Density Spectral Array (DSA) where brain waves are represented in colour with a 2-dimensional view. This creates a graphical representation of the patient’s pEEG frequencies. Red show the dominant frequencies with cooler blues showing the less dominant frequencies. It also gives you visualisation of the anaesthetics used and which bands of pEEG are affected based on the individual drugs given.
Spectral Edge Frequency (SEF) The SEF is a white line displayed on the DSA where 95% of the total power lies on one side of the line and 5% lies on the other. The number is also shown in white at the top left of the graph. SEF is another tool that can help to confirm if changes in the BIS™ number are due to EMG stimuli by showing shifts in power.
Suppression Ratio is available as a secondary parameter and displays the percent of time (over the last 63 seconds) that the EEG was flat or isoelectric. This, combined with Suppression Time, enables you to avoid deep anaesthesia which has been shown in studies to relate to post-operative complications.
Suppression Time is a new secondary parameter unique to BIS™ that the displays the cumulative time spent in EEG-suppressed state. Evidence has shown when cardiac patients spend more time in burst suppression they are at more risk for post-operative delirium.
* compared BIS™ SW version 3.25 and lower
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