Effect of lung recruitment and titrated positive end-expiratory pressure (PEEP) versus low PEEP on patients with moderate-severe acute respiratory distress syndrome: a systematic review and meta-analysis of randomized controlled trials

Background: Setting a positive end-expiratory pressure (PEEP) on patients with acute respiratory distress syndrome (ARDS) receiving mechanical ventilation has been an issue of great contention. Therefore, we aimed to determine effects of lung recruitment maneuver (RM) and titrated PEEP versus low PEEP on adult patients with moderate-severe ARDS. Methods: Data sources and study selection proceeded as follows: PubMed, Ovid, EBSCO, and Cochrane Library databases were searched from 2003 to May 2018. Original clinical randomized controlled trials which met the eligibility criteria were included. To compare the prognosis between the titrated PEEP and low PEEP groups on patients with moderate-severe ARDS (PaO2/FiO(2) < 200 mmHg). Heterogeneity was quantified through the I-2 statistic. Egger's test and funnel plots were used to assess publication bias. Results: No difference was found in 28-day mortality and ICU mortality (OR = 0.97, 95% CI (0.61-1.52), p = 0.88; OR = 1.14, 95% CI (0.91-1.43), p = 0.26, respectively). Only ventilator-free days, length of stay in the ICU, length of stay in hospital, and incidence of barotrauma could be systematically reviewed owing to bias and extensive heterogeneity. Conclusion: No difference was observed in the RM between the titrated PEEP and the low PEEP in 28-day mortality and ICU mortality on patients with moderate-severe ARDS.