New functional principle for a percutaneous lead

The idea of the new functional principle for a percutaneous lead is one of the award winners of the innovation competition 2000 in the field of medical engineering. It is awarded by the Bundesministerium für Bildung und Forschung (Federal Ministry of Education and Research). (Press release )

A percutaneous lead is designed for an enduring connection between the external environment and the inside of the body. Such an application is, for example, the ambulant peritoneal dialysis or an artificial cardiac assist system. These applications mostly require a tube penetrating the skin for the transport of fluid or air. All these skin penetrating tubes are endangered by inflammation, infection, marsupialization and extrusion. Usually the infections starts at the region, where the tube exits the body. The microbes attach to the tube and form a biofilm, which tends to expand on the surface of a foreign body and thus along the tube invades the body, generating a detachment of the tissue from the tube. The objective of this paper is to present a new device to solve this problem. The device is implanted subcutaneously and creates a sleeve, which surrounds the duct where it penetrates the skin. The sleeve imitates one prominent feature of natural percutaneous structures such as fingernails: Growth from the inside of the body to the outside. This is achieved by pumping liquid room temperature vulcanizing (RTV) silicone rubber from the outside of the body to the inside. The rubber is then extruded from an extrusion port. The aqueous environment within the body solidifies the liquid silicone, which then becomes silicone rubber. The liquid silicone rubber is continuously pumped into the extrusion port and thus the sleeve is continuously generated and pushed outwards. The device has been tested in vitro and functions as predicted.

A principle sketch of the percutaneous lead.

Percutaneous lead

Links and publications about the bionic percutaneous lead (in English and German):

http://www.ipem.ac.uk/docimages/1433.pdf (PDF-Datei; 328 KB)

http://www.charite.de/mediamed/00/46_00.htm

http://www.berlinews.de/archiv/1485.shtml

http://www.tpiweb.com/ics/cn_News/index.asp?mds=view&tid=33&nid=268