Burst-suppression ratio underestimates absolute duration of electroencephalogram suppression compared with visual analysis of intraoperative electroencephalogram

Abstract

Our findings suggest that SedLine ® (machine)-generated indices might underestimate the minutes of EEG suppression, thereby reducing the sensitivity for detecting patients at risk for POD. Thus, the monitoring of machine-generated BSR and PSI™ might benefit from the addition of a visual tracing of the EEG to achieve a more accurate and real-time guidance of anaesthesia depth monitoring and the ultimate goal, to reduce the risk of POD.

Intraoperative electroencephalogram suppression at lower volatile anaesthetic concentrations predicts postoperative delirium occurring in the intensive care unit

“…This methodology has recently been shown to underestimate the duration of suppression compared to visual analysis of the electroencephalogram. 25 However, this limitation would impact all the patients uniformly and should not change the outcomes of the study. This was a single-centre study, so the results may not be generalizable to other settings.…”

Overlapping cognitive disintegration of anaesthesia and delirium

“…Another recent paper in the British Journal of Anaesthesia demonstrated inadequacies in the SedLine ® monitor, Masimo, Irvine, California, USA for detecting burst suppression. 6 A visual analysis of intraoperative EEG suppression was superior to the SedLine ® monitor, and the number of minutes of visually identified (but not SedLine ® identified) burst suppression significantly correlated with postoperative delirium. In the future, novel monitors might be able to facilitate detection of patients with intraoperative burst suppression.…”

“…Recent data suggest that smoking is not associated with microglial priming, 26 making connectivity changes a more plausible mechanism linking to delirium. Based on prior studies showing that frontal EEG-guided anaesthesia reduces delirium, the work of Fritz and colleagues 5 supports the idea that it is wise to avoid burst suppression under anaesthesia, 6 and to be vigilant that patients who most easily enter the burst-suppression EEG pattern might be most at risk of postoperative delirium.…”

“…This finding is highly relevant towards the discussion surrounding depth of anaesthesia monitoring and prior work on the association of burst suppression and delirium. 6,7 In 2017, the European Society of Anaesthesiology published guidelines recommending the monitoring of anaesthesia depth to prevent postoperative delirium. 8 This recommendation was based on evidence that demonstrated a significant reduction in postoperative delirium with the use of bispectral index (BIS)-guided anaesthesia.…”

Monitoring the brain strikes a discordant note for anesthesiologists

“…9,10 Current indices could be deficient in their ability to reflect deep anesthesia accurately. (i) They might be imprecise in their detection of EEG suppression, 11 and (ii) they often show values only suggestive of deep anesthesia when the percentage time of EEG suppression passes a particular arbitrary threshold. 12 Unfortunately, the currently available processed EEG monitors are demonstrably discordant in a variety of circumstances, which has likely curtailed their adoption among discerning anesthesiologists.…”