WO1998044983A1

WO1998044983A1 - Catheter insertion instrument

Info

Publication number: WO1998044983A1
Application number: PCT/CH1998/000122
Authority: WO
Inventors: Werner Fritz Dubach; Peter Dittes
Original assignee: Createchnic Ag
Priority date: 1997-04-10
Filing date: 1998-04-01
Publication date: 1998-10-15

Abstract

The invention relates to a catheter insertion instrument with a haemostasis valve, for inserting a catheter into a bloodstream. The haemostasis valve is accommodated in a two-part housing (G) and at least one sealing element (10) is provided between the two housing parts of the insertion instrument in such a way that it has a positive and/or non-positive fit, to seal the passage of the extended parts. The sealing element (10) comprises at least three slotted sealing discs (102) arranged one above the other, said sealing discs consisting of an elastic material, and at least one centering and supporting disc (101) placed above the sealing discs distally. A lubricant reservoir (103) is situated between each of the sealing discs (102) and the distal centering and supporting disc (101) has a central opening, the diameter of said opening tapering in a proximal direction.

Description

Kathe introductory tea

The present invention relates to a catheter introducer with a hamostasis valve for introducing a catheter into a bloodstream. Catheter introducer sets are used for the simple and quick repeated insertion and removal of catheters and other long rod-shaped objects into larger blood vessels. After the percutaneous puncture of the vessel, for example according to the Seidinger method, the proximal area of a working sheath guided by a guidewire is placed in the vessel lumen. This tubular hollow body not only forms a temporary access to the vessel, but also provides a communicating one It is therefore necessary to prevent blood from escaping at the distal end of the working scabbard, where there is normally a valve housing that uses a valve device to seal the channel formed by the working scabbard to the outside of catheters and other elongated medical instruments with different diameters into the working sheath and the subsequent movement of the same without liquid being able to pass through the valve device ter completion of the canal formed by the working divide can also be guaranteed. In addition, the entry of air must be prevented when importing, removing and moving the objects, otherwise air bubbles can form in the blood vessel, which can lead to life-threatening embolism.

EP-A-0 067 007 (ARGON MEDICAL Corp.) and EP-B-0 157 906 (E. WECK Inc.) describe a hemostasis valve which consists of a disc-shaped seal with a central opening and a thimble-like slotted diaphragm made of natural or synthetic rubber and has a lateral support rib.

From EP-B-0 198 962 (TERUMO) a valve of a medical device is known, the two diaphragms of which consist of elastomers such as natural or synthetic rubber. The disk-shaped diaphragms are provided with intersecting slits on both sides, which, however, do not penetrate the full height of the diaphragms.

EP-B-0 308 815 (CORDIS Corp.) describes a separating valve consisting of an elastomeric separating part which has a plurality of radial slots which penetrate the separating part in a helical manner. The separating part consists of silicone rubber with a hardness of 30-50 Shore A and is impregnated with 2 to 10 percent by weight of free silicone as a lubricant.

EP-B-0 316 096 (DIAG Corp.) describes an integral hamostasis valve seal which has both a sealing neck and sealing lips.

The hamostasis valve described in EP-A-0 369 314 (E. WECK Inc.) has two perforated and one slotted superposed valve disks, all of which consist of latex or silicone rubber.

From EP-B-0 370 720 (TERUMO) and EP-B-0 370 721 (TERUMO), integral, molded hamostatic valve bodies made of natural or synthetic rubber are known, which have at least two slotted or pierced cylindrical or dome-shaped elements lying on top of each other.

EP-B-0 416 467 (TERUMO) describes a medical valve which consists of a single disc made of natural or synthetic rubber and has two intersecting slots. Each slot has a different opening width on the two sides of the sealing washer. The opening width of the slots on one side are different. From EP-A-0 513 969 (DIAG Corp.) a further development of an integral hamostasis valve according to EP-B-0 316 096 (DIAG Corp.) is known, which in turn consists of natural or synthetic rubber.

EP-A-0 649 317 (UNISURGE Inc.) describes a one-part valve construction of an insertion set made of elastomeric material, which consists of a cylindrical wall and a perpendicular top wall with a central opening and a radially slotted bottom wall projecting downwards. The valve construction is made of hard 40 to 70 Shore A silicone rubber.

EP-A-0 692 278 describes a diaphragm of a hamostasis valve made of silicone rubber, the Shore A hardness of which is between 20 and 50. The elastomeric material from which the diaphragm is made is mixed with additives that can make up between 7 and 13 percent by weight of the diaphragm and are said to increase the sliding ability. Examples of such additives are titanium dioxide, PTFE, graphite and others.

All of these valve designs attempt to meet the requirements of a well-functioning hamostasis valve by using valves made of elastomers. Such cross-linked macromolecular materials can be stretched well, but are only slightly compressible. The previously known valves must therefore be stretched and deformed in at least two spatial directions in order to accommodate and seal catheters and other objects with different diameters. In order to immediately close the opening formed by the catheter again tightly after removal of the catheter, the elastomer material must return to its original shape. When passing an object through the valve construction, at least the force required to seal the slot must be overcome. Furthermore, the valve structure usually also has to be deformed and stretched. It has been shown that with many of the common valves either no satisfactory sealing of objects with small diameters (eg guidewires) is achieved, or the Frictional resistance when moving and moving objects with a large diameter (eg catheters are so high that the physician's sensory control is severely impaired. These conflicting requirements have so far hardly been met with simple disk-shaped diaphragms Described above, increasingly more complex designs for the valves and diaphragms have been developed, which not only require more complicated and therefore more expensive production processes, but are also more susceptible to malfunctions. However, when used in sensitive medical-surgical 3ereιch malfunctions and malfunctions are not tolerated.

It is therefore an object of the present invention to provide a hamostasis valve which is of the simplest possible construction, is easy to produce and yet functions properly.

This task is solved by a hamostasis valve according to claim 1.

Further design variants result from the dependent patent claims.

In the drawings, several examples of the subject matter of the invention are shown and explained in the following description. It shows:

1 shows a cross section through the valve-receiving area of the insertion set with the dilator fully inserted, the sealing element eingze_ch.net being omitted to the right of the center line L and left off from the center line;

FIG. 2 shows an enlarged view of the hamostasis valve with the surrounding housing, v, cbeι left of the middle line of the dilator removed and an inserted dilator is shown to the right of the center line;

3a shows a perspective view of the valve body with three valve disks of the same thickness as an exploded drawing;

FIG. 3b shows a perspective view of a further embodiment of the valve body;

FIG. 3c shows a perspective view of a further embodiment of the valve body;

4a shows a cross section through a valve body according to FIG. 3a;

4b shows a cross section through a valve body according to FIG. 3b; and

4c shows a cross section through a valve body according to FIG. 3c.

The two-part housing G shown in FIG. 1 consists of a housing body 1 and a housing cap 2. The housing body 1 of the catheter guide set essentially represents a hollow cylinder with a central opening, which tapers gradually from its distal 12 to its proximal 13 area and carries a side connector 11. In the interior of the housing body 1 there is a valve support surface 19 directly above the entry of the side channel 111 and perpendicular to the longitudinal axis L. In cooperation with a valve clamping surface 28 of an inner cap wall 22 of the housing cover 2, a sealing element 10 becomes clamped between the support surface 19 and the latter Valve clamping surface 28 held positively and non-positively. The sealing element 10 divides the interior of the housing G into a distal 21 and a proximal cavity 14. The proximal cavity 14 communicates with the cavity of the central channel Z, which is formed by a working sheath 5. The task of the sealing element 10 is to prevent the passage of liquid from the proximal 14 to the distal 21 cavity and the passage of air in the opposite direction. An inner side wall 15 of the proximal cavity 14 tapers conically downwards and thereby facilitates the insertion of elongated objects into the central channel Z of the working scabbard 5. This working scabbard 5 is an elongated flexible tube which is sealed at its distal end by a proximal wall 13 of the housing body 1 is enclosed and held non-positively. A conical grommet 4 made of stretchable material is inserted over the proximal end 13 of the housing body 1, the inner diameter of which in the unstretched state is smaller than the outer diameter of the proximal housing wall 13. A retaining rib 18 which extends in a ring on the outside of the proximal housing wall 13 engages when the grommet 4 is attached a circumferential recess 44 on the inner side of the bulb and thereby supports the frictional holding of the nozzle 4 on the housing body 1. In the proximal direction, the nozzle 4 projects beyond the housing body 1 and encloses the working sheath 5 with its proximal area 42 has a side fastening tab 41 which is perforated 43.

The bell-shaped housing cap 2 has the inner 22 and an outer wall 23. A plurality of radially resilient retaining fingers 24 extend in the distal extension of the inner housing wall 22, each of which has an inwardly projecting bead 25 and an upper stop surface which is perpendicular to the longitudinal axis L. 27 have. The circumferential, U-shaped annular groove in cross section, which is formed by the inner 22 and outer 23 wall of the cap 2, is dimensioned such that it can accommodate the distal end 12 of the housing body 1 when the cap 2 is placed on the housing body 1 becomes. An elongated dilator tube 31 of a dilator 3 can extend so far into the Working sheath 5 is inserted until a stop 34 of a dial end piece 33 abuts the stop surface 27. When the dilator 3 is fully inserted, the radially resilient holding fingers .24 hold the proximal part of the dilator end piece 33 with their beads 25.

The assembly of the catheter insertion unit is extremely simple, since all parts are snapped together and therefore no gluing, welding or screwing is necessary. Only the distal end of the working sheath 5 has to be firmly connected to the housing body 1 by gluing or welding. The other parts can of course still be glued, heat or ultrasonically welded. When installing the valve unit 10, the cylindrical sealing disks 102 and the support disk 101 lying above them, the outside diameter D _A of which. The inner diameter of the distal housing wall 12 is adjusted, as shown in FIG. When the cap 2 is plugged on, it is pushed over the distal region of the housing wall 12 until a retaining rib 26 running around the inside of the outer wall 26 into one on the outside of the distal one. Casing surrounding recess 16 snaps. The height of the inner cap wall 22 and the position of the recess 16 and the retaining rib 26 are matched to one another so that the valve clamping surface 28 of the inner cap wall 22 is in the axial direction at a distance from the valve support surface 19 when the cap 2 is inserted and snapped into place , which is at most the same size or less than the height H of the sealing element 10 used. The pressure on the support disk 131 and on the proximal sealing disk 102 ″ is passed on to the sealing disks 102, 102 ′ lying therebetween. The sealing disks compressed in this way expand laterally slightly and thereby bring about the gas- and liquid-impermeable sealing of the sealing element 10 relative to the housing body 1 and an additional sealing of the cut slots 10. As shown in Figures 3 and 4, the sealing element 10 consists of a distal perforated support and guide disk

101 made of medical steel or hard plastic as well as at least three sealing washers 102. The central opening 105 of the support and guide washer 101 tapers from distal to proximal. The conical shape of the opening 105 facilitates the insertion of elongated components, such as catheters and guidewires. Proximal to the support disk 101 are sealing disks 102 made of elastic plastic, which have a diametrically extending slot 104 which does not extend to the periphery. The slots 104 penetrate the sealing washers

102 in their full height and are cut and not punched. Extensive test series have shown that only sealing disks 102 with cut slots 104 are able to prevent liquids from passing through the slots 104 up to the required maximum liquid pressure of 40 kPa (300 mm Hg). Of course, further embodiments of the sealing element 10 according to the invention with a different number of slots or other slot shapes are possible.

The elastic plastics from which the sealing washers 102 are made have sufficient elasticity to hold the incisions 104 tight under physiological pressure conditions with the catheter removed and to act as a liquid and gas-tight barrier between the proximal cavity 14 and the distal cavity 21.

When the catheter is inserted, pulled out and moved, the sealing disks can only be deflected proximally in the axial direction, since the support disk 101 prevents the movement distally. If an object is pushed through the slots 104 of the sealing disks 102, the lips formed by the slots 104 are stretched and deflected in the axial direction proximally and outwards from the central axis L. For objects with small diameters (e.g. guidewires), the deflection is very small and the seal between the sealing element and the object is mainly due to the tension force of the sealing ben 102, which not only seals the slots 104, but also presses the sealing lips against the guidewire so strongly that there is a liquid-tight contact. Large-diameter objects stretch the opening formed by the slits 104 in the sealing disks 102 and are closely and fluid-tightly encased by the elastomer material. In order to enable the change from one state to another without any problems, the hysteresis loop of the elastomer material used, from which the sealing washers 102 are made, is ideally very narrow. This means that the load curve of the material differs only slightly from its relief curve.

Since the frictional resistance of the sealing washers 102 is often so high when moving large-diameter objects (eg catheters) that sensor control is severely impaired by the doctor, the sealing washers 102 are lubricated with silicone oil or another suitable lubricant before assembly impregnated. Due to the tightness of the slots 104 and the peripheral tight sealing of the sealing washers 102 against the inside of the housing wall 12, separate lubricant reservoirs 103 are formed between adjacent sealing washers 102. When an object is inserted through the slots 104 in the sealing washers 102, the friction between the object and the sealing washers 102 are reduced by the lubricant. A linear polymer from the group of polyorganosiloxanes or a mixture of different such polymers or paraffmol is used as the lubricant. In the previously known diaphragms which are impregnated with silicone oil, the lubricant is quickly rubbed off from the surfaces of the diaphragm which come into direct contact with the object being carried out, as a result of which the desired friction-reducing effect is quickly lost. This is not the case with the present invention, since the rubbed-off lubricant can be replaced by lubricant from the reservoirs 103 between the sealing washers 102. This keeps the frictional resistance low and constant when moving the object. The latter is crucial for sensory control of the cat- Interaction by the doctor and thus decisive for the acceptance of the product by the user.

In a preferred embodiment of the invention, the smallest inner diameter Di of the central through hole 105 is 3.6 mm and the height of the individual sealing disks 102 and 1 mm. However, the height of the sealing washers 102 can optionally be 0.5 to 3 mm. The smallest width Di of the central opening 105 is expediently chosen such that it is at least 0.2 mm larger than the diameter of the component to be carried out with the largest diameter.

In the advantageous exemplary embodiment of the present invention described above, the hardness of the sealing washers 102 made of elastomer material is between 30 and 80, but preferably 50 Shore A.

The dimensions of the support disk 101, the sealing washers 102, their slots 104 and the diameter of the working sleeve 5 are ideally matched to certain standardized catheter sizes and diameters. For this purpose, the nominal sizes according to DIN 13 273 can advantageously be used. The associated career number can be attached to the spout, for example. Individual, clearly visible parts of the introductory set can also be marked with the corresponding DIN color code.

In a further advantageous embodiment of the invention, which is shown in FIGS. 3c and 4c, the middle one of the three sealing disks is made of soft-elastic foam plastic material. This foam plastic sealing washer 106 is impregnated with a suitable lubricant and thus acts not only as a sealing element but also as a lubricant reservoir. Soft-elastic foam plastics with a density of 300 to 600 g / 1, preferably 450 g / 1 have the required material properties. In order to compress the microporous material with pore sizes from 10 to 1000 μm well and lm- To keep it clear, it is preferably open-pore. However, it can also be partially closed-pore.

It is obvious to a person skilled in the art that both the number, the thickness and the Shore A hardness of the sealing disks of a sealing element can be varied in the present invention.

The high demands placed on the function are met by the sealing elements according to the invention through the use of plastics with optimally coordinated material properties, the long-term avoidance of excessive frictional resistance through the use of lubricants from lubricant reservoirs and a simple and therefore inexpensive and reliable construction.

Claims

claims

1. Catheter introduction kit with a hamostasis valve for introducing a catheter into a bloodstream, the hamostasis valve being accommodated in a two-part housing (G) and with at least one sealing element (10) for the sealing passage between the two housing parts of the insertion kit with positive and / or non-positive connection g Elongated components are present, characterized in that the sealing element (10) consists of at least three slotted sealing disks (102) made of elastic material and one at least one distal centering and supporting disk (101), at least between the sealing disks (102). In each case there is a lubricant reservoir (103) and the distal centering and supporting disc (101) has a central opening (105), the diameter of which narrows from distal to proximal.

2. Catheter delivery kit according to claim 1, characterized in that at least one sealing washer (106) consists of soft-elastic foam plastic and at least one distal and at least one proximally arranged sealing washer (102) consists of an elastomer material, the foam plastic sealing washer (106) is soaked with lubricant, thus forming the lubricant reservoir.

3. Catheter delivery kit according to claim 1 or 2, characterized in that the sealing disks (102, 106) have at least one diametrically extending, not extending to the periphery αie sealing disks (102, 106) in their full height penetrating slot (104), the slot (104 ) is cut into the sealing material.

4. Catheter delivery kit according to claim 1 or 2, characterized in that the lubricant is a linear polymer from the group of polyorganosiloxanes or a mixture of different such polymers or paraffmol.

5. Catheter guiding set according to claim 1 or 2, characterized in that the elastomer material of the sealing discs (102) has a hardness of 30 to 80 Shore A, preferably a hardness of 50 Shore A.

6. Catheter guiding set according to claim 2, characterized in that the foam plastic material of the sealing disc (106) is preferably open-pore.

7. Catheter delivery kit according to claim 3, characterized in that the slots (104) of the disks (102, 106) run in a crossing arrangement, so that no two slots (104) of two disks (102, 106) come to lie congruently one above the other.

8. The catheter lead set according to claim 1, characterized in that the distal support disk (101) has a central lead-through opening (105) tapering towards the proximal end, the smallest diameter D _{τ of which is} at least 0.2 mm larger than the diameter of the elongated component to be carried out with the largest diameter .

9. catheter guiding set according to claim 1, characterized in that the support disk (101) consists of medical steel or hard plastic.

10. Catheter delivery kit according to claim 1 or 2, characterized in that the sealing discs (102, 106) have a thickness of 0.5 to 3 mm, preferably 1 mm.