Etiology of Burst Suppression EEG Patterns

Abstract

Burst-suppression electroencephalography (EEG) patterns of electrical activity, characterized by intermittent high-power broad-spectrum oscillations alternating with isoelectricity, have long been observed in the human brain during general anesthesia, hypothermia, coma and early infantile encephalopathy. Recently, commonalities between conditions associated with burst-suppression patterns have led to new insights into the origin of burst-suppression EEG patterns, their effects on the brain, and their use as a therapeutic tool for protection against deleterious neural states. These insights have been further supported by advances in mechanistic modeling of burst suppression. In this Perspective, we review the origins of burst-suppression patterns and use recent insights to weigh evidence in the controversy regarding the extent to which burst-suppression patterns observed during profound anesthetic-induced brain inactivation are associated with adverse clinical outcomes. Whether the clinical intent is to avoid or maintain the brain in a state producing burst-suppression patterns, monitoring and controlling neural activity presents a technical challenge. We discuss recent advances that enable monitoring and control of burst suppression.

Burst Suppression During General Anesthesia and Postoperative Outcomes: Mini Review

“…Standardizing burst suppression measurement is crucial to decreasing variability, as one study found that different interelectrode distances produce different burst durations (Moldovan et al, 2016). Measurement is also challenging since burst suppression patterns are inherently irregular-observed "spectral drifts" in bursts suggest that burst suppression may be more variable rather than a strict on-off switch of the EEG signature (Ching et al, 2012;Lewis et al, 2013;Liley and Walsh, 2013;Shanker et al, 2021).…”

“…Under these conditions, there are low levels of ATP, which may lead to protection of membrane integrity and cellular preservation (Forgacs et al, 2020). An important aspect of this hypothesis is that it can be applied to scenarios of decreased metabolic activity such as general anesthesia, hypothermia, and brain injury (Rampil, 1998;Ching et al, 2012;Shanker et al, 2021).…”

“…Burst suppression was first discovered by Derbyshire et al (1936) and consists of alternating episodes of isoelectric flat EEG periods with bursts of slow waves, including systemic and quasiperiodic variation where high voltage and isoelectric periods have variations between and within bursts (Figure 1) (Swank and Watson, 1949;Niedermeyer et al, 1999;Ching et al, 2012;Amzica, 2015;Purdon et al, 2015b). Burst suppression has been identified in hypothermia, coma, early infantile epileptic encephalopathy, and in general anesthesia-the focus of this review (Shanker et al, 2021). There are many controversies about burst suppression, including its relation to postoperative delirium (POD)-the postoperative onset of acute change from baseline attention, fluctuating awareness, and disturbances in cognition representative of acute brain failure (American Geriatrics Society Expert Panel on Postoperative Delirium in Older Adults, 2015).…”

Intraoperative BIS Monitoring Can Predict the Occurrence of EEG Suppression and Improve the Operation Quality

“…Figure 1 shows normal EEG signal and BS signal within 10 seconds under general anesthesia, which were intercepted by the EEG signal analysis software eeglab. BS does not occur during physiological sleep, excessive anesthesia and age are the main factors leading to BS [11,12] . The occurrence of BS decreases the metabolic rate of the brain.…”

A critical role for spike synchrony in determining steep 1/f slopes in the setting of bursting EEG patterns

“…Gao et al [2017] found propofol induced extremely steep 1/f slopes, and Colombo et al [2019] correlated steeper 1/f slopes with increasing degrees of unresponsiveness/unconsciousness from anesthesia. General anesthesia has been shown to cause cortex-wide synchronized bursting selectively in the layer V pyramidal cells [Bharioke et al, 2022] resulting in a state clinically referred to as burst-suppression [Steriade et al, 1994, Shanker et al, 2021. While bursting is grossly synchronized, there has been local variability in burst-onset time noted [Lewis et al, 2013].…”