In vitro evaluation of the antimicrobial efficacy and biocompatibility of a silver-coated central venous catheter.

Central venous catheter infection presents an important problem in modern medicine, leading sometimes to a life-threatening situation for the patient as well as contributing to prolonged hospital stay and to an increase in costs. We have evaluated the in vitro biocompatibility and antimicrobial activity of a silver-coated polyurethane catheter designed for use as a colonization-resistant, antiinfective catheter. Due to a comparatively low silver release, the catheter performed well in cell toxicity and blood compatibility tests as well as in acute toxicity tests done with mice. The antimicrobial activity was tested in stationary and dynamic bacterial adherence experiments using S. epidermidis, E. coli and P. aeruginosa as test strains. The silver-coated polyurethane catheter showed good ability to prevent microbial colonization of the catheter surface. Currently a clinical trial of the silver-coated catheter is under investigation.

Prevention of catheter-related infections by silver coated central venous catheters in oncological patients.

Catheter-related infection (CRI) is a serious complication of central venous catheterization. We have investigated the efficacy of a silver-coated polyurethane catheter (Pellethane, Fresenius AG, Germany) in preventing CRI in oncological patients receiving chemotherapy in a phase II study. From November 1992 through April 1994, 266 patients were assigned to receive single lumen catheters, either standard uncoated catheters (UC, n = 113) or silver-coated ones (SC, n = 120). Catheters were inserted into the internal jugular vein after institutional approval and informed consent. Duration of catheterization (UC vs. SC = 13.3 vs. 12.7 days) and leukopenia (< 1.0 x 10(9) WBC/l; 4.3 vs. 3.6 days) were similar in both groups demonstrating a comparable risk for infections. Skin reactions at the catheter entry site were recorded daily. CRI and colonization rates were studied by semiquantitatively culturing intradermal and intravascular segments. CRI were confirmed by blood cultures obtained via catheter and from peripheral veins in cases of suspected sepsis or at the end of catheterization. No adverse effects from the silver-coated catheter could be observed. The bacteriological results showed that SC were colonized (> 15 CFU) in 45.1% and UC in 44.2%. CRI developed in 21.2% of the UC patients but only in 10.2% of the SC patients (p = 0.011). We conclude that this new silver-coated central venous catheter is biocompatible and effective in reducing the incidence of catheter-related infections in oncological patients.