PERCUTANEOUS ACCESS DEVICE FOR PERITONEAL DIALYSIS

EXIT-SITE TUNNEL INFECTIONS LEADING TO PERITONITIS ARE SIGNIFICANT COMPLICATIONS OF CONTINUOUS AMBULATORY PERI- TONEAL DIALYSIS (CAPD). AN IMPORTANT FACTOR CONTRIBUTING TOSUCH DIFFICULTIES IS THE INABILITY TO PREVENT BACTERIAL INVASION OF THE SITE WHERE THE CATHETER GIVING ACCESS TO THEPERITONEAL CAVITY PASSES THROUGH THE SKIN. L.VAD'S NEW APPROACH TO THE DESIGN OF A PERCUTANEOUS ACCESS DEVICE (PAD)RELIABLY CREATES A BIOLOGICAL SEAL AT THE JUNCTION OF THE IMPLANT AND THE SURROUNDING TISSUES THAT IS IMPERVIOUS TO PASSAGE OF MICROORGANISMS. TWO PRINCIPAL DESIGN FEATURES MINIMIZE THE COMPLICATIONS OF INFECTION AND EXTRUSION: (1) THE TRANSCUTANEOUS PORTION, OR NECK, OF THE PAD IS RENDERED NANOPOROUS. FIBROBLASTS FROM THE RECIPIENT'S DERMIS ARE CULTIVATED IN VITRO ON THE PAD NECK. THESE CELLS EXTEND PROCESSES INTO THE NONOPORES, PROVIDING A STRONG INTERLOCK. AFTER PAD IMPLANTATION, THE COATED CELLS MERGE WITH THE HOSTDERMIS. (2) A LARGE VELOUR-COVERED FLANGE ATTACHED TO THE PAD NECK IS USED TO ISOLATE THE SKIN-PAD INTERFACE FROM APPLIED FORCES. THE GOAL OF THIS PROJECT IS TO QUALIFY A PAD DESIGN FOR CLINICAL USE IN PERITONEAL DIALYSIS (D-PAD) AND TO BRING IT TO COMMERCIAL SALE. TOWARD THIS END, THE SPECIFIC AIMS OF PHASE I INCLUDE: (1) MAKING DESIGN MODIFICATIONS FOR TRANSFER OF FLUID AND IMPLANTATION OF THE DEVICE IN THE PERITONEUM; (2) ADAPTING PREVIOUS CELL CULTIVATION TECHNIQUES FOR THE D-PAD; (3) EVALUATING THE PERFORMANCE OF THE PAD DESIGN IN ACUTE AND SHORT-TERM (3 MONTH) STUDIES; AND (4) EVOLVING THE EXPERIMENTAL DESIGN ANDPROTOCOLS FOR A COMPARATIVE LONG-TERM STUDY IN SWINE. IN PHASE II, THE EFFECTIVENESS OF THE D-PAD IN REDUCING EXIT SITE/TUNNEL INFECTION RATES WILL BE COMPARED WITH DESIGNS ALREADY COMMERCIALLY AVAILABLE.