瑞芬太尼小儿麻醉对体动反应和呼吸抑制的半数有效剂量

目的观察瑞芬太尼麻醉对小儿外科手术体动反应和呼吸抑制的半数有效剂量。方法 60例小儿外科短小手术病例,随机分为两组,每组30例,Ⅰ组观察静脉注射瑞芬太尼后小儿体动反应情况,Ⅱ组则观察注射瑞芬太尼后小儿的呼吸抑制情况。静注氯胺酮2mg/kg,异丙酚1-2mg/kg,单纯面罩或插入喉罩吸氧2-3L/min,吸入2%七氟醚维持麻醉,术中维持自主呼吸。切皮前静脉给予瑞芬太尼,剂量根据Dixon序贯法确定。结果瑞芬太尼消除切皮时体动反应的50%有效剂量为0.41μg/kg（95%可信区间为0.23-0.48μg/kg）,引起呼吸抑制反应的50%有效剂量为0.67μg/kg（95%可信区间为0.48-0.81μg/kg）。结论瑞芬太尼引起切皮时无体动反应的50%有效剂量为0.41μg.kg-1,引起呼吸抑制反应的50%有效剂量为0.67μg.kg-1,临床上应选择以上剂量以下以避免麻醉中的呼吸抑制。

ED(50)s of remifentanil in sevoflurane anesthesia to blunt movement and spontaneous respiratory in pediatric surgery

Objective To investigate the ED（50）s of remifentanil in sevoflurane anesthesia to blunt movement and respiratory in pediatric surgery.Methods 60 paediatric patients for short-time surgery were recruited and divided into two groups,GroupⅠ（n=30）were observed for body moving response to surgery after injection of remifentanil and GroupⅡ（n=30）for patients＇ respiratory depression after injection of remifentanil.Both groups were injected ketamine 2 mg·kg-1 in veinous before entering operating room,followed by propofol 1-2 mg·kg-1,then were oxygened by mask or laryngeal mask.Anesthesia were maintained by inhaling 2% sevoflurane and keep spontaneous ventilating.Before the beginning of surgery,remifentanil was injected over 10 s.The bolus dose of remifentanil was determined by Dixon＇s method,increasing or reducing the bolus dose of remifentanil（0.1 μg·kg-1 as a step size）was determined by the previous patient＇s body moving response to surgery or respiratory depression.Results The bolus dose of remifentanil at which there was a 50% probability of no movement [ED（50）] to surgery was 0.41μg·kg-1,（95% confidence limits,0.23-0.48 μg·kg-1）and ED（50）to respiratory depression was 0.67 μg·kg-1（95% confidence limits,0.48-0.81 μg·kg-1）.Conclusion ED（50）of remifentanil in sevoflurane anesthesia to blunt movement and respiratory in pediatric surgery was 0.41 μg·kg-1 and 0.67 μg·kg-1 respectively,which means respiratory depression would follow the injection of remifentanil to blunt the children movement in surgery.