Impact of Timing of Midazolam Administration on Incidence of Postoperative Nausea and Vomiting

No premedication will be given to Patients in the group undergoing a standardized anesthesia protocol which include induction with thiopental (5 mg/kg) and fentanyl (1-2 μg/kg). Atracurium will be used as a muscle relaxant. After tracheal intubation, anesthesia will be maintained with isoflurane in a concentration of 0.8%-1.2%. Ventilation will be adjusted to produce normocapnia. At the end of surgery, reversal of residual neuromuscular blockade will be accomplished using i.v. atropine 20 μg/Kg and neostigmine 40 μg/kg.