Abstract： Objective To investigate the effects of oral intake of glucose solution before surgery on the pH at the lower esophagus,perioperative blood glucose level,and plasmic protein in patients undergoing radical resection for colorectal cancer.Methods Between January 2008 and December 2008,60 patients undergoing radical surgery for colorectal cancer were enrolled and randomized into three groups using the table of random digits.Four patients were withdrawn from the study.Patients in group A (n=19) were given 800 ml of 12.5% glucose solution for oral intake the night before surgery,and 200 ml two hours before surgery.Patients in group B (n=19) were given distilled water instead of glucose.Patients in group C (n=18) were asked to fast for 8-12 hours before operation.Combined general and epidural anesthesia was used.pH at the lower esophagus was monitored during intubation and extubation.Albumin,transferrin,prealbumin,insulin,and fasting blood glucose were measured before surgery and at postoperative day 1,3,and 7.Results pH at the lower esophagus was 8.05±0.43 in group A,7.98±0.41 in group B,and 7.94±0.41 in group C.There were no perioperative acid regurgitations (P＞0.05).Serum insulin in group A at postoperative day 1 was (16.32±16.11) μU/L,which was significantly lower than that in group B (30.65±41.74)μU/L and group C (34.01 ±52.91 ) μU/L.Log HOMA-IR in group A at postoperative day 1 was significantly lower than that in group B and group C (0.49±0.35 vs.0.59±0.56 and 0.60±0.63,P＜0.05).Transferrin in group C at postoperative day 3 and 7 was significantly lower than that in the other two groups,as was albumin at postoperative day 3(P＜0.05).Conclusion Oral liquid intake 2 hours before surgery is not associated with increased risk of regurgitation or aspiration during intubation and extubation,and may glucose solution intake reduce insulin resistance and protein degradation after colorectal surgery.