Individualized Versus Fixed Positive End-Expiratory Pressure (PEEP) in Patients Undergoing Laparoscopic Surgery
Abstract
Background: Laparoscopic surgery is accompanied by the development of pneumoperitoneum, modified body positioning, and anesthesia that can cause a decrease in the functional residual capacity and respiratory compliance and cause atelectasis. Objective: To compare individualized PEEP versus fixed PEEP in relation to intra-operative oxygenation, lung mechanics, arterial blood gas analysis, postoperative oxygen saturation, atelectasis and post-operative pulmonary complications in patients undergoing elective laparoscopic surgery. Methodology: An RCT conducted at the Ayyub Teaching Hospital was carried out involving 96 patients aged between 20-65 years with ASA classification of I to III, undergoing elective laparoscopic surgeries. The patients were divided into two groups, one receiving fixed PEEP of 5 cmH₂O while the other receiving PEEP between 5 and 15 cmH₂O. Measurements taken included respiratory compliance, driving pressure, arterial blood gas, respiratory mechanics, SpO2, atelectasis, and postoperative complications. Results: The use of individualized PEEP led to higher PaO2/FiO2 ratio but not statistically different from that of the fixed PEEP (361.17±52.47 vs. 343.88±61.69; p=0.143). Significant increase in PaO2 was observed (166.22±18.07 vs. 154.90±20.35 mmHg; p=0.005). Compliance increased and driving pressure decreased significantly. Atelectasis was less in patients with personalized PEEP (10.4% versus 31.3%; p=0.024). There were no significant differences in PaCO₂ levels or pulmonary complications after surgery. Conclusion : Individualized positive end-expiratory pressure (PEEP) according to respiratory compliance and driving pressure was correlated with better respiratory mechanics, increased PaO₂ and postoperative SpO₂, and reduced postoperative atelectasis as compared with 5 cmH2O PEEP. Nevertheless, there were no statistical differences in the primary outcome of PaO₂/FiO₂ ratio and the number of postoperative pulmonary complications.