Anoxic-ischemic Encephalopathy Research Articles

Risk factors for mortality of preterm infants in the neonatal medicine department of the ‘Mère-Enfant’ University Hospital Centre of Libreville

Background: Reducing neonatal mortality of preterm infants is a public health priority in developing countries. The objective of this study was to study the risk factors for mortality of preterm infants in the neonatology department of UHCME-JEF. Methods: A retrospective, analytical study was done over 36 months (January 2019-December 2021) in the neonatology department of UHCME-JEF. Maternal and newborn parameters were studied. All hospitalized preterm newborns were included. Results: The prevalence of prematurity was 44.6%. The mortality rate was 18.7%. The mean age of mothers was 28.05±6.5 years. They were unemployed (69.4%) and single (73.6%). The three main causes of death were sepsis (41.7%), respiratory failure (26.0%), and anoxic-ischemic encephalopathy (15.3%). The risk factors associated with death were multiparity [p=0.001, OR=2.0, IC 95% (1.32-3.00)], pre-existing maternal diabetes [p=0.007, OR=2.4, IC 95% (1.31-4.52)], prenatal check-up not done [p=0, 024, OR=1.5 IC 95% (1.04-2.05)], GA<28SA [p<0.001, OR=1.8 IC 95% (1.24 -2.71)], Apgar <3 at the first [p=0.036, OR=1.8, IC 95% (1.21-2.76)] and fifth minute [p=0.010, OR=3.2, IC 95% (1.35-7.74)] resuscitation at birth [p=0.017, OR=1.5, IC 95% (1.04-2.05)], birth weight <1000 g (p=0.001, OR=2.8, IC 95% (1.92-4.23)], hypotonia [p=0.001, OR=1.6, IC 95% (1.23-2.32)], asphyxia [p=0.020, OR=1.7 CI 95% (1.09-2.55)], hypothermia [p<0.001, OR=2.1, CI 95% (1.56-2.86)], the presence of thrombocytopenia [p=0.001, OR=1.9, CI 95% (1.62-2.93)] and glycemic dysregulation [p=0.001, OR=2.8, CI 95% (2.09-3.73)]. Conclusions: The mortality of preterm newborns remains a major problem in our department. It is necessary to promote good surveillance of pregnancy, and correct care of premature infants in the delivery room and hospitalization.

Brain networks involved in generalized periodic discharges (GPD) in post-anoxic-ischemic encephalopathy

AimGeneralized periodic discharge (GPD) is an EEG pattern of poor neurological outcome, frequently observed in comatose patients after cardiac arrest. The aim of our study was to identify the neuronal network generating ≤2.5 Hz GPD using EEG source localization and connectivity analysis. MethodsWe analyzed 40 comatose adult patients with anoxic-ischemic encephalopathy, who had 19 channel-EEG recording. We computed electric source analysis based on distributed inverse solution (LAURA) and we estimated cortical activity in 82 atlas-based cortical brain regions. We applied directed connectivity analysis (Partial Directed Coherence) on these sources to estimate the main drivers. ResultsSource analysis suggested that the GPD are generated in the cortex of the limbic system in the majority of patients (87.5%). Connectivity analysis revealed main drivers located in thalamus and hippocampus for the large majority of patients (80%), together with important activation also in amygdala (70%). ConclusionsWe hypothesize that the anoxic-ischemic dysfunction, leading to hyperactivity of the thalamo-cortical (limbic presumably) circuit, can result in an oscillatory thalamic activity capable of inducing periodic cortical (limbic, mostly medial-temporal and orbitofrontal) discharges, similarly to the case of generalized rhythmic spike-wave discharge in convulsive or non-convulsive status epilepticus.

Early Functional Connectome Integrity and 1-Year Recovery in Comatose Survivors of Cardiac Arrest.

Purpose To assess whether early brain functional connectivity is associated with functional recovery 1 year after cardiac arrest (CA). Materials and Methods Enrolled in this prospective multicenter cohort were 46 patients who were comatose after CA. Principal outcome was cerebral performance category at 12 months, with favorable outcome (FO) defined as cerebral performance category 1 or 2. All participants underwent multiparametric structural and functional magnetic resonance (MR) imaging less than 4 weeks after CA. Within- and between-network connectivity was measured in dorsal attention network (DAN), default-mode network (DMN), salience network (SN), and executive control network (ECN) by using seed-based analysis of resting-state functional MR imaging data. Structural changes identified with fluid-attenuated inversion recovery and diffusion-weighted imaging sequences were analyzed by using validated morphologic scales. The association between connectivity measures, structural changes, and the principal outcome was explored with multivariable modeling. Results Patients underwent MR imaging a mean 12.6 days ± 5.6 (standard deviation) after CA. At 12 months, 11 patients had an FO. Patients with FO had higher within-DMN connectivity and greater anticorrelation between SN and DMN and between SN and ECN compared with patients with unfavorable outcome, an effect that was maintained after multivariable adjustment. Anticorrelation of SN-DMN predicted outcomes with higher accuracy than fluid-attenuated inversion recovery or diffusion-weighted imaging scores (area under the receiver operating characteristic curves, respectively, 0.88, 0.74, and 0.71). Conclusion MR imaging-based measures of cerebral functional network connectivity obtained in the acute phase of CA were independently associated with FO at 1 year, warranting validation as early markers of long-term recovery potential in patients with anoxic-ischemic encephalopathy. © RSNA, 2017.

P331 Clinical and electroencephalography role in prediction of outcome in survivors after cardiopulmonary resuscitation

Objective To outline the reliable predictors of both favorable and unfavorable outcomes of anoxic-ischemic encephalopathy. Subjects Forty patients from National Heart Institute Hospital who regained spontaneous circulation after cardiac arrest classified into 2 groups according to outcome, group A (favorable outcome), and group B (unfavorable outcome). Methods All patients were subjected to digital EEG, QEEG and clinical assessment at Day 1, 3 and 7 from restoration of spontaneous circulation. The results were compared, and correlated with neurological outcome. Results The mean of age was 54.6 ± 11.9 years (range, 26–70 years). Eighteen patients (45%) were discharged after recovery and twenty-two patients (55%) died in CCU. The survivred patients had relatively shorter CPR time 9.4 ± 7.8 min, compared to the dead patients16.6 ± 10.6 min. Alteration in the mental state was significantly higher in patient with poor outcome within Day 3 compared to patients with good outcome, ( P = 0.000). Failure to regain brainstem reflexes after 72 h was a significant predictor of poor outcome, ( P = 0.003). Failure to have EEG background reactivity in Day 1 or regain it in Day 3 was a significant predictor of poor outcome, ( P = 0.004, 0.003 respectively). The sensitivity and specificity for poor outcome for amplitude of O1 higher than 2.7 was 63.3% and 44.4% respectively, O2 higher than 2.4 was 68.2% and 44.4% respectively and Cz higher than 1.5 was 68.2% 50% respectively. In conclusion The correlation between EEG data and global functional outcome are possibly confident within 72 h.

Neuroprognostication after cardiac arrest in the light of targeted temperature management.

Delayed awakening after targeted temperature management (TTM) and sedation is frequent among cardiac arrest patients. Differentiating between prolonged coma and irreversible cerebral damage can be challenging, therefore the utilization of a multimodal approach is recommended by international guidelines. Here, we discuss indications and advantages/disadvantages of available modalities for coma prognostication and describe new tools to improve our accuracy for outcome prediction. Studies from the TTM era confirmed that combining neurological examination with electrophysiological assessment [electroencephalography (EEG) and somato-sensory evoked potentials (SSEP)] greatly improves coma prognostication. This combination is nowadays recognized as the most useful by many clinicians and appears widely applicable as part of initial patient assessment. Additional tests (serum neuron specific enolase and neuroimaging) may be most useful to orient clinical decisions in patients with prolonged coma. Advanced analysis of EEG and SSEP recordings and the emergence of quantitative pupillometry hold great promise. Multimodal prognostication offers a comprehensive approach of anoxic-ischemic encephalopathy and is increasingly used in postresuscitation care. Worldwide implementation and future advancements of available modalities, together with the increasing use of novel automated devices for quantitative neurological examination, may further optimize prognostic accuracy in the early ICU phase following cardiac arrest.

Chapter 21 - Determinants of prognosis in neurocatastrophes

A neurocatastrophe or severe brain injury (SBI) is a central nervous system insult associated with a high likelihood of death or severe disability. While many etiologic processes may lead to SBI, the most common and best-studied clinical paradigms are traumatic brain injury and anoxic-ischemic encephalopathy following cardiac arrest. Clinical phenotypes following SBI include acute and chronic disorders of consciousness as well as a range of cognitive and behavioral impairments. A fundamental task for medical teams working in the acute phase is to estimate SBI recovery probabilities with the highest degree of accuracy possible. Predictions made on the basis of single features or variables lack discrimination and are generally supplanted by multivariable models that combine clinical, imaging, and laboratory data into tractable scoring systems. Yet existing scores fail to classify outcomes with the accuracy that would support individual patient-level decision making. Improved prognostication will likely depend on the use of molecular and imaging data that capture unique biologic features in individual patients with SBI. The integration of these additional layers of information will require iterative computational approaches.

Hypoxia and Outcome Prediction in Early-Stage Coma (Project HOPE): an observational prospective cohort study.

BackgroundThe number of resuscitated cardiac arrest patients suffering from anoxic-ischemic encephalopathy is considerable. However, outcome prediction parameters such as somatosensory evoked potentials need revision because they are based on data predating the implementation of mild therapeutical hypothermia and because data from our own laboratory suggest that they may fail to predict prognosis accurately. The present research project “Hypoxia and Outcome Prediction in Early-Stage Coma” is an ongoing observational prospective cohort study that aims to improve outcome prediction in anoxic coma by limiting the effects of falsely pessimistic predictions at the intensive care unit.MethodsOur outcome analysis is based on functional and behavioural definitions. This implies the analysis of the positive predictive value of prognostic markers yielding either positive or negative results. We also analyse the effect of covariates adjusted for age and sex such as sociodemographic variables, prognostic variables and treatment factors on functional and behavioural outcomes, with mixed effects regression models (i.e. fixed and random effects). We expect to enrol 172 patients based on the result of previous research. The null hypothesis is that there is a probability of <10 % that a positive outcome will be observed despite the presence of any of the predictors of a poor/negative outcome. We test the null hypothesis against a one-sided alternative using a Simon’s two-stage design to determine whether it is warranted to recruit the full number of patients suggested by a power analysis. The second stage has a design with a Type I error rate of 0.05 and 80 % power if the true response rate is 25 %.DiscussionWe aim to make a significant contribution to the revision and improvement of current outcome prediction methods in anoxic-ischemic encephalopathy patients. As a result, neurocritical care specialists worldwide will have considerably more accurate methods for prognosticating the outcome of anoxic-ischemic encephalopathy following cardiac arrest. This will facilitate the provision of treatment tailored to individual patients and the attainment of an optimal quality of life. It will also inform the decision to withdraw treatment with a level of accuracy never seen before in the field.Trial registrationClinicalTrials.gov NCT02231060 (registered 29 August 2014)

Therapeutic hypothermia does not diminish the vital and necessary role of SSEP in predicting unfavorable outcome in anoxic-ischemic coma

Rational medical management of patients who remain comatose following cardio-pulmonary resuscitation (CPR) due to anoxic-ischemic encephalopathy depends upon the early identification of those with a hopeless prognosis – regardless of how aggressively they are managed. Conversely, it is mandatory that we recognize those patients with the potential to recover in order to institute aggressive therapeutic measures. The bilateral absence of the N20 Cortical Somatosensory Evoked Potential has been identified as the most reliable predictor of an unfavorable prognosis in normothermic patients.Two randomized trials have determined that mild therapeutic hypothermia (TH) delivered immediately after CPR improves neurologic outcomes. TH has now become the standard of care in the management of patients with cardio-pulmonary arrest. Eight studies targeting patients who were comatose following CPR, treated with TH, and using SSEP as an outcome predictor are reviewed. There is only one patient treated with TH who appears to have fully recovered following cardiac arrest who was initially found to have bilateral absent cortical potentials. This opinion paper will address whether the criteria that placed reliance upon SSEP to predict unfavorable outcome in post cardio-pulmonary arrest patients after receiving TH, still apply.

The role of middle latency evoked potentials in early prediction of favorable outcomes among patients with severe ischemic brain injuries

ObjectiveTo explore the role of middle latency evoked potentials (EPs) as predictors for favorable outcome in patients with severe ischemic brain injuries by comparing the prognostic ability of short latency somatosensory and auditory evoked potentials (SLSEP and BAEP) with middle latency somatosensory and auditory evoked potentials (MLSEP and MLAEP). MethodsMLSEP, MLAEP, SLSEP and BAEP were recorded in 112 patients with severe ischemic brain injuries (Glasgow Coma Scale≤8). Among them, 83 patients suffered from cerebral ischemic stroke and 29 suffered from anoxic–ischemic encephalopathy after cardiopulmonary resuscitation between 1 and 7days after the onset of stroke. Outcomes were reviewed 6months later using the Glasgow Outcome Scale (GOS). A GOS score of 4–5 was considered as a good outcome while a score of 1–3 was considered as poor. ResultsBy using the prognostic authenticity analysis of predictors for good outcome, at least unilateral N20 of the SLSEP exit and at least unilateral N60 of the MLSEP exit showed the highest sensitivity which was 100% (95% CI: 86.7%–100%). The bilateral normal N60 showed a high specificity of 97.5% (95% CI: 90.4%–99.6%). It also showed the highest positive likelihood ratio of 6.25% (95% CI: 1.28%–30.59%), which was superior to N20 of SLSEP, V of BAEP, and Pa of MLAEP. The analysis demonstrated that the area under the curve for MLSEP grading was the highest (0.838) compared to that of SLSEP grading (0.784), MLAEP grading (0.659) and BAEP grading (0.621). ConclusionsCompared with using N20 of SLSEP analysis alone, adding MLSEP improves the outcome prediction in patients with severe ischemic brain injuries. When an outcome is uncertain after initial evaluation using short-latency EPs, MLSEP is valuable to be used from the first week to further improve prognostication in these patients.

MRI for coma emergence and recovery

Data from MRI can be used to generate detailed maps of central nervous system anatomy and functional activation. Here, we review new research that integrates advanced MRI acquisition and analysis to predict and track recovery following severe traumatic brain injury (TBI) or anoxic ischemic encephalopathy (AIE) following cardiac arrest. Diffusion tensor MRI studies of comatose TBI patients demonstrate specific distributions of white matter damage that are robustly associated with long-term functional outcomes. In unconscious patients with AIE, whole brain diffusion restriction has prognostic significance, as do regional changes in diffusion restriction or anisotropy. Results using functional MRI suggest that coma following TBI and cardiac arrest is associated with disconnections within cerebral architectures associated with arousal and conscious perception. The relation between these disconnections and postinjury recovery is being explored in ongoing cohorts. MRI of the brain is feasible in critically ill patients following TBI or cardiac arrest, revealing patterns of structural damage and functional disconnection that can help predict outcome in the long term. Prospective studies are needed to validate these findings and to identify relationships between MRI-defined alterations and specific postinjury cognitive and behavioural phenotypes.

Soins palliatifs en néonatologie : analyse et évolution des pratiques sur 5 ans dans un centre de niveau 3

The "Patients' rights and end-of-life care" act known as "Leonetti's Law" promulgated in 2005 has promoted the use of palliative care to avoid unreasonable obstinacy when life-sustaining treatment appears disproportionate. Very little is known about this new practice for newborns in French neonatal units. To describe and evaluate the practice of palliative care in the newborn (mode of entry, characteristics, and modalities) and its evolution over time. Ambispective observational study conducted in a level III neonatal center. We included all newborns presenting conditions for which palliative care was introduced. Quantitative and qualitative analyses of routinely collected data, recorded from medical and nursing charts. We compared the recorded data between periods P1 (2006-2007) and P2 (2008-2010) using the Chi(2) test to assess changes over time. A total of 93 newborns benefited from palliative care during the study period. The main medical conditions motivating palliative care initiation in the newborns were severe complications of prematurity (36/93, 39%), anoxic-ischemic encephalopathy (19/93, 20.5%), severe malformations (8/93, 8.5%), severe congenital heart disease (8/93, 8.5%), and other various etiologies (22/93, 23.5%). Both the number of newborns in palliative care/total number of births and the number of deaths after palliative care/total number of neonatal deaths remained stable. In case of prenatal diagnosis (n=31), there was an increase in the number of "palliative care from birth projects" (13/22 in P2 vs. 1/9 in P1, P=0.02). Collective meetings during the decision process were significantly more frequently reported in the infants' charts in P2 (48/59 in P2 vs. 18/34 in P1, P<0.01). Withdrawing and withholding life-sustaining treatment and limiting procedures of care and/or procedures of surveillance/monitoring were more frequent in P2 as compared to P1, respectively 12/34 vs. 37/59 (P=0.02) and 14/34 vs. 39/59 (P=0.03). A titration of level III analgesics treatment was high in both periods and remained stable. However, a trend toward an increase of systematic pain evaluation over time was observed (81.6% in P2 vs. 64.5% in P1; P=0.085). A significant number of newborns affected by various pathologies undergo neonatal palliative care. Despite their recent introduction in neonatal medicine, palliative care practices have changed significantly. These practices are mostly in compliance with the "patients' rights and end-of-life care" act promulgated in France in 2005.

Ethics and health policy of dialyzing a patient in a persistent vegetative state.

Each year, out-of-hospital cardiac arrests occur in approximately 300,000 Americans. Of these patients, less than 10% survive. Survivors often live with neurologic impairments that neurologists classify as anoxic-ischemic encephalopathy (AIE). Neurologic impairments under AIE can vary widely, each with unique outcomes. According to the American Academy of Neurology Practice Parameter paper, the definition of poor outcome in AIE includes death, persistent vegetative state (PVS), or severe disability requiring full nursing care 6 months after event. In a recent survey, participants deemed an outcome of PVS as "worse than dead." Lay persons' assessments of quality of life for those in a PVS provide assistance for surrogate decision-makers who are confronted with the clinical decision-making for a loved one in a PVS, whereas clinical practice guidelines help health care providers to make decisions with patients and/or families. In 2000, the Renal Physicians Association and the American Society of Nephrology published a clinical practice guideline, "Shared Decision-Making in the Appropriate Initiation of and Withdrawal from Dialysis." In 2010, after advances in research, a second edition of the guideline was published. The updated guideline confirmed the recommendation to withhold or withdraw ongoing dialysis in "patients with irreversible, profound neurological impairments such that they lack signs of thought, sensation, purposeful behavior and awareness of self and environment," such as found in patients with PVS. Here, the authors discuss the applicability of this guideline to patients in a PVS. In addition, they build on the guideline's conception of shared decision-making and discuss how continued dialysis violates ethical and legal principles of care in patients in a PVS.

Peut-on établir un pronostic neurologique à la sortie de la néonatalogie pour les encéphalopathies anoxo-ischémiques du nouveau-né à terme ?

Perinatal anoxic-ischemic encephalopathy affects about 2.5 per 1000 births and is associated with high mortality and long-term neurologic sequelae, somewhat alleviated by therapeutic hypothermia. In this context, the development of reliable and relevant prognostic tools is necessary to either adapt or limit therapeutic interventions. EEG performed at two or three days of life (DOL), diffusion weight MRI before DOL 7, conventional MRI during the first two weeks of life and clinical examination after rewarming best seem to meet these criteria.

Rationale and Design of the Prospective German Registry of Outcome in Patients With Severe Disorders of Consciousness After Acute Brain Injury

ObjectiveTo describe the rationale and design of a new patient registry (Koma Outcome von Patienten der Frührehabilitation–Register [KOPF-R; Registry for Coma Outcome in Patients Undergoing Acute Rehabilitation]) that has the scope to examine determinants of long-term outcome and functioning of patients with severe disorders of consciousness (DOC). DesignProspective multicenter neurologic rehabilitation registry. SettingFive specialized neurologic rehabilitation facilities. ParticipantsPatients (N=42) with DOC in vegetative state or minimally conscious state (MCS) as defined by the Coma Recovery Scale–Revised (CRS-R) after brain injury. Patients are being continuously enrolled. The data presented here cover the enrollment period from August 2011 to January 2012. InterventionsNot applicable. Main Outcome MeasuresCRS-R, FIM, and emergence from MCS. ResultsThe registry was set up in 5 facilities across the state of Bavaria/Germany with a special expertise in the rehabilitation of acquired brain injury. Inclusion of patients started in August 2011. Measures include sociodemographic and clinical characteristics, course of acute therapy, electrophysiologic measures (evoked potentials, electroencephalogram), neuron-specific enolase, current medication, functioning, cognition, participation, quality of life, quantity and characteristics of rehabilitation therapy, caregiver burden, and attitudes toward end-of-life decisions. Main diagnoses were traumatic brain injury (24%), intracerebral or subarachnoid hemorrhage (31%), and anoxic-ischemic encephalopathy (45%). Mean CRS-R score ± SD at admission to rehabilitation was 5.9±3.3, and mean FIM score ± SD at admission was 18±0.4. ConclusionsThe KOPF-R aspires to contribute prospective data on prognosis in severe DOC.

Perfil epidemiológico de la mortalidad tardía de los politraumatismos graves

ObjectiveA study is made of the epidemiology, chronogramand causes of late mortality in traumatized patients. DesignA prospective, observational cohort study of adult trauma patients was carried out. SettingsProvince of Guipúzcoa (Basque Country, Spain). Intensive care unit of a tertiary hospital. PatientsPatients with severe trauma (Injury Severity Score > 15), admitted to the ICU from January 1995 to December 2009, with late death (> 7 days). VariablesEpidemiological, laboratory test, hemodynamic and transfusional data were collected. Severity scores: Abbreviated Injury Scale (AIS) and ISS. ResultsPatients: 2003; ISS: 24.3±14.2. Total deaths: 405 (20%). Late mortality (>7 days): 102 (25.2%) patients, 9 years older and with a lower (18 points) ISS score than the patients who died early (48hours). Most frequent injuries: AIS-Head-Cervical spine ≥ 4 (52%); AIS-Abdomen ≥ 4 (19.6%); AIS-Chest ≥ 4 (11.7%); AIS-Extremities ≥ 4 (4.9%). Causes of death: 1) brain death (14.7%); 2) multiorgan failure (67.6%), in two injury contexts: a) severe brain trauma in the vegetative state and high spinal cord injuries with tetraplegia (35.3%); and b) non-neurological injuries (32.3%) with a high prevalence of hypovolemic shock, multiple transfusion and coagulopathy; 3) miscellaneous (10.7%): post-resuscitation anoxic-ischemic encephalopathy, pulmonary embolism and massive stroke; 4) non-evaluable (7%). ConclusionsAge, severity and type of injuries have an influence upon the time distribution and causality of late mortality. Brain death remains predominant, with multiorgan failure as the most frequent cause. This knowledge should contribute to the identification of problems, and to better organization of the structural and educational resources, thereby reducing the likely factors leading to death from trauma.

Clinical and imaging features of adult anoxic-ischemic encephalopathy after cardiopulmonary resuscitation

To explore the clinical and imaging features of anoxic-ischemic encephalopathy (AIE) patients after cardiopulmonary resuscitation. A total of 28 qualified AIE patients during the last decade from Xiangya Hospital, Central South University were recruited and analyzed retrospectively. The symptoms of status epilepticus, acute posthypoxic myoclonus, Lance-Adams syndrome, subarachnoid hemorrhage and cognitive deficits were observed. The abnormal findings of magnetic resonance imaging (MRI) or computed tomography (CT), involving neocortex, basal ganglia and para-ventricular white matter, were also recorded. During the early phase of disease, swollen cortex was present on MRI/CT. However, encephalatrophy appeared during the late phase. The more severe symptoms were observed, the more foci were present on MRI/CT. The etiologies of AIE patients are heterogeneous after cardiopulmonary resuscitation. The clinical symptoms and imaging studies are of prognostic significance.

The spectrum of neurological recovery.

The equivalence of brain death with death is largely, although not universally accepted. Patients may have suffered insults such as cardiac arrest, vascular catastrophe, poisoning, or head trauma. Early identification of patients at greatest risk of poor neurologic outcome and management in the appropriate critical care setting is the key to maximizing neurological recovery. Recent technological advances and neuroimaging have made it possible to predict neurological reversibility with great accuracy. Significant improvements in therapy such as hypothermia, will improve outcomes in neurological catastrophies, particularly in anoxic-ischemic encephalopathy. The clinical spectrum and diagnostic criteria of minimally conscious and vegetative states is reviewed. The current understanding of the differences in prognosis and prediction of meaningful cognitive and functional recovery in each neurological state is described. Establishing an understanding of the ethical principles that guide medical decisions in clinical practice related to different neurological states is evolving into a new field called neuroethics.

Application of Electrophysiologic Techniques in Poor Outcome Prediction Among Patients With Severe Focal and Diffuse Ischemic Brain Injury

To explore various electrophysiologic examinations as predictors for poor outcome in patients with severe ischemic brain injury, by comparing the prognostic ability of EEG, short-latency somatosensory evoked potentials (SLSEP), and brain stem auditory evoked potentials (BAEP). EEG, SLSEP, and BAEP were recorded in 161 patients with severe ischemic brain injuries (Glasgow Coma Scale ≤ 8), 77 with anoxic-ischemic encephalopathy after cardiopulmonary resuscitation, while 84 experienced massive hemispheric infarction at between 1 and 7 days after the onset. Outcomes were reviewed after 6 months using the Glasgow Outcome Scale. Six months after the onset, poor outcomes (Glasgow Outcome Scale, 1-2) were identified in 66 and 54 patients among the anoxic-ischemic encephalopathy and the massive hemispheric infarction group, respectively. By using the prognostic authenticity analysis of predictors, unfavorable EEG patterns, lack of EEG reactivity, pathologic N20 of SLSEP, and pathologic wave V of BAEP showed the high sensitivity (92.4%-97.0%, 95% confidence interval [CI]: 82.5%-99.5%), while bilateral absence of SLSEP N20 showed the highest specificity (100%, 95% CI: 67.9%-100%) and positive predictive value (100%, 95% CI: 90.4%-100%) in the anoxic-ischemic encephalopathy group. In the massive hemispheric infarction group, unfavorable EEG patterns showed the highest sensitivity (96.3%, 95% CI: 86.2%-99.4%) while bilateral absence of SLSEP N20 and BAEP wave V showed the highest specificity (100%, 95% CI: 85.9%-100%) and positive predictive value (100%, 95% CI: 80.8%-100%). The predictive power of electrophysiologic examinations is different according to the etiology of ischemic brain injury. Short-latency somatosensory evoked potentials (N20) can be considered the most powerful method to predict poor outcome in anoxic-ischemic encephalopathy. Combination of EEG (unfavorable EEG patterns) and SLSEP (N20)/BAEP (wave V) is best suited in massive hemispheric infarction to predict poor outcome.

Nonconvulsive status epilepticus and brain damage

Neurologists and intensivists have long debated whether nonconvulsive seizures (NCS) or bouts of nonconvulsive status epilepticus (NCSE) contribute to brain damage.1-3 It is generally acknowledged that convulsive status epilepticus leads to brain damage and that absence status epilepticus does not contribute to morphologic changes.4,5 Although there is abundant support that neuronal death, especially in the hippocampus, happens in animal models of NCS/NCSE,6-10 it has been difficult to establish this in humans. The difficulty concerns, at a minimum, evaluating the relative contribution of the etiologies and of seizures in NCS/NCSE as causes of brain damage. The conditions causing NCS and NCSE in the intensive care unit (ICU) setting include trauma, anoxic-ischemic encephalopathy, encephalitis, vascular lesions, neoplasms, metabolic disorders, sepsis, and preexisting epileptic conditions. Many of these in themselves are associated with significant tissue destruction in the cerebrum. How can …

Recovery of Awareness after Hyperacute Hepatic Encephalopathy with “Flat” EEG, Severe Brain Edema and Deep Coma

Hyperacute hepatic failure (HHF) has a high mortality rate that is most commonly due to severe cerebral edema. However, brain swelling and marked clinical and EEG suppression are potentially reversible, even though the same findings are associated with a very poor neurological outcome in anoxic-ischemic encephalopathy. We present three cases that illustrate neurological recovery despite severe brain swelling and loss of EEG activity. All patients recovered conscious awareness, including one who transiently lost cranial nerve reflexes. Despite deep coma, markedly suppressed EEG and brain edema, aggressive control of ICP may lead to good recovery in acute hepatic failure.