Anesthetic action on the transmission delay between cortex and thalamus explains the beta-buzz observed under propofol anesthesia.

In recent years, more and more surgeries under general anesthesia have been performed with the assistance of electroencephalogram (EEG) monitors. An increase in anesthetic concentration leads to characteristic changes in the power spectra of the EEG. Although tracking the anesthetic-induced changes...

Full description

Saved in:
Bibliographic Details
Main Authors: Meysam Hashemi, Axel Hutt, Darren Hight, Jamie Sleigh
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2017-01-01
Series:PLoS ONE
Online Access:https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0179286&type=printable
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849715564012896256
author Meysam Hashemi
Axel Hutt
Darren Hight
Jamie Sleigh
author_facet Meysam Hashemi
Axel Hutt
Darren Hight
Jamie Sleigh
author_sort Meysam Hashemi
collection DOAJ
description In recent years, more and more surgeries under general anesthesia have been performed with the assistance of electroencephalogram (EEG) monitors. An increase in anesthetic concentration leads to characteristic changes in the power spectra of the EEG. Although tracking the anesthetic-induced changes in EEG rhythms can be employed to estimate the depth of anesthesia, their precise underlying mechanisms are still unknown. A prominent feature in the EEG of some patients is the emergence of a strong power peak in the β-frequency band, which moves to the α-frequency band while increasing the anesthetic concentration. This feature is called the beta-buzz. In the present study, we use a thalamo-cortical neural population feedback model to reproduce observed characteristic features in frontal EEG power obtained experimentally during propofol general anesthesia, such as this beta-buzz. First, we find that the spectral power peak in the α- and δ-frequency ranges depend on the decay rate constant of excitatory and inhibitory synapses, but the anesthetic action on synapses does not explain the beta-buzz. Moreover, considering the action of propofol on the transmission delay between cortex and thalamus, the model reveals that the beta-buzz may result from a prolongation of the transmission delay by increasing propofol concentration. A corresponding relationship between transmission delay and anesthetic blood concentration is derived. Finally, an analytical stability study demonstrates that increasing propofol concentration moves the systems resting state towards its stability threshold.
format Article
id doaj-art-4c998032fc8d49649aad169bbd585a0d
institution DOAJ
issn 1932-6203
language English
publishDate 2017-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj-art-4c998032fc8d49649aad169bbd585a0d2025-08-20T03:13:19ZengPublic Library of Science (PLoS)PLoS ONE1932-62032017-01-01126e017928610.1371/journal.pone.0179286Anesthetic action on the transmission delay between cortex and thalamus explains the beta-buzz observed under propofol anesthesia.Meysam HashemiAxel HuttDarren HightJamie SleighIn recent years, more and more surgeries under general anesthesia have been performed with the assistance of electroencephalogram (EEG) monitors. An increase in anesthetic concentration leads to characteristic changes in the power spectra of the EEG. Although tracking the anesthetic-induced changes in EEG rhythms can be employed to estimate the depth of anesthesia, their precise underlying mechanisms are still unknown. A prominent feature in the EEG of some patients is the emergence of a strong power peak in the β-frequency band, which moves to the α-frequency band while increasing the anesthetic concentration. This feature is called the beta-buzz. In the present study, we use a thalamo-cortical neural population feedback model to reproduce observed characteristic features in frontal EEG power obtained experimentally during propofol general anesthesia, such as this beta-buzz. First, we find that the spectral power peak in the α- and δ-frequency ranges depend on the decay rate constant of excitatory and inhibitory synapses, but the anesthetic action on synapses does not explain the beta-buzz. Moreover, considering the action of propofol on the transmission delay between cortex and thalamus, the model reveals that the beta-buzz may result from a prolongation of the transmission delay by increasing propofol concentration. A corresponding relationship between transmission delay and anesthetic blood concentration is derived. Finally, an analytical stability study demonstrates that increasing propofol concentration moves the systems resting state towards its stability threshold.https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0179286&type=printable
spellingShingle Meysam Hashemi
Axel Hutt
Darren Hight
Jamie Sleigh
Anesthetic action on the transmission delay between cortex and thalamus explains the beta-buzz observed under propofol anesthesia.
PLoS ONE
title Anesthetic action on the transmission delay between cortex and thalamus explains the beta-buzz observed under propofol anesthesia.
title_full Anesthetic action on the transmission delay between cortex and thalamus explains the beta-buzz observed under propofol anesthesia.
title_fullStr Anesthetic action on the transmission delay between cortex and thalamus explains the beta-buzz observed under propofol anesthesia.
title_full_unstemmed Anesthetic action on the transmission delay between cortex and thalamus explains the beta-buzz observed under propofol anesthesia.
title_short Anesthetic action on the transmission delay between cortex and thalamus explains the beta-buzz observed under propofol anesthesia.
title_sort anesthetic action on the transmission delay between cortex and thalamus explains the beta buzz observed under propofol anesthesia
url https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0179286&type=printable
work_keys_str_mv AT meysamhashemi anestheticactiononthetransmissiondelaybetweencortexandthalamusexplainsthebetabuzzobservedunderpropofolanesthesia
AT axelhutt anestheticactiononthetransmissiondelaybetweencortexandthalamusexplainsthebetabuzzobservedunderpropofolanesthesia
AT darrenhight anestheticactiononthetransmissiondelaybetweencortexandthalamusexplainsthebetabuzzobservedunderpropofolanesthesia
AT jamiesleigh anestheticactiononthetransmissiondelaybetweencortexandthalamusexplainsthebetabuzzobservedunderpropofolanesthesia