Effect of Single Low-Dose Dexamethasone on Peri-operative Blood Glucose Levels

Abstract

Background: Post-operative nausea and vomiting (PONV) is the second most common complaint reported after surgery with an incidence of 30%-80%. PONV is associated with numerous morbidities, hence prevention is beneficial. Dexamethasone is used as a prophylactic anti-emetic agent, however, being a corticosteroid, it could cause hyperglycaemia which is associated with a number of other adverse effects. Objectives: To study the effect of a single low-dose intravenous dexamethasone given as a prophylactic anti-emetic agent on perioperative blood glucose levels. Methods: Eighty-eight women who had elective myomectomy or hysterectomy under combined spinal-epidural (CSE) anaesthesia were randomised into two groups of 44 each. Following baseline blood glucose estimation, one group had 4 mg (1 ml) of intravenous dexamethasone 1-2 seconds after blood glucose check while the control group had 1 ml of normal saline. Blood glucose was measured every hour intra-operatively and two-hourly post-operatively till 12 hours after drug administration. Nausea, vomiting, dyspepsia, pain, motor block duration and urinary output were assessed hourly. Results: The mean maximum change in blood glucose from baseline in the dexamethasone group was statistically significantly higher than in the control group, 51.00±26.57 mg/dl vs. 35.80±25.71 mg/dl (p = 0.007) so also was the mean maximum blood glucose, 153.93±31.63 mg/dl vs. 139.52±28.95 mg/dl (p = 0.028) respectively. Conclusion: Intravenous dexamethasone at a single, low-dose (4 mg) used as a prophylaxis for nausea and vomiting is associated with significant increase in blood glucose concentration.