title: A dose ranging study of dexamethasone for preventing patient-controlled analgesia-related nausea and vomiting: a comparison of droperidol with saline.
abstract: We designed this study to determine the minimum dose of dexamethasone for preventing nausea and vomiting associated with the use of morphine by patient-controlled analgesia (PCA). Two hundred forty female patients were randomly assigned to receive dexamethasone 2, 4, 8, or 12 mg IV immediately before induction of anesthesia. Droperidol (0.1 mg/mL with morphine 1 mg/mL in PCA pump) and saline were used as controls. The complete response (no postoperative nausea and vomiting and no need for rescue antiemetic for a 24-h postoperative period) rates for dexamethasone 8 mg (72.2%) and 12 mg (78.9%) were significantly more than for saline (42.9%) (P < 0.05). Patients who received dexamethasone 12 or 8 mg also reported higher patient satisfaction than those who received saline (P < 0.05). These results were as effective as adding droperidol 0.1 mg/mL to the morphine PCA without causing drowsiness, restlessness, or arrhythmias. Smaller doses of dexamethasone (4 or 2 mg) were not effective for this propose. The results suggest that dexamethasone 8 mg IV is the minimum effective dose for the reduction of PCA morphine-related nausea and vomiting.
  
  
  CONCLUSIONS
  Morphine administration by patient-controlled analgesia (PCA) is often associated nausea and vomiting. In this double-blind study, the minimum effective dose of dexamethasone for reducing this complication was 8 mg. This was as effective as adding droperidol 0.1 mg/mL to the morphine PCA without causing drowsiness, restlessness or arrhythmias.
authors.affiliation: From the Department of Anesthesiology, Buddhist Tzu-Chi Medical Center, Tzu-Chi University School of Medicine, Hualien, Taiwan.
authors.forename: Yi
authors.initials: Y
authors.lastname: Lee
authors.forename: Hsien-Yung
authors.initials: HY
authors.lastname: Lai
authors.forename: Pei-Chin
authors.initials: PC
authors.lastname: Lin
authors.forename: Youh-Sun
authors.initials: YS
authors.lastname: Lin
authors.forename: Shen-Jer
authors.initials: SJ
authors.lastname: Huang
authors.forename: Ming-Hwang
authors.initials: MH
authors.lastname: Shyr
mesh_terms: D000368:Aged; D016058:Analgesia, Patient-Controlled / Q000009:adverse effects*; D000701:Analgesics, Opioid / Q000009:adverse effects; D000932:Antiemetics / Q000008:administration & dosage* / Q000627:therapeutic use*; D003907:Dexamethasone / Q000008:administration & dosage* / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004329:Droperidol / Q000008:administration & dosage* / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D009020:Morphine / Q000009:adverse effects; D010149:Postoperative Pain / Q000150:complications / Q000453:epidemiology; D020250:Postoperative Nausea and Vomiting / Q000517:prevention & control*
chemical_list: D000701:Analgesics, Opioid; D000932:Antiemetics; D009020:Morphine; D003907:Dexamethasone; D004329:Droperidol