EEG changes during fever produced by inductothermy (fever cabinet) in patients with neurosyphilis

Abstract

1. 1. Twenty-two cases, of which 21 were neurosyphilitic and one gonorrheal, were studied electroencephalographically during fever treatment induced by inductothermy. 2. 2. The common EEG changes during fever were: (1) increase of amplitude; (2) disorganization of EEG pattern; (3) slowing of frequencies. 3. 3. These changes were most marked from the frontal cortex, less marked from the motor cortex, least marked from the occipital cortex. 4. 4. Above mentioned EEG changes fluctuated with the rise and fall of body temperature. Most but not all of EEGs returned to the pre-febrile pattern with the return of temperature. This indicated that fever had some residual effect on the brain activity. 5. 5. In 5 cases fast waves appeared in the period of declining temperature. The fast activity occurred as bursts of fast waves or scattered spikes mixed with slow waves. 6. 6. Correlation was noted between the pre-febrile EEG patterns and changes with fever. (a) Pre-febrile slow wave patterns showed the most rapid and marked slowing during temperature. (b) Poorly organized patterns were most stable during temperature change. (c) Alpha wave patterns and low voltage fast wave patterns showed moderate changes during fever. (d) Fast wave patterns were apt to show fast waves during decline of temperature. 7. 7. There was no relation noted between the EEG changes and age, sex, clinical diagnosis, and degree of clinical improvement with fever treatment. 8. 8. Seven cases were reported mentally confused during the height of fever; their EEGs showed greater disorganization in the early stages of treatment than those patients not reported as confused. 9. 9. Beside individual susceptibility to change, the rise of metabolic rate, chronic hyperventilation, clouding of consciousness and relative cerebral hypoglycemia should be considered as possible mechanisms contributing to the changes of the EEG during the fever.