Lack of Efficacy of Probiotics in Preventing Ventilator-Associated Pneumonia A Systematic Review and Meta-analysis of Randomized Controlled Trials

Background: Ventilator-associated pneumonia (VAP) remains a common hazardous complication in patients who are mechanically ventilated and is associated with increased morbidity and mortality. We undertook a systematic review and meta-analysis of randomized controlled trials to evaluate the efficacy and safety of probiotics for the prevention of VAP. Methods: The PubMed and EMBASE databases were searched to identify randomized controlled trials comparing probiotics with control for VAP in adult patients undergoing mechanical ventilation. The primary outcome was the incidence of VAP Secondary outcomes included ICU mortality, hospital mortality, urinary tract infection, catheter-related bloodstream infection, diarrhea, length of ICU stay, length of hospital stay, and duration of mechanical ventilation. Results: A total of 1,142 patients from seven trials were subjected to meta-analysis. Probiotics did not significantly decrease the incidence of VAP (OR, 0.82; 95% CI, 0.55-1.24; P = .35), with low heterogeneity among the studies (I-2 = 36.5%, P = .15). Probiotics also did not appear to significantly alter any of the other meta-analysis end points. Conclusions: The limited evidence suggests that probiotics show no beneficial effect in patients who are mechanically ventilated; thus, probiotics should not be recommended for routine clinical application. However, the results of this meta-analysis should be interpreted with caution because of the heterogeneity among study designs. Future studies should focus on the safety of probiotics. CHEST 2012; 142(4):859-868