Risk factors associated with intravascular catheter infections in burned patients: a prospective, randomized study

A prospective, controlled study of 101 intravascular catheter sites was undertaken to determine the importance of tubing manipulation and skin contamination in the etiology of catheter infection in burned patients. Catheters in place for 3 days were randomized to have the tubing changed every 24 or 48 hours. Catheters were removed at 72 hours and the tips cultured by the semi-quantitative technique of Maki. Hubs were cultured (by swab culture) at times of tubing change and at the time of catheter removal. Skin cultures of the area surrounding the catheter were done at the time of insertion and removal. Catheter tip infection was defined as 15 or more colony forming units. Positive cultures were found in 25.7% of the cases, and were most often due to Pseudomonas species (33%) and coagulase-negative Staphylococcus (29%). Infections occurred in 35% of arterial catheters, 27% of central, and 12% of peripheral venous catheters. No benefit was observed from changing the administration tubing at 24 hours vs. 48 hours. Hub cultures were positive 30% of the time at 24 hours, 39% at 48 hours and 41% at 72 hours. Although the isolated organisms correlated with tip cultures, false positive rates varied from 8 to 62%. Discriminant analysis showed no relationship between catheter infection and burn size or day postburn; however, the incidence of catheter infection correlated inversely with the distance of the catheter insertion site from the burn wound (p = 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)