不同剂量咪达唑仑与乳化异氟醚对大鼠催眠效应的相互作用

目的 评价不同剂量咪达唑仑与乳化异氟醚对大鼠催眠效应的相互作用.方法 成年雄性SD大鼠125只,体重240～300 g,随机分为5组(n=25),采用改良序贯法进行实验,M组和I组分别经尾静脉注射咪达唑仑、乳化异氟醚,首剂量分别为17.3 mg/kg、0.55 ml/kg;MI1组、MI2组和MI3组分别经尾静脉注射1/4、1/2、3/4咪达唑仑催眠效应半数有效剂量(ED50)+乳化异氟醚(首剂量分别为0.22、0.19、0.12 ml/kg),各组相邻剂量比值均为0.85,采用改良序贯法计算各组咪达唑仑、乳化异氟醚催眠效应的ED50,及其95%可信区间(95%CI).催眠有效的标准:前爪翻正反射消失.采用等辐射分析法判断不同剂量咪达唑仑与乳化异氟醚催眠效应的相互作用.结果 M组咪达唑仑催眠效应的ED50及其95%CI为26(22～30)mg/kg;I组、MI1组、MI2组及MI3组乳化异氟醚催眠效应的ED50及其95%CI分别为0.67(0.61～0.73)、0.30(0.28～0.33)、0.22(0.18～0.26)、0.18(0.16～0.20)ml/kg.MI1,组、MI1组、MI3组两药相互作用系数分别为1.51(P<0.01)、1.21(P<0.05)、0.98(P0.05).结论 咪达唑仑6.5、13 mg/kg复合乳化异氟醚时两药的催眠效应为协同作用,咪达唑仑19.5 mg/kg复合乳化异氟醚时两药的催眠效应为相加作用.     

等辐射分析法研究全身麻醉诱导丙泊酚、依托咪酯催眠相互作用

目的以等辐射分析法研究全身麻醉诱导时丙泊酚、依托咪酯催眠效应相互作用。方法75例择期上腹部手术病人随机分成三组:丙泊酚(P)组、依托咪酯(E)组、丙泊酚复合依托咪酯(C)组,每组25例。再各分成5个亚组(P1~P5,E1~E5,C1~C5)。麻醉诱导前各亚组给予不同剂量的丙泊酚及依托咪酯。监测给药前、给药后1、2、3、5min的SBP、DBP、HR、SpO2等指标。病人对口令失去反应即进入催眠状态。给药2min后,开始评估。以等辐射分析法分析两者之间催眠相互作用。结果在催眠末点:P组ED50值为1.15mg/kg(95%可信限0.95~1.40);E组ED50值为0.11mg/kg(95%可信限0.09~0.13);C组ED50值分别为0.38/0.05mg/kg(95%可信限0.33/0.05~0.44/0.06)。在催眠末点,C组ED50偏离相加线有显著性差异(P<0.05)。C组的SBP、DBP在给药前后无显著性差异(P>0.05)。结论点斜法测定依托咪酯ED50值为0.11mg/kg;经等辐射分析法分析后判定丙泊酚、依托咪酯(剂量比7/1)在催眠效应上呈现协同作用,复合用药血液动力学稳定。     

瑞马唑仑复合阿芬太尼用于无痛胃镜检查的半数有效量

目的测定瑞马唑仑复合阿芬太尼用于无痛胃镜检查的ED50及95%有效量(95% effective dose, ED95)。方法选择行胃镜检查的患者60例, 按年龄分为青年组(Y组, 年龄18～44岁)和中年组(M组, 年龄45～60岁), 每组30例。所有患者静脉推注阿芬太尼5 μg/kg, 30 s后推注瑞马唑仑, 初始剂量为0.1 mg/kg, 改良警觉/镇静评分(modified Observer’’s Assessment of Alertness/Sedation, mOAA/S)<3分时进行胃镜检查。按照改良序贯法进行试验, 根据胃镜检查的镇静效果, 确定下一位患者的瑞马唑仑剂量。患者镇静"成功", 则下一例患者瑞马唑仑剂量降低0.03 mg/kg, 否则增加0.03 mg/kg。记录患者瑞马唑仑用量、胃镜检查时间、苏醒时间、术中知晓及不良反应发生情况, 采用概率单位回归法计算瑞马唑仑的ED50、ED95及其95%CI。结果 Y组的ED50为0.13(0.11～0.16)mg/kg, ED95为0.19(0.16～0.33)mg/kg;M组的ED50为0.09(0.0...     

序贯试验法测定苯磺酸瑞马唑仑在女性患者致意识消失的半数有效量

目的测定苯磺酸瑞马唑仑(瑞马唑仑)在女性患者致意识消失的ED50。方法选择择期拟在全凭静脉麻醉下行宫腔镜检查的妇科患者32例, ASA分级Ⅰ、Ⅱ级, 年龄35～55岁。麻醉诱导时应用序贯试验法给予0.10、0.13、0.16、0.20、0.25 mg/kg五种剂量之一的瑞马唑仑, 采用Probit回归分析计算瑞马唑仑在女性患者致意识消失的ED50和95%有效量(95% effective dose, ED95)以及各自的95%CI。结果瑞马唑仑在女性患者致意识消失的ED50为0.175 mg/kg(95%CI 0.153～0.206 mg/kg), ED95为0.255 mg/kg(95%CI 0.213～0.577 mg/kg)。瑞马唑仑给药前后患者呼吸循环平稳, 其中两例患者在给药后出现呃逆现象。结论序贯试验法测定瑞马唑仑在女性患者致意识消失的ED50为0.175 mg/kg。     

经皮穴位电刺激对咪达唑仑致老年患者意识消失半数有效量的影响

目的：探讨经皮穴位电刺激对咪达唑仑致老年患者意识消失半数有效量（ED50）的影响。方法：选择在我院择期椎管内麻醉行骨科下肢手术老年患者 52 例,随机将患者分为 2 组：经皮穴位电刺激组和对照组。实施椎管内麻醉,刺激组选择双侧合谷穴、内关穴给予经皮穴位电刺激 20 min 后静脉注射咪达唑仑。对照组患者在相应穴位贴电极片,并连接刺激器,不予电刺激。以 OAA/S 评分≤ 2 分判定为意识消失。采用序贯法确定咪达唑仑剂量,初始剂量为 40 μg/kg,相邻剂量比为 1∶1.1。当出现 7 次阴阳交叉时终止试验。采用序贯法公式法计算咪达唑仑致患者意识消失 ED50 及其 95% 置信区间。结果：刺激组咪达唑仑致患者意识消失 ED50 及其 95% 置信区间为 40.5 μg/kg（95% CI 为 28.1~58.2 μg/kg）,对照组为 47.7 μg/kg（95% CI 为 33.1~68.9 μg/kg）,两组比较差异有统计学意义（P<0.05）。结论：经皮穴位电刺激可降低咪达唑仑致老年患者意识消失的 ED50。     

瑞马唑仑和丙泊酚用于宫腔镜检查术镇静效应的相互作用

目的评价瑞马唑仑和丙泊酚用于宫腔镜检查术镇静效应的相互作用。方法拟行宫腔镜检查术患者, 年龄20～45岁, BMI 18～28 kg/m2, ASA分级Ⅰ或Ⅱ级, 试验分两步进行, 用序贯法确定A组(瑞马唑仑)和B组(丙泊酚)的半数有效剂量(ED50);以A组和B组获得的ED50为标准确定C组(0.25×瑞马唑仑ED50+0.75×丙泊酚ED50为起始剂量)、D组(0.5×瑞马唑仑ED50+0.5×丙泊酚ED50为起始剂量)和E组(0.75×瑞马唑仑ED50+0.25×丙泊酚ED50为起始剂量)复合用药方案, 用序贯法确定C组、D组和E组丙泊酚和瑞马唑仑复合用药时丙泊酚的ED50。采用等辐射分析法分析两药镇静效应的相互作用, 计算相互作用系数及两者协同作用剂量配比。结果 A组瑞马唑仑ED50为0.180 mg/kg, B组丙泊酚ED50为1.167 mg/kg, 等辐射分析结果显示, 瑞马唑仑和丙泊酚具有协同作用, 当瑞马唑仑0.045、0.090、0.135 mg/kg与丙泊酚0.546、0.288、0.160 mg/kg复合使用时, 相互作用系数分别为:1.393、1.339、1....     

全身麻醉诱导时咪唑安定与氯胺酮催眠相互作用的研究

目的 以等辐射分析法研究全身麻醉诱导时咪唑安定与氯胺酮之间催眠相互作用.方法 将90例择期上腹部手术患者随机分为:咪唑安定组(M组)、氯胺酮组(K组)、咪唑安定与氯胺酮复合组(C组),每组30例.麻醉诱导前各组以序贯方式给予不同剂量的咪唑安定、氯胺酮及两药复合药物(咪唑安定与氯胺酮剂量的数值比为1:10),给药2 min后开始催眠末点评估,患者对言语指令失去反应即进入催眠末点,对已进入催眠状态的患者进行麻醉末点评估,以序贯法测定三组催眠、麻醉末点半数有效剂量(ED50),以等辐射分析法分析两者之间催眠、麻醉相互作用.结果 在催眠末点:M组ED50为0.18 mg/kg(95%CI 0.09～0.31 mg/kg);K组ED50为0.50 nag/kg(95%CI 0.38～0.61 mg/kg);C组ED50为0.038/0.38 mg/kg(95%CI 0.024/0.24～0.073/0.73mg/kg),在催眠末点,C组ED50偏离相加线无统计学意义.结论 经等辐射分析法证实,咪唑安定与氯胺酮催眠效应上呈现相加作用.     

点斜法、序贯法测定全身麻醉诱导时依托咪酯催眠ED50的研究

目的测定全身麻醉诱导时依托咪酯催眠效应半数有效量(ED50),比较点斜法、序贯法测定ED50的利弊。方法25例择期手术病人(点斜法)随机分配到5个不同剂量组,麻醉诱导前给予不同剂量的依托咪酯。14例择期手术病人(序贯法)依次给予一定剂量的依托咪酯。监测给药前、给药后1、2、3、5min的SBP、DBP、HR、SpO2等指标。病人对口令失去反应即进入催眠状态,两组均给药后2min开始评估。以点斜法、序贯法分别计算依托咪酯催眠效应ED50。结果点斜法测定的依托咪酯催眠效应ED50为0·112mg/kg(95%可信限0·094~0·134mg/kg);序贯法测定的为0·120mg/kg(95%可信限0·101~0·143mg/kg)。给药前与给药后1、2、3、5min的SBP、DBP、HR、SpO2等指标比较差异均有显著意义(P<0·05)。结论依托咪酯催眠效应ED50为0·112mg/kg(点斜法)或0·120mg/kg(序贯法)。两种方法均能用于测定ED50。     

依托咪酯与雷米芬太尼在全身麻醉诱导时的相互作用

目的用等辐射分析法研究全身麻醉诱导时依托咪酯、雷米芬太尼之间的相互作用。方法择期腹部手术患者75例随机均分为依托咪酯组(E组)、雷米芬太尼组(R组)和复合组(ER组)。各组再分成5个亚组(E1～E5、R1～R5、ER1～ER5组)。麻醉诱导前给药,E1～E5组分别给予依托咪酯0.040、0.060、0.085、0.115、0.155 mg/kg,R1～R5组分别给予雷米芬太尼5.400、7.105、8.850、11.200、15.540μg/kg,ER1～ER5组分别给予依托咪酯及雷米芬太尼0.021 mg/kg+2.600μg/kg、0.030 mg/kg+3.500μg/kg、0.045 mg/kg+4.200μg/kg、0.060 mg/kg+5.500μg/kg、0.080 mg/kg+7.600μg/kg。监测给药前(T1)及给药后1min(T2)、2min(T3)、3min(T4)、5 min(T5)的SBP、DBP、HR、SpO2、听觉诱发电位指数(AAI)的变化。口令法判断患者是否进入催眠状态。点斜法计算各自药物催眠末点的半数有效量(ED50)及复合后两种药物的ED50,以等辐射分析法分析两药在催眠末点的相互作用。结果在催眠末点,依托咪酯ED50为0.084 mg/kg(95%可信限0.070～0.103μg/kg);雷米芬太尼ED50为8.100μg/kg(95%可信限7.901～8.435μg/kg);ER组依托咪酯和雷米芬太尼ED50分别为0.038 mg/kg和3.900μg/kg(95%可信限0.032～0.043μg/kg和3.760～4.200μg/kg)。两药在催眠作用上呈现相加。E1～E5组、R1～R5组、ER1～ER5组给药前后血流动力学变化无统计学意义。E4、ER4组T3、T4时、E5组T2、T3时、ER5组T2～T4时AAI显著低于T1时(P0.05)。结论依托咪酯、雷米芬太尼两药在催眠作用上呈现相加,复合用药血流动力学稳定。     

不同性别患者预注顺阿曲库铵加快起效的半数有效剂量

目的 探讨不同性别患者预注顺阿曲库铵加快起效的半数有效剂量(ED50).方法 择期拟在全身麻醉下行腹部手术的患者90例,年龄18～55岁,分为2组(n=45):男性组(M组)和女性组(F组).采用TOF-Watch SX型加速度肌松监测仪对尺神经行单次颤搐刺激,监测拇内收肌肌颤搐情况.静脉注射咪达唑仑0.04 mg/kg、芬太尼1 μg/kg,患者意识消失后开启加速度肌松监测仪,静脉注射顺阿曲库铵预注剂量,3 min后静脉注射芬太尼5 μg/kg、异丙酚2 mg/kg,静脉注射预注量后4 min,静脉注射顺阿曲库铵剩余插管剂量(3×ED95即0.15 mg/kg减去预注量),当单刺激颤搐值与对照值的比值下降至10%,行气管插管.静脉输注异丙酚、瑞芬太尼,吸入异氟烷维持麻醉.预注量根据序贯法确定,预注量从5μg/kg(10%ED95)开始,各相邻剂量比值为1.2.记录给予预注量后4min时单刺激颤搐值与对照值的比值、90%起效时间、起效时间、最大阻滞程度、临床作用时间.计算预注顺阿曲库铵加快起效的ED50及其95%可信区间(CI).结果 M组90%起效时间长于F组(P＜0.05),其余肌松效应指标两组比较差异无统计学意义(P＞0.05).预注顺阿曲库铵加快起效的ED50:男性为21.36μg/kg,95%CI为20.52～22.23μg/kg;女性为14.53 μg/kg,95%CI为13.77～15.33μg/kg,男性高于女性(P＜0.05).结论 预注顺阿曲库铵加快起效的ED50:男性为21.36μg/kg,女性为14.53 μg/kg,男性高于女性.     

Midazolam premedication reduces propofol dose requirements for multiple anesthetic endpoints

PURPOSE: This study investigates the interactions between midazolam premedication and propofol infusion induction of anesthesia for multiple anesthetic endpoints including: loss of verbal contact (LVC; hypnotic), dropping an infusion flex (DF; motor), loss of reaction to painful stimulation (LRP; antinociceptive) and attainment of electroencephalographic burst suppression (BUR; EEG). METHODS: In a double blind, controlled, randomized and prospective study, 24 ASA I-II patients received either midazolam 0.05 mg x kg(-1) (PM; n = 13) or saline placebo (PO; n = 11) i.v. as premedication. Twenty minutes later, anesthesia was induced by propofol infusion at 30 mg x kg(-1) x hr(-1). ED50, ED95 and group medians for times and doses were determined and compared at multiple anesthetic endpoints. RESULTS: At the hypnotic, motor and EEG endpoints, midazolam premedication significantly and similarly reduced propofol ED50 (reduction: 18%, 13% and 20% respectively; P <0.05 vs unpremedicated patients) and ED95 (reduction: 20%, 11% and 20% respectively; P <0.05 vs unpremedicated patients). For antinociception (LRP), dose reduction by premedication was greater for propofol ED95 (reduction: 41%; P <0.05 vs unpremedicated patients) than ED50 (reduction: 18%; P <0.05 vs unpremedicated patients). Hemodynamic values were similar in both groups at the various endpoints. CONCLUSIONS: Midazolam premedication 20 min prior to induction of anesthesia reduces the propofol doses necessary to attain the multiple anesthetic endpoints studied without affecting hemodynamics in this otherwise healthy population. The interaction differs for different anesthetic endpoints (e.g., antinociception vs hypnosis) and propofol doses (e.g., ED50 vs ED95).     

A small dose of midazolam decreases the time to achieve hypnosis without delaying emergence during short-term propofol anesthesia.

STUDY OBJECTIVE: To evaluate the effect of a small dose of midazolam (10 microg kg(-1)) on induction and emergence during short-term propofol anesthesia and to investigate the effects of subsequent administration of flumazenil. DESIGN: Double-blinded, prospective, randomized study. SETTING: Operating room of a medical college hospital. PATIENTS: 30 male ASA physical status I and II patients (ages 51 to 75) scheduled for minor surgery under spinal anesthesia. INTERVENTIONS: Patients were randomly allocated to one of three groups: the placebo-propofol-placebo (PP) group, the midazolam-propofol-placebo (MP) group, or the midazolam-propofol-flumazenil (MF) group. After administering placebo or midazolam (10 microg kg(-1)), propofol 250 microg kg(-1) min(-1) was infused. Immediately after confirming that the patient was hypnotized, we terminated the propofol infusion and administered placebo or flumazenil (5 microg kg(-1)). MEASUREMENTS: The dose and the times required to achieve hypnosis (the first endpoint) and to emerge from anesthesia (the second endpoint). The plasma concentration at each endpoint was determined. MAIN RESULTS: Midazolam significantly decreased the dose and time needed to achieve hypnosis [PP vs. MP, 66 +/- 14 vs. 48 +/- 15 mg, 260 +/- 55 vs. 179 +/- 44 sec, respectively (mean +/- SD)]. Thus, the plasma concentration of propofol at hypnosis was significantly lower (PP vs. MP, 3.31 +/- 0.78 vs. 2.41 +/- 0.57 microg mL(-1)). The time to emerge from anesthesia was not prolonged by midazolam, and was further shortened by administration of flumazenil (PP, MP vs. MF, 237 +/- 77, 207 +/- 71 s vs. 126 +/- 56 sec, respectively). Flumazenil also reversed the reduction in propofol concentration induced by midazolam at emergence (PP, MP, and MF, 0.54 +/- 0.17, 0.37 +/- 0.15, and 0.59 +/- 0.22 microg mL(-1), respectively). CONCLUSIONS: Coadministration of 10 microg kg(-1)midazolam decreases the dose and time required to achieve hypnosis with propofol induction without delaying emergence from anesthesia. Additional administration of flumazenil further shortens the time to emerge from midazolam-propofol anesthesia.     

肝硬化对大鼠异丙酚镇静效力的影响

目的 探讨肝硬化对大鼠异丙酚镇静效力的影响.方法 健康雄性SD大鼠58只,体重180～220 g,随机分为3组,正常对照组(C组,n=18)、轻度肝硬化组(M1组,n=20)和重度肝硬化组(M2组,n=20).M1组和M2组采用四因素法制备大鼠轻度肝硬化和重度肝硬化模型.模型制备成功后,静脉注射异丙酚,第1只大鼠的剂量为5.912 mg/kg,应用序贯法确定下一只大鼠的剂量,相邻剂量比为0.85,以翻正反射消失作为判断异丙酚镇静起效的标准.采用序贯法计算异丙酚镇静效应的半数有效剂量(ED50).结果 与C组比较,M1组及M2组异丙酚镇静效应的ED50降低(P＜0.05或0.01);与M1组比较,M2组异丙酚镇静效应的ED50降低(P＜0.05).结论 肝硬化可强化大鼠异丙酚的镇静效力.     

High-dose flumazenil potentiates the hypnotic activity of propofol, but not that of thiopental, in ddY mice

BACKGROUND: Flumazenil is a specific benzodiazepine agonist, which is reported to have a partial benzodiazepine agonist-like effect at a high dose. This study investigated the effects of flumazenil and midazolam on the hypnotic dose of propofol and thiopental in ddY mice, using a behavioral model. METHODS: Mice were given either propofol or thiopental intravenously to induce hypnosis, which was defined as a loss of the righting reflex. The mice were pre-treated with flumazenil (0.05, 0.1, or 0.2 mg kg(-1)) or midazolam (0.1 or 0.2 mg kg(-1)), and given propofol or thiopental after a 30-s delay. RESULTS: Pre-treatment with flumazenil (0.1 or 0.2 mg kg(-1)) significantly decreased the hypnotic dose of propofol compared to the control group (9.3+/-0.39 [8.5-10.0] or 9.0+/-0.28 [8.5-9.6] vs. 10.8+/-0.42 [9.9-11.6] mg kg(-1) (ED50+/-SEM and [95% confidence interval]) P<0.05), but not that of thiopental (9.1+/-0.30 [8.5-9.7] with 0.2 mg kg(-1) flumazenil vs. 9.3+/-0.42 [8.4-10.1] mg kg(-1) with saline). Midazolam reduced the hypnotic dose of both propofol and thiopental. Flumazenil antagonized the potentiating effect of midazolam (0.2 mg kg(-1)) on the hypnotic activity of propofol. CONCLUSIONS: These results suggest that the hypnotic activity of propofol is potentiated by the partial agonist activity of flumazenil in ddY mice.     

咪唑安定与丙泊酚对脑电双频指数的影响

目的测定和比较咪唑安定与丙泊酚诱导时半数病人入睡时的脑电双频指数（BIS50）和半数有效量（ED50）。方法选择60例无服用精神药物和镇静催眠药物史、无术前用药的门诊手术病人（ASAⅠ～Ⅱ级），随机均分为咪唑安定组（M组）和丙泊酚组（P组），以半数效量序贯法分别进行咪唑安定与丙泊酚诱导的睡眠观察，以对语言指令和睫毛反射消失为入睡指标，同时记录BIS的变化。对取得的数据以直线回归的方法和加权均数法分别求得咪唑安定、丙泊酚的BIS50和ED50。结果咪唑安定诱导后，术峤病人与入睡病人的BIS值均较用药前的基础值明显下降，但下降幅度在两类病人之间差异无统计学意义，BISso和EDso分别为：77．02（95％可信区间为：71．08～85．86）和0．1237mg／kg（95％可信区间为：0．0990-0．1540mg／kg）。丙泊酚诱导时未睡病人的BIS值下降不明显，而入睡病人的BIS值显著下降，两者之间差异有统计学意义（P〈0．05）。丙泊酚的BIS50和ED50分别是79．17（95％可信区间为：72．08～88．55）和1．0192mg／kg（95％可信区间为：0．9400～1．1480mg／kg）。结论咪唑安定和丙泊酚对BIS的影响有较大的差异。与丙泊酚比较，BIS值与咪唑安定催眠效果的相关性小于丙泊酚。     

Timing of midazolam and propofol administration for co-induction of anaesthesia

We aimed to determine the optimum timing of midazolam administration prior to propofol to achieve the maximal reduction in the dose of propofol required to induce anaesthesia. Female (ASA 1-2) patients, aged 18 to 45 years, weighing 40 to 75 kg and scheduled for gynaecological surgery were eligible for the study. Consenting patients were randomly assigned to six groups. Group 1 received saline and Groups 2 to 6 received midazolam 3 mg at 1, 2, 4, 6 or 10 minutes respectively prior to propofol (n = 20 to 22 per group) in a blinded manner. Propofol was administered i.v. over 10 seconds and flushed in with saline 5 ml. Two minutes later, the patient's response to pressure applied to the finger was determined as an index of loss of consciousness. The ED50 of propofol in each group was determined by the up-and-down method. Propofol ED50 was reduced to 34 to 67% (P < 0.001) in the midazolam treated groups. There was no significant (P = 0.14) difference in propofol ED50 among the five groups which received midazolam. Patients who received midazolam had less recollection of events surrounding induction (P < 0.001) and recalled the induction experience as being more pleasant (P = 0.03) than those who did not receive midazolam. These results indicate that midazolam may be given up to 10 minutes prior to propofol and still achieve a substantial dose reduction.     

静脉麻醉药抑制利多卡因致大鼠惊厥作用的比较

目的比较静脉麻醉药丙泊酚、依托咪酯、咪达唑仑及硫喷妥钠拮抗利多卡因致大鼠惊厥的作用。方法雄性Wistar大鼠36只,体重(250±20)g,随机均分为六组:空白对照组(C组)、利多卡因组(L组:利多卡因4mg·kg-1·min-1)、利多卡因+丙泊酚组(P组:利多卡因+丙泊酚12.5mg/kg)、利多卡因+依托咪酯组(E组:利多卡因+依托咪酯1.85mg/kg)、利多卡因+咪达唑仑组(M组:利多卡因+咪达唑仑0.65mg/kg)和利多卡因+硫喷妥钠组(T组:利多卡因+硫喷妥钠30.85mg/kg),惊厥后2h处死大鼠,取出脑组织分离双侧海马,一侧用于检测c-fos阳性细胞蛋白的表达。另一侧用于测定一氧化氮(NO)含量及一氧化氮合酶(NOS)活性。结果除C组外,其它五组大鼠均出现了惊厥,给予静脉麻醉药抑制惊厥,五组惊厥持续时间差异无统计学意义。L、P、E、M和T组c-fos阳性细胞表达、NO含量和NOS活性显著高于C组(P<0.05);P、E、M和T组c-fos阳性细胞表达、NO含量及NOS活性均显著降低于L组(P<0.05);M、T组c-fos阳性细胞表达、NO含量及NOS活性显著低于P、E组(P<0.05)。结论静脉麻醉药咪达唑仑、丙泊酚、依托咪酯及硫喷妥钠均可有效抑制利多卡因致惊厥作用,其中咪达唑仑与硫喷妥钠效果更显著。     

Midazolam premedication reduces propofol requirements for sedation during regional anesthesia

PURPOSE: Propofol is often used for sedation during spinal anesthesia. We investigated the effects of midazolam premedication on the propofol requirements and incidence of complications during sedation. METHODS: In a prospective randomized, controlled, and single-blinded study, 50 patients undergoing elective gynecological surgery were randomly divided into control and midazolam groups. Patients in the midazolam group received 2 mg midazolam im 30 min before arrival at the operation room. After spinal anesthesia was instituted with intrathecal injection of hyperbaric tetracaine, we provided sedation using continuous infusion of propofol. The level of sedation was controlled at a level between "eyes closed but rousable to command" and "eyes closed but rousable to mild physical stimulation" by adjusting the infusion rate. During sedation, the propofol requirements and complications were recorded and patients were asked, two hours after the end of operation, whether they remembered intraoperative events. RESULTS: In the midazolam group, the loading dose, steady state infusion rate, and overall infusion rate of propofol were 0.74 mg x kg(-1), 2.86 mg x kg(-1) x hr(-1), and 3.32 mg x kg(-1) x hr(-1), respectively, which were about 17% lower than those in the control group (P<0.05). Moreover, midazolam premedication reduced the incidence of intraoperative memory (P < 0.05), but had no effects on other complications. CONCLUSION: Midazolam premedication reduced propofol requirements and the incidence of intraoperative memory during sedation. These effects on sedation using propofol during spinal anesthesia are considered beneficial for patients.