Electroencephalogram Bispectral Analysis Predicts the Depth of Midazolam-induced Sedation

Abstract

The EEG-BI appears to be a useful parameter for assessing midazolam-induced sedation and can predict the likelihood of a patient responding to verbal commands or to shaking of the head during midazolam-induced sedation.

Evaluation of two processed EEG analyzers for assessment of sedation after coronary artery bypass grafting

“…The positive predictive values were consequently low, while the negative predictive values were acceptable due to the post hoc fixed level of the line of discrimination. This variability is much greater than in studies with volunteers, which report a coefficient of variation of approximately 20 % for BIS and SEF 95 % [22]. This may be the result of the great interindividual variability in stress reception and processing in a busy ICU environment, which may not be suppressed by analgesia and sedation, producing the processed EEG variability in these patients.…”

“…Indeed, an investigation comparing SEF 95 % and BIS of analyzer A for monitoring of loss and return of consciousness using propofol in healthy patients found a very limited value of SEF 95 % due to the biphasic EEG pattern of propofol [23]. Similarly, whereas BIS increased with recovery from the sedative effects in healthy patients, no consistent changes were found with the SEF 95 % [22]. Variants in software, fast Fournier transformation and artifact discrimination may explain the absence of distinction with SEF 95 % of monitor A in contrast to BIS of monitor A and SEF 90 % of monitor D.…”

Use of continuous bispectral EEG monitoring to assess depth of sedation in ICU patients

“…Compared with classical power-spectral analyses, which use the frequency and amplitude of the raw EEG signal to compute a processed univariate parameter [6], the BIS proprietary algorithm uses not only a complex Fourier transformation but also includes information about the influence of interrelations between different frequency components (phase coupling), beta-activation and isoelectricity. Liu et al [8] proved the usefulness of the BIS in the operating room to monitor depth of midazolam-induced sedation during surgery. Preliminary reports [9] on its use in ICU patients reveal a good correlation between the BIS and the Ramsay sedation score, which is still the gold standard' for assessing clinically the depth of sedation in ICU patients.…”

Bispectral Index Monitoring for Nurse-Administered Propofol Sedation During Upper Endoscopic Ultrasound: A Prospective, Randomized Controlled Trial

“…Bispectral index (BIS) monitoring (Aspect Medical Systems; Newton, MA) is an assessment of cortical activity that utilizes raw electroencephalography (EEG) waveforms to produce a dimensionless, quantitative measurement of a patient's level of consciousness [29,30]. BIS scores range from 0 (flat line EEG) to 100 (fully awake) with values of 60-70 and greater than 70 corresponding to deep sedation and moderate sedation, respectively [29][30][31].…”