Comparison of EEG during normal sleep and anesthesia with two clinical monitors for the purpose of studying anesthetic depth

Abstract

Investigators have shown that monitoring the electrical activity of the brain can indicate CNS status and that it can enhance the assessment of anesthetic depth when used with other clinical signs. It is important to understand the variables that are produced by EEG monitors and used to assess CNS status and to understand similarities and differences between stages of intra-operative sleep. This investigation used well studied stages of normal sleep for comparison with different stages of intra-operativesleep. EEG data from 6 intra-operative from 6 intra-operative and 6 normal sleep subjects were collected on FM recorder and processed with 2 clinical EEG monitors. The results failed to show any similarities in EEG variables between stages of normal sleep and intra-operative sleep. Comparison of the two monitors in assessing similar EEG waveforms showed that they have different sensitivities to frequency and amplitude and they produce different results with differences in their ability to separate information.