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Semin Neurol 2006; 26(4): 403-412
DOI: 10.1055/s-2006-948321
Copyright © 2006 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA.

Electrophysiological Prognostication and Brain Injury from Cardiac Arrest

Peter W. Kaplan1
  • 1Department of Neurology, Johns Hopkins Bayview Medical Center, Baltimore, Maryland
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Publication History

Publication Date:
10 August 2006 (online)

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ABSTRACT

Anoxic coma after cardiorespiratory arrest warrants precocious investigation to establish probable outcome. Electroencephalogram (EEG) may uncover subclinical seizures; EEG grades have provided accurate prognosis of poor and favorable outcomes, but are weakest in those patients in between. Somatosensory evoked potentials now have proven benefit in accurately establishing a poor outcome (death or persistent vegetative state) when cortical responses (N20) are absent. These studies are particularly helpful when clinical examination of coma, early on, might yield uncertain prognosis (i.e., when brain stem reflexes are present). Combining clinical examination with electrophysiology has increasingly yielded multimodality approaches to early prognostication of coma after cardiorespiratory arrest, with more recent studies using event-related and middle-latency potentials showing promise for distinguishing good outcome (to consciousness), from awake but vegetative states. Further studies are warranted for this multimodality approach which, hopefully, may yield more widespread practical use of these testing modalities.

KEYWORDS

Electroencephalography - somatosensory evoked potentials - cardiorespiratory arrest - anoxic coma - prognosis - outcome

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Peter W KaplanM.B. B.S. F.R.C.P. 

Department of Neurology, Johns Hopkins Bayview Medical Center, B Building

1 North, Room 125, 4940 Eastern Avenue, Baltimore, MD 21224