Effect of IV dextrose administration on glucose metabolism during surgery

BACKGROUND: The inhibitory influence of exogenous dextrose on glucose production has been shown to be less pronounced during injury and sepsis. This protocol was designed to investigate the effect of i.v. hypocaloric dextrose on glucose metabolism during elective abdominal surgery. METHODS: Fourteen patients with rectal cancer were studied under fasting conditions and toward the end of a 3‐hour infusion of dextrose (2 mg.kg‐1 per minute) either in absence (control group, n = 7) or presence of colonic surgery (surgery group, n = 7). Endogenous glucose production was determined by using primed continuous infusions of 6,6–2H2glucose before and during dextrose administration. We also measured the plasma concentrations of glucose, lactate, cortisol, glucagon, and insulin. RESULTS: The administration of dextrose decreased the endogenous glucose production in all patients (p <.05). This decrease was less pronounced during surgery (p <.05). Plasma glucose concentration increased during dextrose infusion in both groups (p <.05), with higher values in the surgery group than in the control group (p <.05). Plasma concentrations of lactate and glucagon remained unaltered. Dextrose infusion increased the plasma insulin concentrations to the same extent in both groups (p <.05). Cortisol plasma levels increased only in the surgery group (p <.05). CONCLUSIONS: Surgical stress blunts the inhibitory effect of i.v. dextrose on endogenous glucose production.