ABSTRACT
Scalp electroencephalograms (EEGs) of brain dead patients are macroscopically flat under 7 or 10 microV/mm electroencephalograph sensitivity, but significant noises are detected in EEGs under 2 microV/mm sensitivity, interfering with the analysis. EEGs of 20 brain dead patients (17-76 years old) were therefore analyzed quantitatively as equivalent electric potentials in frequency bands delta, theta, alpha and beta using the automatic EEG analysis system developed in Kansai Medical University. The equivalent electric potentials in each band were about or less than 1 microV, which is used as a criterion of judgment of flat-line EEGs or brain death. Then, macroscopically flat EEGs of 12 comatose patients including infants (3-67 years old) were analyzed by the system, confirming their brain death. Thus, the automatic EEG analysis system could be used as a supporting tool to confirm flat-line EEGs of brain dead patients. ATAMAP II for Windows software was also evaluated.