Effect of PEEP Titration on the Incidence of Elevated Driving Pressure in Laparoscopic Bariatric Surgery: A Randomized Superiority Trial

Background Suboptimal positive end-expiratory pressure (PEEP) settings may lead to cyclic lung overstress, especially in obese patients undergoing general anesthesia. We hypothesized that recruitment maneuvers (RM) followed by driving pressure–guided PEEP titration – before and during pneumoperitoneum – would reduce the incidence of elevated driving pressure (> 15 cmH₂O) during pneumoperitoneum. Method In this single-center, randomized, superiority trial, obese patients undergoing laparoscopic bariatric surgery were allocated into three groups: (1) recruitment maneuvers followed by driving pressure-guided PEEP titration (RMTP); (2) recruitment maneuvers followed by fixed PEEP (6 cmH₂O) (RMFP); or (3) no recruitment maneuvers with fixed PEEP (6 cmH₂O) (NRMFP). RMs were performed with incremental PEEP (6→10→15→20 cmH₂O) and inspiratory pressure (26→30→35→40 cmH₂O), whereas PEEP titration was conducted in a decremental fashion. The primary outcome was the incidence of driving pressure > 15 cmH₂O. Result Eighty-five patients were screened and 78 randomized. No between-group differences were observed before or after pneumoperitoneum. During pneumoperitoneum before RM, driving pressure > 15 cmH₂O occurred less frequently with RMTP than with RMFP and NRMFP (7.7% vs 42.3% and 42.3%; RR 5.50, 95% CI 1.35–22.42; P = 0.017). After RM, the incidence remained lower with RMTP (3.8%) compared with RMFP (26.9%; RR 7.00, 95% CI 1.92–52.96; P = 0.045) and NRMFP (42.3%; RR 11.00, 95% CI 1.53–79.17; P = 0.017). Secondary outcomes, including postoperative pulmonary complications and hemodynamic variables, were similar between groups. Conclusion Recruitment maneuvers combined with driving pressure–guided PEEP titration reduced the incidence of elevated driving pressure during pneumoperitoneum, even in a predominantly low-risk population. Trial registration Brazilian Registry of Clinical Trials, RBR-5tbdpy5. Registered on January 29, 2024.