Driving pressure guided ventilation versus conventional lung protective strategy in morbid obese patients undergoing laparoscopic bariatric surgery: a prospective randomized controlled study.

BACKGROUND: Mechanical ventilation in bariatric surgery presents unique challenges, requiring strategies that minimize intraoperative atelectasis, maintain adequate oxygenation, and lower the risk of postoperative pulmonary complications. The present study compared driving pressure-guided ventilation with conventional lung-protective ventilation in morbidly obese patients undergoing laparoscopic bariatric surgery. METHODS: Sixty patients with a body mass index (BMI) of 40-50 kg/m², scheduled for laparoscopic bariatric surgery, were randomized according to intraoperative ventilation strategy into two groups: Group I (n = 30) received the conventional lung-protective strategy, and Group II (n = 30) received the driving pressure-guided ventilation strategy. After induction of pneumoperitoneum, a standardized lung recruitment maneuver was performed, after which ventilation strategies were applied according to group allocation: in Group I, positive end-expiratory pressure (PEEP) was maintained at 5 cmH₂O throughout surgery, whereas in Group II, PEEP was individualized to achieve the lowest driving pressure (DP). RESULTS: The PaO₂/FiO₂ ratio showed significant improvement after the recruitment maneuver in both groups compared with baseline values. However, measurements obtained before the end of surgery and after extubation were significantly higher in Group II than in Group I (P < 0.001). Lung mechanics were also significantly better in Group II, with higher compliance, lower driving pressure, and reduced plateau pressure (Pplat). Intraoperative hypoxia requiring rescue therapy occurred in 10 patients (33.3%) in Group I compared with 2 patients (6.7%) in Group II, while postoperative hypoxia requiring supplementary oxygen was observed in 7 patients (23.3%) in Group I and in none of the patients in Group II. CONCLUSION: The adoption of driving pressure-based ventilation in laparoscopic bariatric surgery for morbidly obese patients was associated with improved oxygenation, optimized lung mechanics, and a lower risk of postoperative hypoxemia. TRIAL REGISTRATION: The trial was registered prior to patient enrolment at ClinicalTrials.gov (NCT04861168, Date of registration: 27/4/2021).