- PNP pneumoperitoneum period, POD1 postoperative day 1, POD3 postoperative day 3, PEEP positive end-expiratory airway pressure, iPEEP individual PEEP, RM recruitment maneuver, EIT electrical impedance tomography, PNP pneumoperitoneum, PPCs postoperative pulmonary complications, POD postoperative day, ICU intensive care unit