Objective: To document the effect of gingival and dental plaque antiseptic decontamination on the rate of nosocomial bacteremias and respiratory infections acquired in the intensive care unit (ICU).

Design: Prospective, multicenter, double-blind, placebo-controlled efficacy study.

Setting: Six ICUs: three in university hospitals and three in general hospitals.

Patients: A total of 228 nonedentulous patients requiring endotracheal intubation and mechanical ventilation, with an anticipated length of stay > or =5 days.

Interventions: Antiseptic decontamination of gingival and dental plaque with a 0.2% chlorhexidine gel or a placebo gel, three times a day, during the entire ICU stay.

Measurements and main results: Demographic and clinical characteristics, organ function data (Logistic Organ Dysfunction score), severity of condition (Simplified Acute Physiologic Score), and dental plaque status were assessed at baseline and until 28 days. Bacteriologic sampling of dental plaque and saliva was done every 5 days, and blood, tracheal aspirate, and bronchoalveolar lavage cultures were performed when appropriate. The primary efficacy end point was the incidence of bacteremia, bronchitis, and ventilator-associated pneumonia, expressed as a percentage and per 1000 ICU days. All baseline characteristics were similar between the treated and the placebo groups. The incidence of nosocomial infections was 17.5% (13.2 per 1000 ICU days) in the placebo group and 18.4% (13.3 per 1000 ICU days) in the plaque antiseptic decontamination group (not significant). No difference was observed in the incidence of ventilator-associated pneumonia per ventilator or intubation days, mortality, length of stay, and care loads (secondary end points). On day 10, the number of positive dental plaque cultures was significantly lower in the treated group (29% vs. 66%; p < .05). Highly resistant Pseudomonas, Acinetobacter, and Enterobacter species identified in late-onset ventilator-associated pneumonia and previously cultured from dental plaque were not eradicated by the antiseptic decontamination. No side effect was reported.

Conclusions: Gingival and dental plaque antiseptic decontamination significantly decreased the oropharyngeal colonization by aerobic pathogens in ventilated patients. However, its efficacy was insufficient to reduce the incidence of respiratory infections due to multiresistant bacteria.