Modified Transcranial Electromagnetic Motor Evoked Potential Obtained with Train-of-four Monitor for Scoliosis Surgery

脊椎矯正手術中經顱骨腦皮質電磁刺激並用Train-of four Monitor來監視運動神經誘發電位

林必盛(Bih-Chern Lin) ； 陳英和(Ing-Ho Chen)

《Acta Anaesthesiologica Sinica》 36卷4期 (1998/12) Pp. 199-206

https://doi.org/10.6955/AAS.199812.0199

摘要

背景：在骨科的胸椎和腰椎手術當中，例如：駝背和脊椎側彎矯正手術，都需要做相當程度的脊椎體切除。因爲脊椎體的後面附近有脊椎的運動神經區，因此手術中有可能會傷害到脊椎的運動神經區，一般這一類手術都需要用運動神經誘發電位監視，使得手術時萬一到神經可以立即停止手術，或是改變矯正的程度，來避免手術後下肢可能造成癱瘓的情形。我們把Axon sentine1-4(上標 TM)機器上的Train-of four刺激訊號外送到Digitimer電磁刺激器的Input來啓動並且控制刺激的間隔時間和重覆的次數，再用Train-of four(TOF)監視器上的肌電圖電位變化來監視，以達到運動神經誘發電位監視同樣的效果。
方法：自從85年5月29日開始骨科病患需要做嚴重駝背矯正和脊椎側彎手術，並且會切除到脊椎體的時候，我們都會裝上感覺神經誘發電位監視，和我們自行修改進拼裝的TOF monitor來監視手術過程。病人共有30人進行脊椎側彎矮正手術，手術時利用感覺神經誘發電位(SSEP)和經顱骨腦皮質電磁刺激運動神經誘發電位(tcMMEP)來作監視，病人年齡從12歲到55歲，男性4人、女性26人，分別爲17位idiopathic scoliosis，2位degenerative scoliosis，3位neurom-uscular scoliosis和1位hemivertebra scoliosis，其中有7位病人開2次手術。手術前神經檢查都列爲正常，感覺神經誘發電位監視是從手術開始至結束都持續進行，而運動神經誘發電位監視器是在麻醉開始、脊椎體切除、矯正調整和手術結束時進行。
結果：以上30例病曆的手術中訊號都一切正常，手術後也沒有下肢癱瘓。大多數病人矯正幅度高達70度以上，有4位病人達到90度，有1位病人達到100度，只有一位病人矯正僅到35度，在矯正幅度比較大時，才會在手術中做wake-up test總共做5個。手術中tcMMEP左腳onset latency爲27.32±0.45 msec，左腳為27.27±0.54 msec,amplitude右腳為3.52±1.97mV，左腳為4.05±1.22mV。麻醉中總共消耗fentanyl 118±25μg,sufentanil 73±51.5μg,propofol 908.33±349.49mg,vecu-ronium 10.48±3.48mg,atracurium 29.09±10.93mg, nitroglycerin 9.54±6.77mg。手術時間爲542.83±177.34min，失血量爲801.72±590.32ml。
結論：我們利用現有的機器Axon sentine-4(上標　TM)上的TOF功能，成功地在30例病患監視到運動神經誘發電位，所以我們會再進一步研究利用其他廠牌的TOF monitor，是否同樣能夠做到運動神經誘發電位監視的效果。

關鍵字

脊椎側彎 ； Train-of-four ； 運動神經誘發電位

並列摘要

Background: To monitor the spinal cord with somatosensory evoked potential (SSEP) is an accepted adjunct in the surgical correction of spinal deformities, but it does not directly assess the motor function. The use of motor evoked potential (MEP) has thus been introduced in an effort to meet this important need.
Methods: This preliminary report concerned 30 cases of scoliosis who underwent surgical correction under the surveillance of modified transcranial electromagnetic motor evoked potential (tcMMEP). Train-of four (TOE) stimulator output was connected to an electromagnetic stimulatoi The rate of repetition and interval of stimulation were controlled by TOF stimulator. Electromyographic (EMG) signals were obtained from the abductor hallucis muscle of both feet and interpreted as MEP activity. Anesthesia was made possible by propofol as a bask agent and isoflurane as supplement. Analgesia was obtained with sufentanil and fentanyl and amnesia enhanced by midazolam. Atracurium mixed with vecuronium in a ratio of 4:1 by weight in possible lowest dose was given to provide adequate muscle relaxation yet without the molestation of rapid reversal upon the request of wake-up test by the surgeon. Deliberate hypothermia and controlled hypotension were also applied since they did not interfere with the tcMMEP signals.
Results: Although no attempt was made to control the level of muscle relaxation at T1 more than 30%, tcMMEP signals could be obtainable during induction, at the time of surgical correction and at the end of the operation. TcMMEP onset latency was 27.32±0.45 msec on the left side and 27.27±0.54 msec on the right side. The amplitude was 3.52±1.97 mV on the left side and 4.05±1.22 mV on the right side.
Conclusions: The modified tcMMEP is so stable and convincing that research for similar modification is now undergoing with the other brand of TOF monitor by our team.

並列關鍵字

Scoliosis ； Train-of-four (TOF) ； Evoked potentials, motor