APD421 given i.v. before surgery is safe and effective at reducing PONV in moderate/high-risk adult surgical patients. The optimal dose tested was 5 mg.

With automated drug administration titrated to comparable BIS, N2O only slightly reduced propofol consumption and did not reduce remifentanil consumption. There was a minor gender dependence, but not by a clinically important amount. Clinical trial registration This study was registered at ClinicalTrials.gov, number NCT00547209.

NCT00779844.