Dexamethasone for preventing nausea and vomiting associated with epidural morphine: A dose-ranging study

We conducted a dose-ranging study of dexamethasone for preventing nausea an d vomiting within the first 24 h after the administration of epidural morph ine. Two hundred twenty-five women (n = 45 in each of the five groups) unde rgoing simple abdominal total hysterectomy under epidural anesthesia were e nrolled in this randomized, double-blind, placebo-controlled study. When th e incision closure was completed, patients received IV dexamethasone, 10 mg , 5 mg, or 2.5 mg; IV droperidol 1.25 mg; or saline 2 mL. All patients rece ived epidural morphine 3 mg for postoperative analgesia. We found that pati ents who received dexamethasone 5 mg or 10 mg or droperidol 1.25 mg were si gnificantly different from those who received saline alone in the following variables: the total incidence of nausea and vomiting, the incidence of mo re than four vomiting episodes, the number of patients requiring rescue ant iemetics, the total number of patients with no vomiting and/or no antiemeti c medication (P < 0.05 to P < 0.01). The differences among dexamethasone 10 mg and 5 mg and droperidol 1.25 mg were not significant. Dexamethasone 2.5 mg was ineffective. In conclusion, because dexamethasone 5 mg was as effec tive as 10 mg as an antiemetic, we recommend the smaller dose for preventin g nausea and vomiting associated with epidural morphine.