Effects Of Preoperative Oral Carbohydrate Versus Placebo On Postoperative Insulin Resistance In Radical Gastrectomy Patients:a Single-center Double-blind, Randomized Controlled Clinical Trial

Objective:To evaluate the safety of preoperative oral carbohydrate in radical gastrectomy patients and to investigate the effects of postoperative insulin resistance and its possible mechanism.Methods:From April to October2011, sixty consecutive gastric cancer patients met inclusion criteria were divided into oral carbohydrate group and placebo group by randomized double-blind principles in Qingdao University Medical School Hospital. Resting energy expenditure, fasting blood glucose, insulin and triglyceride level were detected4hours preoperatively.500ml carbohydrate or placebo were administrated orally2-3hours before the. Anaesthesia. Two group patients underwent radical distal subtotal gastrectomy under epidural compounded intravenous anesthesia, After laparotomy and before the abdomen was closed, a piece of rectus abdominis muscle was taken and fixed in3%glutaraldehyde solution, Any blood products, glucose and insulin were not used during the operation. Resting energy expenditure, fasting blood glucose, insulin and triglyceride level were detected immediately after surgery. The changes of insulin resistance index, blood triglycerides level, resting energy expenditure and respiratory quotient were compared pre-and post-operatively. The changes of rectus abdominis muscle mitochondrial ultrastructure were observed by transmission electron microscopy and surgical complications were recorded respectively in two groups.Results:There were48patients (34males and14females) completed the trial. Oral placebo and carbohydrate groups were compared respectively, post-operative insulin resistance index wasl2.68±3.13and5.679±1.40(t=6.646,p=0.003); resting energy was 1458.21±168.54and1341.00±110.28Kcal/d (t=2.851, p=0.046); respiratory quotient was0.73±0.42and0.79±0.22(t=6.546, p=0.041), serum triglyceride level was0.53±0.24and1.04±0.97g/L (t=2.542, p=0.006), the rectus abdominis muscle mitochondrial damage index was1.14±0.33and0.92±0.19(t=2.73, p=0.028), there were a significant differences between two groups. Oral placebo group showed a markedly swollen mitochondria, steep membrane was not clear, mitochondria appeared vacuolated changes.Conclusions:Preoperative oral carbohydrate can reduce the insulin resistance and resting energy expenditure, improve the material metabolism status in radical gastrectomy patients. The possible mechanisms should be related to promotion of insulin release and protection of mitochondrial function.