PEEP Titration Guided by Electrical Impedance Tomography in Laparoscopic Surgery The PEaRL Study

Background: Laparoscopic surgery has gained widespread adoption due to its minimally invasive nature, offering advantages such as reduced postoperative pain, shorter hospitalization, and faster functional recovery compared with traditional open surgery. Nevertheless, postoperative respiratory complications remain a major source of morbidity. Factors such as general anesthesia, the Trendelenburg position, and CO₂ pneumoperitoneum can impair respiratory mechanics, reduce total lung capacity, and promote atelectasis, leading to compromised gas exchange. Rationale: Positive end-expiratory pressure (PEEP) is routinely applied to prevent alveolar collapse and improve oxygenation during mechanical ventilation. However, the use of standardized, non-individualized PEEP levels may be suboptimal, as inappropriate settings can cause alveolar overdistension or persistent collapse. Personalized PEEP titration, tailored to patient-specific lung mechanics, has recently emerged as a promising strategy to minimize ventilator-induced lung injury (VILI). Methods and Tools: Electrical Impedance Tomography (EIT) is a non-invasive, bedside monitoring technique that enables real-time assessment of regional lung ventilation. By evaluating ventilated and non-ventilated lung areas, EIT can guide PEEP optimization and support individualized ventilatory management. Recent studies suggest that EIT-guided PEEP titration improves respiratory parameters and reduces atelectasis in patients undergoing major surgery. Objective: The present study aims to evaluate the efficacy of EIT-guided PEEP personalization in patients undergoing laparoscopic and robotic surgery. Primary endpoints include improvements in regional ventilation, respiratory system compliance, and intraoperative gas exchange, as well as postoperative pulmonary function.

Inclusion Criteria: * scheduled for laparoscopic abdominal surgery * informed consent signed Exclusion Criteria: * COPD * Acute respiratory failure * Hemodynamic instability * Pregnancy * Contraindications for EIT device