Methods
agitation, pain
A total of 70 patients were randomly assigned to two groups: the Magnesium group (M group) and the control group (C group). After a routine intravenous anesthetic induction, patients in the M group received a 30 mg/kg bolus of intravenous magnesium during the first hour and then a continuous infusion of 10 mg/kg ×h until the end of the surgery, patients in the C group received 0.9% saline at the same volume and rate. The sedation-agitation scale (SAS) and the visual analogue scale were used to assess agitation and pain, respectively.