Investigation of the Effects of Lung Protective Mechanical Ventilation in Robotic Surgeries Performed in Trendelenburg Position

Background and Goal of Study: Robotic surgery performed under general anesthesia with pneumoperitoneum and deep Trendelenburg positioning may adversely affect respiratory mechanics and gas exchange. Lung-protective ventilation strategies, including recruitment maneuvers (RM) and individualized positive end-expiratory pressure (PEEP), have been proposed to mitigate these effects. This study aimed to evaluate the effects of stepwise recruitment maneuvers combined with individualized PEEP on hemodynamic variables, respiratory mechanics, gas exchange, and postoperative respiratory outcomes in patients undergoing robotic surgery in the Trendelenburg position. Methods: After approval by the Gazi University Hospital Medical Research Ethics Committee, data of patients who underwent robotic surgery between 2012 and 2022 were retrospectively reviewed. Patients were divided into two groups: fixed PEEP (Group 1, n = 123) and individualized PEEP combined with recruitment maneuvers (Group 2, n = 135). Recruitment maneuvers were performed using a stepwise PEEP increase technique after intubation (T1), after pneumoperitoneum insufflation (T2), after positioning in Trendelenburg (T3), and after desufflation and position correction (T4). Demographic data, intraoperative hemodynamic parameters, respiratory variables, and postoperative respiratory outcomes were recorded. Continuous variables were analyzed using the Student’s t-test or Mann–Whitney U test, and categorical variables were compared using the χ² test. A p value < 0.05 was considered statistically significant. Results: Mean arterial pressure values showed transient reductions in the individualized PEEP group during Trendelenburg positioning. End-tidal CO₂ levels were lower in the individualized PEEP group during pneumoperitoneum and Trendelenburg positioning. Lung compliance was higher in patients receiving individualized PEEP at all measured intraoperative time points. Postoperative respiratory events were observed in both groups. Conclusion: In patients undergoing robotic surgery in the Trendelenburg position, stepwise recruitment maneuvers combined with individualized PEEP were associated with improved intraoperative respiratory mechanics without clinically significant hemodynamic instability.