Neuroprotective effect of volatile anesthetic agents: molecular mechanisms.
BACKGROUND
Intra-operative cerebral ischemia can be catastrophic, and volatile anesthetic agents have been recognized for their potential neuroprotective properties since the 1960s. In this review, we examine the neuroprotective effects of five volatile anesthetic agents in current or recent clinical use: isoflurane, sevoflurane, desflurane, halothane and enflurane.


METHODS
A review of publications in the National Library of Medicine and National Institutes of Health database from 1970 to 2007 was conducted.


RESULTS
Volatile anesthetic agents have been shown to be neuroprotective in multiple animal works of ischemic brain injury. Short-term neuroprotection (<1 week post-ischemia) in experimental cerebral ischemia has been reported in multiple works, although long-term neuroprotection (> or = 1 week post-ischemia) remains controversial. Comparison works have not demonstrated superiority of one specific volatile agent over another in experimental models of brain injury. Relatively few human works have examined the protective effects of volatile anesthetic agents and conclusive evidence of a neuroprotective effect has yet to emerge from human works.


CONCLUSIONS
Proposed mechanisms related to the neuroprotective effect of volatile anesthetic agents include activation of ATP-dependent potassium channels, up-regulation of nitric oxide synthase, reduction of excitotoxic stressors and cerebral metabolic rate, augmentation of peri-ischemic cerebral blood flow and up-regulation of antiapoptotic factors including MAP kinases.
Matchett
Gerald A
GA
Department of Anesthesiology, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA.
Allard
Martin W
MW
Martin
Robert D
RD
Zhang
John H
JH
D018685:Anesthetics, Inhalation / Q000008:administration & dosage*; D000818:Animals; D002545:Brain Ischemia / Q000378:metabolism / Q000503:physiopathology / Q000517:prevention & control*; D016208:Databases, Factual / Q000706:statistics & numerical data; D004195:Disease Models, Animal; D006801:Humans; D007473:Ion Channels / Q000187:drug effects; D018696:Neuroprotective Agents / Q000008:administration & dosage*; D012039:Regional Blood Flow / Q000187:drug effects
D018685:Anesthetics, Inhalation; D007473:Ion Channels; D018696:Neuroprotective Agents