Nau H E, Hess W, Pohlen G, Marggraf G, Rimpel J
Anaesthesist. 1987 Mar;36(3):116-25.
Intraoperative neuromonitoring, especially evoked potential monitoring, has gained interest in recent years for both the anesthesiologist evaluating cerebral function and the neurosurgeon wishing to avoid neuronal lesions during intracranial operations. Before evoked potential monitoring can be introduced as a routine method of intraoperative management, experience with this method particularly in intensive care units, is imperative. We recorded evoked potentials with the Compact Four (Nicolet) and Basis 8000 (Schwarzer Picker International) computer systems. Preoperative derivations should be done with the same apparatus used intraoperatively and parameters of peri- and intraoperative derivations should not be changed. The patient's head must be fixed in a Mayfield clamp in order to avoid artefacts during trepanation. The possible artefacts due to apparatus, patient, or anesthesia are summarized in the tables. The derivations of evoked potentials should be supervised by a person who is not involved in the anesthesia or the surgical procedure; this condition may change in the future with full automatization of the recording technique and alarms. Good communication between surgeon, anesthesiologist, and neurophysiological assistant is a prerequisite. The modality is chosen in accordance with the affected neuronal system: visual-evoked potential (VEP) monitoring in the management of processes affecting the visual pathway, brain stem auditory-(BAER) and somatosensory-evoked potential (SSEP) monitoring in lesions affecting these pathways, in particular space-occupying lesions of the posterior fossa. VEP monitoring may be useful, but we observed alterations of the responses without changes in the level of anesthesia or manipulation of the visual pathways. In space-occupying processes of the cerebellopontine angle, BAER could not be developed in nearly all cases because the large underlying tumor had caused the disappearance of waves II-V. In these cases SSEP monitoring could be carried out. Despite these difficulties, evoked potential monitoring seems useful. We believe, however, that it is not routinely used in operating rooms at present because alterations of the responses can be due to different causes; for the neurosurgeon, the problem as to which interdependent degrees of alteration in evoked potentials are related to neuronal disturbances remains unsolved.
近年来，术中神经监测，尤其是诱发电位监测，引起了麻醉医生评估脑功能以及神经外科医生在颅内手术中希望避免神经元损伤的关注。在诱发电位监测能够作为术中管理的常规方法引入之前，尤其是在重症监护病房中积累该方法的经验是必不可少的。我们使用Compact Four（尼高力）和Basis 8000（施瓦泽皮克国际公司）计算机系统记录诱发电位。术前的导联应使用与术中相同的设备进行，围手术期和术中导联的参数不应改变。患者的头部必须用梅菲尔德头架固定，以避免开颅过程中出现伪迹。表格中总结了由设备、患者或麻醉导致的可能伪迹。诱发电位的导联应由不参与麻醉或手术操作的人员进行监督；随着记录技术和警报的完全自动化，这种情况未来可能会改变。外科医生、麻醉医生和神经生理助手之间良好的沟通是前提条件。根据受影响的神经元系统选择监测方式：在处理影响视觉通路的过程中进行视觉诱发电位（VEP）监测，在影响这些通路（特别是后颅窝占位性病变）的病变中进行脑干听觉诱发电位（BAER）和体感诱发电位（SSEP）监测。VEP监测可能有用，但我们观察到在麻醉水平未改变或未对视觉通路进行操作的情况下反应发生了改变。在桥小脑角占位性病变中，几乎在所有病例中都无法引出BAER，因为巨大的基础肿瘤导致了波Ⅱ - V消失。在这些病例中可以进行SSEP监测。尽管存在这些困难，诱发电位监测似乎是有用的。然而，我们认为目前它在手术室中并未常规使用，因为反应的改变可能由不同原因导致；对于神经外科医生来说，诱发电位改变的哪些相互依存程度与神经元干扰相关的问题仍未解决。
