Efficacy of carbohydrate loading for preoperative preparation in patients undergoing cesarean section under epidural anesthesia

Objective To evaluate the efficacy of carbohydrate loading for preoperative preparation in the patients undergoing cesarean section under epidural anesthesia. Methods Forty American Society of Anesthesiologists physical statusⅠpatients, aged 20-35 yr, with body mass index of 19-30 kg/m2, scheduled for elective cesarean section, were divided into 2 groups(n=20 each)by envelope method: carbohydrate group(group CA)and placebo group(group C). Carbohydrate drinks 300 ml containing carbohydrate 14.1 g/100 ml was taken orally at 2 h before surgery in group CA, and the equal volume of distilled waster was taken orally instead in group C. Patients underwent routine preoperative fasting on the night before surgery, continuous epidural anesthesia was used, and lactated Ringer′s solution 1 500 ml was given to maintain the volume during surgery.Anteroposterior diameter and left-right diameter of gastric antrum and area of gastric antrum in this section were measured at fasting, immediately after oral intake and at 2 h after oral intake in group CA.Venous blood samples were collected after delivery of the baby for determination of serum malondialdehyde concentrations by competitive enzyme-linked immunosorbent assay.Thirst, hunger and anxiety scores were recorded after entering the operating room.The development of nausea and vomiting was also recorded in 0-12 h and 12-24 h periods postoperatively. Results Compared with group C, the hunger scores and concentration of serum malondialdehyde were significantly decreased(P 0.05). No significant changes were observed in anteroposterior diameter, left-right diameter and area of gastric antrum at 2 h after the oral intake when compared with that at fasting(P>0.05). Conclusion Carbohydrate loading at 2 h before surgery can improve the efficacy of preoperative preparation without increasing the risk of reflux or aspiration in the patients undergoing cesarean section under epidural anesthesia. Key words: Carbohydrate; Preoperative care; Cesarean section; Anesthesia, epidural