title: Prospective application of a simplified risk score to prevent postoperative nausea and vomiting.
abstract: OBJECTIVE
  To compare the risk-adapted approach with ondansetron against ondansetron plus dexamethasone to prevent postoperative nausea and vomiting (PONV) in a randomized clinical trial.
  
  
  METHODS
  460 patients scheduled for elective surgery were enrolled in this prospective study and stratified according to a simplified risk score for PONV. Patients having no or one risk factor were considered at low risk (group L) and did not receive study medication. Those with two to four risk factors were considered high risk and were randomized to receive 4 mg ondansetron plus placebo (group H-O) or 4 mg ondansetron plus 8 mg dexamethasone (group H-OD). Incidence and intensity of PONV were observed for 24 hr after surgery. Data were analyzed with Fisher's exact or Student's t tests; P < 0.05 was considered statistically significant.
  
  
  RESULTS
  The incidence of PONV was 9% in group L (n = 87), 31% in those receiving ondansetron (group H-O, n = 185), and 22% in those receiving both drugs (group H-OD, n = 181). The incidence of PONV was significantly smaller in both high-risk groups than predicted without treatment (P < 0.001). While the incidence of PONV failed statistical significance between the two intervention groups (P = 0.08), the mean number of episodes of PONV and the mean maximal intensity of each episode of PONV were lower in group H-OD (P = 0.03 and P = 0.01, respectively). Patients of group H-OD required less antiemetic rescue therapy (P = 0.004).
  
  
  CONCLUSIONS
  Ondansetron plus dexamethasone prevents PONV more effectively than ondansetron alone in patients at high risk for PONV.
authors.affiliation: Klinik für Anästhesiologie und Operative Intensivmedizin, Universitätsklinikum Schleswig-Holstein, Campus Kiel, Germany. ruesch@staff.uni-marburg.de
authors.forename: Dirk
authors.initials: D
authors.lastname: Rüsch
authors.forename: Leopold
authors.initials: L
authors.lastname: Eberhart
authors.forename: Andreas
authors.initials: A
authors.lastname: Biedler
authors.forename: Jürgen
authors.initials: J
authors.lastname: Dethling
authors.forename: Christian C
authors.initials: CC
authors.lastname: Apfel
mesh_terms: D000328:Adult; D000368:Aged; D003907:Dexamethasone / Q000008:administration & dosage* / Q000009:adverse effects; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D017294:Ondansetron / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D020250:Postoperative Nausea and Vomiting / Q000453:epidemiology / Q000517:prevention & control*; D011446:Prospective Studies; D012306:Risk
chemical_list: D017294:Ondansetron; D003907:Dexamethasone