Fig. 3From: Effect of reverse Trendelenburg position and positive pressure ventilation on safe non-hypoxic apnea period in obese, a randomized-control trialKaplan–Meier curves. The Kaplan–Meier curves illustrate the length of stay with greater SpO2 than 92% for both groups. Abbreviation: PPV: positive pressure ventilation, RP: ramp position, RT: reverse Trendelenburg position, ZEEP: zero end-expiratory pressure ventilationBack to article page