Vascular access systems for hemodialysis

A hemodialysis and vascular access system comprises a subcutaneous composite PTFE Silastic arteriovenous fistula utilising an indwelling silastic venous end (12) which can be inserted percutaneously and a PTFE arterial end (10) which is anastomosed to an artery. Percutaneous access is then gained by direct puncture into a unique "needle receiving" site having a tubular passage (16) within a metal or plastic body (26) and a silicone upper surface (25) through which a needle is inserted to access the flow within the system. In an alternate embodiment without "needle sites", access may be gained by placing needles directly into the system i.e. the PTFE. The invention proposes an arterialized indwelling venous catheter where blood flows from an artery through the system and is returned to the venous system via an arrangement wherein the outflow openings are distinct and distant from the site where the system enters the vein. The site of blood returns to the venous system is not directly fixed to the venous wall but is free floating within the venous system- 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.