脑电双频指数监测在临床特殊情况中的应用

随着临床监测控术的发展，脑电监测有望成为临床麻醉，急诊及重症监护病房的常规监测手段，其中研究较多的脑电双频指数（BIS）已在麻醉诱导，维持，恢复等方面显示出优势。近年也有研究报道在特殊情况下应用BIS监测，包括在颅脑损伤，低温体外循环，心跳骤停等，为临床更深一步应用BIS提供了帮助。     

脑电双频谱分析用于地氟醚复合氧化亚氮吸入时麻醉深度的判断

目的：通过观察地氟醚复合Ｎ２Ｏ吸入麻醉过程中脑电双频谱指数（ＢＩＳ）的进一步评价ＢＩＳ在麻醉深度监测中的应用价值。方法：患者２０例,气管插管后后用５０％Ｏ２＋５０％Ｎ２Ｏ＋地氟醚维持麻醉。地氟醚初始吸入浓度６％,分别于呼气末浓度达到０．５、０．７５、１．０、１．２５６ １．５ＭＡＣ时记录ＢＩＳ、Ｂ客ＨＲ等指标,然后维持呼气末２３．９％（１．３ＭＡＣ０,１５分钟后开始手术,观察切皮时患者有无反应。术     

Comparison of Bispectral Index and Composite Auditory Evoked Potential Index for Monitoring Depth of Hypnosis in Children

Background: In pediatric patients, the Bispectral Index (BIS), derived from the electroencephalogram, and the composite A-Line autoregressive index (cAAI), derived from auditory evoked potentials and the electroencephalogram, have been used as measurements of depth of hypnosis during anesthesia. The performance and reliability of BIS and cAAI in distinguishing different hypnotic states in children, as evaluated with the University of Michigan Sedation Scale, were compared.

Methods: Thirty-nine children (aged 2-16 yr) scheduled to undergo elective inguinal hernia surgery were studied. For all patients, standardized anesthesia was used. Prediction probabilities of BIS and cAAI versus the University of Michigan Sedation Scale and sensitivity/specificity were calculated.

Results: Prediction probabilities for BIS and cAAI during induction were 0.84 for both and during emergence were 0.75 and 0.74, respectively. At loss of consciousness, the median BIS remained unaltered (94 to 90; not significant), whereas cAAI values decreased (60 to 43; P < 0.001). During emergence, median BIS and cAAI increased from 51 to 74 (P < 0.003) and from 46 to 58 (P < 0.001), respectively. With respect to indicate consciousness or unconsciousness, 100% sensitivity was reached at cutoff values of 17 for BIS and 12 for cAAI. One hundred percent specificity was associated with a BIS of 71 and a cAAI of 60. To ascertain consciousness, BIS values greater than 78 and cAAI values above 52 were required.     

Does the Use of Electroencephalographic Bispectral Index or Auditory Evoked Potential Index Monitoring Facilitate Recovery after Desflurane Anesthesia in the Ambulatory Setting?

Background: Analogous to the Bispectral Index(R) (BIS(R)) monitor, the auditory evoked potential monitor provides an electroencephalographic-derived index (AAI), which is alleged to correlate with the central nervous system depressant effects of anesthetic drugs. This clinical study was designed to test the hypothesis that intraoperative cerebral monitoring guided by either the BIS or the AAI value would facilitate recovery from general anesthesia compared with standard clinical monitoring practices alone in the ambulatory setting.

Methods: Sixty consenting outpatients undergoing gynecologic laparoscopic surgery were randomly assigned to one of three study groups: (1) control (standard practice), (2) BIS guided, or (3) AAI guided. Anesthesia was induced with 1.5-2.5 mg/kg propofol and 1-1.5 [mu]g/kg fentanyl given intravenously. Desflurane, 3%, in combination with 60% nitrous oxide in oxygen was administered for maintenance of general anesthesia. In the control group, the inspired desflurane concentration was varied based on standard clinical signs. In the BIS- and AAI-guided groups, the inspired desflurane concentrations were titrated to maintain BIS and AAI values in targeted ranges of 50-60 and 15-25, respectively. BIS and AAI values, hemodynamic variables, and the end-tidal desflurane concentration were recorded at 5-min intervals during the maintenance period. The emergence times and recovery times to achieve specific clinical endpoints were recorded at 1- to 10-min intervals. The White fast-track and modified Aldrete recovery scores were assessed on arrival in the PACU, and the quality of recovery score was evaluated at the time of discharge home.

Results: A positive correlation was found between the AAI and BIS values during the maintenance period. The average BIS and AAI values (mean +/- SD) during the maintenance period were significantly lower in the control group (BIS, 41 +/- 10; AAI, 11 +/- 6) compared with the BIS-guided (BIS, 57 +/- 14; AAI, 18 +/- 11) and AAI-guided (BIS, 55 +/- 12; AAI, 20 +/- 10) groups. The end-tidal desflurane concentration was significantly reduced in the BIS-guided (2.7 +/- 0.9%) and AAI-guided (2.6 +/- 0.9%) groups compared with the control group (3.6 +/- 1.5%). The awakening (eye-opening) and discharge times were significantly shorter in the BIS-guided (7 +/- 3 and 132 +/- 39 min, respectively) and AAI-guided (6 +/- 2 and 128 +/- 39 min, respectively) groups compared with the control group (9 +/- 4 and 195 +/- 57 min, respectively). More importantly, the median [range] quality of recovery scores was significantly higher in the BIS-guided (18 [17-18]) and AAI-guided (18 [17-18]) groups when compared with the control group (16 [10-18]).     

心率变异性复杂度分析和脑电双频谱指数在监测全身麻醉时的相关性

目的：观察全身麻醉时心率变异性分析中复杂度和脑电双频谱指数（BIS）的变化,探讨复杂度和BIS在监测麻醉深度时的相关性。方法：30例全身麻醉病人,测定麻醉前（T1）、诱导插管（T2）、术中（T3）、苏醒（T4）4个时间点各5min的心率（HR）、平均动脉压（MAP）、脑电双频谱指数（BIS）和复杂度变化。结果：HR在T2、T3和T4较T1值升高（P〈0.01或0.05）。MAP在T2时较T1值降低（P〈0.05）,T3和T4较T1值升高（P〈0.05）,而T3和T4相比变化较大（P〈0.01）。BIS值在各时点较T1值下降明显（P〈0.01）,其中T4较T1略下降（P〈0.05）,T3与T2时相比明显降低（P〈0.01）,而T4较T3明显升高（P〈0.01）。复杂度值的T1值均大于各个点（P〈0.01或0.05）,其T4较T2和T3时升高（P〈0.05）,T3较T2时升高（P〈0.05）。结论：作为心率变异性非线性指标的复杂度能描述围术期心脏自主神经功能状态的变化,但其与BIS并无相关性。     

安氟醚闭环靶控麻醉应用脑电双频指数的临床研究

目的：探讨将脑电双频指数（BIS）作为安氟醚闭环靶控麻醉反馈控制的变量指标的可行性。方法：60例择期剖胸手术患者，随机分为试验组和对照组，每组30例。两组均以BIS值55为控制麻醉深度的目标，试验组采用吸入麻醉药闭环靶控系统实施麻醉深度维持；对照组由麻醉医师手动调控安氟醚挥发罐实施麻醉深度维持。记录并比较两组实时的BIS值、血压、心率、辅助药剂量、安氟醚用量、苏醒时间、苏醒期躁动和术中知晓等数据。结果：两组患者麻醉维持期间的BIS基本在预定值55上下波动，其变化趋势基本一致。两组患者的血液动力学存在差异，闭环靶控组在安氟醚吸入后的血压下降幅度明显大于对照组，但在切皮后血压上升的幅度则对照组明显偏低，手术过程中的血压也较对照组者维持较低。安氟醚闭环靶控组的安氟醚总用量和辅助药使用量均明显低于手动控制组。两组均未发生术中知晓。结论：在剖胸后的单肺通气条件下，安氟醚闭环靶控系统能保证麻醉过程及血液动力学稳定，无术中知晓发生，麻醉药用量可减少。     

脑电双频指数用于小儿镇静及麻醉深度监测的研究进展

大量研究证实,脑电双频指数(BIS)与较大小儿的镇静及麻醉深度有较好的相 关性,与麻醉药物浓度呈负相关,能较好地评价意识水平。但对于婴儿,BIS监测的有效性尚 有待于进一步研究。     

脑电熵在临床麻醉深度监测的应用

麻醉深度一直是麻醉领域中备受关注的问题。全身麻醉是一种复杂且特殊的状态．包括催眠、记忆缺失、疼痛应激抑制和肌肉松弛等多方面的因素构成。传统的生命体征．如：心率、血压．呼吸．瞳孔等．已不能准确的反应麻醉深度。随着脑电技术的发达．目前已有听觉诱发电位、脑电双频指数（bispectral index．BtS）．脑电熵（Entropy）等多种监测方法．本文就脑电熵在麻醉深度中的应用以及这几年的进展作一综述。     

异氟醚全麻深度的多指标判断

由于箭毒和新的麻醉技术的应用，乙醚麻醉分期已不再适用，急需寻找新的方法判断麻醉深度。本研究通过观察６０例在模拟刺激和手术刺激下异氟醚０．４－１．６ＭＡＣ呼气末浓度与脑电频率和波幅、额肌电波幅、手指动脉收缩和舒张压，肱动脉收缩和舒张压，批端容积波波幅，心率，诱发性食管下段收缩性，吸呼末氧浓度差，呼末二氧化碳浓度１２例指标的相关性分析，对上述各指标在全麻深度判断中的作用进一步评价。     

Effects of Bispectral Index Monitoring on Recovery from Surgical Anesthesia in 1,580 Inpatients from an Academic Medical Center

Background: The purpose of this study was to determine whether monitoring Bispectral Index (BIS) would affect recovery parameters in patients undergoing inpatient surgery.

Methods: Anesthesia providers (n = 69) were randomly assigned to one of two groups, a BIS or non-BIS control group. A randomized crossover design was used, with reassignment at monthly intervals for 7 months. Duration of time in the postanesthesia care unit, time from the end of surgery to leaving the operating room, and incidence of delayed recovery (> 50 min in recovery) were compared in patients treated intraoperatively with or without BIS monitoring. Data were analyzed by analysis of variance, unpaired t test, or chi-square test as appropriate.

Results: One thousand five hundred eighty patients in an academic medical center were studied. The mean BIS in the monitored group was 47. No differences were found in recovery parameters between the BIS-monitored group and the control group when comparisons were made using all subjects or when data were analyzed within anesthetic subgroups stratified by anesthetic agent or duration of anesthesia. There were some small reductions in the intraoperative concentration of sevoflurane (but not isoflurane).     

全身麻醉深度监测研究的新进展

麻醉深度监测是临床麻醉工作的重要任务之一。在全身麻醉时,意识的传统体征(血压、心率、呼吸和瞳孔等)已不能准确反映麻醉深度。目前,其研究重点集中在脑电活动方面,如脑电双频指数、听觉诱发电位指数等,虽然显现出一定的优势,但也存在着不少的缺陷。新近研发的Nareotrend,人工神经网络、患者状态指数以及唾液中的cGMP含量测定,使麻醉深度监测的研究更加深入,现就目前的研究进展予以综述。     

Effects of Bispectral Index Monitoring on Ambulatory Anesthesia: A Meta-analysis of Randomized Controlled Trials and a Cost Analysis

Background: Ambulatory surgery is growing in popularity worldwide. For example, 50-70% of surgical procedures in North America are performed on an ambulatory basis. Use of Bispectral Index (BIS) monitoring for titration of general anesthesia may allow use of less anesthetics, reduction in side effects, and faster patient recovery.

Methods: MEDLINE and other databases were searched for randomized controlled trials examining the use of BIS monitoring versus standard practice in ambulatory surgery patients. Outcomes were extracted from these articles, and a meta-analysis was performed.

Results: One thousand three hundred eighty subjects from 11 trials were included in the meta-analysis. The use of BIS monitoring significantly reduced anesthetic consumption by 19%, reduced the incidence of nausea/vomiting (32% vs. 38%; odds ratio, 0.77), and reduced time in the recovery room by 4 min. However, these benefits did not result in significant reduction in time until patient discharge from the ambulatory surgery unit. Cost analysis using pooled costs to reflect North America, Europe, and Asia indicated that use of BIS monitoring increased the cost per patient by 5.55 US dollars because of the cost of BIS electrodes.     

脑电双频指数用于门诊宫腔镜通液术麻醉监测的价值

目的观察脑电双频指数（bispectral index,BIS）监测对门诊宫腔镜通液术患者麻醉过程及恢复的意义。方法 2010年10月～2011年3月选择我院门诊择期在丙泊酚-舒芬太尼静脉麻醉下行宫腔镜通液术120例,按随机数字表随机分为BIS监测组（n=60）与常规监测组（n=60）。静脉给予舒芬太尼5μg、丙泊酚1.0 mg/kg负荷量后,丙泊酚维持量BIS监测组根据BIS（40～55）调节,常规监测组仅根据患者临床体征调节。比较2组丙泊酚用量、术中反应、手术时间及留院观察时间等。结果 BIS监测组丙泊酚用量（84.1±10.7）mg,显著少于常规监测组（108.7±15.3）mg（t=-10.206,P=0.000）。扩宫口时肢动,BIS监测组2例,常规监测组7例,2组发生率无统计学差异（χ2=1.922,P=0.166）。常规监测组平均动脉压（MAP）在麻醉诱导入睡后（t=-4.379,P=0.000）、扩张宫颈时（t=-5.863,P=0.000）、通液时（t=-3.073,P=0.003）,显著低于BIS监测组。术中知晓BIS监测组无发生,常规监测组3例,2组发生率无统计学差异（Fisher’s检验,P=0.244）。结论 BIS监测用于门诊宫腔镜通液术麻醉,预防麻醉药用量不足或逾量,减轻血流动力学改变,有利于提高麻醉安全,减少并发症的发生。     

麻醉深度监测在整形美容外科麻醉中的应用效果

目的 探讨麻醉深度监测在整形美容外科麻醉中的应用效果。方法 选取2020年3月-2022年12月 于我院行整形美容手术的80例患者为研究对象,以随机数字表法分为对照组和试验组,各40例。所有患者 术中均采用全凭静脉麻醉,对照组术中根据麻醉者经验调节麻醉药物用量,试验组术中根据脑电双频谱指 数（BIS）监测结果调节麻醉药物用量,比较两组血流动力学指标、应激指标、苏醒时间及不良事件发生 情况。结果 试验组T1、T2、T3时段HR、MAP水平均优于对照组（P＜0.05）;试验组T1、T2、T3时E、 NE、Cor水平均低于对照组（P＜0.05）;试验组睁眼时间、语言指令反应恢复时间、定向力恢复时间均短 于对照组（P＜0.05）;试验组不良事件发生率为5.00%,低于对照组的20.00%（P＜0.05）。结论 麻醉深度 监测在整形美容外科麻醉中的应用效果确切,可维持围术期血流动力学的稳定性,减轻手术应激反应,加 快患者术后苏醒速度,有利于降低不良事件发生几率。     

Epidural Lidocaine Decreases Sevoflurane Requirement for Adequate Depth of Anesthesia as Measured by the Bispectral Index ® Monitor

Background: Epidural anesthesia potentiates sedative drug effects and decreases minimum alveolar concentration (MAC). The authors hypothesized that epidural anesthesia also decreases the general anesthetic requirements for adequate depth of anesthesia as measured by Bispectral Index (BIS).

Methods: After premedication with 0.02 mg/kg midazolam and 1 [mu]g/kg fentanyl, 30 patients aged 20-65 yr were randomized in a double-blinded fashion to receive general anesthesia with either intravenous saline placebo or intravenous lidocaine control (1-mg/kg bolus dose; 25 [mu]g [middle dot] kg-1 [middle dot] min-1). A matched group was prospectively assigned to receive epidural lidocaine (15 ml; 2%) with intravenous saline placebo. All patients received 4 mg/kg thiopental and 1 mg/kg rocuronium for tracheal intubation. After 10 min of a predetermined end-tidal sevoflurane concentration, BIS was measured. The ED50 of sevoflurane for each group was determined by up-down methodology based on BIS less than 50 (MACBIS50). Plasma lidocaine concentrations were measured.

Results: The MACBIS50 of sevoflurane (0.59% end tidal) was significantly decreased with lidocaine epidural anesthesia compared with general anesthesia alone (0.92%) or with intravenous lidocaine (1 %;P < 0.0001). Plasma lidocaine concentrations in the intravenous lidocaine group (1.9 [mu]g/ml) were similar to those in the epidural lidocaine group (2.0 [mu]g/ml).