Important aspects of the colonization of central venous catheter

This study comprises five different kind of venous central catheters, 103 in total, made of Polyurethane Tecoflex, Polyurethane Vialon, PTFE and PVC, and the influence of their raw material on the microbial colonization. Patients age and sex, besides their clinical conditions, were taken into account, and neither considered as a sample vicious, nor associated with colonization. When the tips of the catheters were asseptically inoculated in Tryptic Soy Broth and Tioglicolate, colonization was detected in 15.5% of the catheters. Coagulase negative Staphylococcus, some of which with biofilm, were the predominant organisms found, although some bacillus have also been detected: Enterobacter aerogenes, Hafnia alvei, Pseudomonas cepacia, Xanthomonas maltophilia and Aeromonas sobria. It was not possible to notice any association between the colonization of the catheters and their raw material, probably due to the influence of a previous contact and linking with blood components. This contact causes a thin coating on the surface of the cathether, which makes all the catheters similar in respect of the attachment of a bacterial cell. So, the colonization depends on the virulence of the organism, much more then on the nature of the catheter.