小儿瑞芬太尼靶控输注系统的准确性

目的 评价小儿瑞芬太尼靶控输注(TCI)系统的准确性.方法 择期行五官科或泌尿科手术小儿30例,年龄3～12岁,体重10～40 kg,采用随机数字表法,将患儿随机分为2 ng/ml瑞芬太尼组(Ⅰ组)和4 ng/ml瑞芬太尼组(Ⅱ组),每组15例.Ⅰ组和Ⅱ组采用内嵌Minto药代动力学参数的瑞芬太尼TCI系统输注瑞芬太尼,血浆靶浓度分别为2、4 ng/ml,静脉注射异丙酚2 mg/kg,待患儿意识消失后静脉注射维库溴铵0.1 mg/kg诱导气管插管后行机械通气.两组瑞芬太尼血浆靶浓度维持不变,调节异丙酚输注速率,维持脑电双频谱指数45～65或听觉诱发电位指数＜30,间断静脉注射维库溴铵维持肌松.于TCI瑞芬太尼开始后5、10、20、30、40、50、60 min时抽取桡动脉血样,采用高效液相色谱法测定瑞芬太尼血药浓度,计算TCI系统的偏离度、精确度和摆动度.结果 与血浆靶浓度比较,两组瑞芬太尼实测浓度均升高(P＜0.05);Ⅰ组TCI系统的偏离度、精确度和摆动度分别为20.0%、30.0%和25.0%,Ⅱ组分别为17.5%、17.5%和12.5%,与Ⅰ组比较,Ⅱ组TCI系统的精确度和摆动度降低(P＜0.05),偏离度差异无统计学意义(P＞0.05).结论 3～12岁小儿采用内嵌Minto药代动力学参数的TCI系统输注瑞芬太尼时准确性不高.

Accuracy of remifentanil target-controlled infusion system in children

Objective To evaluate the accuracy of remifentanil target-controlled infusion (TCI) system in children.Methods Thirty ASA Ⅰ patients, aged 3-12 yr, weighing 10-40 kg, scheduled for elective ear-nosethroat or urological surgery, were randomly divided into 2 groups with 15 patients in each group:2 ng/ml remifentanil group (group Ⅰ) and 4 ng/ml remifentanil group (group Ⅱ). Anesthesia was induced with iv injection of propofol 2 mg/kg and TCI of remifentanil. Remifentanil was administered with a specific TCI system incorporating the pharmacokinetic parameters of Minto.The target plasma concentrations of remifentanil were set at 2 or 4 ng/ml. Tracheal intubation was facilitated with vecuronium 0.1 mg/kg after the children lost consciousness. The children were mechanically ventilated.Anesthesia was maintained with TCI of remifentanil, iv infusion of propofol and intermittent iv boluses of vecuronium. The target plasma concentration of remifentanil remained unchanged and bispectral index value was maintained at 45-65 or auditory evoked potentials index value ＜ 30 by adusting the infusion rate of propofol.Arterial blood samples were taken at 5, 10, 20, 30, 40, 50 and 60 min after TCI remifentanil was stared for determination of blood remifentanil concentrations by high performance liquid chromatography. Median prediction performance error (MDPE),median absolute performance error (MDAPE) and wobble of remifentanil TCI system were calculated. Results The measured concentrations of remifentanil were significantly higher than the target plasma concentrations in both groups (P＜0.05). The MDPE, MDAPE and wobble were 20.0% , 30.0% and 25.0% respectively in group Ⅰ , and 17.5%, 17.5% and 12.5% respectively in group Ⅱ . TheMDAPE and wobble were significantly decreased in group Ⅱ compared with group Ⅰ(P＜0.05).Conclusion When remifentanil is administered using a specific TCI system incorporating the pharmacokinetic parameters of Minto in children of 3-12 years old, the accuracy is not high.