BACKGROUND

The study was undertaken to observe the effect of different maintenance fluid regimen on intraoperative blood glucose levels in nondiabetic patients undergoing elective major noncardiac surgery under general anaesthesia.

METHODS

Two hundred nondiabetic patients (100 in each group) aged between 18 and 60 yrs were enrolled for this prospective randomized parallel group study. 

Group A patients received Ringer’s lactate solution and group B patients received 0.45% sodium chloride with 5% dextrose and 20 mmol/L potassium chloride as maintenance fluid. Capillary blood glucose (CBG) level was measured immediately before initiation of intravenous fluid therapy and there after hourly till the end of surgery.

If at any time intraoperative CBG was found to be more than or equal to 150 mg/dL calculated dose of human soluble insulin was given as intravenous bolus equal to the amount of CBG/100 units.

RESULTS

63% patients in group B developed at least one episode of hyperglycemia (CBG ≥ 150 mg/dL) but only 29% in the group A did so.  Insulin consumption was significantly higher in group B than in group A to maintain normoglycemia. The relative risk of becoming hyperglycemic in group B patients is 2.172 (95% CI 1.544 to 3.057). Number needed to harm, i.e. hyperglycemia, in group B is 2.941 (95% CI 2 to 5).

CONCLUSION

We conclude that stress induced hyperglycemic response in patients undergoing major noncardiac surgery is common in nondiabetic population.  Maintenance fluid therapy by dextrose containing solution as opposed to RL solution increases the incidence of hyperglycemia. To achieve normoglycemia by intravenous bolus dose of human regular insulin, significantly higher doses are required in patients receiving dextrose containing saline as maintenance fluid.