Modification of central venous catheter polymers to prevent in vitro microbial colonisation

The efficacy of an antimicrobial catheter for the prevention of bacterial colonisation was investigated. The catheter was hydrophilic coated (Hydrocath) and impregnated with the quaternary ammonium antimicrobial agent, benzalkonium chloride (BZC). Microbial colonisation of this central venous catheter was compared to that of polyurethane catheters with or without a hydrophilic coating. Adherence of five strains of Staphylococcus epidermidis to the three catheter types was determined with a microbial colonisation model. Adherence of three strains of Staphylococcus epidermidis to Hydrocath catheters was significantly reduced in comparison to polyurethane catheters (p < 0.01). BZC-impregnated Hydrocath catheters prevented bacterial colonisation of both the internal and external catheter surfaces (p < 0.01). These results were confirmed by scanning electron microscopy. The findings demonstrate that hydrophilic-coated Hydrocath catheters can inhibit bacterial adherence in vitro. Bacterial colonisation was further restricted by the addition of BZC to these coated catheters.