This study of 2,500 adults receiving mechanical ventilation randomized 1/3 were assigned to an exigent saturation target pf 90%, 1/3 to a target of 94%, and 1/3 to a target of 98%. The median number of ventilator-free days was 20, 21, and 21 for the three target groups, respectively. In-hospital death by day 28 was 34.8%, 34.0%, and 33.2% for the three groups, respectively.