DEVELOPMENT OF A COMPLIANT HEMODIALYSIS ACCESS GRAFT

A COMPLIANT VASCULAR GRAFT FABRICATED FROM A UNIQUE POLYURETHANE MATERIAL HAS BEEN DEVELOPED AND TESTED AS A 4-MM-DIAMETER PROSTHESIS. THE MATERIAL USED IS UNIQUE BECAUSE ITS BULK AND SURFACE REQUIREMENTS HAVE BEEN SEPARATED AND DEVELOPED INDEPENDENTLY IN TWO DISTINCT MATERIALS. THE FINAL POLYMER POSSESSES OVERALL OPTIMIZED CHARACTERISTICS BY BLENDING OPTIMIZED SURFACE-ACTIVE COPOLYMERS INTO THE OPTIMIZED BULK MATERIAL. USING A PATENTED PROCESS FOR FABRICATION OF MULTILAYERED TUBING, 6-MM-DIAMETER VASCULAR GRAFTS WILL BE PRODUCED. THESE GRAFTS WILL BE TESTED BOTH IN VIVO AND IN VITRO. IN VITRO TESTING WILL INCLUDE COMPLIANCE, BURST STRENGTH, KINK RADIUS, ELONGATION, AND SUTURE PULLOUT STRENGTH. IN VIVO EVALUATION WILL BE ACCOMPLISHED USING 30-CM-LONG CONDUITS TO CREATE AN ARTERIOVENOUS (AV) FISTULA BETWEEN THEEXTERNAL CAROTID ARTERY AND IPSILATERAL EXTERNAL JUGULAR VEIN. DIRECT AV FISTULAS WILL ALSO BE CONSTRUCTED. POLYTETRAFLUOROETHYLENE (PTFE) CONDUITS WILL SERVE AS COMPARISONS. SOME CONDUITS WILL BE PUNCTURED 6 TIMES WEEKLY FOR 12 WEEKS. EXPLANTED GRAFTS WILL BE RESUBJECTED TO THE IN VITRO TEST PROTOCOL AS WELL AS STANDARD MICROSCOPIC EXAMINATION. IT IS EXPECTED THAT THESE GRAFTS WILL HEAL INTO THE VASCULARSYSTEM AND PROVE MORE DURABLE THAN PTFE CONDUITS AS WELL AS PROVIDING FEATURES SUCH AS SELF-SEALING, DECREASED THROMBUS FORMATION, AND LESS INTIMAL HYPERPLASIA.