Incidence of akathisia after postoperative nausea and vomiting prophylaxis with droperidol and ondansetron in outpatient surgery: A multicentre controlled randomised trial.

BACKGROUND: Akathisia, a distressing movement disorder induced by butyrophenones, has been described with low doses of droperidol used for postoperative nausea and vomiting (PONV) prophylaxis, but the incidence remains unclear. OBJECTIVES: To determine the incidence of akathisia after PONV prophylaxis with two doses of droperidol in comparison with ondansetron, in patients undergoing ambulatory surgery. We hypothesised that the incidence of akathisia is higher with droperidol than that with ondansetron. DESIGN: Randomised controlled double blind trial. SETTING: Two University Hospital Centres and two private Clinics from January to September 2014. PATIENTS: Patients (n=297) undergoing general anaesthesia for ambulatory surgery were randomly allocated to receive PONV prophylaxis with droperidol (0.625 or 1.25 mg) or ondansetron 4 mg; patients of the three groups also received 4 mg of dexamethasone. Exclusion criteria were contraindication to droperidol and ondansetron, use of psychotropic medications or benzodiazepines or history of psychotic illness. INTERVENTIONS: Participants received droperidol (0.625 or 1.25 mg) or ondansetron 4 mg during general anaesthesia. After discharge from the postanaesthesia care unit presence and severity of akathisia were assessed using the Barnes Akathisia Rating Scale at 4 h postoperatively. MAIN OUTCOME MEASURES: Score of the Global Clinical Assessment of Akathisia of Barnes Akathisia Rating Scale. RESULTS: The number of akathisia observed was 1/118 (0.8%) in the ondansetron group, 1/84 (1.2%) in droperidol 0.625 mg group, and 3/87 (3.4%) in droperidol 1.25 mg group. The akathisia rate difference among the three groups was not significant (P = 0.52). We could not demonstrate significant differences in the incidence of akathisia between the two doses of droperidol. The only case of marked akathisia treated with benzodiazepines was observed after droperidol 1.25 mg. CONCLUSION: The use of droperidol or ondansetron for PONV prophylaxis is associated to a low incidence of akathisia (0.8 to 3.4%) after general anaesthesia for ambulatory surgery. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01942343.