Student-designed device could make dialysis safer and easier
By Ben Coxworth
June 29, 2011
There are approximately 1.5 million people worldwide who require regular hemodialysis treatments, due to the fact that their kidneys are no longer able to clean their blood. Clinicians generally reuse the same access point on each patient's body, for routing their bloodstream to the dialysis machine. Unfortunately, over time this can cause infections, blood clots or narrowing of the arteries at that access point. This can result in the need for a blood-vessel-opening procedure, or sometimes even in death. Now, however, a group of five biomedical engineering graduate students from Johns Hopkins University have created an implantable device, that could act as a safe, easy access point for dialysis.
Called the Hemova Port, the device would be implanted beneath the skin on the thigh, and sutured to the leg's femoral vein. Two access valves could be opened and closed from outside the skin, by a clinician using a syringe. The minimally-intrusive access would minimize the potential for clotting and infection, while a self-cleaning mechanism would further reduce the chances of infection.
Presently, dialysis access points tend to be near the heart or in the arm, where the blood flow is higher. This high blood flow, however, contributes to the narrowing of the blood vessels at those access points. Because the flow in the leg would be lower, narrowing wouldn't be as likely to occur.
Animal testing is already under way, with human trials possibly taking place within two years.
The Johns Hopkins students who designed and created the Hemova Port are Sherri Hall, Peter Li, Shishira Nagesh, Mary O'Grady and Thora Thorgilsdottir, all of whom have since graduated. The port, which won the US$10,000 first prize in the 2011 ASME [American Society of Mechanical Engineers] Innovation Showcase, will continue to be developed through a spinoff company run by Li.