Effect of preoperative feeding on gastric emptying following spinal anesthesia: a randomized controlled trial

BACKGROUND: Preoperative fasting is associated with various untoward postoperative health problems. Previous studies have stressed the advantages of preoperative feeding with a carbohydrate-rich drink 2 hours before surgery; this protocol does not increase the risk of gastric-content aspiration but reduces the level of anxiety and thirstiness during the perioperative period. Spinal anesthesia with the local anesthetic bupivacaine can decrease gastric emptying in the early postoperative period. However, the effect of spinal anesthesia on the gastric emptying rate following preoperative feeding is unknown. The aim of this study was to determine the impact of preoperative feeding with a clear carbohydrate-rich drink on gastric emptying early after orthopedic surgery under spinal anesthesia. METHODS: A total of 110 patients scheduled for semi-elective orthopedic surgery under spinal anesthesia were included in a randomized controlled trial. Patients were randomly assigned to two groups: group 1 (56 patients) received a standardized 200 ml of clear carbohydrate-enriched drink orally 2 hours before surgery; group 2 (54 patients) acted as a control group with no preoperative feeding. Gastric emptying was evaluated with a paracetamol test at five time points: 15 min, 30 min, 60 min, 90 min and 120 min after administration of paracetamol. RESULTS: No significant differences were observed between the two groups in paracetamol plasma concentrations or area under the curve during the early postoperative period. CONCLUSION: In patients undergoing spinal anesthesia, preoperative feeding 2 hours before surgery had no influence on the gastric emptying rate, indicating that preoperative feeding does not increase the risk of gastric-content aspiration and can be given safely.