Our database search identified ten RCTs (1,594 patients, 612 events) which satisfied the inclusion criteria. The meta-analysis assessing the effect of ARMs on in-hospital mortality showed a risk ratio (RR) of 0.84 [95 % confidence interval (CI) 0.74–0.95; I2 = 0 %], although the quality of evidence was considered to be low due to the risk of bias in the included trials and the indirectness of the evidence—that is, ARMs were usually conducted together with other ventilatory interventions which may affect the outcome of interest. There were no differences in the rates of barotrauma (RR 1.11; 95 % CI 0.78–1.57; I2 = 0 %) or need for rescue therapies (RR 0.76, 95 % CI 0.41–1.40; I2 = 56 %). Most trials found no difference between groups in terms of duration of mechanical ventilation and length of stay in the intensive care unit and hospital. The TSA showed that the available evidence for the effect of ARMs on in-hospital mortality is precise in the case of a type I error of 5 %, but it is not precise with a type I error of 1 %.
Although ARMs may decrease the mortality of patients with ARDS without increasing the risk for major adverse events, current evidence is not definitive. Large-scale ongoing trials addressing this question may provide data better applicable to clinical practice.