Effects of Intraoperative Higher Versus Lower Positive End-Expiratory Pressure During One-Lung Ventilation for Thoracic Surgery on Postoperative Pulmonary Complications (PROTHOR): A Multicentre, International, Randomised, Controlled, Phase 3 Trial

In this international randomized trial involving 2,124 thoracic surgery patients requiring one-lung ventilation, the authors compared high positive end-expiratory pressure (PEEP) with recruitment maneuvers (10 cm H2O) to standard low PEEP without recruitment (5 cm H2O). Despite improved oxygenation and lower driving pressures with the high-PEEP strategy, there was no significant reduction in postoperative pulmonary complications (53.6 percent vs 56.4 percent). High PEEP caused substantially more intraoperative hypotension and arrhythmias, whereas hypoxemia occurred more often with low PEEP. Postoperative outcomes, including mortality and extrapulmonary complications, were similar between the groups. These findings indicate that routine intraoperative lung-expansion strategies do not improve pulmonary outcomes in this setting, and PEEP selection should instead be individualized based on real-time gas-exchange and hemodynamic status.