Neurophysiologie clinique = Clinical neurophysiology
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Sleep recordings and evoked potentials (EPs) were used in five comatose children to evaluate their predictive value for outcome following a severe comatose state. ⋯ In the three anoxic comas we observed BER abnormalities and the absence of SEP N20 associated with wide cortical lesions with brainstem extension. Sleep recordings showed major alterations of the wake-sleep cycle without any improvement in M6. Abnormalities included loss of the normal REM-sleep pattern associated with alteration of NREM sleep and periods of increase in motor activity without EEG arousal. This sleep pattern appeared to be associated with involvement of the brainstem. In the two traumatic comas, alterations of the early cortical SEP responses were less severe and the BERs were normal. Some sleep spindles were observed as well as the persistence of sleep cycles in the first weeks post-coma. The combined use of EEG, EPs and polysomnography improved the outcome prediction in comparison with the use of just one modality. EPs and sleep recordings were far superior to clinical evaluation and to GCS in the appreciation of the functional status of comatose children. The reappearance of sleep patterns is considered to be of favorable prognosis for outcome of the coma state, as is the presence of sleep spindles in post-trauma coma. This study showed that EPs and sleep recordings help to further distinguish between patients with good or bad outcomes.