Effects of heparin and chlorbutol on bacterial colonisation of intravascular cannulae in an in vitro model.

An in vitro model was used to study the effects of heparinised saline, with or without the preservative chlorbutol, on the colonisation of intravascular cannulae. Chlorbutol significantly reduced cannula colonisation by Staphylococcus epidermidis. Flushing colonised cannulae with heparinised saline plus chlorbutol significantly reduced the number of organisms adhering to the inner surface of cannulae, when compared with the use of heparinised saline without preservative. Chlorbutol-preserved heparinised saline may not only maintain cannula patency by the prevention of thrombus formation, but may also reduce the incidence of bacterial colonisation of cannulae in vivo.