The effect of preoperative carbohydrate loading in cardiac surgery with cardiopulmonary bypass

Background: Preoperative fasting reduces the risk of regurgitation and pulmonary aspiration during anesthesia but may increase patient discomfort and cause adverse metabolic effects. Preoperative oral hydration and energy supplementation loading has been recommended to improve patient experience and metabolic stability. Our study aimed to evaluate the effects of consuming carbohydrate (Maltodextrin 12.5%) before surgery on gastric residual volume, patient comfort, and postoperative blood glucose in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). Methods: This prospective controlled study enrolled 198 patients undergoing elective cardiac surgery with CPB. The intervention group (M, n = 95) received 400 ml of maltodextrin 12.5% 2 hours before anesthesia induction, while the control group (N, n = 103) fasted from midnight. Gastric residual volume was measured using ultrasound before anesthesia. Hunger, thirst, dry mouth, and overall comfort were assessed using a 0–5 subjective scale. Blood glucose was monitored at four postoperative time points. Results: Gastric residual volume was lower in group M (20.3 ± 12.3 ml) compared to group N (26.63 ± 15.29 ml), though the difference was not statistically significant (p = 0.069). No patients exceeded the aspiration risk threshold of 1.5 ml/kg, and no regurgitation events were observed. Group M reported significantly lower scores for hunger (1.6 ± 0.93 vs. 2.63 ± 1.29), thirst (1.48 ± 1.05 vs. 3.51 ± 1.31), and dry mouth (0.93 ± 0.88 vs. 3.55 ± 1.24) compared to group N (p < 0.05). Overall comfort was significantly higher in group M (3.8 ± 1.12) than in group N (2.6 ± 1.64) (p < 0.05). Postoperative blood glucose levels were consistently higher in group N than in group M at all time points, but the differences were not statistically significant (p > 0.05). Conclusion: Preoperative consumption of maltodextrin 12.5% 2 hours before cardiac surgery with CPB is safe, does not increase gastric residual volume, and significantly improves patient comfort by reducing hunger, thirst, and dry mouth. However, it does not affect postoperative blood glucose levels.