Effect of Different Inspired Oxygen Concentrations on Intraoperative Recruitment Outcomes in Patients Undergoing Abdominal Surgery

After the patient was admitted to the room, anesthesia induction was performed after pre-oxygenation for 3 minutes. Tracheal intubation was carried out once the medication had fully taken effect. After the surgery began, the inspired oxygen concentration was adjusted for each group. The first lung recruitment maneuver was performed 10 minutes later, and subsequent lung recruitment maneuvers were conducted when pulmonary compliance returned to baseline levels. This process was repeated, with all patients undergoing one final lung recruitment maneuver immediately at the end of the surgery.