415

Abstract

Introduction: The use of beta-2-agonist as an intervention for acute lung injury (ALI)/acute respiratorydistress syndrome (ARDS) patients is controversial. We aimed to perform a meta-analysis of the published randomized controlled trials (RCT), summarizing the current evidence, of use of beta-2-agonists on the outcomes (mortality andventilator free days) among patients with ALI/ARDS. Hypothesis: The use of beta-2-agonist in patients with ALI/ARDS does not improve mortality and ventilator duration. Methods: A comprehensive search of all the major databases; MEDLINE, EMBASE, CENTRAL, Ovid Cochrane Database of Systematic Reviews, Web of Science, and Scopus from their origin to March 2012 (any language, any population) was conducted. Controlled vocabulary supplemented with keywords was used to search for RCTs using beta-2-agonist for ALI. Two reviewers independently identified the eligible studies and extracted data. For additional information, the study authors were contacted. The effect size was measured by relative risk (RR) for mortality and mean difference for ventilator-free days, with 95% confidence interval (CI). Heterogeneity was tested with the Chi-squared test, I-square statistic was calculated to give an estimate of the degree of heterogeneity. Results: Out of 204 studies screened, three RCTs reporting mortality and ventilator-free days in ALI/ARDS patients treated with beta-2-agonist were identified, including 646 patients, of which 334 (51.7%) received beta-2-agonist. There was no significant decrease in 28-days and hospital mortality in the beta-2-agonist group, RR (95% CI) were 1.04 (0.50 - 2.16) and 1.22 (0.95-1.56) respectively. The ventilator-free days were significantly lower for the patients on beta-2-agonist (-2.20 days [-2.41,-1.99]). Significant heterogeneity was observed in 28-days mortality among the studies. Conclusions: In patients with ALI/ARDS, administration of beta-2-agonist did not decrease hospital or 28-days mortality. In addition, the patient’s on beta-2-agonists had to be ventilatedfor longer duration. The current evidence discourages the use of beta-2-agonist among ARDS patients.This meta-analysis is registered with PROSPERO, registration number: PROSPERO 2012:CRD42012002616