Objective: To evaluate silver-impregnated (Oligon) central venous catheters and chlorhexidine-gluconate-impregnated sponges for reducing catheter-related colonization and infection, nonbacteremic or bacteremic.
Design: Multicenter, prospective, randomized, controlled study.
Setting: Five general intensive care units in Greece.
Patients: Intensive care unit patients requiring a multilumen central venous catheter between June 2006 and May 2008.
Interventions: Patients were randomly assigned to receive a standard catheter (standard group), a standard catheter plus chlorhexidine-gluconate-impregnated sponge (chlorhexidine-gluconate-impregnated sponge group), or an Oligon catheter (Oligon group). Catheter colonization was defined as a positive quantitative tip culture (≥10 colony-forming units/mL), catheter-related infection was defined by the previous criterion plus clinical evidence of sepsis, and bacteremia catheter-related infection as catheter-related infection plus a positive peripheral blood culture with the same micro-organism as in the catheter tip.
Measurements and main results: Data were obtained from 465 patients, 156 in the standard-group, 150 in the chlorhexidine-gluconate-impregnated sponge group, and 159 in the Oligon-group. Colonization occurred in 24 (15.4%) standard catheters, 21 (14%) in the chlorhexidine-gluconate-impregnated sponge group, and 25 (15.7%) in the Oligon catheters (p = .35) (20.9, 19.9, 21.8/1000 catheter-days, respectively). Catheter-related infections were recorded in nine (5.8%) standard catheters, six (4%) in the chlorhexidine-gluconate-impregnated sponge group, and seven (4.4%) in the Oligon catheters (p = .58) (7.8/1,000, 5.7/1,000, 6.1/1,000 catheter-days, respectively). No difference was observed between the chlorhexidine- gluconate-impregnated sponge group and the standard group regarding catheter colonization (hazard ratio 1.21; 95% confidence interval 0.56-2.61; p = .64) and catheter-related infections (hazard ratio 0.65; 95% confidence interval 0.23-1.85; p = .42). The Oligon catheter did not reduce colonization or catheter-related infections when compared with the standard catheter (colonization: hazard ratio 1.0; 95% confidence interval 0.46-2.21; p = .98; catheter-related infection: hazard ratio 0.72; 95% confidence interval 0.27-1.95; p = .52). Seven patients (1.5%, 2.09/1,000 catheter-days) presented bacteremic catheter-related infections. Central venous catheters inserted either in the internal jugular or the femoral vein had greater risk to be colonized than catheters inserted in the subclavian vein (internal jugular vs. subclavian: hazard ratio 3.29; 95% confidence interval 1.26-8.61; p = .01; femoral vs. subclavian: hazard ratio 3.36; 95% confidence interval 1.17-9.65; p = .02). Acinetobacter baumannii was the predominant pathogen (37.1% episodes of colonization, 36.4% catheter-related infections, 57.1% bacteremic catheter-related infections).
Conclusion: For short-term (median duration 7 days) central venous catheters in intensive care units with high prevalence of multiresistant Gram-negative bacteria, chlorhexidine-impregnated sponges and Oligon catheters as single preventive measures did not reduce catheter colonization or catheter-related infections. As a result of the limited amount of events, no conclusion could be reached regarding bacteremic catheter-related infections. The femoral site was the most frequently colonized insertion site in all types of catheters.