Electroencephalogram (EEG) approaches may provide important information about developmental changes in brain-state dynamics during general anesthesia. We used multi-electrode EEG, analyzed with multitaper-spectral methods and video recording of body movement to characterize the spatiotemporal dynamics of brain activity in 36 infants 0-6 months old when awake, and during maintenance-of and emergence-from sevoflurane general anesthesia. During maintenance: 1)slow-delta oscillations were present in all ages; 2)theta and alpha oscillations emerged around 4months; 3)unlike adults, all infants lacked frontal alpha predominance and coherence. Alpha power was greatest during maintenance, compared to awake and emergence in infants at 4-6months. During emergence, theta and alpha power decreased with decreasing sevoflurane concentration in infants at 4-6months. These EEG dynamic differences are likely due to developmental factors including regional differences in synaptogenesis, glucose metabolism, and myelination across the cortex. We demonstrate the need to apply age-adjusted analytic approaches to develop neurophysiologic-based strategies for pediatric anesthetic state monitoring.
Human subjects: Boston Children's Hospital Institutional Review Board (IRB) approved the study (IRB Protocol Number: IRB-P00003544), and informed written consent was obtained from parents/legal guardians before each study. The study conformed to the standards set by the Declaration of Helsinki and Good Clinical Practice guidelines.
- Jody C Culham, University of Western Ontario, Canada
© 2015, Cornelissen et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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