环杓侧肌肌电图用于喉返神经功能的术中评估

目的 探讨经环甲肌置入双极电极监测环杓侧肌复合肌肉动作电位以指导术中探查解剖显露喉返神经并评估其功能的有效性、可行性.方法 临床病例分为神经监测组及对照组,通过针刺电极记录环杓侧肌复合肌肉动作电位,间断刺激暴露或未暴露的喉返神经,对颈丛麻醉下甲状腺手术中喉返神经功能进行监测,对照组则常规显露喉返神经.结果 监测组与非监测组在手术时间(125.54 ±42.23 min比107.30±39.36 min)、术后住院天数(5.14 ±1.44d比5.05 ±1.31 d)相比差异均无统计学意义(均P ＞0.05).32侧神经在暴露前利用监护仪描记出解剖走行,其中25侧继续解剖暴露神经,神经暴露后走行与未暴露前解剖走行完全一致,未暴露前RIN刺激阈值(2.23±0.57) mA,暴露后刺激阈值(0.44±0.20) mA,差异有统计学意义(P＜0.01),未暴露前诱发EMG波幅(307.98±253.47) μV,暴露后诱发EMG波幅(234.36±142.18)μV,差异无统计学意义(P＞0.05).结论 颈丛麻醉下监测环杓侧肌肌电图探查解剖暴露喉返神经、术中评估喉返神经功能是一项安全、有效、可行的方法.     

甲状腺手术致喉返神经损伤的修复

目的探讨甲状腺手术致喉返神经损伤的修复时机及预后,进一步提高修复效果。方法对１２例甲状腺手术致喉返神经损伤者采用了不同术式及不同时机神经修复或再支配术,其中即刻手术６例,延期手术６例;喉返神经直接吻合５例,膈神经与喉返神经远侧断端吻合选择性支配环杓后肌,同时颈袢分支胸骨舌骨肌支与喉内收肌支吻合选择性支配喉内收肌１例,颈袢主支与喉返神经内收肌支吻合３例,颈袢胸骨甲状肌蒂植入左环杓后肌３例。结果术后随访６个月以上。即刻手术较延期手术效果好,选择性神经修复术较喉返神经直接吻合好,且延期手术１２个月以上效果较差。结论甲状腺手术致喉返神经损伤应尽早修复,最晚不超过１年。     

甲状腺及甲状旁腺手术中迷走神经及喉返神经适宜刺激电流强度的探讨

目的探索甲状腺及甲状旁腺手术中迷走神经及喉返神经标准化监测各步骤的适宜刺激电流强度,以便更有效、更快速地对神经进行功能判断、定位、辨识及保护。方法前瞻性收集2013年5月至2013年8月期间在四川大学华西医院甲状(旁)腺疾病诊治中心接受同一主刀医师手术治疗并使用IONM的100例甲状腺或甲状旁腺疾病患者的临床资料,其中有损伤风险的喉返神经为186条。按标准化神经监测流程,用1~5 mA和1~3 mA的电流强度分别间接和直接刺激迷走神经及喉返神经,记录其肌电信号振幅以及监测刺激过程中患者的心率及血压变化情况,来寻求术中神经监测各阶段最适宜的电流强度。结果颈动脉鞘外监测迷走神经信号时,186条受测迷走神经中,1 mA时有109条(58.6%)有信号,得到稳定的肌电图及提示音,2 mA时有164条(88.2%)有信号,3 mA时有177条(95.2%)有信号,5 mA时有182条(97.8%)有信号;且在神经电刺激前后,患者的心率和血压均无明显变化。直接探测迷走神经时,1 mA监测V1信号时有2条(1.1%)无应答,V2时有9条(4.8%)无应答,而2 mA和3 mA的电流刺激时均得到了稳定的肌电信号。定位寻找喉返神经时,1 mA时有92条(49.5%)有信号,2 mA时有171条(91.9%)有信号,3 mA时有184条(98.9%)有信号。当鉴别喉返神经时,用2 mA的电流强度刺激,会出现电流旁传导而产生假象;以1 mA的电流刺激强度时,探针置于喉返神经邻近组织时则无肌电信号。鉴别RLN各分支时,用1 mA的电流强度刺激各神经分支,均可以得到肌电信号,其中入喉的主干分支振幅最高,支配食管及气管的分支肌电图振幅数值相近,为主干振幅数值的1/3~1/4。结论建议用5 mA的电流强度在颈鞘表面间接监测迷走神经以得到V1信号,可替代剖开颈鞘直接监测迷走神经的步骤;如鞘外监测V1信号失败,再解剖颈鞘,用3 mA的电流强度来直接监测迷走神经;用3 mA的电流强度寻找定位喉返神经;用1 mA的电流强度来鉴别喉返神经及其食管分支、气管分支、血管等。     

喉上神经外支监测在咽下缩肌入路甲状腺手术中的应用

目的:探讨在咽下缩肌入路甲状腺手术中,通过实时神经监测技术避免喉上神经外支损伤的可行性.方法:2010年3月-2011年4月18例甲状腺手术患者,术中以喉上神经外支受电流刺激后可产生环甲肌收缩活动作为阳性反应,定位喉上神经外支与咽下缩肌的关系后,切断咽下缩肌,经其后方显露喉返神经行程,行甲状腺腺叶切除8例,甲状腺腺叶切除加对侧次全切除8例,甲状腺全切2例.手术前后喉镜监测喉上、喉返神经功能.结果:患者均顺利游离显露咽下缩肌后方喉返神经,术后1例(5.6％)出现短暂性发音低沉,随访6个月后完全缓解.余患者无明显咳呛、发音低沉、失声等神经损伤表现.结论:经咽下缩肌入路甲状腺手术中,实时神经监测技术有利于保护喉上神经功能.     

术中神经监测技术在复杂甲状腺手术中的应用

目的 探讨应用术中神经监测技术（intra operative neuromonitoring,IONM）,以减少复杂甲状腺手术喉返神经损伤。方法 吉林大学中日联谊医院甲状腺外科2009年3~7月对132例复杂甲状腺手术病人,共186支高风险喉返神经行术中神经监测。在甲状腺切除前后分别探测迷走神经及喉返神经肌电信号。甲状腺手术前后常规检查声带活动度。结果 除术前声带麻痹4例,余182支喉返神经均可在甲状腺切除后测得明显肌电信号,未发生缝合切口前神经肌电信号消失,提示神经电传导功能良好。精确检出非返性喉返神经2例。结论 术中喉返神经监测使喉返神经显露更加便捷,更加确切,并可验证喉返神经功能完整性。在高风险、复杂甲状腺术中应用神经监测是降低喉返神经损伤率的一种重要辅助措施。     

新型适配器在术中喉返神经功能持续监测中的临床应用：附329例报告

目的:探讨应用自主研发的神经监测适配器对术中喉返神经功能持续监测的临床作用与意义。方法:对笔者两家单位甲状腺外科共计329例甲状腺(旁腺)患者行加用适配器的术中神经功能持续监测。结果:术中共484根喉返神经均寻找顺利,发现8条神经肌电信号丢失后及时处理,术后行喉镜检查2例出现声带麻痹,2周内恢复正常。结论:甲状腺手术中加用适配器的喉返神经功能持续监测技术能有效地保护喉返神经,安全、可行。     

环杓后肌在膈神经再支配后收缩特性的研究

采用膈神经与喉返神经吻合,术后测定环杓后肌收缩功能,观察膈神经再支配环杓后肌的收缩功能。证明膈神经能较好地恢复环杓后肌的收缩特性,主要表现在再神经支配后的环杓后肌的收缩张力及收缩时间与健侧无差异。进一步证实了膈神经再支配环杓后肌较为合适。     

显微外科修复尿道下裂术后尿道皮肤瘘

目的 探讨喉返神经修复手术治疗声带麻痹的效果及损伤的修复时机对预后的影响。方法 采用了不同术式及不同时机施行神经修复手术治疗声带麻痹１９例（单侧１４例，双侧５例０，其中即刻手术６例、延期手术１３例，喉返神经直接吻合５例、膈神经与喉返神经远侧断端吻凳时颈拦胸骨舌骨肌支与喉内收肌支吻合１例、颈袢主支与喉返神经内收肌支吻合８例、颈袢胸骨 肌蒂填植入左环杓后肌５例。结果 １９例均有不同神经再支配，且即刻手     

喉返神经探测仪实时监测在再次甲状腺手术中的应用

目的探讨喉返神经探测仪在甲状腺再次手术中实时神经监测的使用方法及应用价值。方法对101例甲状腺再次手术患者在全麻手术中使用喉返神经探测仪(NIM-Response肌电图监测仪)进行实时喉返神经监测,显露喉返神经。结果 101例再次手术患者中,共探测喉返神经192条,均成功显露;10例术前已证实有单侧喉返神经损伤的患者,术中未刻意探查该侧喉返神经。192条喉返神经中190条完整保护无损伤,2条因肿瘤侵犯予以切除。术后患者无声嘶加重和呼吸困难。结论使用喉返神经探测仪能较好地帮助发现和保护喉返神经,减少医源性喉返神经损伤发生率,值得在甲状腺再次手术中应用。     

术中神经监测技术在甲状腺手术中的应用与进展

喉返神经损伤是甲状腺手术较常见及最严重的并发症,尤其在复杂甲状腺手术及再次甲状腺手术中,因解剖层次不清、喉返神经解剖变异等所导致的喉返神经损伤机会加大。术中神经监测(IONM)是应用电生理技术监测术中神经功能完整性的一种技术,近年来研究显示,甲状腺手术中喉返神经IONM较常规暴露喉返神经能明显降低暂时性及永久性喉返神经损伤率。笔者就有关喉返神经IONM在甲状腺手术中的应用与进展进行综述。     

Compound Muscle Action Potentials and Spontaneous Electromyography Can be Used to Identify and Protect the Femoral Nerve During Resection of Large Retroperitoneal Tumors

Background Resection of large retroperitoneal neoplasms may injure the femoral nerve, thereby causing a permanent neurological deficit. We used electrical neurophysiological monitoring to identify, map, and preserve the femoral nerve during surgical resection to reduce the risk of neurological deficit. Methods Seven patients with retroperitoneal neoplasms underwent eight resections. Compound muscle action potentials (CMAPs) were recorded from needle electrodes placed in the iliacus, quadriceps, and sartorius muscles. Spontaneous electromyography (EMG) was contnuously monitored from the same muscle groups. A handheld monopolar stimulator was used to elicit evoked EMG responses to identify and map the course of the femoral nerve. A stimulating strength of 10 mA was used to map the nerve. The stimulation threshold was tested after neoplasm resection to predict postoperative femoral nerve function. Results Electrical stimulation with CMAP recording and a stimulating strength of 10 mA successfully localized the femoral nerve in six cases. Monitoring with a stimulating threshold between 0.6 and 1.6 mA predicted postoperative femoral nerve preservation after tumor resection in four of the six cases. Conclusion Neurophysiological monitoring using CMAP and spontaneous EMG can protect the femoral nerve during resection of large retroperitoneal neoplasms.     

Electrophysiologic evaluation of lumbosacral single nerve roots using compound muscle action potentials

Transcutaneous electrical stimulation applied to the vertebral column produces compound muscle action potentials (CMAPs) from the leg muscles. Using this method, we evaluated the efferent pathways of the lumbosacral nerve roots. The subjects were 26 healthy volunteers and 31 patients with lumbar disc herniation (LDH). CMAP recordings were obtained from the bilateral vastus medialis, tibialis anterior, extensor digitorum brevis, and abductor hallucis muscles using low-output-impedance stimulation. In normal subjects, the CMAP latency increased linearly with the distance between the stimulating electrode and the recording electrode, with little difference in latency between the left and the right sides in each subject. The CMAP amplitude was significantly lower in the patients with LDH, and the latency was also prolonged when the stimulating electrode was placed above the lesion. This technique may thus be a useful noninvasive method for assessing lumbosacral nerve root function in patients with LDH.     

Intraoperative electrophysiological monitoring for functional preservation of the cauda equina during lumbosacral surgery]

Adequate electrophysiological techniques to monitor function of the cauda equina have been proposed for surgery in patients with lumbosacral lipoma or myeloschisis. Motor fibers were identified by electrical stimulation in the operating field with bipolar rectangular impulses of 200 mu sec duration at 2 Hz under 5 mA and compound muscle action potentials (CMAPs) recorded from the leg and anal muscles. By recording CMAPs from the tibialis anterior, the biceps femoris, the gastrocnemius, and the external anal sphincter muscles, all of the roots from the fourth lumbar to the fourth sacral segment were continuously monitored. To spare recording channels, recordings were obtained from the right versus the left side. In our institute, 5 patients have undergone lumbosacral surgery while using this monitoring system, and the results indicated that there was no postoperative neurological exacerbation in any of the cases. According to a combination of the CMAPs produced by stimulation, the segment of the stimulated motor root could be identified electrophysiologically. Monitoring of somatosensory evoked potentials was not performed because this would have required too much time and would have prolonged surgery. However, some sensory fibers, which appeared to be posterior roots of the cauda equina on intraoperative inspection, could be identified indirectly with CMAPs recording because of current spreading from the stimulation to motor fibers.     

Continuous EMG recordings and intraoperative electrical stimulation for identification and protection of cervical nerve roots during foraminal tumor surgery

OBJECTIVE: Spinal cord function is now routinely monitored with somatosensory evoked potentials (SEPs) and motor evoked potentials (MEPs) during surgery for intraspinal cervical dumbbell and foraminal tumors. However, upper extremity nerve roots are also at risk during these procedures. Anatomic relations are frequently difficult to interpret because the nerve roots may be displaced by the tumor. We used electrical stimulation with compound muscle action potential (CMAP) recordings at multiple sites to identify the location and course of the involved nerve root and to provide real-time information regarding the functional status of the roots to predict postoperative outcome. METHODS: Ten patients were monitored during surgery for cervical dumbbell or foraminal tumors. SEPs and MEPs were monitored as a routine procedure. CMAPs were recorded from needle electrodes placed in the deltoid, biceps, triceps, and flexor carpi ulnaris muscles. Spontaneous electromyography (EMG) muscle activity was also continuously monitored. A handheld monopolar stimulation electrode was used to elicit evoked EMG responses to identify and trace the course of nerves in relation to the tumor. In four patients, the stimulation threshold was tested before and after tumor resection to predict postoperative nerve root function. RESULTS: Electrical stimulation with CMAP recording was successful in localizing nerve roots during tumor resection in all 10 patients. Monitoring predicted postoperative nerve root preservation after tumor removal in each case. It was possible to identify either by using low-level stimulation (<2.0 V) or by observing changes in spontaneous EMG amplitude if activation was present during surgical dissection. The monitoring of spontaneous muscle activity in response to direct or indirect surgical manipulation during tumor resection also provided continuous assessment of nerve root function and identified any physiologic disturbance induced by surgical manipulation. CONCLUSIONS: Electrical stimulation in the operating field and recording of CMAPs facilitated nerve root identification and predicted postoperative function during dissection and separation from ligamentous or neoplastic tissue in 10 patients. Electrical stimulation might also be useful to predict postoperative preservation of function when nerve root sacrifice is necessary and no motor response is detected intraoperatively.     

On the applicability of two different stimulation techniques for intra-operative peroneal nerve conduction testing.

Dysfunction of the peroneal nerve is an important complication of knee surgery. We compared two monitoring procedures of peroneal nerve function during a standardized operation, a closing wedge high tibial osteotomy. For two types of stimulation the evoked compound motor unit action potentials (CMAPs) were recorded on the tibialis anterior muscle. We used direct perineural electrical stimulation of the common peroneal nerve distal to the cuff (dCMAPs) after nerve identification in the surgical field. Additionally, magnetic stimulation of the sacral plexus proximal to the cuff (pCMAPs) was performed. It was found that dCMAPs were recorded during almost one hour of tourniquet time whereas the pCMAPs were blocked after 25-30 min in 9 out of 11 cases. On the other hand, the CMAP obtained after proximal stimulation exhibited a latency shift with tourniquet yielding an indicator of ischaemic changes present beneath and distal to the tourniquet cuff. In conclusion, different applicabilities of both stimulation techniques under tourniquet conditions were demonstrated.     

Acute respiratory failure after deep cervical plexus block for carotid endarterectomy as a result of bilateral recurrent laryngeal nerve paralysis

We report about a case of acute respiratory distress (73-year-old female), which occurred minutes after a deep cervical plexus block (40 ml ropivacaine 0.5%) for carotid endarterectomy (CEA) and required immediate endotracheal intubation of the patient's trachea and consecutive mechanical ventilation. Subsequently, CEA was performed under general anaesthesia (TIVA) with continuous monitoring by somatosensory-evoked potentials. After a period of 14 hours, the endotracheal tube could be removed, the patient being in fair respiratory, cardiocirculatory and neurological conditions. Retrospectively, acute respiratory distress was caused by a combination of ipsilateral plexus blockade-induced and pre-existing asymptomatic contralateral recurrent laryngeal nerve (RLN) paralysis confirmed by a postoperative ENT-check and related to previous thyroid surgery more than 50 years ago. RLN paralysis, often being asymptomatic, represents a typical complication of thyroid and other neck surgery with reported incidences of 0.5-3%. Therefore, a thorough preoperative airway check is advisable in all patients scheduled for a cervical plexus block. Particularly in cases with a history of respiratory disorders or previous neck surgery a vocal cord examination is recommended, and the use of a superficial cervical plexus block may lower the risk of respiratory complications. This may prevent a possibly life-threatening coincidence of ipsilateral plexus blockade-induced and pre-existing asymptomatic contralateral RLN paralysis.     

Effect of brachial plexus co-activation on phrenic nerve conduction time

BACKGROUND: Diaphragm function can be assessed by electromyography of the diaphragm during electrical phrenic nerve stimulation (ES). Whether phrenic nerve conduction time (PNCT) and diaphragm electrical activity can be reliably measured from chest wall electrodes with ES is uncertain. METHODS: The diaphragm compound muscle action potential (CMAP) was recorded using an oesophageal electrode and lower chest wall electrodes during ES in six normal subjects. Two patients with bilateral diaphragm paralysis were also studied. Stimulations were deliberately given in a manner designed to avoid or incur co-activation of the brachial plexus. RESULTS: For the oesophageal electrode the PNCT was similar with both stimulation techniques with mean (SE) values of 7.1 (0.2) and 6.8 (0.2) ms, respectively (pooled left and right values). However, for surface electrodes the PNCT was substantially shorter when the brachial plexus was activated (4.4 (0.1) ms) than when it was not (7.4 (0.2) ms) (mean difference 3.0 ms, 95% CI 2.7 to 3.4, p<0.0001). A small short latency CMAP was recorded from the lower chest wall electrodes during stimulation of the brachial plexus alone. CONCLUSIONS: The results of this study show that lower chest wall electrodes only accurately measure PNCT when care is taken to avoid stimulating the brachial plexus. A false positive CMAP response to phrenic stimulation could be caused by inadvertent stimulation of the brachial plexus. This finding may further explain why the diaphragm CMAP recorded from chest wall electrodes can be unreliable with cervical magnetic stimulation during which brachial plexus activation occurs.     

臂丛颈7神经根支配主要代表肌的电生理研究

目的 通过电生理检测分析臂丛颈,神经根的主要代表肌.方法 选择16例臂丛神经根性撕脱伤行健侧颈7神经根移位的患者,术中采用电生理检测,对颈7神经根支配肌的波幅进行分析,确定颈7神经根的主要代表肌.结果 电生理检测表明背阔肌与肱三头肌长头均可较好地代表颈7神经根的功能.尤其是肱三头肌长头在所有16例患者的检测中,刺激颈7神经根所得复合肌肉动作电位(CMAP)波幅值均明显大于其余神经根所得波幅值;而背阔肌有4例(占25.0%),在刺激颈6神经根时所得CMAP波幅值与颈,神经根接近.结论 将肱三头肌长头、背阔肌作为定位颈,神经根的代表肌更具有合理性与科学性.     

Electromyographic assessment of ulnar nerve motor block induced by lidocaine

Study Objective: To determine the differences in the onset time and duration of motor block produced by lidocaine 1% and lidocaine 2% via a quantitative and objective method, the measurement of compound muscle action potentials (CMAPs).

Study Design: Prospective study.

Setting: Main operating rooms of a university hospital.

Patients: 20 consecutive patients undergoing surgery not requiring intraoperative muscle relaxation.

Interventions: General anesthesia with unilateral ulnar nerve block was administered. In patients’ nondominant (experimental) arms, an insulated block needle was placed adjacent to the ulnar nerve at the wrist while continuous nerve stimulation was delivered to ensure its proper placement. Through this needle, lidocaine 1% or lidocaine 2% was injected. The dominant (control) arm received no injection.

Measurements and Main Results: Monitoring of ulnar nerve-evoked CMAPs was performed simultaneously on both arms. Ulnar nerve function was assessed at baseline and then at 10-second intervals by automatically measuring the amplitude of the evoked CMAPs on a two-channel electromyogram. The mean (± SEM) baseline CMAP amplitude prior to injection of lidocaine 1% was 3.10 ± 0.87 mV and 3.06 ± 0.89 mV for the experimental and control ulnar nerves, respectively (p = NS); for lidocaine 2%, baseline CMAP amplitude was 3.58 ± 1.39 mV and 3.70 ± 1.46 mV, respectively (p = NS). Over the course of the study, the control CMAP amplitude varied by <12%. At the experimental ulnar nerve, 90% CMAP decrease after injection of lidocaine 1% and lidocaine 2% occurred 7.5 ± 2 minutes and 5 ± 1.5 minutes, respectively (p = NS), whereas maximal blockade was achieved after 15 ± 3 minutes and 11 ± 5 minutes, respectively (p = NS). Recovery of CMAP to 90% of baseline occurred 184 ± 31 minutes after injection of lidocaine 1% and 248 ± 30 minutes following lidocaine 2% (p = NS).

Conclusion: The present study describes a technique that can be used in vivo to objectively measure the speed of onset and duration of local anesthetic-induced motor blockade. Although statistically not different, lidocaine 2% demonstrated a faster onset and longer duration of ulnar nerve motor block than lidocaine 1%.     

应用电生理检测肌皮神经肱肌肌支在神经根的定位

目的 探讨应用电生理检测肌皮神经肱肌肌支在神经根的定位,为肱肌肌支移位术的临床应用寻求理论依据.方法 选择30例臂丛神经损伤行健侧C7移位的患者,年龄16～50岁,平均[(28.9±7.7)岁,-x±s,下同],术中暴露健侧正常的臂丛神经,运用意大利ESAOTE的Reposer四道程肌电诱发电位仪,分别刺激C5～T1神经根,在肱肌记录诱发电位的潜伏期及波幅.结果 30例健侧C7移位者术中电生理检测,刺激臂丛神经根时,其中C529例、C630例、C728例记录到肱肌运动电位,而刺激C8、T1仅有6例记录到较小的肱肌运动电位.C5、6、7运动电位的潜伏期和波幅分别为(6.32±1.50)ms、(6.51±1.36)ms、(6.99±1.33)ms和(4.87±4.43)mV、(5.65±4.76)mV、(0.90±2.29)mV,其中以C6的波幅最大,C5次之,C7波幅较小,提示C5、6支配肱肌的神经纤维数可能最多.结论 肱肌主要接受来自C5、6神经纤维的支配,该肌支移位至正中神经(骨间前神经)是可行及有效的,同时该方法为今后临床研究周围神经的定位提供了检测手段.