Individualized vs Standard PEEP and Oxygen Reserve Index in Laparoscopic Hernia Surgery

Condition(s) studied

Investigational drug(s) / intervention(s)

Standard PEEP Ventilation: Mechanical ventilation with a fixed positive end-expiratory pressure (PEEP) of 5 cmH₂O applied throughout the surgical procedure. Volume-controlled ventilation mode with tidal volume 6-8 ml/kg ideal body weight, inspiratory-to-expiratory ratio 1:2, and fraction of inspired oxygen (FiO₂) 0.40. Respiratory rate adjusted to maintain end-tidal CO₂ (EtCO₂) between 35-40 mmHg. No recruitment maneuver is performed.

Individualized PEEP Ventilation: Individualized PEEP determined by a stepwise recruitment maneuver followed by PEEP titration, applied at 10 minutes after Trendelenburg positioning. The optimal PEEP level is identified based on best dynamic lung compliance and maintained for the remainder of surgery. All other ventilation parameters are identical: volume-controlled mode, tidal volume 6-8 ml/kg, I/E ratio 1:2, FiO₂ 0.40, EtCO₂ 35-40 mmHg.

Study summary

During laparoscopic surgery under general anesthesia, lung function can be affected by increased abdominal pressure and patient positioning. Positive end-expiratory pressure (PEEP) is a ventilator setting that helps keep the lungs open during surgery. In standard practice, a fixed PEEP level is applied to all patients. An individualized PEEP approach tailors this setting to each patient based on lung recruitment maneuvers.

This study investigates whether individualized PEEP improves oxygenation compared to standard PEEP in patients undergoing laparoscopic inguinal hernia surgery. Oxygenation will be continuously monitored using the Oxygen Reserve Index (ORI), a non-invasive sensor. Lung aeration will also be assessed before and after surgery using bedside lung ultrasound.

Eligibility

Primary outcome measure(s)

• Perioperative Oxygenation Assessed by Oxygen Reserve Index (ORI) — From anesthesia induction to postoperative 20 minutes (approximately 3 hours)
  Continuous non-invasive monitoring of the Oxygen Reserve Index (ORI) to assess perioperative oxygenation. ORI values range from 0 to 1 and reflect partial oxygen pressure changes in the 100-200 mmHg range. ORI is recorded at six time points: before anesthesia induction (T0), 5 minutes after intubation (T1), 10 minutes after Trendelenburg positioning (T2), 20 minutes after Trendelenburg positioning (T3), after desufflation (T4), and at postoperative 20 minutes (T5). ORI values will be compared between the standard PEEP and individualized PEEP groups.

Trial sites (1)

More Fatih Sultan Mehmet Training and Research Hospital trials in Turkey

Other trials for the same condition