Effects of Postural Recruitment Maneuver and Positive End-Expiratory Pressure on Lung Atelectasis during Laparoscopic Cholecystectomy Surgery: A prospective, randomized study

General anaesthesia leads to lung atelectasis, even in healthy parenchyma. This pathophysiologic alteration is a result of decrease in functional residual capacity and respiratory compliance, due to compression of lung parenchyma by abdominal viscera, especially in dependent areas of lung. The creation of pneumoperitoneum during laparoscopic surgery further augments these changes, leading to increased risk of hypoxemia and pulmonary complications during perioperative period. Mechanical ventilation by-itself is insufficient to offset these compressive effects due to low transpulmonary pressure, especially in gravity-dependent zones of lung. Different approaches have been tried to minimize these changes, including head-up position, application of intraoperative positive end expiratory pressure (PEEP), or recruitment maneuver (RM) etc. The RM has been found to most effective in reverting atelectasis, among all strategies. However, potential hemodynamic complications of high transthoracic pressures by RM require close haemodynamic monitoring of such patients, especially in laparoscopic surgery exposing the patient to detrimental effects of capnoperitoneum. Postural recruitment maneuver (PRM) have been suggested as an effective and efficient low risk alternative to RM in a recent brief communication. Changing the body position while applying PEEP of 10 cmH2O for just 3 min, prevented atelectasis in mechanically ventilated children under general anaesthesia. Our aim is to assess the effects of postural recruitment maneuver and positive end-expiratory pressure on lung atelectasis during laparoscopic cholecystectomy surgery.