Effect Of Driving Pressure-Guided Positive End-Expiratory Pressure (Peep) Titration On Postoperative Lung Atelectasis In Adult Patients Undergoing Elective Major Abdominal Surgery: A Randomized Controlled Trial

Background: As respiratory system compliances are heterogenous, we hypothesized that individualized intraoperative positive end-expiratory pressure titration on the basis of lowest driving pressure can reduce postoperative atelectasis and improve intraoperative oxygenation and postoperative lung functions.Methods: Eighty-two adult patients undergoing major abdominal surgery were recruited in this randomized trial. In the titrated positive end-expiratory pressure group, positive end-expiratory pressure was titrated incrementally until lowest driving pressure was achieved, and the same procedure was repeated in every 2 hours. In the fixed positive end-expiratory pressure group, a positive end-expiratory pressure of 5 cmH(2)O was used throughout the surgery. The primary objective of this study was lung ultrasound score noted at the completion of surgery and 5 minutes after extubation at 12 lung areas bilaterally.Results: Mean (standard deviation) age of the recruited patients were 43.8 (17.3) years, and 50% of all patients (41 of 82) were women. Lung ultrasound aeration scores were significantly higher in the fixed positive end-expiratory pressure group both before and after extubation (median [interquartile range] 7 [5-8] vs 4 [2-6] before extubation and 8 [6-9] vs 5 [3-7] after extubation; P = .0004 and P = .0011, respectively). Incidence of postoperative pulmonary complications was significantly lower in the titrated positive end-expiratory pressure group (absolute risk difference [95% CI] 17.1% [32.5%-1.7%]; P = .034). The number of patients requiring postoperative supplemental oxygen therapy to maintain SpO(2) >95%, the requirement of intraoperative rescue therapy, and the duration of hospital stay were similar in both of the groups.Conclusion: Intraoperative titrated positive end-expiratory pressure reduced postoperative lung atelectasis in adult patients undergoing major abdominal surgery. Further large clinical trials are required to know its effect on postoperative pulmonary complications. (C) 2021 Elsevier Inc. All rights reserved.