Preoperative fasting period of fluids in bariatric surgery

Abstract

Aspiration of stomach content is asevere complication during general anaesthesia. The DGAI (German Society for Anesthesiology and Intensive Care Medicine) guidelines recommend afasting period for liquids of 2 h, with amaximum of 400 ml. Preoperative fasting can affect the patients' recovery after surgery due to insulin resistance and higher protein catabolism as aresponse to surgical stress. The aim of the study was to compare aliberal fasting regimen consisting of up to 1000 ml of liquids until 2 h before surgery with the DGAI recommendation. The prospective observational clinical study was approved by the ethics committee of the University of Leipzig. In the liberal fasting group (Glib) patients undergoing bariatric surgery were asked to drink 1000 ml of tea up to 2 h before surgery. Patients assigned to the restrictive fasting group (Gres) who were undergoing nonbariatric abdominal surgery were asked to drink no more than 400 ml of water up to 2 h preoperatively. Right after anaesthesia induction and intubation agastric tube was placed, gastric residual volume was measured and the pH level of gastric fluid was determined. Moreover, the occurrence of aspiration was monitored. In all, 98patients with abody mass index (BMI) of Glib 51.1 kg/m2 and Gres 26.5 kg/m2 were identified. The preoperative fasting period of liquids was significantly different (Glib 170 min vs. Gres 700 min, p< 0.001). There was no difference regarding the residual gastric volume (Glib 11 ml, Gres 5 ml, p= 0.355). The pH of gastric fluid was nearly similar (Glib4.0; Gres3.0; p= 0.864). Aspiration did not occur in any patient. There is evidence suggesting that aliberal fluid fasting regimen (1000 ml of fluid) in the preoperative period is safe in patients undergoing bariatric surgery.