Postoperative hyperglycemia after 4-vs 8-10-mg dexamethasone for postoperative nausea and vomiting prophylaxis in patients with type II diabetes mellitus: a retrospective database analysis

Study objective: The study objective is to compare change in postoperative blood glucose from preoperative values in patients with type II diabetes mellitus receiving 4- or 8-10-mg dexamethasone for postoperative nausea and vomiting prophylaxis. Design: This is a retrospective database study. Setting: The setting is at an academic university medical center. Patients: There are 1037 adult patients, American Society of Anesthesiologists physical status I-TV, with type II diabetes mellitus, undergoing elective surgery between January 1, 2006, and March 31, 2012, and who were hospitalized for at least 24 hours. Interventions: The interventions are dexamethasone 4 or 8-10 mg for postoperative nausea and vomiting prophylaxis. Measurements: Age, sex, American Society of Anesthesiologists class, height, weight, body mass index, surgery date, type and duration of surgery, hemoglobin Ale (HbA1c) within 180 days of surgery, type of anesthesia, preoperative blood glucose in the preoperative holding area, maximum blood glucose in the postanesthesia care unit (PACU) and first 24 hours postoperatively, and insulin requirements intraoperatively and in PACU. Main results: In unadjusted analysis, the 8-10-mg dose was associated with greater (mean +/- SD) increase in blood glucose compared with the 4-mg dose in PACU (58 +/- 50 vs 43 +/- 45 mg/dL, P < .0001) and over 24 hours (101 +/- 71 vs 67 +/- 65 mg/dL, P < .0001). In the multivariable model, predictors of blood glucose increase in PACU included dexamethasone dose (P < .0001), preoperative serum glucose (P < .0001), duration of surgery (P < .0001), and total dose of insulin (P < .0001). Over 24 hours, the significant predictors of glucose increase included dexamethasone dose (P < .0001), preoperative blood glucose level (P < .0001), duration of surgery (P < .0001), year of surgery (P = .04), and neurosurgical procedures (P = .02). This model estimates the increase in postoperative glucose to be 25 mg/dL higher over 24 hours with dexamethasone 8-10 mg than with 4 mg (95% confidence limits, 18-32 mg/dL). Conclusions: Dexamethasone 8-10 mg is associated with a significantly greater perioperative increase in blood glucose compared with a 4-mg dose. (C) 2015 Elsevier Inc. All rights reserved.