Search

Cardiac arrest survivors suffer the repercussions of anoxic brain injury, a critical factor influencing long-term prognosis. This injury is characterised by profound and enduring metabolic impairment. Ketone bodies, an alternative energetic resource in physiological states such as exercise, fasting, and extended starvation, are avidly taken up and used by the brain. Both the ketogenic diet and exogenous ketone supplementation have been associated with neuroprotective effects across a spectrum of conditions. These include refractory epilepsy, neurodegenerative disorders, cognitive impairment, focal cerebral ischemia, and traumatic brain injuries. Beyond this, ketone bodies possess a plethora of attributes that appear to be particularly favourable after cardiac arrest. These encompass anti-inflammatory effects, the attenuation of oxidative stress, the improvement of mitochondrial function, a glucose-sparing effect, and the enhancement of cardiac function. The aim of this manuscript is to appraise pertinent scientific literature on the topic through a narrative review. We aim to encapsulate the existing evidence and underscore the potential therapeutic value of ketone bodies in the context of cardiac arrest to provide a rationale for their use in forthcoming translational research efforts.

Emerging science continues to establish the detrimental effects of malnutrition in acute neurological diseases such as traumatic brain injury, stroke, status epilepticus and anoxic brain injury. The primary pathological pathways responsible for secondary brain injury include neuroinflammation, catabolism, immune suppression and metabolic failure, and these are exacerbated by malnutrition. Given this, there is growing interest in novel nutritional interventions to promote neurological recovery after acute brain injury. In this review, we will describe how malnutrition impacts the biomolecular mechanisms of secondary brain injury in acute neurological disorders, and how nutritional status can be optimized in both pediatric and adult populations. We will further highlight emerging therapeutic approaches, including specialized diets that aim to resolve neuroinflammation, immunodeficiency and metabolic crisis, by providing pre-clinical and clinical evidence that their use promotes neurologic recovery. Using nutrition as a targeted treatment is appealing for several reasons that will be discussed. Given the high mortality and both short- and long-term morbidity associated with acute brain injuries, novel translational and clinical approaches are needed.

Abstract This article highlights the possibility of positive outcomes associated with prolonged CPR and anoxic brain injury contesting the idea that such patients will invariably end up in a persistent vegetative state.

Abstract Emergency clinicians often resuscitate cardiac arrest patients, and after acute resuscitation, clinicians face multiple decisions regarding disposition. Recent evidence suggests that out‐of‐hospital cardiac arrest patients with return of spontaneous circulation have higher odds of survival to hospital discharge, long‐term survival, and improved functional outcomes when treated at centers that can provide advanced multidisciplinary care. For community clinicians, a high volume cardiac arrest center may be hours away. While current guidelines recommend against neurological prognostication in the first hours or days after return of spontaneous circulation, there are early findings suggestive of irrecoverable brain injury in which the patient would receive no benefit from transfer. In this Concepts article, we describe a simplified approach to quickly evaluate neurological status in cardiac arrest patients and identify findings concerning for irrecoverable brain injury. Characteristics of the arrest and resuscitation, initial neurological assessment, and brain computed tomography together can identify patients with high likelihood of irrecoverable anoxic injury. Patients who may benefit from centers with access to continuous electroencephalography are discussed. This approach can be used to identify patients who may benefit from rapid transfer to cardiac arrest centers versus those who may benefit from care close to home. Risk stratification also can provide realistic expectations for recovery to families.

Background: Electroencephalography (EEG) is commonly used after cardiac arrest. Burst suppression with identical bursts (BSIB) has been reported as a perfectly specific predictor of poor outcome but published case series are small. We describe two patients with BSIB who awakened from coma after cardiac arrest. Methods: We identified two out-of-hospital cardiac arrest (OHCA) patients with coma and BSIB. We determined the etiology of arrest, presenting neurological examination, potential confounders to neurological assessment, neurodiagnostics and time to awakening. We reviewed and interpreted EEGs using 2021 American Clinical Neurophysiology Society guidelines. We quantified identicality of bursts by calculating pairwise correlation coefficients between the first 500 ms of each aligned burst. Results: In case one we present a 62-year-old man with OHCA secondary to septic shock. EEG showed burst suppression pattern, with bursts consisted of high amplitude generalized spike waves in lock-step with myoclonus (inter-burst correlation = 0.86). He followed commands 3 days after arrest, when repeat EEG showed a continuous, variable and reactive background without epileptiform activity. Case two was a 49-year-old woman with OHCA secondary to polysubstance overdose. Initial EEG revealed burst suppression with high amplitude generalized polyspike-wave bursts with associated myoclonus. She followed commands on post-arrest day 4, when repeat EEG showed a continuous, variable and reactive background with frequent runs of bifrontal predominant sharply contoured rhythmic delta activity. Conclusion: These cases highlight the perils of prognosticating with a single modality in comatose cardiac arrest patients.

Anoxic brain injury (ABI) is an important cause of prolonged hospital stay and morbidity across the globe. It is a sequel of major systemic insults resulting from various etiologies, such as reduced oxygen availability, insufficient cerebral blood flow, reduced oxygen carriage, or any metabolic condition that can interfere with the utilization of oxygen. A varying combination of pathophysiologic mechanisms leads to a spectrum of clinical manifestations, the understanding of which will significantly help in prognostication of patients. Neuroprognostication helps both the clinician and the patient's family in planning future course and is further aided by various neuromonitoring modalities, biomarkers, and imaging. Targeted temperature management still remains a therapeutic tool in ABI and along with other neuroprotective measures may improve the survival. Continuing research in ABI may uncover more promising treatment strategies.

This is a retrospective study to investigate the results of using zolpidem and lorazepam in persons with disorders of consciousness (DoC) and to provide practical information for clinical application and further studies. The cohort included 146 patients (11 hemorrhagic stroke, 87 traumatic brain injury (TBI), 48 anoxic brain injury (ABI)) admitted to a specialized DoC rehabilitation program. A positive trial indicated a patient responded to either zolpidem or lorazepam with prominent functional improvements necessitating routine use of the medication. Non-responders had equivocal or negative (i.e., went to sleep) responses. Eleven patients with a stroke who had either medication were all non-responders. Of the remaining 135 patients, 95 received at least one medication trial. The overall positive rate was 11.6% (11/95), with 6.3% (5/79) for zolpidem and 14.0% (6/43) for lorazepam. Among TBI patients, the positive rate of the zolpidem trial (10.2%, 5/49) was slightly higher than that of the lorazepam trial (6.9%, 2/29; p > 0.05). Among ABI patients, the positive rate of the lorazepam trial (28.6%, 4/14) was significantly higher than that of the zolpidem trial (0%, 0/30; p = 0.007). Following a positive trial, most patients were continued on the medications on a regular basis before eventual discontinuation. Our results suggested the etiology of DoC, considering traumatic vs. anoxic injuries, may serve in guiding the clinical application of these medications in the treatment of DoC and in future prospective studies. We advocate for screening all patients with DoC using zolpidem and/or lorazepam.

A 63-year-old woman was hospitalized for rehabilitation from the aftereffects of an anoxic brain injury. In addition to a general cognitive decline, agraphia of kana and kanji was noted at the time of admission, which had advanced to agraphia which is dominant in kanji at the time of hospital discharge. Brain magnetic resonance imaging revealed no stroke lesions, and brain perfusion scintigraphy found a decreased blood flow in the bilateral parietal lobes. We hereby report on this case because case reports on agraphia caused by anoxic brain injury are extremely rare.

Drowning is a leading cause of neurological morbidity and mortality in young children. Anoxic brain injury (ABI) can result from nonfatal drowning and typically entails substantial neurological impairment. The neuropathology of drowning-induced pediatric ABI is not well established. Specifically, quantitative characterization of the spatial extent and tissue distribution of anoxic damage in pediatric nonfatal drowning has not previously been reported but could clarify the underlying pathophysiological processes and inform clinical management. To this end, we used voxel-based morphometric (VBM) analyses to quantify the extent and spatial distribution of consistent, between-subject alterations in gray and white matter volume. Whole-brain, high-resolution T1-weighted MRI datasets were acquired in 11 children with chronic ABI and 11 age- and gender-matched neurotypical controls (4–12 years). Group-wise VBM analyses demonstrated predominantly central subcortical pathology in the ABI group in both gray matter (bilateral basal ganglia nuclei) and white matter (bilateral external and posterior internal capsules) (P

Out-of-hospital cardiac arrest (CA) remains a leading cause of sudden morbidity and mortality; however, outcomes have continued to improve in the era of targeted temperature management (TTM). In this review, we highlight the clinical use of TTM, and provide an updated summary of multimodality monitoring possible in a modern ICU. TTM is neuroprotective for survivors of CA by inhibiting multiple pathophysiologic processes caused by anoxic brain injury, with a final common pathway of neuronal death. Current guidelines recommend the use of TTM for out-of-hospital CA survivors who present with a shockable rhythm. Further studies are being completed to determine the optimal timing, depth and duration of hypothermia to optimize patient outcomes. Although a multidisciplinary approach is necessary in the CA population, neurologists and neurointensivists are central in selecting TTM candidates and guiding patient care and prognostic evaluation. Established prognostic tools include clinal exam, SSEP, EEG and MR imaging, while functional MRI and invasive monitoring is not validated to improve outcomes in CA or aid in prognosis. We recommend that an evidence-based TTM and prognostication algorithm be locally implemented, based on each institution's resources and limitations. Given the high incidence of CA and difficulty in predicting outcomes, further study is urgently needed to determine the utility of more recent multimodality devices and studies.

Integrated post-resuscitation treatment has improved the outcome of the unconscious patients with cardiac arrest after introduction of the therapeutic hypothermia, which had shown promising results in the two pivotal randomized trials. Early assessment of neurological function and prognostication in these comatose patients has been challenging problem, and the introduction of therapeutic hypothermia made the problem more confusing. Various clinical situations, the results of the clinical neurologic examination, neurophysiologic monitoring including electroencephalography and somatosensory evoked potentials, various biomarkers, and neuroimaging can be used in predicting early prognosis. No single test is allowed to predict the prognosis with certainty, and a multimodal strategy is generally recommended. The previous practice guideline of the American Academy of Neurology in 2006 may not be appropriate anymore in the era of therapeutic hypothermia. In this review, the author introduces various neuromonitoring methods currently used in the therapeutic hypothermia and evaluate the their role in the prognostication with available evidences.