Role of noninvasive ventilation in acute lung injury/acute respiratory distress syndrome: a proportion meta-analysis.

BACKGROUND The role of noninvasive ventilation (NIV) in the management of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) is controversial. OBJECTIVE To assess the efficacy of NIV in patients with ALI/ARDS, using a meta-analytic technique. METHODS We searched the PubMed and Embase databases for relevant studies published between 1995 and 2009, and included studies that reported endotracheal intubation rate and/or mortality in patients with ALI/ARDS treated with NIV. We calculated the proportions and 95% CIs to assess the outcomes in the individual studies and pooled the results with a random effects model. RESULTS Our search yielded 13 eligible studies (540 patients). The intubation rate ranged from 30% to 86%, and the pooled intubation rate was 48% (95% CI 39-58%). The mortality rate ranged from 15% to 71%, and the pooled mortality rate was 35% (95% CI 26-45%). There was significant statistical heterogeneity (assessed via the I(2) test and Cochran Q statistic) in both intubation rate and mortality. There was no evidence of publication bias. CONCLUSIONS Our results suggest an almost 50% NIV failure rate in patients with ALI/ARDS, so NIV should be cautiously used in patients with ALI/ARDS. There is a need for a uniform NIV protocol for patients with ALI/ARDS.