ACNS Guideline: The New 2021 Critical Care EEG Terminology - ACNS Annual Course Lawrence J. Hirsch, MD, FACNS Michael W.K. Fong, MD

ACNS Guideline:
The New 2021 Critical Care EEG
         Terminology
         ACNS Annual Course

     Lawrence J. Hirsch, MD, FACNS
        Michael W.K. Fong, MD

Disclosures, relevant

⚫I  bill for continuous EEG monitoring (about 25%
  of my clinical billing)
⚫ I co-authored the Atlas of EEG in Critical Care
  (Hirsch and Brenner)
⚫ I borrowed some slides from the Critical Care
  EEG Monitoring Research Consortium, guideline
  co-authors, and Yale colleagues
 ⚫   Suzette Laroche, Nicholas Abend, Tammy Tsuchida, Sue Herman, Nicolas Gaspard, Brandon
     Westover, Suzette Laroche, Andres Rodriguez, Nicolas Gaspard, Emily Gilmore, Gamal Osman,
     Jiyeoun Yoo, Carolina Maciel, Nishi Rampal, Michael Fong, Markus Leitinger

Disclosures, unrelated

⚫ Consultant
  ⚫ Accure;   Aquestive; Ceribell; Eisai; Medtronic; Neuropace; UCB
⚫ Honoraria    for speaking
  ⚫ Neuropace;   Natus
⚫ Royalties
  ⚫ Wolters   Kluwer (UpToDate); Wiley

First version
        J Clin Nphysiol 2005
12 authors (10:2, M:F), all N. America

Second version: an official ACNS guideline
           (not just for research anymore)
                 J Clin Nphysiol 2013
     20 authors (13:7, M:F), 19 from N. America

Epilepsia, 2014

ACNS Nomenclature inter-rater
            agreement, round 3
                Gaspard et al, Epilepsia 2014
• Results: IRA statistics (j values) were almost perfect
  (90–100%) for seizures, main terms 1 and 2, the +S
  modifier, sharpness, absolute amplitude, frequency,
  and number of phases.
• Agreement was substantial for the +F and +R
  modifiers (66% and 67%), moderate for triphasic
  morphology (58%), and fair for evolution (21%).
• Significance: IRA for most terms in the ACNS critical
  care EEG terminology is high. These terms are
  suitable for multicenter research on the clinical
  significance of critical care EEG patterns.

American Clinical Neurophysiology
Society’s Standardized Critical Care EEG
              Terminology
                     J Clin Nphys, 2013

  CCEMRC Training Module (www.acns.org)
Lawrence Hirsch, Nicolas Gaspard, Brandon Westover, Suzette Laroche

                                                                      8

Development and Feasibility Testing of a Critical Care EEG
Monitoring Database for Standardized Clinical Reporting and
            Multicenter Collaborative Research
         Lee JW et al for the Crit Care EEG Monitoring Research Consortium.
                                    J Clin Nphys 2016

⚫   Supported by AES Infrastructure Award
⚫   The database and instruction manual were
    available as a free download to be used as a
    clinical data repository and report generating
    tool at: https://www.acns.org/research/critical-
    care-eegmonitoring-research-consortium-
    ccemrc

JAMA Neurol 2017

• 4772 patients undergoing CEEG in 3 centers (Emory,
  Yale, Brigham and Women’s)

Rodriguez Ruiz A et al, CCEMRC,
       JAMA Neurol 2017

Risk of acute seizures with LRDA vs LPDs
       Gaspard N et al, JAMA Neurology 2013

                                      63%
                                              57%

Other studies using the ACNS Terminology
• Higher frequency (especially >1.5 Hz), higher prevalence,
  longer duration, and having a “plus” modifier were all
  associated with a higher chance of acute seizures (Rodriguez-Ruiz
  A et al JAMA Neurol 2017; Pedersen GL et al, Clin Nphysiol 2013)
   – Whether stimulus-induced or not did not seem to matter (Rodriguez-Ruiz A et
     al JAMA Neurol 2017)

• “Triphasic morphology” was found NOT to be associated with a
  higher risk of metabolic encephalopathy or lower risk of seizures
  compared to non-triphasic GPDs (Foreman B et al, Clin Nphysiol 2016;
  O’Rourke D et al, Neurocrit Care 2016)
• Highly epileptiform bursts were predictive of seizure recurrence
  after weaning anesthetics (Thompson SA, Hantus S, J Clin Nphysiol 2016)
• Higher risk of later epilepsy if LPDs were more prevalent,
  longer duration or had a “plus” modifier (Pedersen GL et al, Clin
  Nphysiol 2013)

2021 Terminology has arrived!
        J Clin Nphysiol Jan 2021
   4,123 authors, 9 continents, 2 planets
      30 authors (22:8, M:F), 8 countries, 4 continents

   Thanks to all co-authors. Special thanks to Michael
   Fong and Markus Leitinger for helping with the
   publication, diagrams, figures, EEG samples and slides

Good news
⚫ Most prior terms and definitions remain
  unchanged
⚫ Mostly added new definitions

Agenda
I.     Intro and brief history: L. Hirsch   1:30-1:40 pm (10 min)

II.    Background EEG, suppression-burst, reactivity, state changes,
       and CAPE: M.W.K. Fong          1:40 - 2:10 (23 min + 7 min Q&A)

III.   Rhythmic and Periodic Patterns, including Extreme Delta Brush:
                  N. Gaspard             2:10 - 2:40 (23 min + 7 min Q&A)

IV.    Electrographic and Electroclinical seizures, BIRDs and the Ictal-
       Interictal Continuum: L. Hirsch     2:40 – 3:10 (23 min + 7 min Q&A)

V.     Cases/reading session: M. Leitinger 3:10 – 3:30 (20 min)