange 33 are also made of a flexible material so as to be deformable when being pressed by an external force, thereby improving the sealing performance between the flexible bag body 30 and the sealing member 10 and the sealing performance between the flexible bag body 30 and the puncture member 50. It is understood that the first annular flange 31 and the second annular flange 33 may be formed by rolling the proximal end and the distal end of the flexible balloon 30, i.e. integrally with the flexible balloon 30, or the first annular flange 31 and the second annular flange 33 may be separately manufactured and then fixedly connected to the proximal end and the distal end of the flexible balloon 30, respectively, without limitation.

It will be appreciated that the flexible bladder 30 may also be generally cylindrical in shape (or straight cylindrical, as shown in fig. 10 and 11), since the cylindrical flexible bladder 30 has a smaller lumen volume, the blood output of the patient may be reduced; the flexible balloon 30 may also be of a frustoconical configuration (as shown in fig. 12, 13 and 14) with a large proximal diameter and a small distal diameter, which may have superior axial contractibility and radial torqueability.

It should be understood that, referring to fig. 15, the flexible bag 30 may further be wrapped with a supporting structure 60, the supporting structure 60 is a net structure, and the flexible bag 30 and the supporting structure 60 may be connected by sewing or bonding. The support structure 60 may be formed of multiple sections connected together to form a single unit, or may be formed integrally.

It is understood that the support structure 60 can be fixed on the inner side of the flexible bladder 30, for example, referring to fig. 16, 17 and 18, the flexible bladder 30 is a bellows-shaped structure, the cross section of the flexible bladder 30 along the axial direction is a generally saw-tooth structure, the flexible bladder 30 includes a plurality of peaks 35 and a plurality of valleys 37, the support structure 60 includes a plurality of supports 61, the supports 61 are disposed at the peaks 35 and the valleys 37, and the supports 61 are fixedly connected with the flexible bladder 30 (e.g., the inner side). The support body 61 is an annular structure arranged in a radial direction of the flexible bladder 30. The plurality of supporting bodies 61 are connected to each other or not connected to each other (i.e., provided independently of each other). Alternatively, the support structure 60 comprises support wires (not shown) arranged along the axial direction of the flexible bladder 30. As shown in fig. 19, the support structure 60 may also be in the form of a spring wound from a relatively soft wire.

In the case of the supporting structure 60, the flexible bag body 30 may be used as a film of the supporting structure 60, and the material of the flexible bag body 30 may be polyethylene terephthalate (PET), Polytetrafluoroethylene (PTFE), polyether block amide resin (PEBAX), or the like. The support structure 60 may be woven from wire or cut from a metal tube of a shape memory alloy material selected from the group consisting of nickel titanium alloy, cobalt chromium alloy, and the like. The supporting structure 60 may also be formed by weaving and surrounding a high polymer material with certain elasticity and hardness, such as Polycarbonate (PC), Acrylonitrile Butadiene Styrene (ABS), Polyamide (PA), etc. It is to be understood that the material of the support structure 60 is not limited.

Because the flexible balloon 30 is supported by the supporting structure 60, the supporting strength and the tearing strength of the flexible balloon 30 are enhanced, so that the expansion range of the flexible balloon 30 can be prevented from exceeding the limit due to ventricular hypertension, and the risk of rupture of the flexible balloon 30 is reduced.

Referring to fig. 20, 21 and 22, the sealing member 10 includes a connecting cylinder 11, an elastic gasket 13, a limiting sealing element 15 and a proximal screw cap 17. The elastic gasket 13 and the limit sealing element 15 are fixedly accommodated in the near end of the connecting cylinder 11 through the near end screw cap 17, and the near end of the flexible capsule 30 is hermetically fixed at the far end of the connecting cylinder 11.

The connecting cylinder 11 is provided with a through hole 111. The inner wall of the proximal end of the through hole 111 is provided with a first abutting portion 113 (as shown in fig. 21). In this embodiment, the through hole 111 is a stepped hole to form the first abutting portion 113, and the inner diameter of the through hole 111 increases from the proximal end to the distal end. It can be understood that the through hole 111 may not be a stepped hole, and the first abutting portion 113 is a convex portion protruding from the wall of the through hole 111; the aperture of the through hole 111 is not limited, that is, the aperture of the through hole 111 increases from the proximal end to the distal end, for example, the through hole 111 may be a uniform aperture.

The elastic pad 13 is accommodated in the proximal end of the connecting cylinder 11 and abuts against the first abutting portion 113. The elastic gasket 13 serves to seal the passage 101 from the outside when the medical instrument 200 is not inserted into the axial passage 101 of the sealing member 10, and to maintain the passage 101 in a sealed state. Referring to fig. 23, the elastic pad 13 includes an elastic portion 131 and a connecting portion 133 formed by bending and extending an edge of the elastic portion 131. The elastic portion 131 abuts against the first abutting portion 113, and the connecting portion 133 extends toward the proximal opening of the connecting cylinder 11. The flexible portion 131 is provided with a slit 135 (fig. 21) for insertion of an instrument (e.g., a medical instrument 200 or a dilator), and the size of the slit 135 is smaller than or equal to the maximum outer diameter of the instrument. The slit 135 is in a closed position when no instrument is inserted. Since the slit 135 is in a closed state when the channel 101 is not penetrated by any instrument, the channel 101 in the axial direction of the sealing member 10 is in a closed state, i.e. a sealed state is formed, thereby achieving the sealing of the sealing member 10 with the flexible capsule 30 and the puncturing member 50 in the axial direction of the channel 101. It is understood that the connection portion 133 may be omitted from the elastic pad 13.

More specifically, when the medical instrument 200 is not inserted and passes through the elastic gasket 13, the elastic gasket 13 is in a natural sealing state, that is, the elastic gasket 13 can recover to its original shape without external force, and thus the original sealing state is maintained. When the medical instrument 200 is inserted into the elastic gasket 13, the elastic gasket 13 is in an interference fit with the medical instrument 200 (please refer to fig. 4), so that the interference fit between the sealing member 10 and the medical instrument 200 can be further enhanced, and when the position of the medical instrument 200 is adjusted, there is no relative movement between the medical instrument 200 and the sealing member 10. The elastic pad 13 may be made of elastic material such as silica gel, nitrile rubber, etc. In the present embodiment, the slit 135 extends at least partially in the axial direction of the center of the elastic pad 13 and penetrates the elastic pad 13. It is to be understood that the shape of the slits 135 is not limited, and the slits 135 may be straight slits (as shown in fig. 24), star slits (as shown in fig. 25), cross slits (as shown in fig. 26), and the like.

Referring to fig. 4 and 22, the stop seal 15 is received in the connecting portion 133 to clamp the outer wall of the medical instrument 200 inserted through the axial passage 101 of the sealing member 10 to perform sealing. The inner wall of the curb seal 15 can be interference fit with the medical instrument 200 after the medical instrument 200 is advanced into the channel 101. The material of the confinement seal 15 may include, but is not limited to, an elastomeric material such as silicone, latex, etc. When the medical instrument 200 is inserted into the entire axial passage 101 of the puncture assisting device 100 and the position of the medical instrument 200 is adjusted, due to the interference fit between the position-limiting sealing member 15 and the medical instrument 200, a large extrusion force and a large friction force exist between the position-limiting sealing member 15 and the medical instrument 200, when only the proximal end of the medical instrument 200 moves axially or/and rotates axially, the flexible balloon 30 is compressed axially or/and twisted axially, and the medical instrument 200 and the sealing member 10 do not move relatively, and the two devices can move or/and rotate synchronously, so that on one hand, the adjustment is easy, the required driving force is small, on the other hand, the friction of the medical instrument on the position-limiting sealing member 15 in the adjustment process is reduced, and the risk of seal failure is reduced. Preferably, the interference between the inner wall of the packing 15 and the maximum outer diameter of the medical instrument 200 is in the range of [0.5,1.0] mm.

A proximal screw cap 17 is removably secured to the proximal end of the connector barrel 11 and extends partially into the connector barrel 11. The outer wall of the limit sealing element 15 is abutted against the inner wall of the proximal screw cap 17, and the outer diameter of the limit sealing element 15 is gradually increased from the proximal end to the distal end.

More specifically, the limiting sealing element 15 is of a generally truncated cone structure, and the outer diameter of the limiting sealing element 15 increases progressively from the proximal end to the distal end; the proximal screw cap 17 is provided with a through hole 171, the cross section of the through hole 171 is approximately in a truncated cone structure, the aperture of the through hole 171 increases gradually from the proximal end to the distal end, and the hole wall of the through hole 171 is abutted against the outer wall of the limit sealing element 15. The bore size of the proximal end of the through bore 171 is smaller than the minimum outer diameter of the stop seal 15 to prevent the stop seal 15 from backing out of the proximal end of the through bore 171 of the proximal screw cap 17. The proximal screw cap 17 is provided with a first annular groove 173, and the first annular groove 173 is disposed around the through hole 171. The proximal end of the connector barrel 11 and the connection 133 of the resilient gasket 13 are secured in the first annular groove 173. In this embodiment, an external thread (not shown) is provided on an outer wall of the proximal end of the connection cylinder 11, an internal thread (not shown) is provided on a side wall of the first annular groove 173, the external thread of the proximal end of the connection cylinder 11 is engaged with the internal thread of the first annular groove 173, so that the proximal screw cap 17 is fixed to the proximal end of the connection cylinder 11, and the connection portion 133 is fixedly clamped between the connection cylinder 11 and the proximal screw cap 17. When the sealing component 10 is assembled, when the internal thread of the proximal end of the connecting cylinder 11 and the external thread of the proximal end screw cap 17 are gradually screwed, the limit sealing element 15 and the elastic gasket 13 are extruded, so that good sealing and connection are formed between the proximal end screw cap 17 and the proximal end of the connecting cylinder 11, and the assembly of the sealing component 10 is facilitated while high sealing performance of the sealing component 10 is ensured. It will be appreciated that the connection barrel 11 and the proximal cap 17 are not limited to a fixed connection by threaded engagement, but may be fixed by means such as a snap connection or the like, without limitation.

It will be appreciated that the proximal cap 17 and the resilient gasket 13 of the sealing member 10 may be omitted and the stopper seal 15 may be directly fixedly received in the through hole 111 of the connector barrel 11.

The sealing member 10 further comprises a distal cap 18 detachably connected to the distal end of the connecting cylinder 11, and the proximal end of the flexible balloon 30 is hermetically fixed between the connecting cylinder 11 and the distal cap 18, so as to facilitate the assembly and disassembly of the flexible balloon 30 and the connecting cylinder 11.

The limit sealing element 15 and the elastic gasket 13 of the sealing member 10 can be in interference fit with the medical instrument 200, so that the medical instrument 200 and the sealing member 10 can move relatively to each other to overcome a large resistance. By adjusting the interference magnitude or/and the contact area between the limit sealing element 15, the elastic gasket 13 and the medical instrument 200, the sealing component 10 can be ensured to be axially subjected to the interference magnitude or/and the contact area of [3.0,3.2]]The sealing member 10 does not move relative to the medical instrument 200 in the axial direction under the MPa pressure. Preferably, the interference is in the range of [0.5,1.0]]mm, the contact area is in the range of [80.0,100.0 ]]mm². It is understood that the range of the interference between the elastic pad 13 and the medical instrument 200 is not limited, and the contact area between the elastic pad 13 and the medical instrument 200 is not limited.

When the medical instrument 200 rotates around the axial direction, the sealing member 10 connected to the medical instrument 200 in an interference fit manner rotates synchronously, and the distal end of the sealing member 10 transmits a radial torsional force to the flexible balloon 30, so that the flexible balloon 30 is torsionally deformed in compliance with the rotation direction of the medical instrument 200. In this embodiment, the axial rotation angle of the medical instrument may be in a range of [0 ° or 360 ° ].

Referring to fig. 27, the sealing member 10 further includes a first rotation stopping gasket 19 received in the distal end of the through hole 111, the first rotation stopping gasket 19 is sleeved outside the proximal end of the flexible balloon 30, and the first rotation stopping gasket 19 is clamped between the first annular flange 31 and the distal end screw cap 18, so that the first annular flange 31 is clamped and fixed between the distal end of the connecting cylinder 11 and the distal end screw cap 18. The first anti-rotation spacer 19 serves to prevent the flexible bladder 30 from rotating relative to the connector barrel 11.

Specifically, the inner wall of the distal end of the through hole 111 of the connecting cylinder 11 is provided with a second abutting portion 115 in a protruding manner, the first annular flange 31 is clamped between the first rotation stopping gasket 19 and the second abutting portion 115, and the first rotation stopping gasket 19 is clamped between the first annular flange 31 and the distal end screw cap 18. The second abutting portion 115 includes a first sub-segment 1151 and a second sub-segment 1153, which are fixedly connected, wherein the first sub-segment 1151 is protruded on an inner wall of the distal end of the through hole 111, and the second sub-segment 1153 and one end of the first sub-segment 1151, which is far away from the inner wall of the through hole 111, are fixedly connected and bent and extended toward the distal end outlet of the through hole 111, so that a distal end annular groove 1155 is formed at the distal end of the inner wall of the through hole 111 for accommodating the first annular flange 31.

The distal screw cap 18 includes a mounting portion 181 and a protrusion 183 formed by bending and extending a distal end of the mounting portion 181. The mounting portion 181 and the protrusion 183 together define a second annular groove 185. The distal end of the connecting cylinder 11 is fixed in the second annular groove 185, and the first rotation stop washer 19 is interposed between the boss 183 and the first annular flange 31. The outer wall of the far end of the connecting cylinder 11 is provided with external threads, the inner wall of the second annular groove 185 is provided with internal threads, the external threads of the far end of the connecting cylinder 11 are meshed with the internal threads of the second annular groove 185 of the far end screw cap 18, and the far end screw cap 18 can be detachably fixed at the far end of the connecting cylinder 11. It is understood that the protrusion 183 is not limited to be formed by bending and extending the distal end of the mounting portion 181, and the protrusion 183 may be protruded on the inner wall of the mounting portion 181.

When the internal thread of the distal screw cap 18 is tightly screwed with the external thread of the distal end of the connection cylinder 11, the first sub-segment 1151 of the second abutting portion 115 inside the distal screw cap 18 and the protrusion 183 of the distal screw cap 18 axially press the first rotation stop pad 19 and the first annular flange 31 of the flexible balloon 30. The first annular flange 31 and the first rotation stop washer 19 are deformed by compression to form an interference seal with the distal annular groove 1155 of the connector barrel 11 and the distal screw cap 18 to prevent blood from flowing out.

The first rotation preventing pad 19 is made of a smooth surface material, such as Polycarbonate (PC), Polytetrafluoroethylene (PTFE), and the like, the protrusion 183 of the distal end screw cap 18 is in smooth contact with the first rotation preventing pad 19, and during the rotation screwing process of the distal end screw cap 18, only axial extrusion occurs between the protrusion 183 and the first rotation preventing pad 19, so that radial rotation friction does not occur, and the first annular flange 31 of the flexible balloon 30 is prevented from being twisted or twisted due to the rotation of the protrusion 183, thereby reducing the possibility of damage to the first annular flange 31.

Referring again to fig. 21, the sealing member 10 further includes a vent 80 (e.g., a three-way valve) in communication with the connecting cylinder 11 for venting air.

Referring to fig. 28 and 29, the puncturing member 50 includes a puncturing body 51 and a connector 53 detachably connected to a proximal end of the puncturing body 51. Referring also to fig. 30, the second annular flange 33 at the distal end of the flexible balloon 30 is held in sealing engagement between the proximal end of the piercing body 51 and the connector 53.

The piercing body 51 is provided with an opening 511 in an axial direction, the opening 511 forms a part of the passage 101, and an inner wall of the opening 511 is capable of being in clearance fit with the medical instrument 200 after the medical instrument 200 is pushed into the passage 101, in other words, the inner wall of the opening 511 is in clearance fit with a part of the medical instrument 200 inserted into the passage 101. Puncture body 51 includes a tubular body 513 and a step portion 515 protruding from the outer wall of the proximal end of tubular body 513 and extending in the proximal direction. Step 515 and the outer wall of the proximal end of tube 513 together form a third annular groove 516, opening 511 is provided on tube 513 and extends along the axial direction of tube 513, and third annular groove 516 is provided around opening 511.

Referring to fig. 30, the second annular flange 33 of the flexible bladder 30 is sleeved outside the proximal end of the tube 513 and is received in the third annular groove 516. Since the outer diameter of the step 515 is larger than the outer diameter of the tubular body 513 so that the step 515 can abut the myocardial wall, the step 515 can cooperate with the constriction of the apex of the heart to position the piercing member 50 relative to the apex of the heart. Further, the step 515 may be glued or coated with a flexible material to make the step 515 more gentle to the myocardial wall to protect the heart tissue.

The connector 53 includes a connector body 531 and a protrusion 533 formed by bending and extending a proximal end of the connector body 531. The protrusion 533 together with the fitting body 531 form a fourth annular groove 535. A side of the fourth annular groove 535 adjacent to the joint main body 531 is internally threaded. An external thread is formed on the outer wall of the step part 515 far away from the tube body 513, and the internal thread of the joint 53 is meshed with the external thread of the step part 515, so that the joint 53 is detachably connected with the puncture main body 51.

The piercing member 50 further comprises a second rotation stop pad 55, the second rotation stop pad 55 is sleeved on the distal end of the flexible capsule 30, and the second rotation stop pad 55 is clamped between the second annular flange 33 and the protrusion 533 of the joint 53. When the joint 53 is screwed with the proximal end of the puncture body 51, the protrusion 533 of the joint 53 and the step 515 of the puncture body 51 axially press the second rotation prevention gasket 55 and the second annular flange 33 at the distal end of the flexible balloon 30, and after the second annular flange 33 and the second rotation prevention gasket 55 are pressed and deformed, an interference seal is formed between the third annular groove 516 of the puncture body 51 and the joint 53, so that blood is prevented from flowing out.

The second anti-rotation pad 55 has the same properties and functions as the first anti-rotation pad 19, and will not be described herein.

The inner diameter of the tube 513 may vary according to the outer diameter of the medical instrument 200, and the gap between the diameter of the opening 511 and the outer diameter of the medical instrument 200 is preferably in the range of [0.0,3.0] mm so that the tube 513 is in a clearance fit with the medical instrument 200 and the medical instrument 200 does not generate resistance when the medical instrument 200 passes through the tube 513. Meanwhile, the medical instrument 200 is inserted into the puncture main body 51, so that the medical instrument 200 is not in direct contact with the punctured cardiac muscle at the apex of the heart, and repeated relative motion and friction between the medical instrument 200 and the cardiac muscle are avoided, thereby reducing the damage to the cardiac muscle. When different instruments need to be replaced, the puncture main body 51 establishes a channel for entering the heart, so that the puncture frequency can be reduced, the myocardial injury is further reduced, the tightness of the apical pouch does not need to be readjusted, the operation steps can be reduced, and the operation time is saved. To ensure adequate support and good penetration of tubular body 513, tubular body 513 preferably has a wall thickness in the range of [0.4,0.7] mm. Preferably, the length of tube 513 should be greater than the ventricular wall thickness by [10.0, 20.0] mm, for example, the left ventricular wall thickness may be in the range of [9.0,12.0] mm, and the length of tube 513 may be in the range of [19.0,32.0] mm. The tubular body 513 may be straight or tapered, with the taper angle preferably ranging from 0.0, 5.0.

Referring to fig. 31 and 1, the puncture assisting device 100 may further include a dilator 70 movably disposed in the channel 101, and a distal end of the dilator 70 is exposed from a distal end of the puncture member 50. Dilator 70 is a hollow shaft, and the hollow inner diameter of dilator 70 preferably ranges from [0.9,2.6] mm to facilitate passage of a guidewire (not shown) therethrough. The proximal portion of dilator 70 is a constant diameter structure and may include a range of gauges, such as 24F, 27F, 30F, etc. The gap between the inner diameter of the tube 513 and the outer diameter of the dilator 70 is preferably [0.0,0.3] mm, and the outer diameter of the dilator 70 is substantially equal to the outer diameter of the sheath of the medical instrument 200, so as to ensure the smoothness and the sealing performance of the medical instrument 200 after entering the puncture assisting device 100. The distal end of the dilator 70 has a generally conical configuration, and to ensure good puncture and dilation properties of the conical configuration of the dilator 70, the axial length of the conical configuration of the distal end of the dilator 70 preferably ranges from [20,55] mm. To facilitate handling, the axial length of the dilator 70 is greater than the axial length from the proximal end of the sealing member 10 to the distal end of the penetrating member 50.

Prior to apical puncture, the dilator 70 is advanced into the axially disposed channel 101 of the puncture assist device 100. Because the sealing member 10 is an interference fit with the dilator 70, it is necessary to hold the sealing member 10 with one hand and the dilator 70 with the other hand during the pushing process, and manually push the dilator 70 through the puncture assist device 100 so that the distal end of the dilator 70 protrudes from the distal end of the puncture member 50. Referring to fig. 32, the tapered structure of the dilator 70 is punctured from the apex of the heart 300, with the distal end of the puncturing member 50 puncturing the ventricular wall at the apex of the heart 300 along with the distal end of the dilator 70. Referring to fig. 33 and 34, the step 515 at the proximal end of the puncturing element 50 is pressed against the outer surface of the apex of the heart 300, and the distal end of the puncturing element 50 is fixed to the apex of the heart by suturing and fastening the apex of the heart. Thereafter, the dilator 70 is withdrawn from the puncture assist device 100.

The medical instrument 200 is then inserted into the channel 101 of the puncture aid 100. In order to pass the medical instrument 200 through the sealing member 10, the medical instrument 200 is moved relative to the sealing member 10. To ensure the smooth threading process, the operator holds the sealing member 10 with one hand and pushes the medical instrument 200 through the channel 101 of the sealing member 10 with the other hand to overcome the interference fit resistance between the medical instrument 200 and the stop seal 15 (shown in fig. 4) and the resilient gasket 13 (shown in fig. 4). The medical instrument 200 is passed along the passageway 101 of the puncture aid 100, the medical instrument 200 is in interference fit with the passageway 101 of the sealing member 10 (as shown in fig. 4), the medical instrument 200 is passed through the flexible bladder 30 (as shown in fig. 5), and the medical instrument 200 is in clearance fit with the passageway 101 of the puncture member 50 (as shown in fig. 6). After the distal end of the medical instrument 200 to be treated is flush with the distal end of the puncture aid device 100 or the distal end of the medical instrument 200 is exposed to a position approximately [0.0,15.0] mm from the distal end of the puncture aid device 100 (i.e., an initial position), the relative movement of the medical instrument 200 and the sealing member 10 is stopped, as shown in fig. 35. It will be appreciated that the initial position may be set as desired.

The flexible balloon 30 is then used to adjust the position of the medical instrument 200. Specifically, since the distal end of the flexible balloon 30 is fixedly connected to the proximal end of the puncturing member 50, the puncturing member 50 penetrates through the apex of the heart 300 and is fixed relative to the apex of the heart by tightening of the apex of the heart, when the medical instrument 200 is pushed axially by an operator with a small driving force, the sealing member 10 interference-fitted with the medical instrument 200 moves synchronously in the axial direction, the distal end of the sealing member 10 transmits an axial force to the proximal end of the flexible balloon 30, and the flexible balloon 30 is compressed axially by the axial force, so that the axial position of the medical instrument 200 changes until the proper position is reached, as shown in fig. 36. This is accompanied by a decrease in the volume of the lumen of the flexible balloon 30 and an increase in the pressure in the lumen of the flexible balloon 30, wherein a portion of the blood in the lumen of the flexible balloon 30 is returned to the heart chamber due to the clearance fit between the lumen of the puncturing member 50 and the medical device 200, so that the pressure in the flexible balloon 30 is maintained constant again. When the medical instrument 200 is rotated, the medical instrument 200 and the sealing member 10 are rotated in synchronization, and the flexible bladder 30 is twisted and deformed to conform to the rotation direction of the medical instrument 200 and the sealing member 10, so that the radial position of the medical instrument 200 is changed. Of course, the medical device 200 and the sealing member 10 may be axially moved and rotated at the same time, and the flexible bladder 30 is axially compressed and torsionally deformed at the same time, so that the medical device 200 is adjusted to a proper position.

Fig. 37 shows the withdrawal of the medical instrument 200 from the puncture aid 100. At this time, one hand of the operator may grasp the sealing member 10 of the puncture aid 100, and the other hand may grasp the medical instrument 200 and withdraw it proximally, so that the medical instrument 200 and the sealing member 10 of the puncture aid 100 are relatively moved, thereby withdrawing the medical instrument 200, and then another medical instrument 200 may be replaced and introduced into the heart 300 through the puncture aid 100. That is, the sealing member 10 of the auxiliary puncture device 100 and the medical instrument 200 can always be moved synchronously when adjusting the position of the medical instrument 200, and the relative movement can only occur when the medical instrument 200 is inserted into the auxiliary puncture device 100 and removed from the auxiliary puncture device 100.

Referring to fig. 38 and 39, a puncture assisting device 100 according to a second embodiment of the present invention is substantially the same as the puncture assisting device 100 according to the first embodiment, except that the puncturing element 50 further includes a spiral needle 57 sleeved on the outer periphery of the puncturing body 51, a proximal end of the spiral needle 57 is fixedly connected to the proximal step portion 515 of the puncturing body 51, and the spiral needle 57 extends spirally toward the distal end of the puncturing body 51 along the axial direction of the puncturing body 51, i.e., the spiral needle 57 is added to the outer periphery of the distal end of the puncturing element 50, so as to fix the puncture assisting device 100 during the operation, and ensure the position stability of the puncture assisting device 100 relative to the living tissue (e.g., the heart). The distal end of the helical needle 57 ends between the proximal end of the piercing body 51 and the distal end of the piercing body 51, in other words, the axial length of the helical needle 57 is smaller than the axial length of the piercing body 51 for preventing the living tissue, such as the ventricular wall of the heart, from being penetrated by the helical needle 57, resulting in blood leakage.

In this embodiment, the spiral needle 57 is disposed around the outside of the tubular body 513 of the puncture body 51, and the proximal end of the spiral needle 57 is fixedly connected to the step portion 515 of the puncture body 51.

The spiral needle 57 may be rotated in a left or right direction. In the present embodiment, the spiral needle 57 is made of a stainless steel wire having a diameter of [1.0,3.0] mm. In order to secure the spiral needle 57 to the living tissue (for example, the myocardial tissue of the heart) with a sufficient anchoring force and prevent the living tissue from being pierced to cause blood leakage during the operation, the axial length of the spiral needle 57 is preferably in the range of [5.0,8.0] mm.

The distal end of the helical needle 57 is a sharp end to facilitate anchoring into living tissue, such as myocardial tissue of the heart. The proximal end of the spiral needle 57 and the step 515 of the puncture body 51 may be welded together during injection molding or may be bonded together after injection molding. It is to be understood that the connection manner of the screw needle 57 and the puncture body 51 is not limited.

Referring to fig. 40, taking the spiral needle 57 as a right-handed rotation as an example, after the puncturing member 51 of the puncture assisting device 100 comes into contact with the outer surface of the apex of the heart, the entire puncture assisting device 100 is rotated counterclockwise (from a near view to a far view), so that the spiral needle 57 penetrates into the myocardial tissue. When removal is desired after surgery, removal of the puncture aid 100 can be accomplished by rotating the puncture aid 100 clockwise about an axis (from a proximal to a distal viewing angle).

The transapical medical instrument 200 is usually operated with minimal trauma and without the heart beating, which affects the stability of the puncture aid and the position of the medical instrument 200 relative to the heart. In the second embodiment of the present application, the spiral needle 57 is added to the puncture member 50, and the puncture assisting device 100 can be fixed during the operation, and the positional stability of the puncture assisting device 100 and the medical instrument 200 with respect to the heart can be maintained.

The foregoing is merely a preferred embodiment of the present application and is not intended to limit the present application in any way. Although the present application has been described with reference to the preferred embodiments, it is not intended to limit the present application. Those skilled in the art can now make numerous possible variations and modifications to the disclosed embodiments, or modify equivalents thereof, without departing from the scope of the disclosed embodiments. Therefore, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present application are still within the protection scope of the technical solution of the present application.

Claims

1. A puncture auxiliary device is used for assisting a medical instrument to puncture tissues and is characterized by comprising a sealing part, a flexible bag body and a puncture part, wherein the near end of the flexible bag body is connected with the sealing part in a sealing way, the far end of the flexible bag body is connected with the puncture part in a sealing way, and the sealing part, the flexible bag body and the puncture part are axially communicated and form a channel; the medical instrument is movably inserted in the channel; the sealing part is in interference fit with the part of the medical instrument inserted in the channel, and the flexible capsule body and the puncture part are in clearance fit with the part of the medical instrument inserted in the channel.

2. The puncture aid of claim 1, wherein the sealing member comprises a connecting cylinder and a limit sealing element, the limit sealing element is accommodated in the connecting cylinder, the inner wall of the limit sealing element is in interference fit with the part of the medical instrument inserted in the channel, and the flexible balloon is in sealing connection with the distal end of the connecting cylinder.

3. The lancing aid of claim 2, wherein the sealing member further comprises a proximal screw cap removably attached to the proximal end of the connector barrel and extending partially into the connector barrel, wherein an outer wall of the retention seal abuts an inner wall of the proximal screw cap, and wherein an outer diameter of the retention seal increases from the proximal end to the distal end.

4. The puncture aid of claim 3, wherein the sealing member further comprises a resilient gasket disposed in the connector barrel, the stop seal member abuts between the proximal cap and the resilient gasket, the resilient gasket is provided with a slit, and the size of the slit is smaller than or equal to the maximum outer diameter of the medical instrument.

5. The lancing aid of claim 2, wherein the sealing member further comprises a distal screw cap removably attached to the distal end of the connector barrel, the proximal end of the flexible balloon being sealingly secured between the connector barrel and the distal screw cap.

6. A puncture assistance device according to claim 5, wherein the proximal end of said flexible bladder is connected to a first annular flange which is captively held between the distal end of said connector barrel and said distal screw cap.

7. The lancing aid of claim 6, wherein the sealing member further comprises a first anti-rotation gasket disposed about the proximal end of the flexible balloon, the first anti-rotation gasket being clamped between the first annular flange and the distal cap.

8. A puncture assistance device according to claim 2, wherein the interference between the inner wall of the stopper seal and the largest outer diameter of the medical instrument is in the range of [0.5,1.0] mm.

9. The lancing aid of claim 1, wherein the lancing element comprises a lancing body and a connector detachably connected to a proximal end of the lancing body, a distal end of the flexible balloon is sealingly fixed between the proximal end of the lancing body and the connector, the lancing body is axially provided with an opening, and an inner wall of the opening is in clearance fit with a portion of the medical instrument inserted in the channel.

10. A puncture assistance device as claimed in claim 9, wherein the distal end of said flexible bladder is connected to a second annular flange which is captively secured between the proximal end of said puncture body and said hub.

11. A puncture assistance device as claimed in claim 10, wherein said puncture member further comprises a second anti-rotation spacer disposed about said distal end of said flexible bladder, said second anti-rotation spacer being clamped between said second annular flange and said hub.

12. The puncture assist device of claim 9, wherein the puncture member further comprises a spiral needle disposed around the outer periphery of the puncture body, a proximal end of the spiral needle is fixedly connected to the proximal end of the puncture body, and the spiral needle extends spirally toward the distal end of the puncture body along the axial direction of the puncture body.

13. The puncture assist device of claim 12, wherein the distal end of the helical needle terminates between the proximal end of the puncture body and the distal end of the puncture body.

14. A puncture assistance device according to any one of claims 1 to 13, wherein said flexible bladder has an external shape that is generally olive, cylindrical, frustoconical or bellows.

15. A puncture assistance device according to any one of claims 1-13, wherein said flexible bladder is made of a flexible material having a young's modulus in the range of 0.02MPa to 0.4 MPa.

16. A puncture aid according to claim 15, wherein the flexible material is latex or nitrile rubber and the wall thickness of the flexible bladder is in the range of 0.2mm to 2 mm.

17. A puncture assistance device according to claim 14, wherein a support structure is provided within said flexible bladder, said flexible bladder encasing said support structure.

18. A puncture assistance device according to claim 17 wherein said support structure is in the form of a mesh, a helix or a loop.

19. The puncture assist device of claim 1, further comprising a dilator movably disposed within the channel, wherein a distal end of the dilator is exposed from a distal end of the puncture member.