脑电双频指数监测临床应用的新进展

背景 麻醉深度判断一直是临床医师非常关注的问题.脑电双频指数（bispectral index,BIS）监测是目前应用最为广泛的量化麻醉深度的监测手段,随着BIS监测的普及,其应用价值也不断得到更深入的认识. 目的 就BIS临床应用的新进展作一综述. 内容 术中BIS监测可以使麻醉医师以适合的麻醉深度为目标个体化按需给药,既有助于避免麻醉过浅导致术中知晓,也可避免不必要的麻醉过深而造成的术后恢复延迟,这对于慢性肝病患者的麻醉尤其重要.术中BIS监测有助于通过避免麻醉过深加快患者术后认知功能恢复,并可能改善患者远期预后.对于围术期全脑缺血的高危患者,术中BIS突然下降可能提示脑灌注不足.BIS监测可能还有助于对心跳骤停、心肺复苏后患者的预后判断,但用于预后判断的最佳监测时间和界值仍有待进一步研究阐明. 趋向 术中BIS监测能够预防术中知晓和避免麻醉过深,降低术后谵妄的发生率,并在肝病患者神志判断和麻醉、高危手术围术期脑缺血监测及心肺复苏患者的预后判断等领域有很好的应用价值.     

监测脑电双频谱指数预防全麻患者术中知晓的效果:meta分析

目的 采用meta分析评价脑电双频谱指数(BIS)监测用于预防全麻患者术中知晓的效果.方法 检索Cochrane Central Register of Controlled Trials (Central)、Pubmed、Medline、EMBASE等数据库有关BIS监测与未应用BIS监测全麻患者术中知晓效果的临床、随机、对照研究.应用Cochrane协作网系统评价法对纳入文献质量进行评价和资料提取,评价指标为术中知晓发生率.采用RevMan5.1软件进行meta分析.结果 共纳入5项研究,包括34181例患者,其中应用BIS监测患者17432例,术中知晓发生率0.132％;未应用BIS监测患者16749例,术中知晓发生率0.245％,BIS监测组与未应用BIS监测组术中知晓发生率比较差异无统计学意义(P＞0.05)；根据麻醉方式不同进一步分析:在吸入麻醉中,应用BIS监测患者13288例,术中知晓发生率0.128％,未应用BIS监测患者13202例,术中知晓发生率0.113％,BIS监测组与未应用BIS监测组术中知晓发生率比较差异无统计学意义(P＞0.05)；在全凭静脉麻醉中,应用BIS监测患者4144例,术中知晓发生率0.145％,未应用BIS监测患者3547例,术中知晓发生率0.733％,BIS监测组术中知晓发生率明显低于未应用BIS监测组(P＜0.01).结论 监测BIS可预防全凭静脉麻醉患者术中知晓的发生,但不能预防吸入麻醉患者术中知晓的发生.     

脑电双频指数监测对老年慢性贫血患者术后谵妄发生率的影响

目的 探讨BIS监测对老年慢性贫血患者腹部手术术后谵妄(postoperative delirium,POD)发生率的影响. 方法 180例择期行全身麻醉手术患者,按随机数字表法分为两组(每组90例):BIS监测组及对照组,对照组采用常规麻醉,BIS监测组维持BIS值于40～60.记录患者入室后(T0)、诱导后(T1)、插管即刻(T2)、插管后3 min(T3)、切皮(T4)、术中1h(T5)及手术结束(T6)各时间点的血流动力学指标.观察记录患者麻醉期间丙泊酚用量、手术时间、拔管时间、清醒时间,及POD发生情况. 结果 BIS监测组谵妄总发生率17.8％,低于对照组的31.1％(P＜0.05);其中,BIS监测组谵妄第1天发生率13.3％,明显低于对照组的28.9％(P＜0.05),第2天发生率5.6％,低于对照组的14.4％(P＜0.05);BIS监测组谵妄持续时间明显低于对照组(P＜0.05).BIS监测组术后清醒拔管时间[(26±8) min]及住院时间[(11.5±2.3)d]显著短于对照组[(41±12) min、(12.6±4.4)d](P＜0.05). 结论 BIS监测下麻醉可降低老年合并慢性贫血患者POD发生率,减少谵妄持续时间.     

B-Aware试验中BIS监测对远期生存率的影响

背景当使用脑电双频指数（bispectral index,Bis）监测指导麻醉药用量时,通常仅需要较低剂量的镇静药,如果用较低剂量的麻醉药,术中低血压和器官毒性作用也许能避免。然而,这是否能减少严重并发症和术后死亡率还存争议。B．Aware试验将2463例术中知晓高危的患者随机分为BIS指导麻醉组和常规麻醉组。我们假设使用BIS指导麻醉组患者死亡、心肌梗死（myocardial infarction,MI）和卒中的风险都低于常规麻醉组患者。方法对术后30天尚存活的所有患者的医疗记录进行回顾,记录他们的死亡日期、死亡原因以及心肌梗死或卒中的发生情况．然后对所有存活的点者主牛行由话随访．本研究的主要终点是存活。结果随访时间中位值4．1年（全距：0－6．5年）,参加试验的患者中有548例（22．2％）术后死亡,220例（8．9％）发生了心肌梗死,115例（4．7％）发生卒中。BIS监测组与常规麻醉组的死亡风险没有显著差异{危害比=0．86[95％可信区间（CI）：0．72-1．01];P=0．07]。但是,倾向性评分分析显示,BIS值〈40、持续时间〉5分钟的患者与其他BIS监测组的患者相比,死亡的危害比为1．41（95％CI：1．02-1．95;P=0．039）,并且心肌梗死的优势比（OR）为1．94（95％CI：1．12-3．35;P=0．01）,卒中的优势比为3．24（95％CI：1.29-8．07;P=0．01）。结论在B-Aware试验患者中,采用了BIS指导麻醉且从未出现BIS值低于40并持续超过5分钟,与存活率的增加及并发症的减少相关。     

脑电双频谱指数监测提高麻醉管理及全麻苏醒质量Meta分析研究

目的 评价脑电双频谱指数（BIS）监测是否改善麻醉管理和麻醉苏醒质量。方法按照制定的检索策略检索Pubmed和Medline—CDRom数据库（1990年1月至2004年1月），随后按照一定的入选原则找出符合要求的文献。按已制定的研究评价标准进行筛选，共10篇文献纳入最终的Meta分析。结果 BIS监测在镇痛药用量一致的情况下可减少催眠药物的用量。吸入麻醉中BIS监测可减少吸入麻醉药用量，但肌松药用量增加。BIS组病人睁眼时间、言语指令反应恢复时间、拔管时间、定向力恢复时间均缩短。BIS监测对术后恶心呕吐及术后疼痛的发生率没有影响。BIS监测减少术中知晓与术后记忆发生的证据尚不足。结论 BIS监测能减少全身麻醉中药物用量并提高麻醉苏醒质量。     

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。     

脊柱手术患者术后谵妄的危险因素分析

目的 探讨脊柱手术患者术后谵妄（POD）的危险因素,并建立脊柱手术患者POD的风险预测模型。
方法 回顾性收集行脊柱手术患者1 075例,男570例,女505例,年龄≥18岁,BMI 18～35 kg/m²,ASA Ⅰ—Ⅲ级。采用意识模糊评估法-中文修订版（CAM-CR）量表进行评估,根据是否发生POD将患者分为两组：POD组和非POD组。采用单因素分析筛选POD的相关因素,将P＜0.1的相关因素纳入二元Logistic回归模型,分析脊柱手术患者POD的独立危险因素并建立预测模型。绘制受试者工作特征（ROC）曲线并计算ROC曲线下面积（AUC）评价预测模型的价值。
结果 有84例（7.81%）患者发生POD。与非POD组比较,POD组年龄明显增大（P＜0.05）,ASA分级＞Ⅱ级、METs＜4比例明显升高（P＜0.05）,手术侵入类型级别明显升高（P＜0.05）,BIS监测比例明显降低（P＜0.05）,竖脊肌平面阻滞联合全凭静脉麻醉比例明显降低、静-吸复合麻醉和全凭静脉麻醉比例明显升高、出血量明显增加、术后Hb及术后钠离子浓度明显降低、术后第1天VAS疼痛评分明显升高（P＜0.05）。二元Logistic回归分析结果显示,年龄＞60岁（OR=1.099,95%CI 1.062～1.136）、酗酒史（OR=3.427,95%CI 1.859～6.315）、4级手术（OR=25.542,95%CI 1.878～347.342）、出血量＞431 ml（OR=1.005,95%CI 1.002～1.007）、术后第1天VAS疼痛评分＞2分（OR=1.797,95%CI 1.389～2.325）是脊柱手术患者POD的危险因素,BIS监测（OR=0.310,95%CI 0.144～0.669）、竖脊肌平面阻滞联合全凭静脉麻醉（OR=0.138,95%CI 0.051～0.373）、术后Hb＞122.8 g/L（OR=0.966,95%CI 0.943～0.993）是脊柱手术患者POD的保护因素。预测模型为Logit（P）=0.094×年龄+1.232×酗酒史-0.035×术后Hb+3.240×4级手术-1.171×BIS监测-1.980×竖脊肌平面阻滞联合全凭静脉麻醉+0.005×出血量+0.586×术后第1天VAS疼痛评分-9.648,该模型AUC为0.933（95%CI 0.917～0.948,P<0.001）,敏感性为90.5%,特异性为82.1%。
结论 年龄＞60岁、酗酒史、手术侵入类型（4级手术）、出血量＞431 ml以及术后第1天VAS疼痛评分＞2分是脊柱手术患者POD的独立危险因素。     

脑电双频指数的临床矛盾性评价

背景 1996年10月,美国食品药品管理局批准BIS监护仪用于临床监测镇静效应.BIS的临床使用减少了术中知晓,改善了患者术后恢复,提高了围手术期安全性,但临床应用发现,BIS数值和变化与临床表现有时并非一致(即矛盾性). 目的 对引起BIS矛盾性变化的原因进行阐述,以指导临床应用. 内容 原因可能与全身麻醉药的药理特点、作用部位、频谱干扰、特殊病理生理状态(包括低血糖、脑缺血、低血容量、神经功能障碍等)及年龄、手术方式、血管活性药物等诸多因素有关. 趋向 鉴于BIS的矛盾性,如何利用BIS监测或联合其他监测手段加强特殊人群麻醉管理,是需要积极思考的问题.     

BIS、AAI麻醉深度监测在七氟烷麻醉中的应用评价

目的：观察并分析围术期应用脑电双频谱指数（BIS）及听觉诱发电位指数（AAI）监测对七氟烷用量及对术毕苏醒时间和拔管时间的影响,并与传统以血流动力学指标来判断麻醉深度组相比较。方法：择期七氟烷全麻下行腹腔镜胆囊切除手术患者45例,ASAⅠ～Ⅱ级．随机分为三组：控制组（根据患者的血压来调节ETsevo。保持血压和心率波动在基础值的±15％）、AAI组（保持术中AAI值维持在15～20）、BIS组（保持术中BIS值维持在45～55）,每组15例。氧流量2L／min。于麻醉诱导前（基础值）．T1．T2、T3,T4、T5和苏醒即刻（T6）记录MAP．HR．SPO2、AAI、BIS和ETsevo,并记录苏醒时间和拔管时间。术毕1小时内取3个时点行OAA／S评分。结果：与AAI组和BIS组相比较,控制组麻醉维持期ETsevo大于其它两组（P〈0．05）。AAI组与BIS组的苏醒时间和拔管时间均较控制组短（p〈0．05）。但是术后1小时内各时点的OAA／S评分三组之间无明显差异。同时．AAI和BIS两组之间无差异。结论：将脑电监测运用于吸入麻醉能在很大程度上减少七氟烷用量,缩短患者麻醉苏醒时间和拔管时间．更有预见性的使用吸入麻醉。     

衰弱量表与衰弱表型评估对老年髋部骨折患者术后转归的预测作用

目的 比较衰弱量表与衰弱表型评估对老年髋部骨折患者术后转归的预测作用。
方法 2019年9月至2020年1月髋部骨折患者120例,男65例,女55例,年龄≥65岁,术前1 d分别采用衰弱量表和衰弱表型完成衰弱评估,依据两个量表各自评估的结果将患者分为：非衰弱期、衰弱前期和衰弱期,通过κ检验比较两种方法的一致性,并通过χ2检验确定衰弱与术后转归各项指标之间的关系。
结果 采用衰弱量表和衰弱表型检出老年髋部骨折患者术前衰弱期的比例分别为15.0%、22.5%,一致性检验κ值为0.55（95%CI 0.42～0.67）。根据衰弱量表评估结果,衰弱期患者术后总并发症（RR=4.5,95%CI 0.9～21.5）、术后住院时间超过5 d（RR=3.5,95%CI 1.0～12.2）和PACU停留时间超过60 min（RR=6.9,95%CI 1.2～40.1）的发生风险明显高于非衰弱期患者,衰弱前期患者术后住院时间超过5 d的发生风险明显高于非衰弱期患者（RR=2.7,95%CI 1.0～7.0）。根据衰弱表型评估结果,衰弱前期患者术后总并发症的发生风险明显高于非衰弱期患者（RR=4.7,95%CI 1.0～22.9）,衰弱期患者PACU停留时间超过60 min的发生风险明显高于非衰弱期患者（RR=5.3,95%CI 1.0～28.6）。
结论 衰弱量表和衰弱表型作为老年髋部骨折术前衰弱评估工具,两者评估一致性中等,其中衰弱量表在预测术后转归方面更具优势。     

Processed EEG and patient outcome

The era of research evaluating clinical outcomes associated with processed electroencephalogram (EEG) monitoring began with the first randomized trial of bispectral index monitoring (BIS) performed as part of the clearance process for approving routine clinical use of the BIS monitor by the United States Food and Drug Administration. Subsequent to this initial investigation, numerous other clinical investigations have demonstrated that the use of processed EEG monitors as an additional method of patient assessment and an aid to anaesthetic dosing can decrease anaesthetic usage and hasten recovery times. Because of the presumed association between anaesthetic effect and EEG changes, it is not surprising that the additional research has focused on the impact of processed EEG monitoring on postoperative outcomes and perioperative safety especially the prevention of intraoperative awareness.     

区域阻滞麻醉与老年患者术后神经系统功能、病死率关系的研究进展

背景 区域阻滞麻醉应用于老年患者手术日益增多,其对老年患者术后神经系统功能、病死率的影响有待总结. 目的 通过文献综述,分析区域阻滞麻醉对老年患者术后神经系统、病死率的影响. 内容 讨论区域阻滞麻醉与老年患者术后神经系统功能,包括术后谵妄、认知功能障碍、脑卒中以及与病死率之间的关系. 趋向 区域阻滞麻醉可以减少老年患者术后肺部并发症,减少术后早期认知功能障碍,与全身麻醉相比,具有一定优势.区域阻滞麻醉是否能降低老年患者术后病死率、心血管并发症发生率、谵妄发生率、围手术期脑卒中发生率尚有待于进一步研究.     

Update on bispectral index monitoring

Since 1997, bispectral index (BIS; Aspect Medical Systems Inc., Natick, MA) has been in clinical practice and a wealth of experimental research has accumulated on its use. Originally, the device was approved only for monitoring hypnosis and has now received an indication for reducing the incidence of intraoperative awareness during anesthesia. Numerous studies have documented the ability of BIS to reduce intermediate outcomes such as hypnotic drug administration, extubation time, postoperative nausea and shortened recovery room discharge. Two recent large-scale outcome studies using BIS (one randomized controlled trial and one prospective, nonrandomized historical cohort study) identified an approximately 80% reduction in the incidence of recall after anesthesia. BIS provides clinicians with unique information that can be used to tailor hypnotic drug doses to individual patient requirements. BIS does not predict movement or hemodynamic response to stimulation, nor will it predict the exact moment consciousness returns. This review will also discuss other BIS applications including use in pediatrics, intensive care and for procedural sedation. Some limitations exist to the use of BIS and it is not useful for some individual hypnotic agents (ketamine, dexmedetomidine, nitrous oxide, xenon, opioids). BIS technology is moving out of the operating room and into diverse environments where conscious and deep sedation are provided. Anesthesiologists need to be actively involved in promoting patient safety and helping transition this technology into broader use.     

Availability of anesthetic effect monitoring: utilization, intraoperative management and time to extubation in liver transplantation

Titration of volatile anesthetics to anesthetic effect monitoring using the bispectral index (BIS) has been shown to decrease anesthetic requirements and facilitate recovery from anesthesia unrelated to liver transplantation (OLT). To determine whether availability of such monitoring influences its utilization pattern and affect anesthetic care and outcomes in OLT, we conducted a retrospective analysis in recipients with and without such monitoring. We evaluated annual BIS utilization over a period of 7 years, and compared 41 BIS-monitored patients to 42 controls. All received an isoflurane/air/oxygen and opioid-based anesthetic with planned postoperative ventilation. Data collection included age, body mass index (BMI), gender, Model for End-stage Liver Disease (MELD) score, and time to extubation (TtE). Mean preanhepatic, anhepatic, and postanhepatic end-tidal isoflurane concentrations were compared, as well as BIS values for each phase of OLT using the Kruskal-Wallis and Wilcoxon signed-rank tests, respectively. The use of anesthetic effect monitoring when available increased steadily from 15% of cases in the first year to almost 93% by year 7. There was no significant difference in age, gender, BMI, MELD, or TtE between groups. The BIS group received less inhalational anesthetic during each phase of OLT compared to the control group. However, this difference was statistically significant only during the anhepatic phase (P = .026), and was clinically not impressive. Within the BIS group, the mean BIS value was 38.74 ± 5.25 (mean ± standard deviation), and there was no difference for the BIS value between different transplant phases. Availability of anesthetic effect monitoring as an optional monitoring tool during OLT results in its increasing utilization by anesthesia care teams over time. However, unless integrated into an intraoperative algorithm and an early extubation protocol for fast tracking of OLT recipients, this utilization does not appear to provide a clinical benefit but instead drives cost.     

Different benefit of bispectal index (BIS) in desflurane and propofol anesthesia

BACKGROUND: Bispectal index (BIS) monitoring may reduce drug usage and hasten recovery in propofol and inhalation anesthesia. The faster emergence profile of desflurane may reduce the effect of BIS monitoring on recovery from desflurane compared with propofol. This study compared hypnotic drug usage, recovery, patient satisfaction and incidence of inadequate sedation in BIS monitored and nonmonitored women anesthetized with desflurane or propofol. METHODS: One hundred and sixty patients scheduled for elective gynecological surgery were randomly assigned to desflurane or propofol anesthesia with and without BIS monitoring. Fentanyl, vecuronium and remifentanil were administered according to clinical criteria. The BIS monitor was used in all patients, but the monitor screen was covered in the controls. A BIS level between 45 and 55 was targeted in the BIS monitored patients whereas depth of anesthesia was assessed by clinical criteria in the controls. RESULTS: The mean (SD) desflurane MAC-hours administered with and without BIS were 0.70 (0.15) and 0.76 (0.12), respectively, resulting in extubation times of 6.5 (4.1) and 8.3 (6.1) min. (NS). Bispectal index monitoring was associated with improved patient satisfaction, reduced postoperative nausea and antiemetic drug requirement, and fewer episodes with sustained BIS levels > 60. The mean (SD) propofol infusion rates were 6.0 (1.4) and 6.6 (0.9) mg kg(-1)h(-1) with and without the BIS monitor (P = 0.023), resulting in mean (SD) extubation times of 6.8 (4.6) and 10.5 min (5.9), respectively (P < 0.05). CONCLUSION: Bispectal index monitoring reduced propofol usage and hastened recovery after propofol anesthesia, whereas in desflurane anesthesia it was associated with improved patient satisfaction, probably because of decreased postoperative nausea and fewer episodes of inadequate hypnosis.     

脑电双频指数用于开颅术后患者意识障碍预测

目的探讨开颅术后早期脑电双频指数(BIS)监测对患者远期意识状态预测的准确性,指导护士早期判断患者意识状态。方法对63例开颅术后延迟苏醒拔管患者,记录术后6 h内每小时BIS监测值(BISmax)、道格拉斯昏迷量表中的语言或疼痛刺激体动反应评分(GCS-M)及术后24 h意识状态。根据患者术后24 h是否清醒分组,计算两组BISmax、GCS-M及BISmax对术后24h意识障碍的预测概率(PK)。结果术后24 h清醒患者57例,未清醒6例;清醒者GCS-M评分均为6分,术后6 h内BISmax预测术后24 h意识障碍的PK值为0.69~0.86。结论监测BIS可作为开颅术后患者意识状态的辅助预测方法。     

Bispectral Index compared to Ramsay score for sedation monitoring in intensive care units

AIM: Continuous monitoring is of paramount importance in order to obtain a correct level of sedation in ICU patients. Clinical scoring systems, although simple and inexpensive, are often inadequate in evaluating the patient level of consciousness. Among instrumental tools for sedation monitoring, Bispectral Index (BIS) is now widely used due to its reliability and applicability. Nevertheless some doubts still exist regarding its usefulness in ICU. METHODS: Sedation, obtained with propofol or midazolam, was monitored with Ramsay scale and BIS in 40 patients admitted in ICU for postoperative monitoring after major abdominal or vascular surgery. A correlation between Ramsay score and BIS values was searched using Pearson test. RESULTS: A good correlation between Ramsay score and BIS values was observed. At the deeper levels of sedation a wide range of BIS values corresponds to Ramsay score 6, indicating various levels of central nervous system depression that are not identified by clinical evaluation. CONCLUSIONS: BIS monitoring is useful in ICU patients and allows a finest differentiation of sedation level in deeply sedated ICU patients.