Biocompatibility testing of a new silver-impregnated catheter in vivo

The purpose of this investigation nas to compare the local effects of polyu rethane (Tecothane(circle times)) and silicone tubes with or without silver impregnation in rats. Bacterial colonization or infection of the exit site and/or tunnel were documented and interpreted. All tubes were placed subcu taneously or percutaneously in the neck of 41 Sprague-Dawley rats and guide d beneath the dorsal muscles into the peritoneal cavity: The incidence of b acterial abscesses along the implanted tubes,vase, evaluated daily After 90 days, or earlier if sepsis de, eloped, the animals were killed painlessly and,various organs and tissues from the entry site and the catheter tunnel examined histologically; In the group,where polyurethane tubes were placed percutaneously, there was no difference in the frequency of abscesses betwe en silver-impregnated and non-impregnated tubes (5/6 with and 5/7 without s ilver), The only difference noted,vas in the group with percutaneously plac ed silicone tubes between those with and without silver. Abscesses only occ urred in 2/4 animals in the silver, er group and in 5/5 animals in the cont rol group. Histological examination showed no difference in either group be tween infectious and foreign body reactions. Silver, er particles in subcut aneous, muscle and peritoneal tissue could not be demonstrated.