Bioelectric activity monitoring of the hippocampal complex: action of inhalation anesthetics as a functional sample

Monitoring of the bioelectric activity of the hippocampal complex is performed according to the indications of patients with pharmacoresistant mesial temporal lobe epilepsy, who are indicated for surgical removal of the epileptic focus. The work was aimed at comparing the dynamics of the amplitude-frequency parameters of the bioelectrical activity of the hippocampal complex under the action of general anesthetics by comparing the parameters recorded before surgery and intraoperatively. The study included 8 patients with mesial temporal lobe epilepsy who, within the framework of pre-surgical planning, underwent invasive monitoring of the bioelectrical activity of the cortex and hippocampal com- plex, and then underwent surgical resection of the epileptic focus under general anesthesia with sevoflurane. Registration of 12 hippocampal tracks was carried out in dynamics: during extraoperative and intraoperative neurophysiological monitoring. In the state of calm wakefulness, the pattern of bioelectric activity of the hippocampal complex without structural changes was formed mainly by the activity of the alpha and theta frequency ranges. Under general anesthesia with sevoflurane, a slow-wave delta-range activity was recorded on the intraoperative ES- ubCoG. When the hippocampal complex was involved in the epileptic system, its activity in the state of passive wakefulness was represented by the slow-wave frequency range. Under the conditions of inhalation anesthesia with sevoflurane, the proportion of delta activity significantly decreased, and a state of dysrhythmia was observed without a clear dominance of activity in any range.

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