The Effect of Intravenous Clonidine Pretreatment on Blood Pressure and Heart Rate during General Anesthesia / 대한마취과학회지

Laryngoscopy and endotracheal intubation are potent stimuli that can induce increased sympathetic activity, tachycardia and hypertension. The authors studied the effects of intravenous clonidine pretreatment, a centrally acting a2-adrenoceptor agonist, on hemodynamic responses to laryngoscopy and tracheal intubation, and on anesthetic requirements during operation. Forty ASA I -II patients undergoing elective minor general surgery were allocated randomly to receive either 5ug/kg clonidine or 3 ml of 0.9% normal saline as control intravenously 10 minutes before induction of anesthesia. The results obtained were as follows. Compared to baseline values, blood pressure and heart rate at 1 minute after intubation were significantly increased in control group, but significantly decreased in clonidine group. They were maintained at lower values throughout the whole duration of operation in clonidine group than in control group. More doses of fentanyl were needed in the control group but not in the clonidine group during operation, and because of bradycardia and hypotension, atropine or ephedrine was needed in the clonidine group. In conclusion, the elevation of blood pressure and heart rate accompanying tracheal intubation were preventable with less requirement of supplemental fentanyl, but bradycardia and hypotention were infrequently seen as a side effects, when 5ug/kg intravenous injection of clonidine 10 minutes before induction.

The Effect of Premedication with Intrarectal Ketamine and Midazolam in Children / 대한마취과학회지

The preanesthetic management of preschool children is rather difficult. They worry about separation from their parents, the strange hospital environment, surgery, and are not always amenable to reasoned explanation. Therefore, the preoperative sedation is necessary to reduce anxiety and minimize psychologic trauma to children. To determine which type of intrarectal administration is the most effective in preanesthetic sedation, 90 children were randomly assigned to three groups. Group I was administered with intrarectal midazolam (0.5 mg/kg), group II, intrarectal ketamine (5 mg/kg), and group III, intrarectal midazolam (0.5 mg/kg) with ketamine (5 mg/kg). Most of children separated easily from their parents 30 minutes after intrarectal administration (above 80%). In all groups, the loss of consciousness were below 40% and sedation states were above 80%. But in group III, the loss of consciousness and the sedation states were much better than those of the other two groups. The anxiety level of group III was lower than that of the other groups (p<0.05) and the sedation level of group I and III were better than that of group II (p<0.001). Complications and recovery time were similar among each group. Following intrarectal administration of 0.5 mg/kg of midazolam with 5 mg/kg of ketamine, reliable sedation was obtained 20-30 min after intrarectal administration. Therefore we believe that intrarectal midazolam with ketamine is a useful teehnique for the reliable preoperative sedation in children.