Optimal Level of PEEP in Protective One-lung Ventilation

Protective ventilation strategy has been widely applied in the field of thoracic surgery requiring one-lung ventilation to reduce postoperative pulmonary complications. Low tidal volume, positive end-expiratory pressure (PEEP), and intermittent recruitment maneuver are key components of protective ventilation strategy. Recent evidence suggests that a tidal volume of 4-5 ml/kg should be applied during protective one-lung ventilation. However, optimal level of PEEP is still unclear. This study aims to investigate optimal level of PEEP to minimize postoperative atelectasis by comparing modified lung ultrasound score in patients applied protective one-lung ventilation using PEEP of 3, 6, or 9 cm of water during thoracic surgery.