Biocompatibility testing of a new silver-impregnated catheterin vivo

Abstract

The purpose of this investigation was to compare the local effects of polyurethane (Tecothane) 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 subcutaneously or percutaneously in the neck of 41 Sprague-Dawley rats and guided beneath the dorsal muscles into the peritoneal cavity. The incidence of bacterial abscesses along the implanted tubes was evaluated daily. After 90 days, or earlier if sepsis developed, 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 between silver-impregnated and non-impregnated tubes (5/6 with and 5/7 without silver). The only difference noted was in the group with percutaneously placed silicone tubes between those with and without silver. Abscesses only occurred in 2/4 animals in the silver group and in 5/5 animals in the control group. Histological examination showed no difference in either group between infectious and foreign body reactions. Silver particles in subcutaneous, muscle and peritoneal tissue could not be demonstrated.

The influence of Ag+, Zn2+ and Cu2+ exchanged zeolite on antimicrobial and long term in vitro stability of medical grade polyether polyurethane

“…The antimicrobial activity of silver is based on the release of silver ions which is an ion-exchange process [14,15]. Some studies have confirmed that the main drawback of silver is that during long term use if the released ions reach a certain concentration, silver could cause toxicity in both human and animal cells [16,17]. Impregnation of silver ions into the surface is a safer way to ensure antibacterial properties of the material since the silver concentration is lower in this case, and the release is governed by the diffusion of the ion from the top surface layers of the material.…”

“…Impregnation of silver ions into the surface is a safer way to ensure antibacterial properties of the material since the silver concentration is lower in this case, and the release is governed by the diffusion of the ion from the top surface layers of the material. For this application silver-sulfadiazine or other silver compounds are usually used [16][17][18]. Clinical studies have, however, proved that the antibacterial activity of silversulfadiazine impregnated catheters decreased rapidly.…”

Prevention of Biofilm Associated Infections and Degradation of Polymeric Materials Used in Biomedical Applications

“…By increasing the silver ion concentration the antimicrobial activity can be increased, however, a certain concentration in the human environment (10mg/L , (Schierholz et al, 1998)) is cytotoxic and may lead to argyria. The antimicrobial efficiency and the performance of antibiotics and silver treated catheters against CAI have been compared in several studies (Böswald et al, 1999, Lyu and Untereker, 2009, Paterson et al, 1999, Walder et al, 2002. The most commonly used antibiotics for treatment of the catheters are minocycline-rifampin, piperacillin, gentamicin, and ofloxacin.…”

“…The studies showed that use ofmonociclyne-rifampin, ofloxacim and chlorohexidine-silver-sulfadiazine resulted in the least number of CAI compared to the other agents. Silver sulfadiazine expressed a high degree of biocompatibility and applicability in human environment (Böswald et al, 1999, Paterson et al, 1999, however, monocycline-rifampin showed better antiseptic properties. The antibacterial mechanism of silver-sulfadiazine is not completely understood.…”

Paper material containing Ag cations immobilised in faujasite: synthesis, characterisation and antibacterial effects

“…The antimicrobial activity of silver has been confirmed on a wide range of organisms, including bacteria, viruses and fungi (Russel and Hugo 1994;Damm et al 2005). Simultaneously, concerns about the environmental impact of silver ions and particles have been growing in recent years, as expressed in literature (Böswald et al 1999;Venous 1999;Kim et al 2009;MarambioJones and Hoek 2010;Echegoyen and Nerín 2013;Cushen et al 2014). The content of silver in everyday goods, and thus also in packaging, is not currently regulated either in the European Union or in the United States of America (Seaton et al 2010;LangauerLewowicka and Pawlas 2015;Mackevica et al 2016).…”