Clinical Electroencephalography for Anesthesiologists: Part I: Background and Basic Signatures
Patrick L Purdon1, Aaron Sampson, Kara J Pavone
1From the Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, and Department of Anesthesia, Harvard Medical School, Boston, Massachusetts (P.L.P.); Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts (A.S., K.J.P.); and Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts; Department of Anesthesia, Harvard Medical School, Boston, Massachusetts; Institute for Medical Engineering and Science and Harvard-Massachusetts Institute of Technology, Health Sciences and Technology Program; and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts (E.N.B.).
Electroencephalogram (EEG) indices for anesthesia depth monitoring are limited. Different anesthetics create unique brain states visible in EEG, necessitating a neurophysiological approach for accurate patient monitoring.
Area of Science:
- Anesthesiology
- Neuroscience
- Biophysics
Background:
- Current electroencephalogram (EEG)-based depth-of-anesthesia monitoring indices assume anesthetic-invariant brain states.
- This assumption is challenged by the distinct molecular targets and neural circuits affected by different anesthetic agents.
- These differences result in unique, observable brain states in the EEG.
Purpose of the Study:
- To educate anesthesiologists on interpreting unprocessed EEG and spectrograms.
- To detail the EEG signatures of common intravenous and inhaled anesthetics.
- To propose a neurophysiologically informed paradigm for anesthesia monitoring.
Main Methods:
- Review of the biophysics of the electroencephalogram (EEG).
- Analysis of EEG signatures associated with propofol, dexmedetomidine, ketamine, sevoflurane, isoflurane, desflurane, and nitrous oxide.
- Discussion of anesthetic-induced brain states.
Main Results:
- Different anesthetics produce distinct EEG patterns reflecting unique brain states.
- The unprocessed EEG and its spectrogram can visualize these anesthetic-specific brain states.
- This forms the basis for a more precise monitoring approach.
Conclusions:
- Anesthetic agents induce unique brain states with characteristic EEG signatures.
- Monitoring these signatures offers a more accurate method for assessing depth of anesthesia.
- This approach shifts towards a neurophysiologically based brain state monitoring paradigm.
More Related Videos
10:23Equipment Setup and Artifact Removal for Simultaneous Electroencephalogram and Functional Magnetic Resonance Imaging for Clinical Review in Epilepsy
Published on: June 23, 2023
13:32Recording Human Electrocorticographic ECoG Signals for Neuroscientific Research and Real-time Functional Cortical Mapping
Published on: June 26, 2012