Acoustic evoked brainstem potentials--patterns of stimulus artefacts in irreversible coma
Litscher, G.; Schwarz, G.; Pfurtscheller, G.; Kleinert, R.; List, W.F.
Eeg-Emg Zeitschrift für Elektroenzephalographie Elektromyographie und verwandte Gebiete 23(2): 82-87
1992
ISSN/ISBN: 0012-7590 PMID: 1505441 Document Number: 397450
Brainstem auditory evoked potentials (BAEP) were performed in a total of 20 subjects (mean age 33.2 +/- 15.1 years; severe head injury in most cases) with the diagnosis of coma dépassé. The control group consisted of 33 healthy volunteers (mean age 26.9 +/- 5.3 years). The presence, latency and amplitude of the single BAEP-components and the variations of the stimulus artifact were evaluated. The mean amplitudes of the stimulus artifact of the brain dead subjects were calculated (means +/- SD) to be 0.26 +/- 0.12 microV (control group: 0.11 +/- 0.03 microV). Pathological alterations of the mechanics of the inner ear as well as extracerebral changes in conductivity or stimulus related depolarization processes in extracerebral parts of the auditory system were taken into consideration to be possible reasons for this significant (p less than 0.001; t-test) difference.