How Can We Achieve Infection‐Resistant Percutaneous Energy Transfer?

Abstract

Clinical records show ever increasing functional times of rotary blood pumps implanted in patients. With longer functional time, the problem of driveline infection is becoming more urgent. No material or scaffold has been found, which allows a permanent and stable ingrowth of skin cells that would prevent (pathogenic) germs entering the body. Usually, the epithelial cells die at the exit site and new cells form a sulcus around the driveline, which grows deeper and finally becomes infected. The purpose of this project is to present a solution to this problem by elaborating a new mechanism, the active skin-penetrating device. The device is composed of a tube with a 5-mm diameter, a protective sleeve that surrounds the catheter exit site, and an active traction device. The protective sleeve is made of thin polyurethane covered with polyethylenterephtalat (PET, i.e. Dacron) fibers to permit the attachment of keratinocytes, similar to the standard driveline. The active traction device exerts a constant pull on the protective sleeve. The ingrown keratinocytes slowly give way and the protective sleeve gradually moves out of the body at a rate of a few millimeters per week. Meanwhile, the keratinocytes transform into horny cells and are then shed as in natural skin. Therefore, the formation of a sulcus is avoided, and the protective sleeve remains infection-free. In a first proof of the concept, four of the new devices and 10 control devices were implanted in goats. The devices remained infection-free for a period of 420 days, whereas four of the 10 control devices became infected. On the basis of these experiments, the active skin-penetrating device has been further developed and is being tested again in goats in a refined version. The results so far indicate that with the active-skin penetrating device an infection-resistant percutaneous energy transfer can be achieved for a prolonged period of time.