Effects of preoperative and postoperative carbohydrate loading on gastrointestinal function and stress-induced inflammation after radical prostatectomy

Background: Early postoperative oral clear liquid diet has been shown to enhance postoperative recovery. However, the standard strategy for this diet has not been established. The authors’ aim was to investigate the combined effect of preoperative and early postoperative carbohydrate loading on postoperative stress and gastrointestinal function of patients by standardizing the starting time, type, volume, and concentration of carbohydrate drinks. Materials and methods: Fifty-three patients undergoing radical prostatectomy were randomly assigned to two groups. Both groups received a carbohydrate loading of 400 ml (12.5%) overnight and 2 h before surgery. The intervention group (n=29) started a 400 ml (12.5%) carbohydrate loading 6 h after surgery and consumed it within 24 h, while the control group (n=32) drank water. The primary outcomes–postoperative fasting blood glucose, fasting insulin, C-reactive protein (CRP), interleukin-6 levels, and gastrointestinal function–were recorded. Secondary outcomes included subjective comfort assessment, the first postoperative intake of semi-fluid food time, and drainage volume. Results: Compared with the control group, the intervention group had lower CRP levels on postoperative day 1 (POD1)/POD2 and less drainage volume on POD1. The intervention group also experienced shorter times to the first postoperative flatus and the first consumption of semi-fluid foods; their 72-h postoperative protein intake was higher than that of the control group. Conclusion: The results suggest that combined preoperative and postoperative carbohydrate loading can alleviate stress-induced inflammation and promote the recovery of postoperative gastrointestinal function.