Pati Sandipan, McClain Lauren, Moura Lidia, Fan Yuan, Westover M Brandon
1 Department of Neurology, Massachusetts General Hospital, Boston, MA, USA.
2 Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.
Clin EEG Neurosci. 2017 Nov;48(6):422-427. doi: 10.1177/1550059417715389. Epub 2017 Jun 22.
Continuous EEG (cEEG) monitoring may help to identify the small percentage of adults with hypoxic-ischemic encephalopathy (HIE) who will regain consciousness if allowed sufficient time. However, the limited yield in this population has led some to question the cost-effectiveness cEEG monitoring in this population. We hypothesized that limited-montage cEEG could provide essentially the same neurophysiologic information at lower cost. In this proof of concept study, we aim to demonstrate the potentials of limited channel EEG in prognostication in postanoxic patients.
We retrospectively reviewed cEEG data from cases monitored at our institution with conventional 21-channel EEG over a 6-month period. Twenty-eight cases were identified in which patients with HIE underwent cEEG for at least 24 hours. Gold-standard findings were determined by conventional visual analysis of the full cEEG, and 2 independent electroencephalographers scored the same data using only limited-montage (4-channel) views. The sensitivity and specificity of limited-montage cEEG review were compared with conventional analysis. We also compared the relative costs of conventional and limited-montage EEG.
Using 4-channel limited montage cEEG, reviewers were able to classify accurately background continuity (in 88%), background amplitude (in 81%), maximum background frequency (in 70%), periodic epileptiform discharges, including a seizure (in 92%) and sporadic discharges (in 91%). All epileptiform features were detected with greater than 90% sensitivity and specificity. Eye movement artifact seen over bifrontal electrodes gave false positive detections of periodic epileptiform discharges in 31% of cases.
Limited-channel continuous EEG monitoring can provide meaningful electrophysiological data that can be used for prognostication in postanoxic comatose patients. Limited channel EEG can be a cost-effective alternative to conventional EEG monitoring in post-anoxic comatose patients.
持续脑电图（cEEG）监测可能有助于识别一小部分患有缺氧缺血性脑病（HIE）的成年人，如果给予足够时间，他们可能会恢复意识。然而，该人群中监测结果的有限收益导致一些人质疑cEEG监测在该人群中的成本效益。我们假设有限导联cEEG能够以更低的成本提供基本相同的神经生理学信息。在这项概念验证研究中，我们旨在证明有限通道脑电图在缺氧后患者预后评估中的潜力。
我们回顾性分析了在我们机构进行常规21通道脑电图监测6个月期间的病例的cEEG数据。确定了28例HIE患者接受cEEG监测至少24小时的病例。通过对完整cEEG进行常规视觉分析确定金标准结果，两名独立的脑电图专家仅使用有限导联（4通道）视图对相同数据进行评分。将有限导联cEEG评估的敏感性和特异性与常规分析进行比较。我们还比较了常规脑电图和有限导联脑电图的相对成本。
使用4通道有限导联cEEG，评估者能够准确分类背景连续性（88%）、背景振幅（81%）、最大背景频率（70%）、周期性癫痫样放电，包括癫痫发作（92%）和散在放电（91%）。所有癫痫样特征的检测敏感性和特异性均大于90%。双额电极上出现的眼球运动伪差在31%的病例中导致周期性癫痫样放电的假阳性检测。
有限通道持续脑电图监测可以提供有意义的电生理数据，可用于缺氧后昏迷患者的预后评估。有限通道脑电图可以作为缺氧后昏迷患者常规脑电图监测的一种具有成本效益的替代方法。
