PETAL Network: ROSE- CCC for NHLBI Prevention and Early Treatment of Acute Lung Injury

To assess the efficacy and safety of early neuromuscular blockade in reducing mortality and morbidity in patients with moderate-severe ARDS in comparison to a control group with no routine early neuromuscular blockade. Hypothesis: Early neuromuscular blockade will improve mortality prior to discharge home before day 90, in patients with moderate-severe ARDS. Study Design: Multi-center, prospective, 2-arm, unblinded, randomized clinical trial of two management strategies of neuromuscular blockade (also called skeletal muscle relaxant and muscle relaxant).