两种舒芬太尼靶控输注系统的准确性

目的 评价两种舒芬太尼靶控输注系统的准确性.方法 择期手术患者18例,年龄21～64岁,ASA Ⅰ或Ⅱ级,均采用舒芬太尼、异丙酚及维库溴铵行麻醉诱导和维持.随机选择6例患者行体重修正舒芬太尼Gepts药代动力学参数研究,靶控输注舒芬太尼(血浆靶浓度0.8 ng/ml)10 min,输注异丙酚(血浆靶浓度3～4 mg/L),意识消失后静脉注射维库溴铵0.1 mg/kg,靶控输注舒芬太尼(血浆靶浓度0.2～0.8 ng/ml),术毕前30 min停止输注.分别于靶控输注舒芬太尼前、输注舒芬太尼1、3、5、10、20、40、60、90、120和150 min时取桡动脉血3 ml/次,采用ELISA法测定舒芬太尼血药浓度.计算偏离度、准确度,中央室容积(V1)与体重(m)作直线回归分析,并修正药代动力学参数.余12例患者选用上述体重修正后药代动力学参数行临床麻醉,计算舒芬太尼靶控输注系统的偏离度、准确度、分散度、摆动度.结果 采用舒芬太尼Gepts药代动力学参数靶控输注舒芬太尼时,偏离度为16.7%、准确度为42.0%;体重修正后参数为:V1(L)=0.147 m+2.82,K10=0.064 5 min-1、K12=0.108 6 min-1、K21=0.024 5 min-1、K13=0.022 9 min-1、K31=0.001 3 min-1;采用体重修正后药代动力学参数靶控输注舒芬太尼时,偏离度、准确度分别为4.0%、22.3%,较Gepts药代动力学参数靶控输注舒芬太尼时小(P＜0.05),分散度、摆动度分别为-4.4%/h、20.4%.结论 舒芬太尼Gepts药代动力学参数的中央室容积偏大,体重修正后嵌入靶控输注系统,可提高靶控输注的精确度及稳定性,可维持较准确的血药浓度.

Accuracy of target-controlled infusion of sufentanil in clinical anesthesia

Objective To estimate the accuracy of target-controlled infusion (TCI) d sufentanil using the pharmacokinetic parameters proposed by Gepts et al.in clinical anesthesia in Chinese patients.Methods Eighteen ASA Ⅰ or Ⅱ patients aged 21-64 yr undergoing elective surgery under general anesthesia were included in this study.Their body weights were within standard body weight+10%.Radial artery was carmulated before anesthesia for blood sampling.Induction of anesthesia was started with sufentanil TCI.Target plasma concentration (Cp) was set at 0.8 ng/ml.Ten minutes later TCI of propefol was started (Cp=3-4 mg/L).Tracheal intubation was facilitated with vecuronium 0.1 mg/kg as soon as consciousness was lost.Sufentanil TCI was continued at 0.2-0.8 ng/ml (Cp) after induction of anesthesia and terminated at 30 min before the end of surgery.Arterial blood samples were obtained before and at 1,3,5,10,20,40,60,90,120 and 150 rain after sufentanil TCI was started for determination of plasma sufentanil concentration (by ELISA).For each sample the bias,accuracy,divergence and wobble were calculated.Linear regression analysis was performed between volume of central compartment (V1) and body weight (m).The pharmacokinetic parameters proposd by Gepts were modified based on body weight using XLMEM program developed by Minto and Schnider.Another 12 patients received TCI of sufentanil using the modified pharmacokinetic parametem.Results When sufentanil was administered by TCI using original Gepts pharmacokinetic parameters,86 blood samples were measured (the samples obtained before TCI werenot included).PE =-13.7%-75%,bias=16.7%,accuracy=42.0%.After the parameters were modified based on body weight V1(L)=0.147 m+2.82.In the 12 patients when sufentanil was given by TCI using modified Gepts pharmacokinetic parameters 177 blood samples were measured.PE=-30.0%-37.8%;bias=4.0%;accuracy=22.3%;divergence=-4.4%/h and wobble=20.4%,showing a better correlation between the measured and predicted plasma concentration.In general bias＜15%,accuracy＜30% are clinically acceptable.Conclusion V1 of original Gepts pharmacokinetic parameters is too large for Chinese patients.The modified Gepts pbermacokinetic parameters based on body weight suits Chinese patients well.