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.

What is claimed, is: 
     
       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.