From the Guidelines
Burst suppression is a pattern on electroencephalogram (EEG) characterized by alternating periods of high-amplitude electrical activity (bursts) and periods of minimal or no activity (suppression), with more than 50% of the EEG record consisting of periods of EEG voltage <10 µV, as defined in the 2015 European Resuscitation Council and European Society of Intensive Care Medicine guidelines 1. This pattern indicates profound brain dysfunction and is typically seen in severe brain injuries, deep anesthesia, hypothermia, or drug-induced coma.
- The definition of burst suppression is crucial for prognostication, as most studies do not comply with the standard definition, which may lead to varying results.
- Burst suppression can be a transient finding in comatose survivors of cardiac arrest, and its prognostic significance depends on the timing and duration of the pattern.
- According to the 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science, burst suppression within 24 hours after return of spontaneous circulation (ROSC) predicted poor neurological outcome with 50% to 100% specificity and 50% to 51.5% sensitivity 1.
- The use of burst suppression as a prognostic tool is still evolving, and more research is needed to fully understand its implications.
- In clinical practice, burst suppression is often intentionally induced for therapeutic purposes, such as in refractory status epilepticus or severe traumatic brain injury, using medications like propofol, midazolam, or pentobarbital, with the goal of achieving a suppression ratio of 50-90% and reducing cerebral oxygen consumption and intracranial pressure.
- Continuous EEG monitoring is essential during burst suppression therapy to ensure the target level is maintained, and close monitoring of hemodynamics is necessary due to the potential for hypotension and respiratory depression.
From the FDA Drug Label
With increasing patient age, pharmacokinetic changes are such that, for a given IV bolus dose, higher peak plasma concentrations occur, which can explain the decreased dose requirement. These higher peak plasma concentrations in the elderly can predispose patients to cardiorespiratory effects including hypotension, apnea, airway obstruction, and/or arterial oxygen desaturation ... as measured by EEG burst suppression
Burst suppression is a pattern on an electroencephalogram (EEG) that is used to measure the effect of certain medications, such as propofol, on brain activity. It is characterized by periods of high-voltage electrical activity in the brain, followed by periods of little or no activity. In the context of propofol, burst suppression is used to assess the depth of anesthesia or sedation. 2
From the Research
Definition of Burst Suppression
- Burst suppression is an electroencephalogram (EEG) pattern characterized by a quasi-periodic alternation between high-voltage 'bursts' and isoelectric 'suppressions' lasting seconds or minutes 3, 4, 5.
- It is a marker of profound brain inactivation and unconsciousness, occurring in conditions such as hypothermia, deep general anesthesia, infant encephalopathy, and coma 3, 5.
Characteristics of Burst Suppression
- Burst suppression can be asynchronous across the cortex, with different regions exhibiting different patterns of activity 3.
- The state of burst suppression can occur in a limited cortical region, while other areas exhibit ongoing continuous activity 3.
- Bursts can have a complex temporal structure, recapitulating the spectral dynamics of the state preceding burst suppression 3.
Clinical Applications of Burst Suppression
- Burst suppression is used as an electrophysiological endpoint in pharmacologically induced coma for brain protection after traumatic injury and during status epilepticus 3, 4.
- It can be used to monitor the level of brain inactivation and to guide treatment in patients with refractory status epilepticus or refractory intracranial hypertension 6.
- Different anesthetics, such as propofol and sevoflurane, can induce distinct burst suppression patterns 7.
Quantification and Control of Burst Suppression
- The burst suppression level can be quantified using the burst suppression probability (BSP), which represents the brain's instantaneous probability of being in the suppressed state 4.
- A brain-machine interface (BMI) can be used to automatically control the level of burst suppression in real-time, using EEG observations and a stochastic controller 4.