Implant reduces risk of blood infection in dialysis patients

Johns Hopkins University graduate students have invented a device to reduce the risk of the infection, clotting and narrowing of blood vessels in patients who need dialysis because of kidney failure.

The so-called Hemova Port device, which has been designed to be implanted under the skin in a patient’s leg, would give a technician easy access to the patient’s bloodstream and could be opened and closed at the beginning and end of a dialysis procedure, helping to avoid infection and clotting. The device also includes a simple cleaning system, serving as yet another way to deter infections.

Currently, most dialysis access sites are in the arm or the heart. However, because the Hemova device is sutured to the leg’s femoral vein instead, it avoids the unnaturally high blood flows that cause vessel narrowing when dialysis machines are connected to veins and arteries in the arm. Hence the student inventors believe the Hemova Port’s leg connection should allow the site to remain in use for a significantly longer period of time.

The port received a $10,000 (£6,258) first prize for Johns Hopkins graduate students in the 2011 ASME Innovation Showcase. The competition, involving 10 teams, was conducted in Texas earlier this month at the annual meeting of the American Society of Mechanical Engineers.

The five biomedical engineering students on the team were enrolled in a one-year master’s degree programme in the university’s Center for Bioengineering Innovation and Design. Sherri Hall, Peter Li, Shishira Nagesh, Mary O’Grady and Thora Thorgilsdottir all recently graduated, and Li has formed a company to continue to test and develop the device.

With help from the Johns Hopkins Technology Transfer staff, the team has filed for three provisional patents covering the technology and has applied for a $50,000 grant to conduct animal testing.

Clinical trials involving human patients could begin as soon as 2013.

An illustration of a closeup view of the Hemova Port, connected below the skin in the patient’s leg to a femoral vein
An illustration of a close-up view of the Hemova Port, connected below the skin in the patient’s leg to a femoral vein