Effect of intraoperative low tidal volume and conventional tidal volume on postoperative pulmonary complications

BACKGROUND: Although postoperative pulmonary complications may develop in all patients undergoing general anesthesia, there is still no clear data on the ideal intraoperative ventilation strategy. In this study, we aimed to investigate the effect of low tidal volume and conventional tidal volume ventilation applied intraoperatively in our hospital on postoperative pulmonary complications METHODS: In this prospective observational study, 379 patients who underwent non-cardiac major surgery lasting longer than 2 hours were studied. Body mass index (BMI), comorbid diseases, lowest intraoperative SpO₂ values, mean tidal volume values applied according to ideal body weight VTort/IVA were recorded for all patients. If available pH, PaO₂, PaCO₂, PaO₂/FIO₂ ratio data in the arterial blood gas sampling of the patient were recorded. Respiratory complaints of the patients were questioned during the postoperative 24th hour, 72nd hour and 7th day service visits. The information of the patients who were admitted to the postanesthetic care unit (Pacu) and whose need for mechanical ventilator continued, were noted. Postoperative posteroanterior chest radiographs were investigated from our hospital system and evaluated for the presence of atelectasis RESULTS: We could not find a statistically significant relationship between the development of postoperative pulmonary complications (PPC) and low VTort/IVA values (p=0.216). We concluded that prolonged surgery time was associated with increased PPC at 24 hours, 72 hours, and 7 days (p<0,001). The mean age in the group in which we detected PPC at the 24th hour and 72nd hour was higher than the other group (p=0.005). We found more complıcatıons in male gender and surgeries performed in the supine position (p=0,001). CONCLUSİONS: Intraoperative low tidal volume ventilation (4-6 ml/kg) has no effect on reducing the rate of postoperative pulmonary complications compared to conventional tidal volume (> 6 ml/kg) administration.