Oral chlorhexidine to prevent nosocomial pneumonia in critically ill patients: a systematic review and meta-analysis

Introduction

This systematic review aims to evaluate evidence from randomised controlled trials (RCTs) for oral chlorhexidine in preventing nosocomial pneumonia in intubated mechanically ventilated critically ill adults. Use of oral chlorhexidine appeals since it should reduce bacterial aspiration from the orophayrnx. A number of RCTs have recently been published on this topic.

Methods

Search of Medline, Embase, Cochrane library, grey literature registers, conference proceedings and reference lists for RCTs comparing chlorhexidine with placebo or standard care for prevention of pneumonia in the critically ill. Outcomes: episode of nosocomial respiratory tract infection (RTI), mortality, duration of mechanical ventilation (MV) and length of ITU stay (ITU LOS). Review Manager 4.2 (Nordic Cochrane Centre) was used for data synthesis. Effect estimates (odds ratio for dichotomous and weighted mean difference for continuous data) were calculated using a random effects model.

Results

Fourteen studies were identified, three involving patients undergoing cardiac surgery (1,841 patients) and 11 involving patients in noncardiothoracic ITUs (1,497 patients; see Table 1). Five studies (including two cardiac studies) found a significant reduction in episodes of nosocomial RTI in the chlorhexidine-treated group versus placebo or standard care. Pooled data indicated a significant reduction in nosocomial RTI in the treatment group among all patients, and among cardiac and noncardiac sub-groups (odds ratio 0.57 (95% CI 0.42 to 0.77), 0.52 (0.37 to 0.75) and 0.6 (0.4 to 0.89), respectively). However, no significant differences in mortality, duration of mechanical ventilation or ITU stay were demonstrated. Significant heterogeneity (I2 statistic >40%) was detected for all outcomes except mortality.

Table 1 Effect estimates

Conclusions

Use of oral chlorhexidine is associated with reduction in nosocomial respiratory tract infection in intubated mechanically ventilated critically ill adults.