The Effect of Clonidine Premedication and Isoflurane Requirement in Laparoscopic Cholecystectomy Patients
สมชาย เวียงธีรวัฒน์, สมปรารถนา คงธรรม, สุรีรัตน์ ศรีสวัสดิ์*, เมธินี วิทยาโรจน์วงศ์
Department of Anesthesiology, Faculty of Medicine, Ramathibodi Hospital, Bangkok 10400
Sixty patients scheduled for elective laparoscopic cholecystectomy under general anesthesia were randomized into 2 groups. Group I received clonidine 5 *g/kg and group II received midazolam 0.15 mg/kg orally as premedicated drug, 90-120 minutes prior to induction. Anesthesia was induced by thiopental 3-4 mg/kg. Vecuronium 0.1 mg/kg was given to facilitate endotracheal intubation. Maintenance of anesthesia was isoflurane with N2O/O2* The blood pressure and heart rate were kept within *20% of baseline level. The concentration of isoflurane used were recorded at 5,10,15,20,25 and 30 minutes after induction. The results showed that the isoflurane requirement and postoperative sedation score in group I (clonidine group) were significant less than group II (midazolam group) (p<0.002 and <0.004 respectively). We conclude that clonidine reduced the requirement of anesthetic agent by an inhibitory action central nervous system, and locus coeruleus in the brain stem. It also provided better cardiovascular control of blood pressure by decreasing sympathetic outflow and reset baroreceptor reflexes.
วิสัญญีสาร ปี 2542, April-June ปีที่: 25 ฉบับที่ 2 หน้า 85-89