Understanding the Effects of General Anesthetics on Cortical Network Activity Using Ex Vivo Preparations

Anesthesiology. 2019 Jun;130(6):1049-1063. doi: 10.1097/ALN.0000000000002554.

Abstract

General anesthetics have been used to ablate consciousness during surgery for more than 150 yr. Despite significant advances in our understanding of their molecular-level pharmacologic effects, comparatively little is known about how anesthetics alter brain dynamics to cause unconsciousness. Consequently, while anesthesia practice is now routine and safe, there are many vagaries that remain unexplained. In this paper, the authors review the evidence that cortical network activity is particularly sensitive to general anesthetics, and suggest that disruption to communication in, and/or among, cortical brain regions is a common mechanism of anesthesia that ultimately produces loss of consciousness. The authors review data from acute brain slices and organotypic cultures showing that anesthetics with differing molecular mechanisms of action share in common the ability to impair neurophysiologic communication. While many questions remain, together, ex vivo and in vivo investigations suggest that a unified understanding of both clinical anesthesia and the neural basis of consciousness is attainable.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Review

MeSH terms

  • Anesthetics, General / administration & dosage*
  • Animals
  • Cerebral Cortex / drug effects*
  • Cerebral Cortex / physiology
  • Electroencephalography / drug effects*
  • Electroencephalography / methods
  • Humans
  • Nerve Net / drug effects*
  • Nerve Net / physiology
  • Organ Culture Techniques

Substances

  • Anesthetics, General