End-Stage Renal Disease (ESRD) is a condition wherein the kidneys are incapable of removing toxins from the body. Over 660,000 Americans suffer from ESRD, with millions more in the early stages, known as chronic kidney disease . The only cure for ESRD is a kidney transplant, but the majority of patients receive dialysis every 2–3 days to filter their blood while on the transplant waitlist.
Efficient dialysis requires approximately 600 mL/min of flow, which is commonly achieved by directly connecting an artery to a vein in the arm. Such a shunt may be created with an intervening prosthetic graft or by suturing the vein to the artery directly (termed an arteriovenous fistula, or AVF).
Though accepted as the gold standard, AVF’s may take >6 weeks to heal and become useable, and 35–50% will never become accessible . Needle trauma to the AVF can weaken the vessel wall and produce aneurysms or hematomas, which leak blood, potentially causing infection or clotting off the AVF . These complications are costly: hemodialysis patients on average cost Medicare over $84,000 per year, and Medicare is the primary payer for more than 80% of nearly 500,000 dialysis patients in the U.S. . An improved dialysis access method is needed to address the clinical shortcomings and high costs associated with AVF’s.
A device has been developed to improve clinical outcomes and to reduce the failure rates associated with AVF’s. This device is a type of vascular access port which integrates with the external wall of the venous portion of the AVF, providing structural support to the vessel and preventing the types of trauma which lead to aneurysmal dilation or hematoma formation. The top and bottom sections are implanted independently within the patient’s soft tissue, allowing them to separate gradually as the AVF dilates during maturation. The result is a palpable and easy-to-access port which should improve AVF longevity (Figure 1).
Two unique design features were identified as key to the success of this vascular access port:
1. Type of membrane or seal
2. Proper tissue integration into the implant
This technical brief examines the selection of the proper membrane or seal on the port.