Effect of preoperative oral rehydration on postoperative recovery in patients undergoing laparoscopic radical resection of colorectal cancer

Objective To evaluate the effect of preoperative oral rehydration on postoperative recovery in patients undergoing laparoscopic radical resection of colorectal cancer. Methods Eighty patients of both sexes, aged 18-64 yr, with body mass index of 18-24 kg/m2, of American Society of Anesthesiologists physical status ⅠorⅡ, scheduled for elective radical resection of colorectal cancer, were randomly divided into either routine fluid replacement group (group R) or oral rehydration group (group O) with 40 patients in each group.Fasting for solid food was performed at 8 h before surgery and for water at 6 h before surgery, and fluid was replaced according to the volume expansion during induction and 4-2-1 formula in group R. In group O, multivitamin drinks containing sugar and electrolyte was given orally according to the fasting time: 12-15 ml/kg at 8 h of fasting, 15-20 ml/kg at 8-12 h of fasting, with the total volume not exceeding 1 200 ml, 300 ml at 3 h before surgery, and the rest of fluid was given at different times the night before surgery, and fluid replacement 1 200 ml was performed according to the basic requirement of patients and intraoperative fluid loss.Fluid replacement was maintained at a rate of 1.5 ml·kg-1·h-1 on the day of surgery in two groups.The volume of oral fluid intake, intraoperative net volume of fluid intake and volume of intravenously given fluid on the day of surgery were recorded.The time of surgery, emergence time, time to first flatus, time to first liquid diet, first ambulation time and length of postoperative hospital stay were recorded.The development of postoperative nausea and vomiting and hypotension was recorded.Peripheral venous blood samples were collected on the morning of day 2 after admission to hospital, the day of surgery and day 1 after surgery (T0-2) for determination of the fasting blood glucose and insulin concentrations, and insulin resistance index was calculated. Results Thirty-seven and 35 patients were included in R and O groups, respectively.Compared with group R, the intraoperative net volume of fluid intake and volume of intravenously given fluid on the day of surgery were significantly decreased, fasting blood glucose and insulin concentrations and insulin resistance index were decreased, and the time to first flatus, time to first liquid diet and length of postoperative hospital stay were shortened in group O (P<0.05). Conclusion Preoperative oral rehydration can promote postoperative recovery, which may be related to mitigating insulin resistance in patients undergoing laparoscopic radical resection of colorectal cancer. Key words: Fluid therapy; Rehabilitation; Colorectal neoplasm; Laparoscopy