You are about to start an elective rhinoplasty on an adult patient. Knowing the patient is at risk for post-operative nausea and vomiting, you elective to give 8 mg of dexamethasone IV. Which of the following is true concerning this medication?
A. In a known diabetic patient, 8 mg of IV dexamethasone will cause a significant increase in blood glucose levels above placebo.
B. In a known diabetic patient, 8 mg of IV dexamethasone will not cause a significant increase in blood glucose levels above placebo.
C. In a non-diabetic patient, 8 mg of IV dexamethasone will increase blood glucose levels by 80-100 mg/dL
D. Blood glucose levels will increase a similar amount in non-diabetic and diabetic patients after 8 mg of dexamethasone IV.
Answer
The answer is B. This is surprising to me. I have often held this medication in diabetics due to fear of rampant hyperglycemia and the effects of this state (poor wound healing, increased mortality, decreased cellular immune function, etc.). This simply hasn't proven to be true. Blood glucose levels increase in almost all patients during surgery. Surgical stimulation leads to stress hormones which leads to increased glucose levels. The addition of 8 mg of IV dexamethasone does NOT increase this above placebo. The rise glucose levels during surgery in diabetic patients is not statistically different after placebo or IV dexamethasone. In NON-DIABETIC patients, this increase is exaggerated. The increase is non-diabetic patients is about 30 mg/dL more than the placebo. The conclusion from a recent paper was that the withholding of steroid prophylaxis from diabetic patients needs to be reconsidered. Interesting.