Subcutaneous vascular access devices

Tunneled dialysis catheters have played an important role in providing vascular access for hemodialysis for over 20 years, yet limitations associated with poor flow, thrombosis, and infections due to the transcutaneous nature of catheters have led to the development of alternative vascular access devices. This article reviews two historical devices-the Hemasite and the Bentley DiaTAP button-and provides an overview of two new fully subcutaneous vascular access devices-the LifeSite Hemodialysis Access System (Vasca, Inc., Tewksbury, MA) and the Dialock Hemodialysis System (Biolink Corp., Norwell, MA). These new subcutaneous devices differ significantly from currently available tunneled dialysis catheters in their design and method of use and may result in improved outcomes in hemodialysis patients. Indeed, initial clinical experiences with this new class of fully implanted access devices validate a subcutaneous approach to hemodialysis access and suggest that their high flow rates and low complication rates may make subcutaneous devices an attractive alternative to dialysis catheters for hemodialysis patients.