Effect of Midazolam Premedication on Mask Ventilation Difficulty

Patients of midazolam group will be treated with midazolam premedication (3 cc mixture of 0.1 mg/kg midazolam and normal saline; maximum midazolam dose, 3 mg) intravenously at waiting area 3 minutes before transportation to an operating room. In anesthesia induction, propofol 2 mg/kg will be given.Before the patients were given muscle relaxants, the patients were evaluated with the Han scale.

Control group patients are treated with 3 cc normal saline at waiting area 3 minutes before transportation to an operating room. In anesthesia induction, propofol 2 mg/kg will be given. Before the patients were given muscle relaxants, the patients were evaluated with the Han's grading scale.