Brain protection by anesthetic agents

PURPOSE OF REVIEW: Patients at risk for perioperative stroke, or those who have suffered recent cerebral injury, may benefit from neuroprotective properties of anesthetic agents during surgery. This manuscript reviews recent clinical and experimental evidence for neuroprotective effects of common anesthetic agents, and presents potential mechanisms involved in anesthetic neuroprotection. RECENT FINDINGS: Although strong experimental data support a neuroprotective potential of several anesthetic agents, specifically isoflurane and xenon, consistent long-term protection by either agent has not been demonstrated. Unfortunately, there is a lack of clinical studies that would support the use of any one anesthetic agent over the others. Mechanisms of neuroprotection by anesthetic agents appear to involve suppression of excitatory neurotransmission, and potentiation of inhibitory activity, which may contribute to the reduction of excitotoxic injury. Activation of intracellular signaling cascades that lead to altered expression of protective genes may also be involved. SUMMARY: Solid experimental evidence supports neuroprotection by anesthetic agents. It is too early to recommend any specific agent for clinical use as a neuroprotectant, however. Further study is warranted to unravel relevant mechanisms and to appreciate the potential clinical relevance of experimental findings.