Anesthesiology
February 6, 2020
Andria Pelentritou, Levin Kuhlmann, John Cormack et al.
15 citations
Xenon and nitrous oxide produce different patterns of brain oscillatory power changes, depending on the gas and the recording method. Xenon increased low-frequency delta and theta power only at loss of responsiveness (delta: 208.3%, theta: 107.4% in MEG; delta: 260.3%, theta: 116.3% in EEG). Nitrous oxide increased high-frequency gamma power (low gamma: 46.3%, high gamma: 45.7% in MEG) and reduced frontal alpha power at 0.75 MACawake in MEG (44.4% reduction) and at 0.50 MACawake in EEG (44.0% reduction). The findings show no clear universal features of action for these two gaseous anesthetics, and differences between MEG and EEG must be considered for accurate brain state monitoring during anesthesia.
bioRxiv (Cold Spring Harbor Laboratory)
March 9, 2019
Andria Pelentritou, Levin Kuhlmann, John Cormack et al.
1 citation
preprint
Equivalent stepwise subanesthetic doses of the NMDA-antagonists nitrous oxide (N2O) and xenon (Xe) produce distinct, frequency-dependent changes in cortical oscillatory source power, measured with simultaneous magnetoencephalography (MEG) and electroencephalography (EEG). At the highest Xe concentration (42%, 1.30 MAC-awake), delta and theta band power significantly increased in both MEG and EEG. N2O administration reduced frontal alpha power more strongly than equivalent Xe doses. N2O alone increased MEG (but not EEG) high-frequency gamma power, with occipital low gamma and widespread high gamma rises. These results demonstrate divergent MEG and EEG signatures of dissociative anesthesia.
Journal of visualized experiments : JoVE
January 13, 2018
Andria Pelentritou, Levin Kuhlmann, John Cormack et al.
Inhaling the gaseous anesthetics nitrous oxide (N2O) and xenon (Xe) allows study of brain activity during unconsciousness via simultaneous magnetoencephalography (MEG) and electroencephalography (EEG). Healthy male participants received step-wise increasing concentrations of Xe (8, 16, 24, 42%) and N2O (16, 32, 47%) in a repeated measures cross-over design. An auditory continuous performance task tracked responsiveness. The protocol, refined over multiple sessions, details subject recruitment, equipment setup, data collection, and basic analysis. Results show sensor-level raw data, spectral topography, minimal head movements, and level-dependent effects on auditory evoked responses. The method can be adapted for volatile and intravenous anesthetics to advance understanding of macro-scale anesthesia mechanisms.