- Dose-dependent effects of isoflurane on TrkB and GSK3β signaling: Importance of burst suppression pattern. [Journal Article]
- NLNeurosci Lett 2019 02 16; 694:29-33
- CONCLUSIONS: Isoflurane dose-dependently regulates TrkB and GSK3β signaling and dosing associated with therapeutic outcomes in depressed patients produces most prominent effects.
- Terminal spreading depolarization and electrical silence in death of human cerebral cortex. [Case Reports]
- ANAnn Neurol 2018; 83(2):295-310
- Restoring the circulation is the primary goal in emergency treatment of cerebral ischemia. However, better understanding of how the brain responds to energy depletion could help predict the time avai…
Restoring the circulation is the primary goal in emergency treatment of cerebral ischemia. However, better understanding of how the brain responds to energy depletion could help predict the time available for resuscitation until irreversible damage and advance development of interventions that prolong this span. Experimentally, injury to central neurons begins only with anoxic depolarization. This potentially reversible, spreading wave typically starts 2 to 5 minutes after the onset of severe ischemia, marking the onset of a toxic intraneuronal change that eventually results in irreversible injury.
- Neural Correlates of Consciousness at Near-Electrocerebral Silence in an Asphyxial Cardiac Arrest Model. [Journal Article]
- BCBrain Connect 2017; 7(3):172-181
- Recent electrophysiological studies have suggested surges in electrical correlates of consciousness (i.e., elevated gamma power and connectivity) after cardiac arrest (CA). This study examines electr…
Recent electrophysiological studies have suggested surges in electrical correlates of consciousness (i.e., elevated gamma power and connectivity) after cardiac arrest (CA). This study examines electrocorticogram (ECoG) activity and coherence of the dying brain during asphyxial CA. Male Wistar rats (n = 16) were induced with isoflurane anesthesia, which was washed out before asphyxial CA. Mean phase coherence and ECoG power were compared during different stages of the asphyxial period to assess potential neural correlates of consciousness. After asphyxia, the ECoG progressed through four distinct stages (asphyxial stages 1-4 [AS1-4]), including a transient period of near-electrocerebral silence lasting several seconds (AS3). Electrocerebral silence (AS4) occurred within 1 min of the start of asphyxia, and pulseless electrical activity followed the start of AS4 by 1-2 min. AS3 was linked to a significant increase in frontal coherence between the left and right motor cortices (p < 0.05), with no corresponding increase in ECoG power. AS3 was also associated with a significant posterior shift of ECoG power, favoring the visual cortices (p < 0.05). Although the ECoG during AS3 appears visually flat or silent when viewed with standard clinical settings, our study suggests that this period of transient near-electrocerebral silence contains distinctive neural activity. Specifically, the burst in frontal coherence and posterior shift of ECoG power that we find during this period immediately preceding CA may be a neural correlate of conscious processing.
- Spinal Decerebrate-Like Posturing After Brain Death: A Case Report and Review of the Literature. [Case Reports]
- JIJ Intensive Care Med 2016; 31(9):622-4
- CONCLUSIONS: Extension-pronation movements that mimic decerebrate posturing may be seen in a delayed fashion after BD. Verification of lack of any brain activity (by both examination and multiple ancillary tests) in this case and others prompts us to attribute these movements as spinal cord reflexes and propose they be recognized within the rubric of accepted post-BD automatisms that should not delay diagnosis or necessitate confirmatory testing.
- Brain activity monitoring by compressed spectral array during deep hypothermic circulatory arrest in acute aortic dissection surgery. [Journal Article]
- KTKardiochir Torakochirurgia Pol 2014; 11(4):409-13
- CONCLUSIONS: The compressed spectral array method is clinically useful in monitoring brain bioactivity during emergency operations of acute aortic dissections. Electrocerebral silence occurs in 75% of patients during DHCA. The cognitive function of patients deteriorates significantly after operations with DHCA.
- EEG guidelines in the diagnosis of brain death. [Practice Guideline]
- NCNeurophysiol Clin 2015; 45(1):97-104
- In France, for the determination and diagnostic validation of brain death the law requires either two EEG recordings separated by a 4-hour observation period, both showing electrocerebral inactivity;…
In France, for the determination and diagnostic validation of brain death the law requires either two EEG recordings separated by a 4-hour observation period, both showing electrocerebral inactivity; or cerebral angiography examination. Since EEG is available in most hospitals and clinics, it is often used in this indication, at the patient's bedside, especially in the context of organ donation. However, very precise methodology must be followed. The last French guidelines date back to 1989, before the development of digital EEG recording. We present the new guidelines from the Société de Neurophysiologie Clinique de Langue Française. Electrocerebral inactivity may be confirmed when a 30-minute good quality EEG recording shows complete electrocerebral silence, defined as no cerebral activity greater than 2 uV, having first ruled out the possible influence of sedative drugs, metabolic disorders or hypothermia. In the presence of sedative drugs, CT brain angiography will be the gold standard test for this diagnosis. In the newborn, the utmost caution is indicated since electrocerebral inactivity can be observed in the absence of cerebral death. In the infant, the criterion for the observation period to be respected between both EEG recordings needs to be more clearly refined.
- [Study on propofol and fentanyl administrated via common carotid artery in rabbits]. [Journal Article]
- ZYZhonghua Yi Xue Za Zhi 2013 Oct 08; 93(37):2997-9
- CONCLUSIONS: Compared to drugs infusion via the ear vein, infusion of propol and fentanyl via the common carotid artery is more advantageous in some aspects, such as rapid anesthesia induction and recovery, smaller dose, and smaller impact on the hemodynamic and respiratory.
- A rapid course through the five electrographic stages of status epilepticus. [Case Reports]
- EEpilepsia 2012; 53(11):e193-5
- A 54-year-old woman was transferred to a university hospital for severe sepsis and multiorgan failure. A complex partial seizure was noted and she was placed on continuous electroencephalography (EEG…
A 54-year-old woman was transferred to a university hospital for severe sepsis and multiorgan failure. A complex partial seizure was noted and she was placed on continuous electroencephalography (EEG). During EEG monitoring she developed generalized convulsive status epilepticus. After consultation with family it was decided not to escalate treatment due to her overall medical condition. She proceeded sequentially through the five stages of status epilepticus, described by Treiman et al. (1990) over 22 h and 30 min and then developed electrocerebral silence. This case is significant in that it is the first report of a single individual experiencing all five stages of status epilepticus displayed on a continuous EEG. The case further demonstrates the rapid progression of status epilepticus and exemplifies the need for prompt treatment.
- [Communication with the relatives of a patient presumed brain dead]. [Case Reports]
- NTNed Tijdschr Geneeskd 2011; 155(18):A3404
- CONCLUSIONS: A patient is dead after complete brain death determination or after circulatory arrest. Loss of consciousness (Glasgow Coma score of 3) and absence of brain stem reflexes lead to a state of catastrophic cerebral damage, but not to brain death. In such a situation, wording such as 'brain death', 'deceased' and 'clinical brain death' should be avoided in conversations with the relatives.
New Search Next
- EMG artifact in brain death electroencephalogram, is it a cry of "medullary death"? [Case Reports]
- CNClin Neurol Neurosurg 2008; 110(7):729-31
- The Uniform Determination of Death Act (UDDA) defines death as irreversible cessation of the functions of the entire brain including the brainstem. Many individuals meeting the clinical criteria of b…
The Uniform Determination of Death Act (UDDA) defines death as irreversible cessation of the functions of the entire brain including the brainstem. Many individuals meeting the clinical criteria of brain death can be documented to have some residual sub-cortical and brainstem function on careful testing. Determination of brain death still remains a persistently unresolved issue in health law and bioethics. The determination of brain death is clinical and involves testing for the integrity of brainstem functions. Documentation of irreversible cessation of brainstem functions when the cause of coma is established is usually sufficient to make a diagnosis of brain death. Confirmatory tests like four-vessel angiogram and electroencephalogram (EEG) are required in cases where the clinical testing is inconclusive or unreliable. EEG criteria for electrocerebral silence (ECS) is absence of any detectable cortical activity above 2 microV in a study performed as per the guidelines developed by the American Electroencephalographic Society. EEG studies carried out for ECS are at times contaminated by electromyographic (EMG) artifacts reflecting scalp motor unit activity. A secure EEG diagnosis of ECS cannot be made in such cases. What exactly is the relevance of scalp EMG activity in these clinically brain dead patients? What is the mechanism of generation of this spontaneous scalp EMG activity and how can the diagnosis of brain death be secured in these patients? These issues are explored in this article by highlighting a case.