This single-center randomized clinical trial set out to determine if non invasive mechanical ventilation (NIMV) reduced the incidence of intubation in severe chest trauma-related hypoxemia.  Patients with Pao2/Fio2<200 for >8h while receiving oxygen by high-flow mask within the first 48 h after thoracic trauma were included in the study. After 25 patients were enrolled in each group, the trial was prematurely stopped for efficacy because the intubation rate was much higher in controls than in NIMV patients. Length of hospital stay was shorter in NIMV patients (14 vs 21 days P = .001), but no differences were observed in survival or other secondary end points.