Hemodialysis and vascular access system

Abstract

A hemodialysis and vascular access system comprises a subcutaneous composite PTFE silastic arteriovenous fistula having an indwelling silastic venous end which is inserted percutaneously into a vein and a PTFE arterial end which is anastomosed to an artery. Access to a blood stream within the system is gained by direct puncture of needle(s) into a needle receiving site having a tubular passage within a metal or plastic frame and a silicone upper surface through which needle(s) are inserted. In an alternate embodiment of the invention, percutaneous access to a blood stream may be gained by placing needles directly into the system (i.e. into the PTFE arterial end). The invention also proposes an additional embodiment having an arterialized indwelling venous catheter where blood flows from an artery through a tube and a port into an arterial reservoir and is returned to a vein via a port and a venous outlet tube distinct and distant from the area where the blood from the artery enters the arterial reservoir. The site where blood is returned to the vein is not directly fixed to the venous wall but is free floating within the vein. This system provides a hemodialysis and venous access graft which has superior longevity and performance, is easier to implant and is much more user friendly.

Description

via a neck vein, i.e., a jugular vein, in an anatomical drawing, a ringed gortex tubing an outlet tube 53 of PTFE (ringed gortex) sewn to an artery 30 at 62 and coupled at its other end 63 62a to the needle access site 20. The site 20, see FIGS. 1-3, is joined by silastic tubing 64 68 to a second access site 20a which has an outlet silastic tube 65. The outlet tube 65 includes a plurality of perforations 66 at its outlet end which is positioned in the venous system 67 through a neck vein, i.e., a jugular vein 40. Either site 20 or 20a can be used for needle access.

FIG. 8 depicts an embodiment similar to that of FIG. 7 except that the coupling between the artery 30 and the first needle access site 20 is PTFE tube 69. The entry to the venous system 67 is via vein 40 which has silastic tubing 65 floated therein. 69a depicts PTFE joining parts 20 and 20a.

FIG. 9 illustrates a dual needle access site 80 which is coupled via ringed PTFE 53 to the subclavian artery 30 and floated into the venous system 67 via silastic tubing 65. The dual site 80 provides additional access through 25a, 25b in approximately the same area with tubing (not shown) extending through the dual site 80.

FIG. 10 depicts a variation of the invention at the venous end wherein the outlet of the port 20 comprises PTFE tubing 91 located within a silastic catheter 92. This design is appropriate if thrombosis is a problem in the outlet silastic portion of the shunt.

FIG. 11 discloses a quick coupler 45 joining the PTFE tubing 53 to the port 46 in the needle access site 20. A plastic or metal member 47 includes a portion 48 which engages the cylindrical tubing 10, an intermediate portion 49 extending perpendicularly outward and an end portion 43 tapered outwardly at an angle and including an inward projection 44. The projecting portion 44 of the member 47 engages a slot 54 in the port 46 firmly fixing the PTFE 10 therebetween. 45a is made of flexible material to allow a gentle curve in tubing as it exits/enters port.

FIG. 12 is an exploded view of a new port embodiment wherein the port 71 comprises a frame 72 having an inlet 73 and an outlet 74. The plastic or metal frame 75 includes a recessed reservoir 76 and end walls 78a and 78b. An upper member 85 having a recess 86 and downwardly projecting sides 87a and 87b fits within walls 77a and 77b. The member 45 rapidly couples the PTFE tubing 10 to site 71 with tubing 88 which fits over the inlet coupling 73 and the outlet coupling 74 with recessed portions 75a and 75b which engage tubing 88a and 88b and have couplers 89a and 89b which slide over the tubing 88a, 88b to engage the couplings 73 and 74.

FIG. 13 shows a typical dual port system showing holes 55 where ports 20 can be fixed in place.

FIG. 14 discloses a cuff 56 which is made of PTFE and sewn to a vein. No physiological/functional venues anastomosis is created as blood is returned at the end of the system distant from the cuff. The silastic end 12 may still be lined with PTFE.

The upper member 86 includes an oval silicone access site 90 with an outer housing 91 which includes an aperture 92 surrounds the silicone oval 90. This embodiment provides a quick assembly for a needle access site 71.

The Squitieri Hemodialysis/Vascular Access System avoids creation of a venous anastomosis, a revolutionary advancement, i.e. there is no site for neointimal hyperplasia at a venous anastomosis which accounts for the vast majority of PTFE arteriovenous graft failures (60-80%). This is accomplished by returning the blood into a larger vein via an indwelling venous catheter 42. The site of blood return to the venous system is not fixed to the vein wall where neointimal hyperplasia occurs with the standard PTFE bridge graft. This feature represents a tremendous advantage over the present grafts.

As a further advantage, the system is not stagnant and prone to thrombosis, i.e. constant flow through the new system avoids the problem of clotting inherent in indwelling dual lumen venous catheters which remain stagnant when not in use. It also avoids need to flush catheters with heplock thereby reducing nursing costs to maintain the catheter.

The Squitieri system avoids externalization of components which are prone to infection. Since dual lumen catheters exit the skin 14, they frequently lead to sepsis requiring catheter removal despite subcutaneous tunneling. This new access is entirely subcutaneous.

Very importantly the system proposed herein, avoids problems with the aspiration of blood from the venous system and “positional” placement through continuous flow. A frequent problem with dual lumen catheters is their inability to draw blood from the venous system due to clot and fibrinous debris ball-valving at the tip of a catheter. This new system receives blood directly from arterial inflow which ensures high flow rates needed for shorter, more efficient dialysis runs. It also avoids the frequent problem of the catheter tip “sucking” on the vein wall inhibiting flow to the dialysis machine and rendering the access ineffective.

The system avoids recirculation seen with dual lumen catheters resulting in more efficient and more cost effective dialysis.

The system avoids the need for temporary access with incorporation of “Needle Access Sites” 20. A-V fistulas and gortex grafts must “mature” for several weeks before use. This creates a huge strain on the patient as well as the doctor to achieve temporary access while waiting to use the permanent access. Temporary access is very prone to infection, malfunction and vein destruction. By placing sites 20 designed to receive needles 15 along the new access, the system may be used the day it is inserted.

The system avoids PTFE needle site damage with the incorporation of “Needle Access Sites” 20. Needle access directly into PTFE is presently uncontrolled and user dependent. Often, PTFE is lacerated by access needles. While this system may be accessed via the PTFE segment, the needle receiving sites are the preferred method. This leads to excessive bleeding which requires excessive pressure to halt the bleeding causing thrombosis of the graft. “Needle Access Sites” 20 on the Squitieri access system allow safe, quick, and easy entry into the system and avoid the complications inherent in placing needles directly into PTFE. It also avoids perigraft bleeding which will compress and thrombose the graft. By eliminating the long time needed to compress bleeding at the needle site, the system shortens dialysis runs.

The Squitieri system permits an easier, faster insertion technique. Only one anastomosis at the arterial end and a percutaneous placement of the venous end is required. A modification allows the system to be sutured to the vein wall while the system tubing is floated down stream from this site where the system enters the vein 40. This saves operating room time at thousands of dollars per hour. The technique is easier with faster replacement. It avoids difficult and time consuming revision of venous anastomosis required to repair venous outflow occluded by neointimal hyperplasia. If the system malfunctions, the silastic catheter end 65 slips out easily and the arterial PTFE end 53 is thrombectomized. New access sewn to the thrombectomized PTFE at the arterial end and the silastic venous end is replaced percutaneously via Seldinger technique or “open technique”.

The end result of the above advantages translates into superior patency rates and a decreased complication rate with this new system. Patients are spared the repeated painful hospitalizations for failed access as well as the emotional trauma associated with this difficult condition. The physicians are spared the dilemma of how to best treat these patients. This system will have a large impact on the current practice of vascular access in areas such as hemodialysis; plasmapheresis; chemotherapy; hyperalimentation; and chronic blood draws.

While the invention has been explained by a detailed description of certain specific embodiments, it is understood that various modifications and substitutions can be made in any of them within the scope of the appended claims which are intended also to include equivalents of such embodiments.

Claims

1. A Squitieri hemodialysis and vascular access system to shunt blood between a vein and an artery the system comprising:

(a) a first tube having a first end adapted to be connected to the artery and a second end;

(b) a second tube having a first end adapted to be connected to the vein and including a plurality of apertures extending therethrough and having a second end; and

(c) a needle access port having a frame including a conduit extending therethrough, said frame having an inlet connected to the second end of the first tube and an outlet connected to the second end of the second tube to provide a flow path for blood and a silicone member protruding from the frame to provide access for needles into the flow path, wherein the needle access port includes:

an outer frame member having an upper surface including an aperture extending therethrough and downwardly extending walls about its periphery having inlet and outlet apertures, wherein the upper surface includes a lower portion having a plurality of teeth;

a silicone member mounted within the frame having a surface engaged by the frame teeth and an upwardly protruding portion extending through the frame aperture; and

a second frame member having a transverse conduit extending between the inlet and outlet apertures, an upper surface having a plurality of teeth engaging the silicone member to effect a seal and wherein the second frame member is positioned within the walls of the first frame member.

2. The Squitieri hemodialysis and vascular access system of claim 1, wherein:

the first tube corresponds to PTFE tubing;

the second tube corresponds to silicone tubing; and

the protruding silicone member has an oval configuration.

3. The Squitieri hemodialysis and vascular access system of claim 1, wherein the first tube includes rings mounted thereabout to provide additional strength.

4. The Squitieri hemodialysis and vascular access system of claim 1 further comprising:

a second needle access port having an inlet and an outlet and silastic tubing coupling the inlet of the second needle access port to the outlet of the other needle access port and wherein the outlet of the second access port is coupled to the second end of the second tube.

5. The Squitieri hemodialysis and vascular access system of claim 1 wherein:

the first tube is provided as PTFE tubing which is adapted for attachment to the artery at one end and coupled to the access port at the other end; and

the second tube is provided as silicone tubing which is coupled to the needle access port at one end and is capable of being floated within the vein at the other end.

6. The Squitieri hemodialysis and vascular access system of claim 1, wherein:

the first tube is inserted within an outer silicone tubing at the inlet to the needle access port.

7. The Squitieri hemodialysis and vascular access system of claim 1, further including:

an adjustable band mounted about the first tube at the inlet to the needle access port to regulate blood flow.

8. The Squitieri hemodialysis and vascular access system of claim 4, wherein:

a second needle access port is mounted to the needle access port, said ports having a single frame and a conduit extending longitudinally therethrough to the outlet tubing.

9. A Squitieri hemodialysis and vascular access system to shunt blood between a vein and an artery, the system including:

(a) a first tube having a first end adapted to be connected to the artery;

(b) a second tube having a first end adapted to be connected to the vein and including a plurality of apertures extending therethrough and having a second end;

(c) a needle access port having a frame including a conduit extending therethrough, said frame having an inlet connected to the second end of the first tube and an outlet connected to the second end of the second tube to provide a flow path for blood and a silicone member protruding from the frame to provide access for needles into the flow path; and

a quick coupler for joining the first tube to the needle access port comprising a port member projecting outwardly from the frame inlet and having a circumferential slot extending thereabout, a cooperating member having an outer portion extending concentrically with the first tube and a portion extending outwardly therefrom and an outwardly sloped portion extending over the projecting port member and having an inner circumferential projection which engages the circumferential slot, and wherein the first tube extends over the port member to be engaged by the projecting portion of the cooperating member within the slot and a removable coupling which snaps over the cooperating member forcing it into a sealed engagement with the port member.

10. A Squitieri hemodialysis and vascular access system to shunt blood between a vein and an artery, the system including:

(a) a first tube having a first end adapted to be connected to the artery;

(b) a second tube having a first end adapted to be connected to the vein and including a plurality of apertures extending therethrough and having a second end; and

(c) a needle access port having a frame including a conduit extending therethrough, said frame having an inlet connected to the second end of the first tube and an outlet connected to the second end of the second tube to provide a flow path for blood and a silicone member protruding from the frame to provide access for needles into the flow path, wherein the needle access port comprises:

a first member having a base, walls extending upwardly therefrom to form an enclosed area, and outwardly extending couplings on opposite walls thereof at the inlet and outlet of said port;

a second member having a top including an upper aperture, downwardly extending side walls engaging the walls of the first member and having a conduit extending from the inlet to the outlet and a silicone member projecting form the upper aperture to provide needle access; and

a tube mounted over each coupling and a coupler which fits over each tube to seal the tubes to the couplings.

11. The Squitieri hemodialysis and vascular access system of claim 1, wherein:

the second tube is capable of being floated within a vein at the one end and the plurality of apertures in the second tube are distant from the site where the second tube is inserted into the vein, said second tube not being fixed to the vein wall.

12. A hemodialysis and vascular access system comprising:

an arterialized indwelling venous catheter having a graft section provided from a material which is biocompatible with an artery, has a nonthrombogenic characteristic, which is adapted for long term attachment to an artery and which includes a region for repeated needle access and a catheter section, with a first end of said graft section adapted to be coupled to an artery and a portion of the catheter section adapted to be inserted within a vein at an insertion site, said catheter section portion having at least one opening in an end thereof with at least one of the at least one openings in the catheter section portion adapted to be within the vein itself and wherein the at least one opening is distant from the insertion site such that blood flows from the artery through the catheter and is returned to the vein through the at least one opening while providing laminar blood flow between the artery and the vein.

13. The hemodialysis and vascular access system of claim 12, further comprising:

at least one needle having a first end coupled to a hemodialysis device and having a second end adapted for insertion directly into said graft section of the catheter to shunt the blood flow through the dialysis device.

14. The hemodialysis and vascular access system of claim 13 wherein said graft section is provided from a first tube and said catheter section is provided from a second tube comprising multiple layers and a first end of said first tube is coupled to a first end of said second tube.

15. The hemodialysis and vascular access system of claim 14 wherein said first and second tubes are adapted for percutaneously placement.

16. The hemodialysis and vascular access system of claim 14 wherein the end of said second tube which is coupled to the first tube includes an enlarged portion in which the first end of said first tube is disposed.

17. A method for providing hemodialysis and vascular access, comprising:

providing an indwelling venous catheter, having:

a graft section provided from a material which is biocompatible with an artery, has a nonthrombogenic characteristic, which is configured for long term attachment to an artery and which includes a first end of said graft section configured to be coupled to an artery and a region for repeated needle access; and

a catheter section, with a portion of the catheter section configured to be inserted within a vein at an insertion site, said catheter section portion having at least one opening in an end thereof with at least one of the at least one openings in the catheter section portion configured to be within the vein itself;

arterializing the indwelling venous catheter by attaching the graft section to an artery to form an arterialized indwelling venous catheter;

implanting the region for repeated needle access so that it is entirely subcutaneous;

inserting the catheter section into a vein through a side wall of the vein at the insertion site, such that the at least one opening is distant from the insertion site such that blood flows from the artery through the catheter section and is returned to the vein through the at least one opening while providing laminar blood flow between the artery and the vein; and

providing continuous fluid flow between the graft section and the catheter section at least when the region for repeated needle access is not being accessed.

18. The method for providing vascular access as in claim 17, wherein the catheter and graft sections are separable components at least prior to the step of providing continuous fluid flow.

19. The method for providing vascular access as in claim 18, further comprising connecting the catheter section and the graft section using a connector.

20. The method for providing vascular access as in claim 19, wherein the connector is a quick-couple connector.

21. The method for providing vascular access as in claim 17, wherein the at least one opening is free floating within the vein.

22. The method for providing vascular access as in claim 17, further comprising percutaneously accessing the vein.

23. The method for providing vascular access as in claim 22, wherein percutaneously accessing the vein comprises accessing the vein by Seldinger technique.

24. The method for providing vascular access as in claim 17, further comprising accessing the vein using an open cut down procedure.

25. The method for providing vascular access as in claim 24, further comprising placing a purse string suture about the insertion site of the vein.

26. The method for providing vascular access as in claim 17, further comprising floating said catheter section portion downstream from the insertion site of the vein.

27. The method for providing vascular access as in claim 17, wherein the vein is a neck vein.

28. The method for providing vascular access as in claim 27, wherein inserting the catheter section into the vein comprises inserting the catheter section into the neck vein and advancing the catheter section toward the right atrium.

29. The method for providing vascular access as in claim 17, further comprising subcutaneously tunneling an implantation site for at least a portion of the indwelling venous catheter.

30. The method for providing vascular access as in claim 17, wherein the catheter section is inserted into the vein before the graft section is arterialized to the artery.

31. The method for providing vascular access as in claim 30, further comprising attaching a free end of the graft section to a wall of the artery while the end of the catheter section having been inserted in the vein in such a way that the at least one opening in the end thereof is downstream of the site where the catheter section enters the vein.

32. The method for providing vascular access as in claim 17, wherein the catheter section is not fixed to the vein wall.

33. The method for providing vascular access as in claim 17, wherein the method avoids creating a venous anastomosis.

34. The method for providing vascular access as in claim 17, wherein the catheter section comprises a long, flexible plastic tube.

35. The method for providing vascular access as in claim 34, wherein the end is beveled.

36. The method for providing vascular access as in claim 17, comprising implanting a vascular access system comprising the catheter section and the graft section and implanting the system so that is entirely subcutaneous.

37. The method for providing vascular access as in claim 17, wherein the region for repeated needle access comprises needles receiving site(s) and comprises an internal chamber that is tubular in shape.

38. The method for providing vascular access as in claim 17, wherein the region for repeated needle access comprises self sealing material.

39. The method for providing vascular access as in claim 17, wherein the graft section comprises a PTFE section.

40. The method for providing vascular access as in claim 17, wherein the catheter section comprises a silicone section.

41. The method for providing vascular access as in claim 40, wherein the silicone section is lined with PTFE.

42. The method for providing vascular access as in claim 17, wherein the region for repeated needle access comprises multiple layers.

43. The method for providing vascular access as in claim 42, wherein the multiple layers comprise PTFE on the inside and silicone on the outside.

44. The method for providing vascular access as in claim 42, wherein the multiple layers comprise PTFE on the inside and silicone disposed outside of the PTFE.

45. The method for providing vascular access as in claim 17, wherein the material providing the graft section comprises a thrombus resistant coating.

46. The method for providing vascular access as in claim 45, wherein the thrombus resistant coating comprises heparin.

47. The method for providing vascular access as in claim 17, wherein a nonthrombenic characteristic is provided by continuous flow of blood through at least the graft section.

48. The method for providing vascular access as in claim 17, wherein the vein is a jugular vein.

49. The method for providing vascular access as in claim 17, wherein arterializing further comprises attaching the graft section to a side wall of an artery such that blood can flow from the artery into the graft and can flow in the artery downstream of the point of connection to the artery.

50. A hemodialysis and vascular access system to shunt blood between a vein and an artery, the system comprising:

(a) a first tube having a first end adapted to be connected to the artery and a second end;

(b) a second tube having a first end adapted to be connected to the vein and including a plurality of apertures extending therethrough and having a second end; and

(c) a needle access port configured to be subcutaneously implantable, the needle access port having a frame including a conduit extending therethrough, said frame having an inlet connected to the second end of the first tube and an outlet connected to the second end of the second tube to provide a flow path for blood and a silicone member protruding from the frame to provide access for needles into the flow path, wherein the needle access port includes:

an outer frame member having an upper surface including an aperture extending therethrough and downwardly extending walls about its periphery having inlet and outlet apertures, wherein the upper surface includes a lower portion having a plurality of teeth;

a silicone member mounted within the frame having a surface engaged by the frame teeth and an upwardly protruding portion extending through the frame aperture; and

a second frame member having a transverse conduit extending between the inlet and outlet apertures, an upper surface having a plurality of teeth engaging the silicone member to effect a seal and wherein the second frame member is positioned within the walls of the first frame member.

51. The hemodialysis and vascular access system of claim 50, wherein:

the first tube corresponds to PTFE tubing;

the second tube corresponds to silicone tubing; and

the protruding silicone member has an oval configuration.

52. The hemodialysis and vascular access system of claim 50, wherein the first tube includes rings mounted thereabout to provide additional strength.

53. The hemodialysis and vascular access system of claim 50, further comprising:

a second needle access port having an inlet and an outlet and silastic tubing coupling the inlet of the second needle access port to the outlet of the other needle access port and wherein the outlet of the second access port is coupled to the second end of the second tube.

54. The hemodialysis and vascular access system of claim 50, wherein:

the first tube is provided as PTFE tubing which is adapted for attachment to the artery at one end and coupled to the access port at the other end; and

the second tube is provided as silicone tubing which is coupled to the needle access port at one end and is capable of being floated within the vein at the other end.

55. The hemodialysis and vascular access system of claim 50, wherein:

the first tube is inserted within an outer silicone tubing at the inlet to the needle access port.

56. The hemodialysis and vascular access system of claim 50, further including:

an adjustable band mounted about the first tube at the inlet to the needle access port to regulate blood flow.

57. The hemodialysis and vascular access system of claim 53, wherein:

a second needle access port is mounted to the needle access port, said ports having a single frame and a conduit extending longitudinally therethrough to the outlet tubing.

58. A hemodialysis and vascular access system to shunt blood between a vein and an artery, the system including:

(a) a first tube having a first end adapted to be connected to the artery;

(b) a second tube having a first end adapted to be connected to the vein and including a plurality of apertures extending therethrough and having a second end;

(c) a needle access port configured to provide a subcutaneous connection between the first tube and the second tube, the needle access port having a frame including a conduit extending therethrough, said frame having an inlet connected to the second end of the first tube and an outlet connected to the second end of the second tube to provide a flow path for blood and a silicone member protruding from the frame to provide access for needles into the flow path; and

a quick coupler for joining the first tube to the needle access port comprising a port member projecting outwardly from the frame inlet and having a circumferential slot extending thereabout, a cooperating member having an outer portion extending concentrically with the first tube and a portion extending outwardly therefrom and an outwardly sloped portion extending over the projecting port member and having an inner circumferential projection which engages the circumferential slot, and wherein the first tube extends over the port member to be engaged by the projecting portion of the cooperating member within the slot and a removable coupling which snaps over the cooperating member forcing it into a sealed engagement with the port member.

59. A hemodialysis and vascular access system to shunt blood between a vein and an artery, the system including:

(a) a first tube having a first end adapted to be connected to the artery;

(b) a second tube having a first end adapted to be connected to the vein and including a plurality of apertures extending therethrough and having a second end; and

(c) a needle access port configured to be subcutaneously implantable, the needle access port having a frame including a conduit extending therethrough, said frame having an inlet connected to the second end of the first tube and an outlet connected to the second end of the second tube to provide a flow path for blood and a silicone member protruding from the frame to provide access for needles into the flow path, wherein the needle access port comprises:

a first member having a base, walls extending upwardly therefrom to form an enclosed area, and outwardly extending couplings on opposite walls thereof at the inlet and outlet of said port;

a second member having a top including an upper aperture, downwardly extending side walls engaging the walls of the first member and having a conduit extending from the inlet to the outlet and a silicone member projecting form the upper aperture to provide needle access; and

a tube mounted over each coupling and a coupler which fits over each tube to seal the tubes to the couplings.

60. The hemodialysis and vascular access system of claim 59, wherein:

the second tube is capable of being floated within a vein at the one end and the plurality of apertures in the second tube are distant from the site where the second tube is inserted into the vein, said second tube not being fixed to the vein wall.