title: Impact of the administration of probiotics on the incidence of ventilator-associated pneumonia: a meta-analysis of randomized controlled trials.
abstract: BACKGROUND
  Previous reviews showed no benefit for the administration of probiotics in critically ill patients, but they did not focus on ventilator-associated pneumonia.
  
  
  METHODS
  Meta-analysis of randomized controlled trials comparing probiotics and control in patients undergoing mechanical ventilation and reporting on incidence of ventilator-associated pneumonia.
  
  
  METHODS
  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.
  
  
  RESULTS
  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).
  
  
  CONCLUSIONS
  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.
authors.affiliation: Alfa Institute of Biomedical Sciences, Athens, Greece. isiempos@yahoo.com
authors.forename: Ilias I
authors.initials: II
authors.lastname: Siempos
authors.forename: Theodora K
authors.initials: TK
authors.lastname: Ntaidou
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Falagas
mesh_terms: D003422:Critical Care; D017052:Hospital Mortality; D006801:Humans; D053717:Pneumonia, Ventilator-Associated / Q000401:mortality / Q000517:prevention & control*; D019936:Probiotics / Q000008:administration & dosage*; D011552:Pseudomonas Infections / Q000401:mortality / Q000517:prevention & control*; D011550:Pseudomonas aeruginosa; D016032:Randomized Controlled Trials as Topic