Two articles in this issue report results of 2 clinical trials that compared the effects of different ventilation strategies on mortality in patients with acute lung injury (ALI). In the first article, Meade and colleagues Article randomly assigned patients with ALI to either an established low-tidal-volume (6 mL/kg of predicted body weight) strategy or an experimental strategy combining low-tidal-volume ventilation and higher levels of positive end-expiratory pressure (PEEP) than the established strategy, and recruitment maneuvers to open collapsed lung tissue. The authors found that all-cause hospital mortality rates were similar in both patient groups. In an investigation of the optimal level of PEEP in patients with ALI, Mercat and colleagues Article randomly assigned patients to a minimal alveolar distension–moderate-PEEP strategy (5 to 9 cm H2O)
or to a high-PEEP (maximum plateau pressure, 28 to 30 cm H2O) lung-recruitment strategy. The authors found that the increased-recruitment PEEP strategy was not associated with significant improvements in 28-day or 60-day mortality compared with the moderate PEEP strategy.
In an editorial, Gattinoni and Caironi Article discuss the implications of the study outcomes for improved care of patients with ALI. In a second editorial, Chiche and Angus Article discuss study design challenges in the investigation of complex interventions in critically ill patients.