Contamination of multi-use closed tracheal suction catheters: an in-vitro study.

The use of closed multi-use tracheal suction systems in ventilated patients is increasingly popular as it offers a number of potential physiological and microbiological advantages. As the use of these systems has been associated with an increased prevalence of tracheal colonization, effective self-cleaning mechanisms employed in these catheters are necessary. Using an in-vitro model we assessed the degree of catheter colonization in two multi-use catheter systems; Stericath and Trach-Care. Fifty of each catheter type were tested for colonization with five challenge organisms: Staphylococcus aureus (NCTC 6571); Pseudomonas aeruginosa (NCTC 10662); Haemophilus influenzae type b; S. epidermidis (slime producer); and S. epidermidis (slime non-producer). All five challenge strains had colonized both catheter types after 24 h and all 100 catheter tips were colonized. The extent and density of colonization was variable and interspecies variation in the pattern of catheter colonization was observed. The mean colonized lengths of Stericath catheters was 10.9 +/- 1.4 cm and of Trach-Care 2.7 +/- 1.3 cm (P < 0.0001).