Can electrophysiological assessments of brain function be useful to the intensive care physician in daily clinical practice?

Pierre C Pandin

doi:10.1186/cc3011

Abstract

Changes in electroencephalogram parameters and auditory event-related potentials, induced by interruption to propofol sedation in intensive care patients, provide a number of electrophysiological measures that can be used to assess neurological function accurately. Studies of electroencephalogram parameters suggest that power spectral estimation, as root mean square power, is more useful and precise than spectral edge frequency 95% in evaluating the functional integrity of the brain. When such parameters are used to evaluate neurological function, in particular the N100 and mismatch negativity components, a precise assessment of a patient's readiness to awaken from a pharmacologically induced coma (such as sedation) can be obtained. In terms of ease of use, however, it is more difficult to establish whether N100 or mismatch negativity is superior.

Highlights

Can electrophysiological assessments of brain function be useful to the intensive care physician in their daily clinical practice? The study reported by Yppärilä and coworkers [1] sheds some light on this issue
Evaluation of electroencephalogram (EEG) parameters and event-related potential (ERP) components in order to assess neurological function is perfectly valid from a clinical perspective, the vast majority of intensive care physicians do not incorporate these electrophysiological measurement tools into their daily clinical practice, primarily because they are unaware that such techniques can be highly useful
Efforts directed at promoting widespread use of electrophysiological assessment techniques in the intensive care unit (ICU) will need to be supported on one hand by dual neurological and pharmacological evaluation methods, and on the other hand by ongoing clinical application of the EEG and ERP assessment methods, as described by Yppärilä and coworkers [1]

Summary

Introduction

Can electrophysiological assessments of brain function be useful to the intensive care physician in their daily clinical practice? The study reported by Yppärilä and coworkers [1] sheds some light on this issue. Evaluation of electroencephalogram (EEG) parameters and event-related potential (ERP) components in order to assess neurological function is perfectly valid from a clinical perspective, the vast majority of intensive care physicians do not incorporate these electrophysiological measurement tools into their daily clinical practice, primarily because they are unaware that such techniques can be highly useful. The report is of particular interest because the findings illustrate so well the complementary relationship that exists between EEG and ERP electrophysiological evaluation techniques They offer greater precision regarding the AEP = auditory evoked potential; EEG = electroencephalogram; ERP = event-related potential; ICU = intensive care unit; MMN = mismatch negativity; RMS = root mean square; SEF95 = spectral edge frequency 95%.

Conclusion

Guérit JM

Findings

John ER