The research is to find out whether continuous infusion of rocuronium requires more or less amount of rocuronium, per kilogram and per hour, than bolus administered rocuronium during noncardiac surgery.

comparing the total dose of rocuronium between continuous infusion and intermittent injection

Inclusion Criteria:

• Pediatric patients aged between 2 and 12, undergoing elective noncardiac surgery which requires general anesthesia but does not require intense block, and estimated time of surgery is between 2 and 5 hours

Exclusion Criteria:

• ASA class 3-6
• BMI >= 30
• Previous history of hepatic failure, renal failure or neuromuscular disease
• Patients taking medicine which interacts with rocuronium bromide, before or during surgery: aminoglycosides, lincosamides, acylamino-penicillin antibiotics, tetracyclines, metronidazole (high dose), diuretics, MAO inhibitors, calcium channel blockers, corticosteroids, phenytoin, carbamazepine, or norepinephrine
• Previous history of allergic reaction (including anaphylactic reaction) and/or malignant hyperthermia during general anesthesia
• Patients taking medicines which contains magnesium