Effect of Magnesium Sulphate Pretreatment in Pediatric Abdominal Surgery

The patients will be pretreated with magnesium sulphate infusion (30 mg kg-1, total volume 100 ml, infusion rate 5 ml min-1) 20 min. before induction of anesthesia.

Cis-Atracurium will be administered at 0.1-0.15 mg/kg IV bolus for intubation and maintenance at a dose of 0.03 mg/kg iv on fixed intervals.