Oropharyngeal cleansing with 0.2% chlorhexidine for prevention of nosocomial pneumonia in critically ill patients: An open-label randomized trial with 0.01% potassium permanganate as control

Background: Oral cleansing with chlorhexidine decreases the incidence of nosocomial pneumonia in patients after cardiac surgery. However, evidence of its benefit in ICU patients is conflicting. Methods: Patients admitted to the ICU of an Indian tertiary care teaching hospital were randomized to twice-daily oropharyngeal cleansing with 0.2% chlorhexidine or 0.01% potassium permanganate (control) solution. Effects on the incidence of nosocomial pneumonia during ICU stay (primary outcome) and length of ICU stay and in-hospital mortality (secondary outcomes) were studied. Results: Five hundred twelve patients were randomized to either the chlorhexidine group (n = 250) or the control group (n = 262). Of the 471 subjects who completed the protocol, nosocomial pneumonia developed in 16 of 224 subjects (7.1%) in the chlorhexidine group and 19 of 247 subjects (7.7%) in the control group (p = 0.82; relative risk, 0.93; 95% confidence interval, 0.49 to 1.76); intention-to-treat analysis of 21 patients in whom the cleansing protocol was not followed revealed similar results. There was no significant difference between the study and control groups in the median day of development of pneumonia (5.0 days: interquartile range [IQR], 3.0 to 7.7 vs 5.0 days: IQR, 3.0 to 6.0, respectively), median ICU stay (5.0 days: IQR, 3.0 to 8.0 vs 6.0 days: IQR, 3.0 to 8.0, respectively), and mortality (34.8% vs 28.3%, respectively). On subgroup analysis, there was no significant difference in the primary and secondary outcomes in patients on mechanical ventilation, tracheal intubation, and coma (Glasgow coma scale ≤ 8). During the study period, nosocomial pneumonia developed in fewer subjects (35 of 471 subjects [7.4%]) than in the 3 months preceding and following the study (98 of 452 subjects [21.7%]; p < 0.001; relative risk, 0.34; 95% confidence interval, 0.24 to 0.49). Conclusions: Oropharyngeal cleansing with 0.2% chlorhexidine solution was not superior to oral cleansing with the control solution. However, the decreased incidence of nosocomial pneumonia during the study period suggests a possible benefit of meticulous oral hygiene in ICU patients.