Electroencephalographic features of discontinuous activity in anesthetized infants and children

Abstract

BackgroundDiscontinuous electroencephalographic activity in children is thought to reflect brain inactivation. Discontinuity has been observed in states of pathology, where it is predictive of adverse neurological outcome, as well as under general anesthesia. Though in preterm-infants discontinuity reflects normal brain development, less is known regarding its role in term children, particularly in the setting of general anesthesia. Here, we conduct a post-hoc exploratory analysis to investigate the spectral features of discontinuous activity in children under general anesthesia.MethodsWe previously recorded electroencephalography in children less than forty months of age under general anesthesia (n = 65). We characterized the relationship between age, anesthetic depth, and discontinuous activity, and used multitaper spectral methods to compare the power spectra of subjects with (n = 35) and without (n = 30) discontinuous activity. In the subjects with discontinuous activity, we examined the amplitude and power spectra associated with the discontinuities and analyzed how these variables varied with age.ResultsCumulative time of discontinuity was associated with increased anesthetic depth and younger age. In particular, age-matched children with discontinuity received higher doses of propofol during induction as compared with children without discontinuity. In the tens of seconds preceding the onset of discontinuous activity, there was a decrease in high-frequency power in children four months and older that could be visually observed with spectrograms. During discontinuous activity, there were distinctive patterns of amplitude, spectral edge, and power in canonical frequency bands that varied with age. Notably, there was a decline in spectral edge in the seconds immediately following each discontinuity.ConclusionDiscontinuous activity in children reflects a state of a younger or more deeply anesthetized brain, and characteristic features of discontinuous activity evolve with age and may reflect neurodevelopment.

Prefrontal Cortex Development in Health and Disease: Lessons from Rodents and Humans

“…This is accompanied by a global decrease in firing rate and broadband suppression of LFP power that leaves the ratio of fast:slow oscillations relatively unaffected [154]. Similar findings have also been reported from scalp EEG recordings in humans of roughly equivalent age (i.e., preterm or newborn babies) [154,155]. The lack of frequency-specific effects of anesthesia on the immature brain is in stark contrast to what occurs in the adult brain and is thought to underlie the particularly poor performance of EEG-based anesthesia-depth monitoring methods in newborn babies [156].…”

Longitudinal changes in aperiodic and periodic activity in electrophysiological recordings in the first seven months of life

“…More adaptive methods, such as the wavelet transform, can be used for optimizing resolution for each frequency band. These methods have been successful in assessing the EEG frequency content in anesthesia in infants ( Cornelissen et al, 2015 , Agrawal et al, 2019 ) or for investigating time-locked events, such as auditory evoked responses ( Kaminska et al, 2018 , Kushnerenko et al, 2002 ). Here, we opted for the cycle-based approach because we were primarily interested in the momentary dynamics of oscillations in a specific frequency band, without temporal integration over windows.…”

EEG monitoring during anesthesia in children aged 0 to 18 months: amplitude-integrated EEG and age effects

“…An age effect that can be observed in the pediatric EEG during anesthesia is an increase in the power of the EEG with increasing age. This effect was described for example in a study in children aged 0 to 17 months [ 9 ] and in another study comparing two groups of children aged 0–3 months and 4–6 months, respectively [ 10 ]. During the first few months of life, the frequency composition of the EEG during anesthesia changes.…”