Study objective and outcomes
The main objective of this trial was to evaluate, in a clinical setting, the effect of a 3-min preoxygenation in the recommended combination of ramp position associated with spontaneous breathing without additional continuous positive airway pressure (CPAP) or positive end-expiratory positive pressure (PEEP) (RP/ZEEP (spontaneous ventilation without positive pressure ventilation) group) to the reverse Trendelenburg position used in association with non-invasive positive pressure ventilation with pressure support of 8 cm H