Although there are many studies of hypo- or hyperglycemia on gastric function, no studies have been conducted to determine the effect of glycemic status on preoperative gastric contents especially in pregnant women. We investigated the effect of dextrose infusion on preoperative gastric contents and serum gastrin in overfasting pregnant patients.

After six hours of fasting, forty pregnant patients scheduled for elective cesarean section were randomly assigned to one of two groups to receive either 120 ml/h of 5% dextrose fluid (Dextrose group, n = 20) or same rate of normal saline (Control group) until the induction of anesthesia. Before the start of combined spinal-epidural anesthesia, gastric contents were gently aspirated using a 14-F multiorifice nasogastric tube (Levin tube, Yushin Medical, Shiheung, Korea). Blood samples for the serum gastrin and glucose concentrations were taken.

Aspirated gastric pH (2.7 vs. 2.9) and volumes (28.5 vs. 26.5 ml) were similar in the two groups. However, significantly more patients (40%) in the control group were found to be at risk of aspiration syndrome, pH < 2.5 and volume > 25 ml, than in the dextrose group (20%). The serum gastrin concentrations of the two groups were not significantly different (32.8 vs. 27.1 pg/ml). Preoperative glucose concentration did not correlate with gastric pH or volumes, but with serum gastrin concentration (tau-b = -0.347, vs. -0.466, P = 0.02).

Preoperative dextrose infusion can decrease the number of patients at risk for pulmonary acid aspiration in overfasting pregnant women undergoing cesarean delivery.