Is Electroencephalographic Burst-Suppression Good, Bad, or Indifferent for Brain Health? Context Matters

Intraoperative burst-suppression (BSP) has long been postulated to be associated with an increased risk of postoperative delirium (POD) based on data from human experimental studies and meta-analyses. However, the effects of BSP on POD are not consistently demonstrated in large-scale randomized controlled trials. At a minimum, this warrants an explanation of the discrepancies between these results, and at a maximum, prompts the questioning of the utility of intraoperative electroencephalographic (EEG) monitoring for POD altogether. Here, we provide a narrative review of the mechanisms of BSP generation in several clinical contexts, including those produced by general anesthetics and neuronal pathologies, the role and utility of BSP in cerebral protection strategies, and the significance of BSP with respect to long-term functional neurological outcomes. We offer a framework with which to understand BSP generation across clinical contexts and discuss its scientific and clinical implications.