Impact of Individualized Positive End-Expiratory Pressure Guided by Driving Pressure on Postoperative Atelectasis Assessed by Lung Ultrasound in Laparoscopic Surgery Patients: A Randomized Controlled Trial

Purpose: Pulmonary atelectasis frequently develops during laparoscopic procedures under general anesthesia, often leading to postoperative pulmonary complications (PPCs). Given the connection between high driving pressure and these complications, this study employed ultrasonography to assess whether individualized positive end-expiratory pressure (PEEP) titration by minimum driving pressure reduces postoperative atelectasis. Patients and Methods: Adult patients with medium-to-high-risk PPCs who were scheduled for laparoscopic procedures were allocated to receive either a fixed PEEP of 5 cmH 2 O (Group C) or minimum driving pressure-guided individualized PEEP (Group D). The primary outcome was the lung ultrasound score (LUS) on postoperative day 1, and LUSs at other postoperative time points were also recorded. The secondary outcomes were occurrence of atelectasis evaluated by ultrasonography and occurrence of PPCs within 7 days postoperatively. Results: A total of 106 participants were assigned randomly, with 102 included in the final analysis. Individualized PEEP resulted in better intraoperative respiratory mechanics. Compared with Group C, Group D demonstrated a more substantial decrease in the LUS on postoperative day 1 (43– 6 vs 65– 8, P < 0.001), and this benefit persisted until postoperative day 3. Moreover, the occurrence of atelectasis evaluated by ultrasonography in Group D was considerably lower than that in Group C at 15 min after extubation (58.8% vs 80.4%, P = 0.018), and this advantage persisted until postoperative day 2. Compared with Group C, Group D experienced fewer PPCs within 7 days after surgery (13.7% vs 31.4%, P = 0.033), whereas other postoperative recovery indicators were not significantly different. Conclusion: In adult patients undergoing laparoscopic surgery, compared with a fixed PEEP of 5 cmH 2 O, the driving pressure-guided individualized PEEP strategy improved postoperative LUSs and reduced incidences of early postoperative atelectasis assessed by ultrasound. Furthermore, it was associated with fewer PPCs and lower rates of atelectasis in the first 7 postoperative days. Keywords: laparoscopy, postoperative complications, pulmonary atelectasis, positive-pressure respiration, driving pressure, ultrasonography