Efficacy of β-agonists in prevention and treatment of acute lung injury: A meta-analysis of randomized controlled trials.

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) carry high mortality with limited drug therapies. β-agonists are potential candidates due to bronchodilatory and anti-inflammatory effects. This meta-analysis evaluated their efficacy and safety in ALI/ARDS. Randomized controlled trials (RCTs) of β-agonists in ALI/ARDS were identified through PubMed, Cochrane Library, Embase, Web of Science, and Scopus. Relative risks were used for dichotomous outcomes and mean differences for continuous outcomes. The Cochrane tool was used to evaluate bias, and Cochran's Q and the I2 statistics were used to evaluate heterogeneity. Six RCTs involving 1213 participants met the inclusion criteria. Beta-agonists significantly reduced ventilator-free days (mean difference - 1.98, 95% confidence interval [CI]: -3.21 to - 0.75, P = 0.002, I2 = 68%) and intensive care unit (ICU)-free days (-6.57, P = 0.001). They were associated with nonsignificant trend toward higher 28-day mortality (risk ratio: 1.23, P = 0.10) and a significant increase in 90-day mortality (risk ratio: 1.39, 95% CI: 1.03-1.89, P = 0.03). Sensitivity analysis confirmed robust results, showing increased risk of cardiac arrhythmias (risk ratio: 1.89, P = 0.0008) but no significant effect on organ failure-free days (-0.99, P = 0.31). In ARDS/ALI, β-agonists reduce ventilator-and ICU-free days but increase 90-day mortality and arrhythmia risk, with no impact on organ failure-free days. β-agonists are linked to long-term risks, such as increased mortality and arrhythmias, but they provide little clinical benefit in terms of reducing ventilator or intensive care unit time. They have no effect on the incidence of ARDS/ALI or outcomes of organ failure.