Incidence of akathisia after PONV prophylaxis with droperidol or ondansetron in outpatient surgery.  A multicenter controlled randomized trial.

Background and Goal of Study:
Droperidol (DRO) is regularly used for prevention of postoperative nausea and vomiting (PONV)1. Akathisia, a possibly harmful side-effect, is an extra-pyramidal symptom induced by dopamine antagonists, which can lead to readmissions after ambulatory surgery. The aim of this controlled randomized trial is to evaluate the incidence of akathisia after PONV prophylaxis with DRO or ondansetron (OND), in outpatient surgery. 

Materials and Methods:
With local ethics committee approval (CPPEst4) 297 patients with an Apfel score ≥ 2, scheduled to undergo ambulatory surgery, were randomized to receive DRO 0.625 mg, or DRO 1.25 mg or OND 4mg. Barnes’ rating scale2 was used for the global clinical assessment of akathisia (defined by a score ≥ 2). Data were analysed using Bayesian methods. An effect is considered as significant if the probability that the effect exceeds a given threshold is larger than 0.95. Results are expressed as mean or rate and 95% credibility intervals. 

Results and Discussion:
There were no differences for the patients characteristics in the 3 groups. Higher number of women is due to the fact that the female sex is a risk factor in the Apfel score, which was an inclusion criteria. No differences were observed across the 2 DRO groups. Incidence of akathisia was 4/171 in the DRO groups (0.625 and 1.25 mg) and 1/121 in the OND group[tab_01]. The Bayesian estimates rates are 2.7% and 1.4% respectively and Pr(DRO>OND)= 78.2%. Taking account of prior data3 Pr(DRO>OND)= 93.1%. We observed one case of marked akathisa in the DRO 1.25mg group. 
	
Conclusion(s):
Akathisia may be more frequent after DRO when compared with OND prophylaxis for PONV. The use of 1.25mg of DRO can lead to marked akathisia. Better knowledge of akathisia and its objective assessment will allow the anaesthesists to better take this side effect into account.

References: 
1. Schaub I, Lysakowski C, Elia N, et al. EJA. 2012;29:286–294 
2. Barnes, TR. Br. J. Psychiatry J. Ment. Sci. 1989;154:672–676 
3. Timbolschi D, Schaeffer, P. Vidailhet, P,et al. AA. 2009;108: S-15