SBIR-STTR Award

Exit-site tunnel infections leading to peritonitis are significant complications of continuous ambulatory peritoneal dialysis (CAPD). An important factor contributing to such difficulties is the inability to prevent bacterial invasion of the site where the catheter giving access to the peritoneal 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 nanopores, providing a strong interlock. After PAD implantation, the coated cells merge with the host dermis. (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 (DPAD) 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 and protocols for a comparative long-term study in swine.In Phase II, the effectiveness of the DPAD in reducing exit site/tunnel infection rates will be compared with designs already commercially available.National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Exit-site/tunnel infections leading to peritonitis are significant complications of continuous ambulatory peritoneal dialysis. An important factor in such complications is the bacterial invasion of the site where the catheter giving access to the peritoneal cavity passes through the skin. This new approach to the design of a percutaneous access device (PAD) creates a reliably impervious biological seal at the junction of the implant and the surrounding tissues.Two principal design features minimize infection and extrusion. First, 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 nanopores, providing a strong interlock. After PAD implantation, the coated cells merge with the host dermis. Second, a large velour-covered flange attached to the PAD neck is used to isolate the skin-PAD interface from applied forces.In Phase I, a PAD was developed having provision for dialysate transfer, the cell cultivation technique was adapted to the new D-PAD, and the device was successfully tested in swine. In Phase II, long-term animal experiments will be performed to quantify the failure-free life expectancy of the D-PAD. Exit-site/tunnel infection in the D-PAD will be compared with infection in a standard commercial catheter.

Anticipated Results:
PAD's can be used for peritoneal dialysis and other therapies, such as parenteral nutrition and orthopedic implants requiring a permanent port in the skin.National Institute Of Diabetes And Digestive And Kidney Diseases (NIDDK)