Preoperative fasting has been a routine practice in many hospitals to prevent aspiration of gastric contents during surgery. However, recent evidence suggests that oral intake of clear liquids, including commercial carbohydrate preparations, up to two hours before surgery is safe and does not affect gastric content or acidity. These carbohydrate solutions have shorter gastric transit times and can reduce postoperative thirst, hunger, dehydration, headache, nausea, and vomiting.
A study was conducted in our anesthesia department, where 100 patients undergoing elective surgery under general anesthesia were selected and divided into two groups. One group received preoperative carbohydrate-rich fluid (carboload 50g in 350ml of water) two hours before surgery, while the other group received clear fluids (black tea, black coffee, or water). Postoperatively, the incidence of postoperative nausea and vomiting (PONV) was evaluated using the PONV impact score at 1 hour, 6 hours, and 24 hours. Gastric residual volume was also measured using a 14G Ryles tube.
The PONV impact score was significantly lower in the group administered carboload compared to the clear fluid group (p value < 0.001). The gastric residual volume was also lower in the carboload group (p value – 0.002).
Administering carbohydrate-rich fluid two hours before surgery reduced the incidence of postoperative nausea and vomiting without increasing gastric residual volume.