title: The effectiveness of rescue antiemetics after failure of prophylaxis with ondansetron or droperidol: a preliminary report.
abstract: OBJECTIVE
  To compare the effectiveness of treating established postoperative nausea and vomiting (PONV) with an antiemetic acting at a different receptor with that of treating PONV with the antiemetic used for prophylaxis.
  
  
  METHODS
  Analysis of data collected in a previously published randomized, double-blind, placebo-controlled study.
  
  
  METHODS
  Outpatient surgical procedures from 50 institutions in North America.
  
  
  METHODS
  Patients (N = 2061) undergoing outpatient surgical procedures planned to last no more than 2 hours.
  
  
  METHODS
  Patients were randomized to receive ondansetron 4 mg, droperidol 1.25, droperidol 0.625 mg, or placebo. In the postoperative anesthesia care unit, patients who developed PONV received rescue antiemetics at the discretion of the attending anesthesiologist. The following antiemetics were used for rescue: ondansetron 4 mg, droperidol 0.625 to 1.25 mg, metoclopramide 10 mg, promethazine 6.25 to 25 mg, and dimenhydrinate 25 to 50 mg.
  
  
  METHODS
  The complete response rate (no nausea, no emesis, and no need for further rescue) after administration of the rescue antiemetic in patients with established PONV was calculated. The complete response rate after administration of each of the different rescue antiemetics was compared with that after administration of the same antiemetic used for PONV prophylaxis.
  
  
  RESULTS
  In patients who failed prophylaxis with ondansetron 4 mg, the complete response rate was significantly higher (P = .02) after rescue with promethazine 6.25 to 25 mg (78%) than after rescue with ondansetron 4 mg (46%). In patients who failed prophylaxis with droperidol 0.625 and 1.25 mg, the complete response rate was significantly higher after rescue with promethazine 6.25 to 25 mg (77%; P = .02) and dimenhydrinate 25 to 50 mg (78%; P = .04) than after rescue with droperidol 0.625 to 1.25 mg (56%).
  
  
  CONCLUSIONS
  In patients who failed prophylaxis with ondansetron or droperidol, promethazine was significantly more effective than the agent used for prophylaxis for the treatment of PONV. In patients who failed prophylaxis with droperidol, dimenhydrinate was also more effective than droperidol for the treatment of established PONV in the postoperative anesthesia care unit.
authors.affiliation: Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: Ashraf S
authors.initials: AS
authors.lastname: Habib
authors.forename: Tong J
authors.initials: TJ
authors.lastname: Gan
mesh_terms: D000328:Adult; D000368:Aged; D000556:Ambulatory Surgical Procedures; D000932:Antiemetics / Q000627:therapeutic use*; D004111:Dimenhydrinate / Q000627:therapeutic use; D004329:Droperidol / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008787:Metoclopramide / Q000627:therapeutic use; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D009656:North America; D017294:Ondansetron / Q000627:therapeutic use*; D020250:Postoperative Nausea and Vomiting / Q000188:drug therapy* / Q000517:prevention & control*; D011398:Promethazine / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic; D017211:Treatment Failure
chemical_list: D000932:Antiemetics; D017294:Ondansetron; D011398:Promethazine; D004111:Dimenhydrinate; D008787:Metoclopramide; D004329:Droperidol