Infection is a key risk for patients with implanted medical devices
U.S. market for medical devices is the world’s largest and it is estimated at $100 billion. These devices save or drastically improve the quality of life of millions of people. However, common issues with even the most successful implanted devices arise from biocompatibility problems and risk of serious infections. The Center for Disease Control (CDC) reported that over 2 million people suffer from bacterial infections from inter-dwelling catheters annually and of these nearly 90,000 cases are fatal. Direct medical costs associated with such infections exceed $3 billion in US alone, and the CMS (Centers for Medicare and Medicaid Services) no longer reimburses hospitals for costs arising from certain HAIs (hospital-acquired infections). Bacterial biofilms that form on the surface of devices are highly resistant to both immune response and conventional antibiotics and thus present a daunting challenge. To overcome this problem, coating technologies have been developed and their market is estimated to reach $3.9 billion by 2014. Indwelling catheters with antimicrobial coatings are rapidly replacing conventional ones, especially in hospital settings. Development of new coatings that reduce both thrombosis and infection is urgently needed.
Technology that reduces infection associated with indwelling catheter
Researchers in the Chemistry Department at University of Michigan developed a device that can deliver nitric oxide (NO) in an electrochemically controlled manner and can be used in dual lumen catheter to prevent biofilm formation. Because NO has a very short half-life in blood, researchers have developed a method of generating NO from NO2- (nitrite) in situ using a copper electrode. This allows for long-term generation of NO (months) as nitrite can be stored at high concentrations in hydrogels and NO release can be controlled with application of voltage. Researchers have designed an NO release device that could be integrated in a dual lumen catheter and demonstrated that it is able to release NO in a controlled manner. Levels of NO generated by this approach were sufficient to reduce formation of microbial biofilms by 90 – 98 percent depending on bacterial species.
Applications and Advantages
- Infection prevention for indwelling catheters
- Infection prevention for other implanted medical devices
- Reduce risk of biofilm formation and infection
- Small anti-microbial agent reservoir
- Controlled release of anti-microbial agent
- Long-term release profile extends life of medical devices