右美托咪定预注对瓣膜置换术患者麻醉诱导期血流动力学和脑电双频指数的影响

目的观察新型肾上腺素受体激动剂右美托咪定（dexmedetomi（iine,Dex）预注对瓣膜置换术患者麻醉诱导期血流动力学和脑电双频指数（bispectralindex,BIS）值的影响。方法选择择期瓣膜置换术患者30例,采用随机数字表法分为两组：Dex组（D组）和对照组（C组）,每组15例。D组于麻醉诱导前静脉微量泵预注用生理盐水稀释成50ml的Dex（浓度为4mg／L）0．5μg／kg,输注时间为10min,C组以同样方式输注等体积生理盐水。均以依托咪脂、芬太尼、哌库溴铵、咪达唑仑复合诱导麻醉。记录入室后输注Dex前即刻基础值（T1）、输注Dex后5min（T2）、输注Dex后10min麻醉诱导前时刻（T3）、麻醉诱导后1min（T4）、麻醉诱导后3min（T5）、插管前OPN（T6）、插管即刻（T7）、插管后1min（T8）、插管后3min（Tq）、插管后5min（T10）各时点的心率（heartrate,HR）、有创血压值（artefial blood pressure,ABP）[收缩压（systolic blood pressure,SBP）、舒张压（diastolic blood pressure,DBP）、平均动脉压mean artery pressure,MAP）]和BIS变化。结果全麻诱导前,与T1（92．6±2．5）比较,D组BIS在T2（73．2±1．9）、T3（70．1±2．3）时显著下降（P〈0．05或P〈0．01）,C组没有明显变化;全麻诱导期,与T3比较,两组BIS明显下降;气管插管期间,与T6比较,C组在T7时BIS（34．8±2．2）显著增高（P〈0．05或P〈0．01）,而D组BIS无明显变化。与C组比较,D组BIS在T2～T5、T7明显降低（P〈0．05或P〈0．01）。全麻诱导前,与T1比较,D组在T2、T3时ABP略有增高,HR显著降低（P〈0．05或P〈0．01）;全麻诱导期,与T1比较,两组ABP、HR均下降;气管插管期间,与T6比较,D组DBP、MAP、HR在T7、T8略有升高,T9、T10无明显变化（P〉0．05）,C组ABP、HR在B～T10显著增高（P〈0．05或P〈0．01）。与C组比较,D组SBP、MAP在T4-T10和DBP在T3-T10显著增高、HR在T2～T10显著降低（P〈0．05或P〈0．01）。结论静脉预注Dex能明显加深麻醉,BIS降低,减少瓣膜置换术患者气管内插管期心血管反应,血流动力学更加平稳,适合在临床中应用。     

右美托咪定对脑电双频指数监测下丙泊酚闭环靶控系统稳定性的影响

目的探讨右美托咪定在腹腔镜手术中对脑电双频指数(BIS)监测下丙泊酚闭环靶控系统(closed-loop target controlled infusion,CL-TCI)稳定性的影响。方法选择择期腹腔镜手术女性患者60例,年龄20～60岁,BMI 18～28kg/m~2,ASAⅠ或Ⅱ级,随机分为右美托咪定组(D组)和生理盐水组(S组),每组30例。麻醉诱导前10min D组泵入右美托咪定1μg/kg,10min内注射完毕;完毕后改为0.3μg·kg~(-1)·h~(-1)持续注射,S组泵入等量生理盐水。诱导完成后均由CL-TCI泵注丙泊酚,具体给药剂量由靶控系统根据BIS值自动调节,BIS目标值为45。根据术中连续记录的BIS值计算总体分数(GS)、误差绝对中位数(MDAPE)、摆动度(Wobble)。记录丙泊酚、瑞芬太尼药物用量以及血管活性药物使用例次。结果D组GS、MDAPE均明显高于S组(P0.01),两组Wobble值差异无统计学意义;D组丙泊酚用量、麻黄碱使用次数明显少于S组(P0.01),两组瑞芬太尼的用量差异无统计学意义。结论腹腔镜手术患者全身麻醉过程中使用右美托咪定联合BIS监测下CL-TCI能明显减少丙泊酚的用量,但会降低该系统的稳定性。     

右美托咪定对丙泊酚或七氟醚全麻患者脑状态指数的影响

目的观察右美托咪定对全麻患者脑状态指数的影响。方法选择择期上腹部手术的全麻患者80例,男39例,女41例,年龄25~65岁,ASAⅠ或Ⅱ级。所有患者分为四组:丙泊酚组(P组),靶控输注丙泊酚血浆浓度3.0~4.0μg/ml;丙泊酚+右美托咪定组(PD组),靶控输注丙泊酚血浆浓度1.5~2.5μg/ml,右美托咪定0.5μg/kg,输注5 min,再持续输注0.6μg·kg~(-1)·h~(-1);七氟醚组(S组),吸入1.5%~2.5%七氟醚;七氟醚+右美托咪定组(SD组),吸入1%~1.5%七氟醚,右美托咪定0.5μg/kg,输注5min,再持续输注0.6μg·kg~(-1)·h~(-1)。术中所有患者镇静指数维持在45~55。分别于麻醉前、右美托咪定持续输注30、60min测定脑状态指数(记忆加工指数、谵妄指数)。结果麻醉前四组脑状态指数差异无统计学意义。右美托咪定持续输注30、60 min时PD组记忆加工指数和谵妄指数均明显低于P组(P0.05),SD组均明显低于S组(P0.05)。结论全麻中复合应用右美托咪定能够降低患者的脑状态指数。     

右美托咪定清醒镇静对帕金森病患者脑深部电刺激植入术喉罩全麻的影响

目的探讨右美托咪定清醒镇静对帕金森病(Parkinson’s Disease,PD)患者脑深部电刺激植入术(deep brain electric stimulus implantation,DBS)喉罩全麻的影响。方法选择择期行双侧丘脑底核DBS的PD患者40例,男32例,女8例,年龄18~75岁,ASAⅠ或Ⅱ级。随机将患者分为右美托咪定组(D组)和对照组(C组),每组20例。手术分两阶段进行:第一阶段在局麻下放置电极,CT检查证实电极放置满意为第一阶段结束;第二阶段需在全麻下埋置脉冲发生器于胸前皮下。D组在入室后15 min内经静脉匀速泵入负荷剂量右美托咪定0.5μg/kg,继之以0.1~0.3μg·kg-1·h-1持续泵注至手术第一阶段结束;C组泵入同等剂量生理盐水。记录微电极受干扰和震颤减轻次数;记录患者入室时(T0)、局部浸润麻醉时(T1)、一侧电极植入时(T2)、对侧电极植入时(T3)、第一阶段结束时(T4)的Ramsay镇静评分;记录意识消失时间、喉罩置入时间、自主呼吸恢复时间和拔管时间;记录全麻开始至手术结束丙泊酚、瑞芬太尼总用量。结果两组患者微电级受干扰、震颤减轻发生率差异无统计学意义;D组T1~T4时的Ramsay评分明显高于C组(P0.05),意识消失时间、喉罩置入时间、自主呼吸恢复时间和拔管时间明显短于C组(P0.05),全麻开始至手术结束丙泊酚、瑞芬太尼总用量明显少于C组(P0.05)。结论右美托咪定可为帕金森病脑深部电刺激植入术第一阶段提供良好镇静;并能缩短第二阶段喉罩全麻诱导及苏醒时间,减少丙泊酚、瑞芬太尼用量。     

右美托咪定降低小儿Ambu AuraOnce喉罩置入所需七氟醚呼气末半数有效浓度

目的 观察右美托咪定(dexmedetomidine,Dex)1μg/kg降低小儿Ambu AuraOnce喉罩(Ambu喉罩)置入所需七氟醚呼气末半数有效浓度(median effective concentration,EC50)作用. 方法 4～10岁全身麻醉下行择期整形外科手术患儿50例,ASA分级Ⅰ级,计算机随机抽样表格法分为Dex组(D组,26例)和对照组(C组,24例).患儿入室后均采用8％七氟醚和50％氧化亚氮(nitrous oxide,N2O)吸入行麻醉诱导,建立静脉通路后停止N2O吸入,调节七氟醚吸入浓度使七氟醚呼气末EC50达到预定浓度.同时D组开始静脉输注Dex 1 μg/kg,C组注射生理盐水,10 min注射完毕后置入一次性Ambu喉罩.两组首例患儿的七氟醚呼气末EC50均设定为1.8％,采用改良Dixon up-down法确定下一例喉罩置入的七氟醚呼气末EC50,相邻七氟醚的浓度梯度值为0.2％. 结果 小儿置入Ambu喉罩时所需七氟醚呼气末EC50值(95％CI)D组和C组分别为1.44％(1.17％,1.60％)和1.77％(1.52％,2.01％). 结论 Dex 1 μg/kg可有效降低小儿置入Ambu喉罩所需七氟醚呼气末EC50.     

右美托咪定用于患儿喉罩拔除过程中的临床观察

目的探讨右美托咪定用于患儿喉罩拔除过程中的效果。方法选取40例插喉罩全身麻醉行择期手术的患儿随机分成两组,A组(n=20)右美托咪定组和B组(n=20)对照组。在患儿通气达到拔管指标后,对刺激有肢动或哭闹时A组采用静脉推注右美托咪定1μg/kg。B组不做处理。记录给药前1 min(T1)、用药后(T2)、吸痰时(T3)、拔喉罩时(T4)及拔喉罩后5 min时(T5)的平均动脉压(MBP)、心率(HR)、喉痉挛的情况。结果两组患儿T1时MBP、HR差异无统计学意义(P0.05),两组在T2、T3、T4时MBP、HR右美托咪定组明显低于对照组(P0.05),T5时MBP,HR差异无统计学意义(P0.05),而喉痉挛的发生率A明显低于B组P0.05)。结论右美托咪定用于患儿喉罩拔除过程中,对呼吸循环的影响轻,气道反应小,减少了喉痉挛的发生,且不延长苏醒时间,是安全有效的。     

不同剂量右美托咪定对丙泊酚诱导效应室靶浓度的影响

目的观察不同剂量右美托咪定在全麻患者气管插管时有效性和安全性及对丙泊酚效应室靶浓度(Ce)的影响。方法 60例全麻下行择期上腹部手术患者,随机均分为四组:D1、D2、D3、C组,分别在麻醉诱导前10min静脉泵注右美托咪定0.25μg/kg(D1组)、0.5μg/kg(D2组)和1.0μg/kg(D3组)及10ml生理盐水(C组)。麻醉诱导采用靶控输注丙泊酚,以BIS为靶控目标。丙泊酚初始Ce设为1.5μg/ml,递增梯度为0.5μg/ml,同时泵注瑞芬太尼0.2μg·kg-1·min-1。BIS≤60时推注罗库溴铵0.9mg/kg,BIS≤50并维持5s行气管插管。于输注右美托咪定前(T0)、诱导前(T1)、气管插管前(T2)、气管插管后1min(T3)、3min(T4)、5min(T5)、10min(T6)时记录SBP、DBP、HR、BIS、丙泊酚Ce。结果与T0时比较,T1时D2、D3组HR减慢、D3组SBP、DBP升高(P<0.05);与T1时比较,T2时D1组和C组SBP、DBP下降,HR减慢(P<0.05);与T2时比较,T3～T5时D1组和C组SBP、DBP升高,HR增快,T3时C组BIS升高(P<0.05)。T2～T6时丙泊酚CeD1、D2、D3组明显低于C组(P<0.05)。不同剂量右美托咪定各时点对丙泊酚Ce存在明显负相关关系。结论麻醉诱导前静脉输注不同剂量右美托咪定对丙泊酚诱导效应室浓度存在负相关关系。麻醉诱导前静脉输注右美托咪定0.5μg/kg心血管反应平稳并能显著减少诱导时所需丙泊酚Ce。     

丙泊酚和右美托咪定全麻诱导对瑞芬太尼抑制喉罩插入反应效应室浓度的影响

目的探讨右美托咪定对抑制喉罩插入反应所需瑞芬太尼剂量的影响。方法拟行乳房肿瘤切除术患者60例,随机分为三组:麻醉诱导前分别输注生理盐水(D1组)和右美托咪定0.25μg/kg(D2组)和0.5μg/kg(D3组)。泵注结束后用效应室靶控输注丙泊酚,靶浓度设定为3.5μg/ml。采用改良Dixon’s序贯法进行研究,靶控丙泊酚3min后效应室靶控输注瑞芬太尼,D1、D2和D3组设定初始靶浓度分别为1.9、1.1和0.8ng/ml,3min后插入SLIPA喉罩。如插入喉罩出现体动等阳性反应,下1例患者上调1个浓度梯度,如未出现则下1例患者下调1个浓度梯度,相邻瑞芬太尼浓度差值为0.2ng/ml,直至出现6个阳性和阴性反应交替现象。阳性和阴性反应交替的中点对应的瑞芬太尼浓度的均值为瑞芬太尼抑制喉罩插入反应的半数有效效应室浓度(Ce50)。结果 D1、D2和D3组瑞芬太尼抑制插入喉罩反应的Ce50(95%CI)分别为1.90ng/ml(1.65～2.15ng/ml)、1.05ng/ml(0.91～1.20ng/ml)和0.55ng/ml(0.32～0.79ng/ml)。D2和D3组Ce50均明显低于D1组,且D3组Ce50明显低于D2组(P0.05)。结论丙泊酚全麻时应用右美托咪定能剂量依赖性地减少插入喉罩所需的瑞芬太尼用量。     

脑电双频指数指导下不同麻醉诱导方式对喉罩插入条件的影响

目的 观察脑电双频指数(BIS)指导下不同麻醉诱导方式对喉罩插入条件的影响.方法 60例择期行宫腔镜手术患者,ASAⅠ或Ⅱ级,根据诱导方式的不同随机均分为三组:七氟醚复合丙泊酚组(SP组)、七氟醚组(S组)及丙泊酚组(P组).SP组肺活量法吸入七氟醚,待患者意识消失后静脉注射丙泊酚;S组以肺活量法吸入七氟醚;P组静脉泵注丙泊酚.BIS值稳定于40～50超过20 s后插入喉罩.记录诱导开始至成功插入喉罩的时间及成功率;评估下颌松弛度评分和喉罩插入后咳嗽及肢体运动评分.结果 诱导至喉罩插入时间S组＞SP组＞P组(P＜0.05).呼吸暂停发生率P组(40％)明显高于SP和S组(均为0)(P＜0.05).不自主肢体运动发生率P组高于SP和S组(35％ vs 5％和10％,P＜0.05).结论 BIS指导下七氟醚复合丙泊酚诱导较丙泊酚或七氟醚诱导能提供更好的喉罩插入条件.     

右美托咪定对后腹腔镜术中应激反应的影响

目的 探讨右美托咪定在后腹腔镜术中对应激反应的影响.方法 择期行后腹腔镜下肾癌根治术的患者60例,男48例,女12例,年龄35～75岁,体重50～81 kg,分为右美托咪定组(D组)和对照组(C组),每组30例.全身麻醉诱导前,D组10 min内静脉泵入右美托咪定1μg/kg,续以0.5 μg·kg-1·h 1泵入,手术结束前30 min停药.C组给予等量0.9％氯化钠注射液.所有患者采用静脉注射咪达唑仑0.02～0.04 mg/kg、丙泊酚1.0～2.0 mg/kg、顺式阿曲库铵0.2 mg/kg及舒芬太尼0.5 μg/kg进行麻醉诱导.两组患者术中连续监测BP、HR、ECG、SpO2,记录开始诱导泵入右美托咪定前(T0)、气管插管即刻(T1)、开始气腹时(T2)、拔出气管导管后即刻(T3)和拔管5min后(T4)的MAP和HR,并于各时点抽取非静脉输液侧肘静脉血,放免法测定血浆皮质醇(Cor)和血管紧张素-Ⅱ(A-Ⅱ)的水平.结果 与C组比较,T0～T3时D组MAP明显降低,HR明显减慢(P＜0.05);与C组比较,T1～T3时D组的Cor浓度明显降低(P＜0.05),T4时D组的A-Ⅱ浓度明显降低(P＜0.05).结论 全麻中加入右美托咪定可以抑制围术期应激反应.     

小儿斜视手术七氟醚麻醉拔除喉罩的最佳脑电双频指数

目的观察小儿斜视手术七氟醚麻醉下拔除喉罩的最佳脑电双频指数(BIS)。方法择期行斜视手术患儿120例依据拔除喉罩时的BIS范围随机均分为三组:I组,75≤BIS<85;Ⅱ组,65≤BIS<75;Ⅲ组,55≤BIS<65。三组均采用七氟醚吸入全麻。记录患儿拔除时血流动力学变化、呼气末七氟醚浓度(CETSev)、PETCO2及并发症。结果Ⅲ组拔除喉罩时喉痉挛、低氧血症、咳嗽、屏气的发生率均明显低于Ⅰ、Ⅱ组(P<0.05)。结论小儿斜视手术七氟醚麻醉拔除喉罩的最佳BIS为55~65。     

喉罩通气在甲状腺切除手术中对应激反应和通气的影响

目的 观察甲状腺切除手术中运用喉罩通气对血流动力学、应激和通气功能的影响.方法 择期行甲状腺切除术患者50例,年龄35～65岁,ASA Ⅰ或Ⅱ级,随机均分为气管导管组(T组)和喉罩组(L组).记录患者入室安静5 min时(T0)、插管前即刻(T1)、插管后即刻(T2)、插管后3 min(T3)、拔管时(T4)和拔管后3 min(T5)的MAP和HR,并于上述时间点采静脉血检测肾上腺素(E)、去甲肾上腺素(NE)水平.记录间歇通气10min(T6)、30min(T7)和60min(T8)时的分钟通气量(MV)、气道峰压(Ppeak)、潮气量(VT)和PETCO2.结果 两组T6～T8时MV、VT、SpO2的差异无统计学意义.L组T8时的Ppeak和PETCO2高于T组(P＜0.05),L组T2～T5时的MAP较T组降低,HR减慢(P＜0.05).T组T3～T5时的E、NE水平高于L组.T组T5时的E、NE水平高于T0(P＜0.05),而L组的E、NE水平在T5与T0时比较差异无统计学意义.结论 喉罩通气麻醉操作简便,通气可靠,对心血管系统刺激性小.     

Use of the bispectral index to predict a positive awareness reaction to laryngeal mask airway-Fastrach insertion and intubation

Aim:  To determine whether the bispectral index (BIS) can be monitored to predict and indicate an awareness reaction to laryngeal mask airway–Fastrach (LMA–Fastrach) insertion and intubation at BIS values between 40 and 60.
Methods:  Fifty-one American Society of Anesthesiologists' (ASA) class I or II status patients aged over 20 years were included in this study. Midazolam 0.1 mg/kg was given for pre-medication, 30 min before induction. For induction, a 0.1-μg/kg bolus injection of remifentanil was followed by infusion, and propofol was administered until the eyelash reflex disappeared; the infusion rate was adjusted to maintain BIS values between 40 and 60. Loss of the eyelash reflex, loss of response to verbal commands, yawning and total propofol consumption were recorded. Patients were tested for awareness twice at 1-min intervals using the isolated forearm technique. The test was considered to be positive if the patient squeezed a hand when asked; after muscle relaxation, the patient was intubated and the test was repeated. In the recovery room and ward, patients were asked whether they could recall this event.
Results:  Seven patients tested positive: two following LMA–Fastrach insertion and the remaining five following intubation. None of the patients had recall.
Conclusion:  Awareness during anaesthesia may occur at BIS levels that indicate adequate anaesthesia, but this is not associated with recall of the events later.     

Desflurane requirements for laryngeal mask airway insertion during inhalation induction

Purpose  We hypothesized that the simultaneous use of low concentrations (<6%) of desflurane, nitrous oxide (N₂O), and fentanyl would allow a laryngeal mask airway (LMA) to be inserted safely with inhalation induction of desflurane, even in nonparalyzed patients. This prospective, observational study was performed to determine the 50% effective concentration (EC₅₀) of desflurane for LMA insertion in such patients. Methods  Twenty-two adult patients undergoing ambulatory surgical procedures under general anesthesia using an LMA were included in the study. Fentanyl was administered intravenously at 1.5 μg·kg⁻¹, and anesthesia was induced with desflurane in 50% N₂O and oxygen, using a normal tidal volume breathing technique. Subsequently, a preselected steady-state end-tidal desflurane concentration was maintained for 10 min before insertion of the LMA. Successful LMA insertion was defined as the absence of adverse airway responses until cuff inflation. Target concentrations of desflurane for LMA insertion were determined using a modified Dixon’s up-and-down method (starting dose, 5%; step size, 0.5%). Results  All 22 patients completed the study without adverse events related to airway irritation. The EC₅₀ of desflurane for insertion of the LMA was determined to be 3.61 ± 0.31%, and the 95% confidence interval (CI) of the EC₅₀ obtained using probit analysis was 3.13–3.90. Conclusion  We demonstrated that N₂O-desflurane inhalation induction with a normal tidal breathing technique after premedication with fentanyl can be used safely without any adverse airway events in nonparalyzed patients. In such patients, the EC₅₀ of desflurane for successful LMA insertion was 3.61 ± 0.31% (95% CI, 3.13–3.90).     

瑞芬太尼抑制喉罩插入心血管反应的半数效应室靶浓度

目的 测定同一麻醉深度下,瑞芬太尼抑制妇科腹腔镜手术患者喉罩插入心血管反应的半数效应室靶浓度(EC<,50>).方法 择期妇科腹腔镜手术患者31例,采用咪达唑仑-丙泊酚-维库溴铵-雷米芬太尼顺序诱导,给予达咪唑仑、丙泊酚,脑电双频指数(BIS)稳定在45～55时,给予维库溴铵,然后按上下序贯法靶控输注(TCI)瑞芬太尼.瑞芬太尼血浆浓度与效应室浓度平衡时开始插入喉罩.出现8个心血管反应阳性阴性拐点时终止研究.结果 研究进行至第31例患者时出现8个心血管反应阳性阴性拐点,其中29例患者纳入分析.瑞芬太尼抑制喉罩插入心血管反应的EC<,50>为2.0 ng/ml,95%可信区间为1.8～2.2 ng/ml.结论 维持BIS 45～55的情况下,瑞芬太尼抑制喉罩插入心血管反应的EC<,50>为2.0 ng/ml.     

丙泊酚靶控输注全麻诱导时BIS值与机体应激反应的关系

目的观察丙泊酚靶控输注(TCI)用于全麻诱导时,脑电双频指数(BIS)值与应激反应的关系。方法30例气管插管全麻下手术患者随机分为三组,每组10例。Ⅰ组BIS值维持在36~45,Ⅱ组46~55,Ⅲ组56~65,分别于麻醉诱导前(T0)、插管即刻(T1)以及插管后1min(T2)、3min(T3)、5min(T4)和10min(T5)记录HR和MAP,同期抽取桡动脉血测定血糖和皮质醇。结果Ⅰ组MAP、HR于T3、T4时持续下降(P<0.05),且T3、T4时MAP低于Ⅲ组(P<0.05);Ⅱ组T4时MAP低于T0时(P<0.05);Ⅲ组血糖和皮质醇水平T2、T3时高于T0时(P<0.05或P<0.01),血糖T2~T4时较Ⅰ组升高(P<0.05或P<0.01),T3、T4时较Ⅱ组升高(P<0.05),T2、T3时皮质醇水平明显高于Ⅰ组和Ⅱ组(P<0.05或P<0.01)。结论丙泊酚TCI用于全麻诱导时,将BIS值控制在46~55,在有效减轻应激反应的同时,能维持血流动力学的相对稳定。     

艾司洛尔对丙泊酚麻醉诱导过程中脑电双频指数的影响

目的观察艾司洛尔用于丙泊酚麻醉诱导插管时脑电双频指数(BIS)的变化。方法30例ASAⅠ或Ⅱ级患者随机分为两组,对照组静注生理盐水10ml负荷量后静滴生理盐水,用药组艾司洛尔1mg/kg稀释于生理盐水10ml静注后以250μg.kg-1.min-1微量泵输入,然后静注丙泊酚2mg/kg,当两组BIS降至40~50时静注芬太尼2μg/kg、阿曲库铵0.5mg/kg行经口明视气管插管。监测给药前、诱导前、插管前、插管后1、3、5minBIS、MAP及HR,并观察插管后各时点与插管前BIS、MAP、HR的变化差值△BIS、△MAP及△HR。结果插管前对照组及用药组BIS变化差异无显著意义。插管后1、3、5min对照组BIS较插管前显著升高,用药组BIS与插管前比较差异无显著意义,两组间比较差异有显著意义(P<0.05)。插管后对照组△BIS变化最大百分比为40%,与用药组的6.8%相比差异有极显著意义(P<0.01)。插管后1、3min对照组MAP、HR显著高于插管前,两组比较差异无显著意义;插管后对照组△MAP及△HR变化最大百分比为55%及40%,明显高于用药组的29%及15%。结论艾司洛尔用于丙泊酚麻醉诱导插管时,对插管前BIS无影响,插管后可抑制BIS的增加。     

Hemodynamic and bispectral index responses to tracheal intubation during isoflurane or sevoflurane anesthesia

Purpose.The effects of volatile anesthetics on change in the bispectral index (BIS) due to tracheal intubation are unclear. We investigated hemodynamic and BIS responses to intubation during isoflurane or sevoflurane anesthesia. Methods.After obtaining Institutional Review Board approval and informed consent, we randomly allocated 40 patients of American Society of Anesthesiologists (ASA) physical status I to receive either isoflurane (ISO group; n = 20) or sevoflurane (SEV group; n = 20). The patients were anesthetized with thiamylal and were ventilated with 100% oxygen, using a mask. The inspired concentrations of isoflurane and sevoflurane were gradually increased and maintained at end-tidal anesthetic concentrations of 2 minimum alveolar concentration (MAC) during the study period. Tracheal intubation was performed 15min after the end-tidal anesthetic concentrations had reached 2 MAC. Mean arterial pressure (MAP), heart rate (HR), and BIS were recorded before induction, at the loss of consciousness, before laryngoscopy, and at 1, 3, and 5min after intubation. Results.Anesthesia with 2 MAC volatile anesthetics increased HR in the ISO group, and decreased MAP in the SEV group. The BIS value decreased from 95 ± 3 and 96 ± 2 before thiamylal to 39 ± 9 and 38 ± 10 before intubation in the ISO and SEV groups, respectively. MAP and HR were significantly increased in both groups 1 and 3min after intubation, but BIS remained unchanged. Conclusion.Anesthesia with 2 MAC of isoflurane and sevoflurane was effective to suppress the change in BIS due to intubation but was not sufficient to prevent changes in hemodynamic responses.