右旋美托咪啶对丙泊酚靶浓度控制输注的有效靶浓度的影响  

Effect of dexmedetomidine on effective target conncentration of target-controlled infusion of propofol

作　　者：莫志伟 

机构地区：[1]广东省高州市中医院麻醉科,高州525200

出　　处：《新医学》2015年第2期102-106,共5页Journal of New Medicine

摘　　要：目的观察不同单次负荷剂量的右旋美托咪啶（DXM）对丙泊酚靶浓度控制输注（TCI）时使患者意识消失的半数有效浓度（EC50）的影响,探讨复合应用两者的安全性。方法选择择期于全身麻醉下行腰椎间盘摘除术的患者80例为研究对象。将患者随机分为D0.25、D0.5、D0.75及D0组各20例,在进行丙泊酚TCI诱导前15 min内采用双盲法分别单次缓慢静脉泵注生理盐水及不同剂量的DXM（0.25、0.5、0.75μg/kg）,丙泊酚起始血浆靶浓度为3.2 mg/L,根据患者意识消失情况采用序贯法决定下一例的丙泊酚TCI血浆靶浓度,各相邻靶浓度之比为1∶1.25。监测给药前、后患者的血压、心电图、心率、脉搏血氧饱和度（Sp O2）等指标。采用加权均数法计算使患者意识消失丙泊酚TCI的EC50及其95%可信区间（95%CI）。记录各组不良反应的发生率。结果 D0组使患者意识消失丙泊酚TCI的EC50为3.02 mg/L,95%CI为2.71-3.39 mg/L;D0.25组的EC50为2.88mg/L、95%CI为2.64--3.15 mg/L;D0.5组的EC50为1.73 mg/L、95%CI为1.57-1.91 mg/L;D0.75组的EC50为1.41 mg/L、95%CI为1.28~1.55 mg/L。4组EC50比较的Z值为13.424,P〈0.01。各组的EC50均明显低于D0组（P〈0.01）,D0.25组至D0.75组的EC50逐渐减小。4组患者均无出现一过性血压升高,心电图及Sp O2均平稳。D0组、D0.25组均无患者出现低血压及心动过缓。D0.5组静脉泵注DXM后1例出现低血压,2例出现心动过缓,使用丙泊酚TCI后2例出现低血压,2例出现心动过缓。D0.75组静脉泵注DXM后5例出现低血压,3例出现心动过缓,使用丙泊酚TCI后5例出现低血压,3例出现心动过缓,D0.5、D0.75的不良反应发生率均高于D0组和D0.25组（P均〈0.008）。结论单次静脉泵注DXM能降低丙泊酚TCI时使患者意识消失的EC50,且随着DXM用量的逐渐增加,EC50也逐渐降低,但低血压和心动过缓等不良反应发生率也随之增加,相对于其它剂量的DXM,0.25μg/kg剂量更安全。Objective To observe the effect of different single loading doses of dexmedetomidine（ DXM） upon half-effective concentration（ EC50） when patients lost consciousness during target-controlled infusion（ TCI） of propofol and discuss the safety of combined application of DXM and propofol. Methods Eighty patients undergoing lumbar diskectomy under general aneasthesia were selected in this study and randomly divided into D0,D0. 25,D0. 5and D0. 75agroups（ n = 20 for each group）. At 15 min before induction of propofol TCI,single intravenous infusion of normal saline and different doses of DXM（ 0. 25,0. 5,0. 75 μg / kg）were conducted using double blind method. Initial target plasma concentration of propofol was 3. 2 mg / L.Based upon the situation of loss of consciousness,the target plasma concentration of propofol TCI was determined by sequential method. The ratio of two consecutive concentrations was 1∶ 1. 25. Blood pressure,electrocardiogram,heart rate and pulse oxygen saturation（ Sp O2） were monitored before and after medicine administration. EC50 and 95% confidence interval（ 95% CI） of propofol TCI when patients lost consciousness were calculated by weighted average method. The incidence of adverse events in all groups was recorded. Results In D0 group,EC50was 3. 02 mg / L and 95% CI was 2. 71-3. 39 mg / L when patients lost consciousness,EC502. 88 mg / L and 95% CI 2. 64-3. 15 mg / L in D0. 25 group,EC501. 73 mg / L and 95% CI 1. 57-1. 91 mg / L in D0. 5group,EC501. 41 mg / L and 95% CI 1. 28-1. 55 mg / L in D0. 75 group. The Z value was 13. 424 when comparing EC50 among four groups（ P 0. 01）. The EC50 in other three groups was significantly lower compared with that in D0group（ all P 0. 01）. The EC50 gradually declined from D0. 25,D0. 5to D0. 75 groups. No transient elevation of blood pressure was observed in all groups and electrocardiogram and Sp O2 were stable. Neither hypotension nor bradycardia was observed in D0 and D0. 25 groups. In D0. 5group,one patient presented with h

关 键 词：右旋美托咪啶 丙泊酚 剂量效应关系 序贯法 

分 类 号：R614[医药卫生—麻醉学]