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Quantitative topographical analysis of EEG during nonstandardized and standardized hyperventilation.

U Zwiener·S Löbel·M Rother·M Funke
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Abstract

The aim of this study was to compare the topographical quantitative EEG (qEEG) changes induced by nonstandardized hyperventilation and those induced by standardized hyperventilation (with the end-tidal PCO2 being maintained at 2 kPa [15 mm Hg]). We examined 18 healthy volunteers during nonstandardized and 20 during standardized hyperventilation. During nonstandardized hyperventilation, the mean spectral power density in this group significantly increased 1.9 fold within the delta-, 2.2 fold within the theta-, 1.8 fold within the alpha-, and 1.9 fold within the beta-frequency band. There was no significant change of the power ratio and was no topographic difference between 4 frequency bands investigated. During standardized hyperventilation, the mean spectral power density in the group significantly increased to 12.9 fold within the delta-, to 7.6 fold within the theta-, to 1.4 fold within the alpha-, and to 2.4 fold within the beta frequency band. The power ratio decreased significantly. Such a pronounced EEG slowing with delta and theta augmentation was never found during nonstandardized hyperventilation. We conclude that a consistent slowing of the qEEG in all leads including a constant topographical maximum can only be induced by standardized, sufficiently pronounced hyperventilation.

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AdultBrain MappingElectroencephalographyFemaleFrontal LobeHumansHyperventilationMaleOccipital LobeParietal LobeTemporal LobeTime FactorsComparative StudyJournal Article

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U Zwiener, S Löbel, M Rother, M Funke. 1998. Quantitative topographical analysis of EEG during nonstandardized and standardized hyperventilation.. https://doi.org/10.1097/00004691-199811000-00011

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