摘要：
Objective To explore the effect of general anesthesia on Wuzhishan miniature pigs induced by a mixture of ketamine, Sumianxin II and midazolam, and maintained by ketamine and propofol in surgery lasting up to 8 hours. Methods A total of 18 Wuzhishan miniature pigs (body weight (20. 3 ± 1. 9) kg, 14 male and 4 female) were used in this study. The induction of anesthesia was performed with intramuscular injection of ketamine (8 -10 mg/kg) Sumianxin II (1. 5 mL) and midazolam (10 mg) behind the ear, and the general anesthesia was maintained with a mixture containing 0. 9％ sodium chloride 8 mL, ketamine 100 mg/2 mL and propofol 200 mg/40 mL, continuously injected through the marginal ear vein through a syringe infusion pump. The time spent for anesthesia induction and the duration time of anesthesia were recorded. Physiological indexes including body temperature, blood pressure, heart rate and respiratory rate, the reflex activities, and the effects of analgesia, sedation and muscular relaxation of the miniature pigs under anesthesia at 0, 0. 5, 1, 1. 5, 2, 4, 6, 8 h were observed. Results All the 18 pigs were successfully anaesthetized, but 4 pigs died during surgery due to hypovolemic shock, anesthesia accident, left main coronary thrombosis and reperfusion arrhythmia, respectively. During anesthesia, the analgesia, sedation and muscular relaxation effects on the pigs were obvious. The average time spent for anesthesia induction was (4. 8 ± 1. 2) min and the duration time of anesthesia was (54. 1 ± 5. 8) min. The eyelid reflex, corneal reflex and anal reflex in the pigs were weak or disappeared during 1 -8 h after the anesthesia was induced. The body temperature of the pigs was decreased gradually, with a significant difference between 1 h and 0 h (P＜ 0. 05), reaching the lowest point at 4 h, and then maintained stable. The blood pressure was gradually decreased, reaching the lowest level at 2 h (P ＜ 0. 05), then somehow increased, and maintained at a stable level until the end of surgery. The respiratory rate fluctuated during the anesthesia, with no significant difference. Conclusions The anesthesia induced by a combination of ketamine, Sumianxin II and midazolam and maintained with a combination of ketamine and propofol is simple to operate, shows effects fast, and has good effects of analgesia, sedation and muscular relaxation, keeping the circulatory system and respiratory system relatively stable throughout the anesthesia. Thus it is suitable for general anesthesia for miniature pigs.%目的 观察氯胺酮、速眠新II和咪达唑仑混合液诱导麻醉,氯胺酮和丙泊酚维持麻醉对实验时间长达8 h的五指山小型猪的全身麻醉效果.方法 18头体重 (20. 3 ± 1. 9) kg的五 指山小型猪采用联合氯胺酮、速眠新II和咪达唑仑耳后肌肉注射诱导麻醉成功后,氯胺酮与丙泊酚混合液静脉持续泵入,观察诱导药物的起效时间和持续时间,以及小型猪进入麻醉状态后0、0. 5、1、 1. 5、2、4、6、8 h的体温、血压、心率和呼吸等生理指标、反射活动和镇痛镇静肌松效果.结果 18头成功麻醉,4头术中死亡,原因分别为低血容量性休克、麻醉意外、左主干血栓和再灌注心律失常.麻醉全程中猪的镇痛、镇静、肌松效果显著,平均显效时间为 (4. 8 ± 1. 2) min,维持时间为 (54. 1 ± 5. 8) min.1～8 h间,小型猪的眼睑反射、角膜反射和肛门反射均迟钝或消失; 麻醉全程 体温均呈下降趋势,麻醉后1h体温较0h差异有显著性(P＜ 0. 05),4h降至最低点后维持稳定.血压逐步下降,因球囊阻断前降支血流诱发心肌梗死致使血压在2 h降至最低,2 h与0 h相比差异有显著性 ( P＜ 0. 05).球囊撤出后,血压和心率回升至相对稳定水平.呼吸虽有波动,但差异无显著性.结论 氯胺酮、速眠新Ⅱ和咪达唑仑复合诱导麻醉,氯胺酮和丙泊酚联合维持麻醉方案具有操作简单、起 效快,麻醉全程中循环系统和呼吸系统相对稳定,并且镇痛镇静肌松效果良好等优点,适合小型猪的全身麻醉.
