Preoperative carbohydrate loading with individualized supplemental insulin in diabetic patients undergoing gastrointestinal surgery: A randomized trial

•Preoperative carbohydrate drink is an important content of Enhanced Recovery After Surgery (ERAS) bundle.•Preoperative carbohydrate loading with individualized supplemental insulin is feasible in diabetic patients.•This regimen does not promote gastrointestinal recovery such as time to first flatus, but improved perioperative well-being.