Effect of magnesium sulphate on duration and dose requirement of thiopental sodium anesthesia in dogs undergoing experimental enterotomy

摘要

Adult mongrel dog (15) of either sex, 1.8+-0.7-year-old and weighing 15.56+-0.06 kg (mean+-SE) were used in the study to evaluate the effect of pre-and intra-operative administration of magnesium sulphate (MgSO_4) on the duration and dose of thiopental sodium antesthesia undergoing enterotomy. All dogs were premedicated with intramuscular injection of chloropromazine hydrochloride 15 min prior to the injection of 2.5% thiopental sodium in group 1. In group 2, i/v administration of chloropromazine hydrochloride followed by a bolus of 50 mg/kg MgSO_4 (10%) were used before injection of general anaesthesia. In group 3, the dogs received the same anesthetic protocol as in group 2 in addition to i/v infusion of MgSO_4 (10%) @10 mg/kg/hr. Enterotomy modelwas created in all dogs and the mean operation time was 34 min. The results revealed that mean duration of anesthesia was significantly longer in groups 2 and 3 (43.40 and 57.60 min, respectively) as compared to group 1 (38.60 min). The mean total thiopental sodium dose in group 1 (32.10 mg/kg) was significantly greater than those of groups 2 and 3 (26.70 and 20.20 mg/kg respectively). It could be concluded that preoperative and intraoperative administration of MgSO_4 prolong duration of anesthesia, decrease the total dose of thiopental sodium, and facilitate smooth recovery.