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. 2023 Sep 1;40(6):553-561.
doi: 10.1097/WNP.0000000000000919. Epub 2022 Feb 3.

Developing a Standardized Approach to Grading the Level of Brain Dysfunction on EEG

Monica B Dhakar  1   2 , Zubeda B Sheikh  2   3 , Masoom Desai  4 , Raj A Desai  5 , Eliezer J Sternberg  6   7 , Cristina Popescu  8 , Jacqueline Baron-Lee  9 , Nishi Rampal  10 , Lawrence J Hirsch  2 , Emily J Gilmore  2 , Carolina B Maciel  2   9
Affiliations

Developing a Standardized Approach to Grading the Level of Brain Dysfunction on EEG

Monica B Dhakar et al. J Clin Neurophysiol. .

Abstract

Purpose: To assess variability in interpretation of electroencephalogram (EEG) background activity and qualitative grading of cerebral dysfunction based on EEG findings, including which EEG features are deemed most important in this determination.

Methods: A web-based survey (Qualtrics) was disseminated to electroencephalographers practicing in institutions participating in the Critical Care EEG Monitoring Research Consortium between May 2017 and August 2018. Respondents answered 12 questions pertaining to their training and EEG interpretation practices and graded 40 EEG segments (15-second epochs depicting patients' most stimulated state) using a 6-grade scale. Fleiss' Kappa statistic evaluated interrater agreement.

Results: Of 110 respondents, 78.2% were attending electroencephalographers with a mean of 8.3 years of experience beyond training. Despite 83% supporting the need for a standardized approach to interpreting the degree of dysfunction on EEG, only 13.6% used a previously published or an institutional grading scale. The overall interrater agreement was fair ( k = 0.35). Having Critical Care EEG Monitoring Research Consortium nomenclature certification (40.9%) or EEG board certification (70%) did not improve interrater agreement ( k = 0.26). Predominant awake frequencies and posterior dominant rhythm were ranked as the most important variables in grading background dysfunction, followed by continuity and reactivity.

Conclusions: Despite the preference for a standardized grading scale for background EEG interpretation, the lack of interrater agreement on levels of dysfunction even among experienced academic electroencephalographers unveils a barrier to the widespread use of EEG as a clinical and research neuromonitoring tool. There was reasonable agreement on the features that are most important in this determination. A standardized approach to grading cerebral dysfunction, currently used by the authors, and based on this work, is proposed.

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Conflict of interest statement

C. B. Maciel has received funding from Claude D. Pepper Older Americans Independence Center and American Heart Association. M. B. Dhakar has received funding from the National Institutes of Health (R21- NS116726-01), American Epilepsy Society, and research money for clinical trials from Marinus Pharmaceuticals and Parexel Biopharmaceuticals. She has received honoraria for consulting for Adamas Pharmaceuticals. N. Rampal serves as consultant at Alexion Pharmaceuticals. L. J. Hirsch has received consultation fees for advising from Accure, Aquestive, Ceribell, Marinus, Medtronic, Neurelis, Neuropace, and UCB; royalties from Wolters-Kluwer for authoring chapters for UpToDate-Neurology and from Wiley for coauthoring the book “Atlas of EEG in Critical Care,” by Hirsch and Brenner; and honoraria for speaking from Neuropace and Natus. E. J. Gilmore receives consulting fees from UCB and is a cofounder of IBA (uncompensated). In addition, she receives funding from the National Institutes of Health (R01 NS117904-01). The other authors have no conflicts of interest to disclose.

References

    1. Herman ST, Abend NS, Bleck TP, et al. Consensus statement on continuous EEG in critically ill adults and children, part I: indications. J Clin Neurophysiol 2015;32:87–95.
    1. Claassen J, Doyle K, Matory A, et al. Detection of brain activation in unresponsive patients with acute brain injury. New Engl J Med 2019;380:2497–2505.
    1. Sun H, Kimchi E, Akeju O, et al. Automated tracking of level of consciousness and delirium in critical illness using deep learning. NPJ Digit Med 2019;2:89.
    1. Hirsch LJ, LaRoche SM, Gaspard N, et al. American clinical neurophysiology society's standardized critical care EEG terminology: 2012 version. J Clin Neurophysiol 2013;30:1–27.
    1. Hirsch LJ, Fong MW, Leitinger M, et al. American clinical neurophysiology society's standardized critical care EEG terminology: 2021 version. J Clin Neurophysiol 2021;38:1–29.