不同剂量右美托咪定预防剖宫产术患者脊椎-硬膜外麻醉后寒战的效果

Efficacy of different doses of dexmedetomidine for prevention of shivering after combined spinal-epidural anesthesia in patients undergoing caesarean section

目的 评价不同剂量右美托咪定预防剖宫产术患者脊椎-硬膜外麻醉后寒战的效果.方法 选择脊椎-硬膜外麻醉下行剖宫产术患者120例,ASA分级Ⅰ或Ⅱ级,年龄20 ～ 40岁,体重指数≤35 kg/m2,采用随机数字表法,将其分为4组（n=30）：对照组（C组）和右美托咪定0.1、0.3和0.5 μg/kg组（D1组、D2组和D3组）.于L34间隙行脊椎-硬膜外穿刺,于蛛网膜下腔注入等比重0.5％布比卡因2 ml.于夹闭脐带后D1组、D2组和D3组分别静脉输注右美托咪定0.1、0.3和0.5 μg/kg（溶于50 ml生理盐水中）,C组输注生理盐水50 ml,输注速率均为5 ml/min.记录右美托咪定输注结束后至出PACU期间寒战、心动过缓、低血压和恶心呕吐的发生情况.结果 与C组比较,D2组和D3组寒战发生率、寒战程度和恶心呕吐发生率降低（P＜0.05）,D1组上述各指标差异无统计学意义（P＞0.05）;与D2组比较,D3组寒战发生率、寒战程度和恶心呕吐发生率降低（P＜0.05）.结论 右美托咪定0.3和0.5 μg/kg可预防剖宫产术患者脊椎-硬膜外麻醉后寒战的发生,其中0.5 μg/kg效果更佳.

Objective To evaluate the efficacy of different doses of dexmedetomidine for prevention of shivering after combined spinal-epidural anesthesia in the patients undergoing caesarean section.Methods A total of 120 patients,of ASA physical status Ⅱ or Ⅱ,aged 20-40 yr,with body mass index≤ 35 kg/m2,scheduled for elective caesarean section under combined spinal-epidural anesthesia,were randomly divided into 4 groups （n =30 each） using a random number table：control group （group C） and dexmedetomidine 0.1,0.3 and 0.5 μg/kg groups （D1,D2 and D3 groups）.Combined spinal-epidural anesthesia was performed at L3,4 interspace with isobaric 0.5% bupivacaine 2 ml.In D1,D2 and D3 groups,dexmedetomidine 0.1,0.3 and 0.5 μg/kg （in 50 ml of normal saline） were infused intravenously,respectively.In group C,normal saline 50 ml was infused at a rate of 5 ml/min.The development of shivering,bradycardia,hypotension,nausea and vomiting was recorded during the period from the end of dexmedetomidine infusion to PACU discharge time.Results Compared with group C,the incidence and degree of shivering and incidence of nausea and vomiting were significantly decreased in D2 and D3 groups,and no significant change was found in the parameters mentioned above in group D1.Compared with group D2,the incidence and degree of shivering and incidence of nausea and vomiting were significantly decreased in D3 group.Conclusion Dexmedetomidine 0.3 and 0.5 μg/kg can prevent shivering after combined spinal-epidural anesthesia in the patients undergoing caesarean section,and 0.5 μg/kg provides better efficacy.