Effect of Low-Dose Dexamethasone on the Incidence of Hyperglycemia Following Surgery

The question of a possible hyperglycemic effect from single-dose dexamethasone is an important issue for clinicians managing patients in the intraoperative and postoperative periods. Recent evidence suggests that even moderate elevations in blood glucose levels may be associated with adverse events. The aim of this clinical investigation is to determine whether standard clinical doses of dexamethasone produce hyperglycemia in the perioperative period.

Patients will be randomized on the morning of surgery to one of six groups; dexamethasone 4mg groups (0-4 hour group, 8-24 hour group), dexamethasone 8 mg groups (0-4 hour group, 8-24 hour group), or a placebo group(0-4 hour group, 8-24 hour group). Randomization will be performed using the sealed envelope method (on the basis of a block-randomized computer-generated list). The drug/placebo solution will be prepared by the pharmacy into a syringe (either 2cc of dexamethasone (8mg), 1cc dexamethasone (4mg) + 1cc normal saline, or 2cc of saline (placebo)) and delivered to one of investigators. All solutions are clear and appear identical. Patients in the dexamethasone groups will receive a standard intraoperative dose of dexamethasone (either 4mg or 8 mg) intravenously at the induction of anesthesia. Patients in the placebo groups will receive 2 cc of saline at induction of anesthesia. Study syringes will be prepared by the pharmacy, and all clinicians will be blinded to group assignment. Primary Outcome Variable Serum Glucose levels: In the 0-4 hour patients, Blood glucose concentrations will be measured at 5 time intervals: at induction of anesthesia and at 60, 120, 180, and 240 minutes after the dexamethasone is administered. In the 8-24 hour patients, blood glucose levels will be measured at induction of anesthesia and at at 8- and 24-hours after induction. All blood samples will be measured using a portable glucometer which is calibrated daily. Blood glucose will be calculated by measuring a fingerprick capillary blood sample. The blood samples will be collected while the patient is under anesthesia and recovering from surgery. Secondary Outcome Variables Pain scores: Postoperative pain scores will be assessed using 100 mm visual analog scale (VAS) in which 0 represents no pain and 100 represents the worst pain imaginable. Pain scores will be measured at rest and with movement at 1 and 2 hours following surgery. Nausea and vomiting scores: The incidence of nausea will be quantified using a verbal rating scale (VRS- 0=no nausea, 1=mild nausea, 2=moderate nausea, 3=severe nausea). The incidence of vomiting was quantified on a 4-point scale; 0 = (none) no episodes, 1= (mild) 1 episode, 2= (moderate) 2-3 episodes, 3= (severe) more than 3 episodes. Nausea and vomiting scores will be obtained at discharge from the PACU. PACU data: Episodes of nausea and vomiting will be recorded. Requirements for pain medication and antiemetic medication will be recorded. The time needed to meet discharge criteria and achieve actual discharge will be noted.

Inclusion Criteria: Patients presenting for elective gynecologic surgery Exclusion Criteria: Age < 18 or > 90, patients receiving chronic or preoperative steroids,or allergy to dexamethasone.