Continuous EEG monitoring in severe Guillain-Barré syndrome patients.

When patients Guillain-Barré syndrome have complete paralysis clinical measures of sedation cannot be applied. In this situation continuous EEG offers a convenient, effective method of monitoring the depth of sedation, using spectral edge frequency (SEF) to quantify EEG activity. The authors report 3 patients with severe Guillain-Barré syndrome managed with sedation aimed at a SEF95 below 4.0 Hz (delta coma), using a subhairline montage with the DATEX bedside EEG module. Two of the patients were easily managed using this system for an average of 16 days, and both were completely amnestic of this period of time with no serious complication. The third one had still some residual muscle activity and SEF was unreliable in this case, so its use was abandoned. Continuous EEG monitoring using SEF is a useful tool to manage sedation in the most severely paralyzed Guillain-Barré syndrome patients. Incorporation of a low-pass filter would be of benefit to remove any residual muscle activity, which confounds the target level of sedation with this method; SEF has theoretical advantages over the bispectral index in this population. Comparative studies of various continuous EEG monitoring methods in such patients should better define their relative effectiveness.