Impact of the administration of probiotics on the incidence of ventilator-associated pneumonia: A meta-analysis of randomized controlled trials*

Abstract

Previous reviews showed no benefit for the administration of probiotics in critically ill patients, but they did not focus on ventilator-associated pneumonia. Meta-analysis of randomized controlled trials comparing probiotics and control in patients undergoing mechanical ventilation and reporting on incidence of ventilator-associated pneumonia. PubMed, Scopus, Current Contents, Cochrane Central Register of Controlled Trials, and reference lists were searched. Weighted mean differences, pooled odds ratios, and 95% confidence intervals were calculated, implementing both the Mantel-Haenszel fixed effect and the DerSimonian-Laird random effects model. Five randomized controlled trials were included. Administration of probiotics, compared with control, was beneficial in terms of incidence of ventilator-associated pneumonia (689 patients; fixed effect model: odds ratio, 0.61; 95% confidence interval, 0.41–0.91; random effects model: odds ratio, 0.55, 95% confidence interval, 0.31–0.98), length of intensive care unit stay (fixed effect model: weighted mean difference, –0.99 days; 95% confidence interval, –1.37–−0.61), and colonization of the respiratory tract with Pseudomonas aeruginosa (odds ratio, 0.35; 95% confidence interval, 0.13–0.93). However, no difference was revealed between comparators regarding intensive care unit mortality (odds ratio, 0.75; 95% confidence interval, 0.47–1.21), in-hospital mortality (odds ratio, 0.75; 95% confidence interval, 0.46–1.24), duration of mechanical ventilation (weighted mean difference, –0.01 days; 95% confidence interval, –0.31–−0.29), and diarrhea (odds ratio, 0.61; 95% confidence interval, 0.28–1.34). Administration of probiotics is associated with lower incidence of ventilator-associated pneumonia than control. Given the increasing antimicrobial resistance, this promising strategy deserves consideration in future studies, which should have active surveillance for probiotic-induced diseases.