Quantitative Analysis of EEG Records in Distinct States of Consciousness: A Case Study on Brazilian Patient

This article describes the case of a patient admitted to the Intensive Care Unit of the University Hospital, at Federal University of Uberlandia, Brazil, under diagnosis of cranial trauma. Three EEG records obtained at different levels of consciousness of this patient were analyzed and these were compared with a neurologically normal EEG. The aim was to assess whether the computational biomarkers (PCP and COHERENCE), estimated based on the EEG power spectral density, can distinguish normal state from pathological states of consciousness. Results point out that both biomarkers can be used to separate these two clinical situations. Particularly, alfa and delta rhythms play a very important role in this case, as well as electrodes tied to frontal and occipital regions. These findings agree with literature, which reports conclusions considering mainly patients from Europe and the USA, since no articles involving Brazilian patients were found by the authors. In addition, since all EEG are tied to the same organism, comparisons are much more reliable, since we avoid analysis of different clinical situations associated with different ethiologies as well as with different locations of neuroanatomical lesions.