Objective To evaluate the therapeutic effects of combined drugs before induction of anaesthesia on myoclonus and other adverse reactions and hemodynamics during etomidate induction. Methods The 120 consenting ASA class Ⅰ or Ⅱ patients(aged 21-65 years) for schedale surgery under general anesthesia were equally randomly into four groups(30 cases each),had no complications of heart,brain and lung systems as well.And Group S1 received sufentanil 0.15μg/kg and midazolam 0.02mg/kg at 3 min before induction,the p...