Misinterpretation and Limitations of pEEG Monitoring During Multimodal General Anesthesia: A Case Report

The adequate titration of hypnotic agents can be achieved using processed electroencephalogram (pEEG) monitors. pEEG monitors with a spectrogram, such as bilateral bispectral index (BIS), are useful because they can show different signatures that suggest the effect of a given drug on brain activity. Multimodal general anesthesia is based on a combination of hypnotic and antinociceptive agents. We report a case of awareness in a patient monitored with bilateral BIS during multimodal general anesthesia. This case illustrates the limitations of the index and the value of the spectrogram in the assessment of hypnosis.