Risk factors of prognosis in older patients with severe brain injury after surgical intervention

BACKGROUND

Older patients (aged ≥ 60 years) with severe brain injury have a high mortality and disability rate. The objective of this retrospective study was to assess the clinical risk factors of prognosis in older patients with severe brain injury after surgical intervention and to analyze the prognosis of the surviving group of patients 1 year after discharge.

METHODS

Clinical data of older patients with severe brain injury who were admitted to two neurosurgical centers between January 2010 and December 2020 were collected. Patient age, sex, Glasgow Coma Scale (GCS) score at admission, underlying disease, mechanisms of injury, abnormal pupillary reflex, head computed tomography imaging findings (such as hematoma type),intraoperative brain swelling and other factors were reviewed. All the patients were categorized into a good prognosis (survival) group and a poor prognosis (death) group by the Glasgow Outcome Score (GOS); also, the related factors affecting the prognosis were screened and the independent risk factors were identified by the Binary logistic regression analysis. GOS was used to evaluate the prognosis of the surviving group of patients 1 year after discharge.

RESULTS

Out of 269 patients, 171 (63.6%) survived, and 98 (36.4%) died during hospitalization. Univariate analysis showed that age, GCS score at admission, underlying diseases, abnormal pupillary reflex, the disappearance of ambient cistern, the midline structure shift, intraoperative brain swelling, oxygen saturation < 90%, and cerebral hernia were risk factors for the prognosis of older patients with severe brain injury after surgical intervention. Multivariate analysis showed that age, underlying diseases, disappearance of ambient cistern, Oxygen saturation < 90% and intraoperative brain swelling were independent risk factors of the prognosis in the population. The effect of surgical intervention differed among various age groups at 1-year follow-up after surgery.

CONCLUSIONS

The results of this retrospective study confirmed that age, underlying diseases, disappearance of ambient cistern, intraoperative brain swelling, and oxygen saturation < 90% are associated with poor prognosis in older postoperative patients with severe brain injury. Surgical intervention may improve prognosis and reduce mortality in older patients (age < 75 years). But for those patients (age ≥ 75 years), the prognosis was poor after surgical intervention.

Interleukin-6 in Traumatic Brain Injury: A Janus-Faced Player in Damage and Repair

Traumatic brain injury (TBI) is a common and often devastating illness, with wide-ranging public health implications. In addition to the primary injury, victims of TBI are at risk for secondary neurological injury by numerous mechanisms. Current treatments are limited and do not target the profound immune response associated with injury. This immune response reflects a convergence of peripheral and central nervous system-resident immune cells whose interaction is mediated in part by a disruption in the blood-brain barrier (BBB). The diverse family of cytokines helps to govern this communication and among these, Interleukin (IL)-6 is a notable player in the immune response to acute neurological injury. It is also a well-established pharmacological target in a variety of other disease contexts. In TBI, elevated IL-6 levels are associated with worse outcomes, but the role of IL-6 in response to injury is double-edged. IL-6 promotes neurogenesis and wound healing in animal models of TBI, but it may also contribute to disruptions in the BBB and the progression of cerebral edema. Here, we review IL-6 biology in the context of TBI, with an eye to clarifying its controversial role and understanding its potential as a target for modulating the immune response in this disease.

Oatp (Organic Anion Transporting Polypeptide)-Mediated Transport: A Mechanism for Atorvastatin Neuroprotection in Stroke

BACKGROUND

Drug discovery for stroke is challenging as indicated by poor clinical translatability. In contrast, HMG-CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase inhibitors (ie, statins) improve poststroke neurological outcomes. This property requires transport across the blood-brain barrier via an endogenous uptake transporter (ie, Oatp1a4 [organic anion transporting polypeptide 1a4]). Our goal was to study Oatp1a4 as a drug delivery mechanism because the blood-brain barrier cannot be assumed to be completely open for all drugs in ischemic stroke.

METHODS

Male Sprague-Dawley rats (200-250 g) were subjected to middle cerebral artery occlusion (90 minutes) followed by reperfusion for up to 7 days. Atorvastatin (20 mg/kg, IV) was administered 2 hours following intraluminal suture removal. Involvement of Oatp-mediated transport was determined using fexofenadine (3.2 mg/kg, IV), a competitive Oatp inhibitor. Oatp1a4 transport activity was measured by in situ brain perfusion. Infarction volumes/brain edema ratios and neuronal nuclei expression were determined using 2,3,5-triphenyltetrazolium chloride-stained brain tissue slices and confocal microscopy, respectively. Poststroke functional outcomes were assessed via neurological deficit scores and rotarod analysis.

RESULTS

At 2-hour post-middle cerebral artery occlusion, [3H]atorvastatin uptake was increased in ischemic brain tissue. A single dose of atorvastatin significantly reduced post-middle cerebral artery occlusion infarction volume, decreased brain edema ratio, increased caudoputamen neuronal nuclei expression, and improved functional neurological outcomes. All middle cerebral artery occlusion positive effects of atorvastatin were attenuated by fexofenadine coadministration (ie, an Oatp transport inhibitor).

CONCLUSIONS

Our data demonstrate that neuroprotective effects of atorvastatin may require central nervous system delivery by Oatp-mediated transport at the blood-brain barrier, a mechanism that persists despite increased cerebrovascular permeability in ischemic stroke. These novel and translational findings support utility of blood-brain barrier transporters in drug delivery for neuroprotective agents.

Bacterial Meningitis With Cerebral Edema in a Young Adult: A Simulation Case for Medical Students

Introduction

Simulation in the preclinical medical education setting is a beneficial tool for students to develop clinical skills, supplement preexisting knowledge, and prepare for clinical rotations and beyond. We detail the complete simulation scenario, including a participant postresponse questionnaire, of a 28-year-old male who developed bacterial meningitis after experiencing an upper respiratory infection in the days prior.

Methods

Simulation fellows and faculty at the Alabama College of Osteopathic Medicine created a simulation scenario pertaining to bacterial meningitis. The scenario utilized a high-fidelity patient simulator, one standardized participant for patient voiceover, one standardized participant as a patient family member, and one standardized participant as a physician consultant on an as-needed basis. Sixteen preclinical medical students from various specialty interest groups were recruited to participate in the scenario and complete the postscenario questionnaire.

Results

The simulation scenario was well received by the participants, and 15 of 16 completed the postscenario questionnaire. Ninety-three percent strongly agreed the simulation was a valuable clinical experience. Additionally, 73% of participants strongly agreed that the simulation experience was realistic, 80% strongly agreed that it tested their clinical reasoning ability, and 53% strongly agreed it was appropriate for their level of clinical knowledge.

Discussion

Medical simulation is a valuable educational tool tailored to maximize student learning and supplement the traditional didactic curriculum. The successful development and implementation of our meningitis simulation case further supports the continued use of medical simulation in the preclinical setting.

Lauric acid provides neuroprotection against oxidative stress in mouse model of hyperglycaemic stroke

During ischemic stroke, higher glucose level linked worse outcomes were reported even in patients without pre-existing diabetes. Evidence suggest that such worse stroke outcomes were mainly due to production of reactive, toxic glucose metabolites that expands oxidative damage inside the brain. As a consequence of high oxidative stress, microvasculature structures and tight junctions compromised their functionally, infarct volume expands and brain edema exacerbates. In a mouse model of ischemic stroke with induced acute hyperglycaemia, Lauric acid (LA) as a natural saturated fatty acid demonstrated neuroprotection by attenuating infarct volume and brain edema. In addition, in the ipsilateral hyperglycaemic brain, the LA significantly increased the expression of tight junction representative protein (occludin) as well as anti-oxidative markers; Manganese superoxide dismutase (Mn) SOD, Extracellular superoxide dismutase (Ec-SOD) and nuclear factor-erythroid factor 2-related factor 2 (Nrf2) in the ipsilateral region against hyperglycemic ischemic stroke. LA treated animals showed a significant reduction in the production of lipid peroxidation products (4-HNE) in the microvascular structures, maintained the blood brain barrier (BBB) integrity. LA linked neuroprotective outcomes were further confirmed by behavioral tests, where functional outcomes and motor coordination were improved significantly. Furthermore, LA treatment enhanced food intake, decreased mortality rate, and net body weight loss. Conclusively, LA modulated ischemic insult exacerbated by hyperglycemia and provided neuroprotection.

Brain retraction injury: systematic literature review

Cerebral retraction is frequently required in cranial surgery to access deep areas. Brain retractors have been systematically used in the past, but they have been associated with brain injury. Nonetheless, they are still used and, even recently, new systems have been advocated. The aim of this study is to provide a systematic and critical review of brain retraction injury. A systematic literature review was performed in February 2023 according to PRISMA statement. Search terms included brain retraction and injury, with their variations and pertinent associations. Studies reporting qualitative and quantitative data on brain retraction injury were included. Out of 1689 initially retrieved articles, 90 and 26 were included in the systematic review for qualitative and quantitative data, respectively. The definition of brain retraction injury varies and its reported incidence in clinical studies is 5-10%, up to 47% if cerebral edema is considered. Some studies have hypothesized threshold values of pressures to be respected in order to prevent complications, with most data deriving from animal studies. At present, there are no instruments for brain retraction that can guarantee full safety. Some form of cerebral retraction might always be necessary for specific scenarios. Further studies are needed to collect quantitative and, ideally, clinical and comparative data on pressure thresholds to develop retraction systems that can reduce injury to a minimum.

Nicotine neurotoxicity exacerbation following engineered Ag and Cu (50-60 nm) nanoparticles intoxication. Neuroprotection with nanowired delivery of antioxidant compound H-290/51 together with serotonin 5-HT3 receptor antagonist ondansetron

Nicotine abuse is frequent worldwide leading to about 8 millions people die every year due to tobacco related diseases. Military personnel often use nicotine smoking that is about 12.8% higher than civilian populations. Nicotine smoking triggers oxidative stress and are linked to several neurodegenerative diseases such as Alzheimer's disease. Nicotine neurotoxicity induces significant depression and oxidative stress in the brain leading to neurovascular damages and brain pathology. Thus, details of nicotine neurotoxicity and factors influencing them require additional investigations. In this review, effects of engineered nanoparticles from metals Ag and Cu (50-60 nm) on nicotine neurotoxicity are discussed with regard to nicotine smoking. Military personnel often work in the environment where chances of nanoparticles exposure are quite common. In our earlier studies, we have shown that nanoparticles alone induces breakdown of the blood-brain barrier (BBB) and exacerbates brain pathology in animal models. In present investigation, nicotine exposure in with Ag or Cu nanoparticles intoxicated group exacerbated BBB breakdown, induce oxidative stress and aggravate brain pathology. Treatment with nanowired H-290/51 a potent chain-breaking antioxidant together with nanowired ondansetron, a potent 5-HT3 receptor antagonist significantly reduced oxidative stress, BBB breakdown and brain pathology in nicotine exposure associated with Ag or Cu nanoparticles intoxication. The functional significance of this findings and possible mechanisms of nicotine neurotoxicity are discussed based on current literature.

Increased brain microvascular hemoglobin concentrations in children with cerebral malaria

Brain swelling is associated with death from cerebral malaria, but it is unclear whether brain swelling is caused by cerebral edema or vascular congestion-two pathological conditions with distinct effects on tissue hemoglobin concentrations. We used near-infrared spectroscopy (NIRS) to noninvasively study cerebral microvascular hemoglobin concentrations in 46 Malawian children with cerebral malaria. Cerebral malaria was defined by the presence of the malaria parasite Plasmodium falciparum on a blood smear, a Blantyre coma score of 2 or less, and retinopathy. Children with uncomplicated malaria (n = 33) and healthy children (n = 29) were enrolled as comparators. Cerebral microvascular hemoglobin concentrations were higher among children with cerebral malaria compared with those with uncomplicated malaria [median (25th, 75th): 145.2 (95.2, 190.0) μM versus 82.9 (65.7, 105.4) μM, P = 0.008]. Cerebral microvascular hemoglobin concentrations correlated with brain swelling score determined by MRI (r = 0.37, P = 0.03). Fluctuations in cerebral microvascular hemoglobin concentrations over a 30-min time period were characterized using detrended fluctuation analysis (DFA). DFA determined self-similarity of the cerebral microvascular hemoglobin concentration signal to be lower among children with cerebral malaria compared with those with uncomplicated malaria [0.63 (0.54, 0.70) versus 0.91 (0.82, 0.94), P < 0.0001]. The lower self-similarity of the hemoglobin concentration signal in children with cerebral malaria suggested impaired regulation of cerebral blood flow. The elevated cerebral tissue hemoglobin concentration and its correlation with brain swelling suggested that excess blood volume, potentially due to vascular congestion, may contribute to brain swelling in cerebral malaria.

Effects of Gryllus bimaculatus and Oxya chinensis sinuosa extracts on brain damage via blood-brain barrier control and apoptosis in mice with pentylenetetrazol-induced epilepsy

The demand for environmentally friendly foods with high nutritional value and low carbon emissions is increasing with the aging of the global population and the crisis of food resources. Edible insects are becoming increasingly well-known as such foods. This study evaluated the effects and mechanisms of Gryllus bimaculatus (Cricket) (Gb) and Oxya chinensis sinuosa (Grasshopper) (Ocs) extracts on epilepsy. A pentylenetetrazol (PTZ)-induced seizure mouse model was used for the study, and Gb and Ocs extracts were administered for 29 days on alternate days at concentrations of 8 g/kg and 16 g/kg. The integrity of the blood-brain barrier (BBB) and brain edema was measured using the perfusion of Evans blue dye and brain water content. Gb and Ocs extracts prevented BBB permeabilization and cerebral edema through increasing the expression of tight junction-associated proteins in the endothelial cells and reducing water content in PTZ-treated mice. Additionally, Gb and Ocs extracts protected neurons from oxidative stress and apoptosis in different brain areas. These protective effects were demonstrated through the restoration of the expression of neuronal nuclear protein and postsynaptic density protein-95, thus increasing the levels of glutathione and superoxide dismutase, decreasing lipid peroxidation, and recovering apoptosis-associated proteins, such as Bax, cleaved PARP, and cleaved caspase-3, in epileptic mice. In addition, Gb and Ocs extracts rescued PTZ-induced hyperexcitable neurons to control mice level, as supported by the restored expression of gamma-aminobutyric acid (GABA) transporter 1, the metabotropic glutamate receptors-GRM2/3, and BDNF. This study suggested that Gb and Ocs extracts are novel medicinal candidates that can help ameliorate epilepsy by improving BBB health and preventing oxidative stress-mediated apoptosis.

Associations between multiple sclerosis and in-hospital outcomes of patients with hemorrhagic stroke

OBJECTIVE

To determine the influence of multiple sclerosis (MS) on in-hospital outcomes of patients with hemorrhagic strokes using a large, nationally representative database.

MATERIALS AND METHODS

This population-based, retrospective study extracted data of adults with hemorrhagic stroke from the US Nationwide Inpatient Sample (NIS) database from 2016 to 2018. Patients with/without MS were then compared. Hemorrhagic stroke and MS were identified by the International Classification of Diseases, Tenth editions (ICD-10) codes. In-hospital outcomes (i.e., in-hospital mortality, discharge destination, length of stay [LOS], total hospital cost, and major complications) were compared between subjects with and without MS using logistic regression analysis.

RESULTS

Among 107,573 patients with hemorrhagic stroke, 0.3% (n=337) had MS. After 1:10 propensity-score (PS) matching, 3,707 patients remained in the analytic sample. Multivariable analysis revealed that patients with MS had significantly shorter LOS (adjusted β=-1.34 days; 95% CI: -2.41 to -0.26, p=0.015), and lower total hospital costs (adjusted β=-28.82; 95% CI: -43.57 to -14.06, p<0.001) than those without MS. No significant different risks of any major complications, in-hospital mortality, or transfer to nursing homes/long-term care facilities were observed. For major complications, patients with MS had a significantly lower risk of cerebral edema than those without MS (adjusted odds ratio [aOR] = 0.66, 95%CI: 0.51 to 0.86, p =0.002) CONCLUSIONS: In hospitalized patients with hemorrhagic stroke, those with MS have shorter LOS, lower costs, and a lower risk of cerebral edema compared to no MS. More relevant experiments and studies are needed to confirm results of this study.

Promising Natural Medicines for the Treatment of High-Altitude Illness

Li Li, Lin Lin, Bo Wen, Peng-cheng Zhao, Da-sheng Liu, Guo-ming Pang, Zi-rong Wang, Yong Tan, and Cheng Lu. Promising natural medicines for the treatment of high-altitude illness. High Alt Med Biol. 24:175-185, 2023.-High-altitude illness (HAI) is a dangerous disease characterized by oxidative stress, inflammatory damage and hemodynamic changes in the body that can lead to severe damage to the lungs, heart, and brain. Natural medicines are widely known for their multiple active ingredients and pharmacological effects, which may be important in the treatment of HAI. In this review, we outline the specific types of HAI and the underlying pathological mechanisms and summarize the currently documented natural medicines applied in the treatment of acute mountain sickness and high-altitude cerebral edema, high-altitude pulmonary edema, chronic mountain sickness, and high-altitude pulmonary hypertension. Their sources, types, and medicinal sites are summarized, and their active ingredients, pharmacological effects, related mechanisms, and potential toxicity are discussed. In conclusion, natural medicines, as an acceptable complementary and alternative strategy with fewer side effects and more long-term application, can provide a reference for developing more natural antialtitude sickness medicines in the future and have good application prospects in HAI treatment.

Single-Cell RNA-Seq Reveals Changes in Cell Subsets in the Cortical Microenvironment during Acute Phase of Ischemic Stroke Rats

BACKGROUND

Ischemic stroke, the most common stroke type, has threatened human life and health. Currently, intravenous thrombolysis and endovascular thrombectomy are the mainstream treatment methods, but they may cause cerebral ischemia-reperfusion injury (CIRI), which aggravates brain injury. Consequently, it is worthwhile to start with a study of CIRI mechanism to identify better prevention and treatment methods. Applying single-cell RNA sequencing (scRNA-seq) technology to further understand the biological functions of various cell types in CIRI will facilitate the intervention of CIRI.

METHODS

This study aimed to establish a rat middle cerebral artery occlusion (MCAO) model to simulate cerebral ischemia-reperfusion, perform enzymatic hydrolysis, and suspend cerebral cortex tissue edema. Single-cell transcriptome sequencing was used, combined with cluster analysis, t-distributed stochastic neighbor embedding (t-SNE) visualization, and other bioinformatics methods to distinguish cell subgroups while using gene ontology (GO) function enrichment and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment to reveal the biological function of each cell subgroup.

RESULTS

We identified 21 brain clusters with cell type-specific gene expression patterns and cell subpopulations, as well as 42 marker genes representing different cell subpopulations. The number of cells in clusters 0-3 increased significantly in MCAO group compared to that in the sham group, and nine-cell subpopulations exhibited remarkable differences in the number of genes. Subsequently, GO and KEGG analyses were performed on the top 40 differentially expressed genes (DEGs) in the six cell subpopulations with significant differences. These results indicate that biological processes and signaling pathways are involved in different cell subpopulations.

CONCLUSIONS

ScRNA-seq revealed the diversity of cell differentiation and the unique information of cell subpopulations in the cortex of rats with acute ischemic stroke, providing novel insight into the pathological process and drug discovery in stroke.

After 3 months of medication balloon therapy, a patient who had contrast-induced encephalopathy recovered: A case report

RATIONALE

Iodinated contrast agents are extensively employed in clinical settings, with allergic reactions and renal impairment being the most prevalent adverse events. Contrast-induced encephalopathy (CIE) can present with heterogeneous clinical features, making diagnosis challenging. Prior studies on CIE have primarily documented rapid recovery within several days. However, this paper describes a case of CIE in a patient whose clinical symptoms took 3 months to fully abate.

PATIENT CONCERNS

A female patient, aged 54 years, received drug-coated balloon therapy for stenosis in a branch of the anterior descending coronary artery. Unfortunately, the patient developed CIE, which initially manifested as visual disturbances and subsequently progressed to gastrointestinal and limb movement issues, as well as an altered mental status, all of which occurred within a 24-hour period during hospitalization.

DIAGNOSES

The patient was diagnosed with CIE after cerebral hemorrhage, and cerebral edema was ruled out based on the history of contrast medium administration and radiographic exams.

INTERVENTIONS AND OUTCOMES

Dexamethasone (10 mg/d), mannitol (100 mL/d), betahistine (500 mL), trazodone (25 mg), and hydration supplementation were given to treat CIE-related symptoms. Aspirin and clopidogrel were administered for the management of the cardiovascular ailment. The neurologist prescribed neurotrophic agents, namely, cytarabine and methylcobalamin, based on the cerebral magnetic resonance imaging findings. Despite the treatment, the patient's ocular symptoms, including blurry vision, diplopia, and impaired intraocular retraction, persisted. Furthermore, the patient's mental state was altered, and she continued to exhibit a depressive state during her 1-month follow-up visit.

LESSONS

CIE is a comparatively infrequent ailment, and its prompt identification and management are of paramount importance. Although the treatments for CIE are primarily symptomatic, it is crucial to acknowledge that the symptoms may not always subside quickly within a short duration. In conjunction with pharmacotherapy, counseling should be offered to address patients' mental health.

Distinctions between the Koizumi and Zea Longa methods for middle cerebral artery occlusion (MCAO) model: a systematic review and meta-analysis of rodent data

Ischemic stroke in rodents is usually induced by intraluminal middle cerebral artery occlusion (MCAO) via the common carotid artery plugging filament invented by Koizumi et al. (MCAO-KM), or the external carotid artery plugging filament created by Zea Longa et al. (MCAO-LG). A systematic review of the distinctions between them is currently lacking. Here, we performed a meta-analysis in terms of model establishment, cerebral blood flow (CBF), and cerebral ischemia-reperfusion injury (CIRI) between them, Weighted Mean Differences and Standardized Mean Difference were used to analyze the combined effects, Cochrane's Q test and the I2 statistic were applied to determine heterogeneity, sensitivity analysis and subgroup analysis were performed to explore the source of heterogeneity. Literature mining suggests that MCAO-KM brings shorter operation time (p = 0.007), higher probability of plugging filament (p < 0.001) and molding establishment (p = 0.006), lower possibility of subarachnoid hemorrhage (p = 0.02), larger infarct volume (p = 0.003), severer brain edema (p = 0.002), and neurological deficits (p = 0.03). Nevertheless, MCAO-LG shows a more adequate CBF after ischemia-reperfusion (p < 0.001), a higher model survival rate (p = 0.02), and a greater infarct rate (p = 0.007). In conclusion, the MCAO-KM method is simple to operate with a high modeling success rate, and is suitable for the study of brain edema under long-term hypoperfusion, while the MCAO-LG method is highly challenging for novices, and is suitable for the study of CIRI caused by complete ischemia-reperfusion. These findings are expected to benefit the selection of intraluminal filament MCAO models before undertaking ischemic stroke preclinical effectiveness trials.

An Interesting Case of Severe Hyponatremia

ABSTRACT

In this report, we present an unusual and multifactorial case of severe hyponatremia with important clinical implications. The decedent was a 42-year-old woman who was discovered at her place of residence with altered mental status and profuse watery diarrhea. The scene was significant for numerous empty water bottles. She was transported to the emergency department of a local medical center and rapidly became obtunded. Imaging demonstrated cerebral edema with impending herniation. Serum chemistry was significant for severe hyponatremia (116 mEq/L) with decreased serum osmolality (245 mOsm/kg), suggestive of water overload. Over a brief course of hospitalization, she continued to deteriorate and brain death was pronounced. After brain death, she underwent organ donation. Subsequent autopsy examination demonstrated global cerebral edema with evidence of herniation. Toxicology examination of antemortem blood was positive for methamphetamine (1900 ng/mL) and amphetamine (100 ng/mL). An incidentally identified colon polyp was submitted for microscopic evaluation, which revealed the presence of Cryptosporidium , the likely cause of her diarrheal illness. Death was attributed to severe hyponatremia through the combined effects of excessive water consumption and loss of fluid and electrolytes from cryptosporidiosis, in turn leading to cerebral edema and brain herniation. Acute methamphetamine intoxication was a contributing condition.

Early Low Pulse Pressure in VA-ECMO Is Associated with Acute Brain Injury

BACKGROUND

Pulse pressure is a dynamic marker of cardiovascular function and is often impaired in patients on venoarterial extracorporeal membrane oxygenation (VA-ECMO). Pulsatile blood flow also serves as a regulator of vascular endothelium, and continuous-flow mechanical circulatory support can lead to endothelial dysfunction. We explored the impact of early low pulse pressure on occurrence of acute brain injury (ABI) in VA-ECMO.

METHODS

We conducted a retrospective analysis of adults with VA-ECMO at a tertiary care center between July 2016 and January 2021. Patients underwent standardized multimodal neuromonitoring throughout ECMO support. ABI included intracranial hemorrhage, ischemic stroke, hypoxic ischemic brain injury, cerebral edema, seizure, and brain death. Blood pressures were recorded every 15 min. Low pulse pressure was defined as a median pulse pressure < 20 mm Hg in the first 12 h of ECMO. Multivariable logistic regression was performed to investigate the association between pulse pressure and ABI.

RESULTS

We analyzed 5138 blood pressure measurements from 123 (median age 63; 63% male) VA-ECMO patients (54% peripheral; 46% central cannulation), of whom 41 (33%) experienced ABI. Individual ABIs were as follows: ischemic stroke (n = 18, 15%), hypoxic ischemic brain injury (n = 14, 11%), seizure (n = 8, 7%), intracranial hemorrhage (n = 7, 6%), cerebral edema (n = 7, 6%), and brain death (n = 2, 2%). Fifty-eight (47%) patients had low pulse pressure. In a multivariable model adjusting for preselected covariates, including cannulation strategy (central vs. peripheral), lactate on ECMO day 1, and left ventricle venting strategy, low pulse pressure was independently associated with ABI (adjusted odds ratio 2.57, 95% confidence interval 1.05-6.24). In a model with the same covariates, every 10-mm Hg decrease in pulse pressure was associated with 31% increased odds of ABI (95% confidence interval 1.01-1.68). In a sensitivity analysis model adjusting for systolic pressure, pulse pressure remained significantly associated with ABI.

CONCLUSIONS

Early low pulse pressure (< 20 mm Hg) was associated with ABI in VA-ECMO patients. Low pulse pressure may serve as a marker of ABI risk, which necessitates close neuromonitoring for early detection.

Melatonin ameliorates neurological deficits through MT2/IL-33/ferritin H signaling-mediated inhibition of neuroinflammation and ferroptosis after traumatic brain injury

Although traumatic brain injury (TBI) is a common cause of death and disability worldwide, there is currently a lack of effective therapeutic drugs and targets. To reveal the complex pathophysiologic mechanisms of TBI, we performed transcriptome analysis of the mouse cerebral cortex and immunohistochemical analysis of human cerebral tissues. The genes Mt1, Mt2, Il33, and Fth1 were upregulated post-TBI and enriched in pathways associated with the inflammatory response, oxidative phosphorylation, and ferroptosis. As an agonist of MT1/2, melatonin (MLT) confers anti-oxidant, anti-inflammatory, and anti-ferroptosis effects after TBI. However, whether these upregulated genes and their corresponding pathways are involved in the neuroprotective effect of MLT remains unclear. In this study, interventions to inhibit MT1/2, IL-33, and ferroptosis (i.e., ferritin H (Fth)-KO) were applied post-TBI. The results showed that MLT attenuated TBI-induced cerebral edema and neurological outcomes by inhibiting inflammation and ferroptosis. Mechanistically, MLT mainly suppressed inflammatory responses and ferroptosis via the activation of MT2 and IL-33 pathways. Building on the previous finding that Fth deletion increases susceptibility to ferroptosis post-TBI, we demonstrated that Fth depletion remarkably exacerbated the post-TBI inflammatory response, and abolished the anti-inflammatory effects of MLT both in vivo and in vitro. Furthermore, the post-TBI anti-inflammatory effect of MLT, which occurs by promoting the polarization of CD206⁺ macrophages, was dependent on Fth. Taken together, these results clarified that MLT alleviates inflammation- and ferroptosis-mediated brain edema and neurological deficits by activating the MT2/IL-33/Fth pathway, which provides a novel target and theoretical basis for MLT to treat TBI patients.

Multifaceted Roles of Aquaporins in the Pathogenesis of Alzheimer’s Disease

The central nervous system is highly dependent on water, and disturbances in water homeostasis can have a significant impact on its normal functions. The regulation of water balance is, at least in part, carried out via specialized water channels called aquaporins. In the central nervous system, two major aquaporins (AQPs), AQP1 and AQP4, and their potential involvements have been long implicated in the pathophysiology of many brain disorders such as brain edema and Neuromyelitis optica. In addition to these diseases, there is growing attention to the involvement of AQPs in the removal of waste products in Alzheimer’s disease (AD). This indicates that targeting fluid homeostasis is a novel and attractive approach for AD. This review article aims to summarize recent knowledge on the pathological implications of AQPs in AD, discussing unsolved questions and future prospects.

Malignant transformation of meningioma: Case report

RATIONALE

Meningiomas are mostly benign brain tumors with minimal malignant cases. Anaplastic meningioma has malignant morphological characteristics and a World Health Organization grade of III.

PATIENT CONCERNS

The present study reports a case of an occipital meningioma in a patient who initially chose observation and follow-up after diagnosis. The patient ultimately underwent surgery due to the enlargement of the tumor and the development of visual field defects after a decade of imaging follow-up. The postoperative pathology slides indicated the presence of an anaplastic meningioma (World Health Organization-grade III).

DIAGNOSES

The patient's diagnosis was established through cranial magnetic resonance imaging, which revealed an irregular mixed mass in the right occipital region with isointense T1 and hypointense T2 signal, irregular lobulation, and a maximum diameter of approximately 5.4 cm. Heterogenous enhancement was observed in the contrast-enhanced scan.

INTERVENTIONS

The patient opted for surgical intervention to remove the tumor, and the pathology slides of the tumor sample confirmed the diagnosis of anaplastic meningioma. The patient also received radiotherapy (40Gy/15fr).

OUTCOMES

No recurrence was observed during the 9-month follow-up.

LESSONS

This case highlights the potential for low-grade meningiomas to undergo malignant transformation, particularly in the presence of irregular lobulation, peritumoral brain edema, and heterogeneous enhancement on contrast-enhanced scans. Total excision (Simpson grade I) is the preferred treatment option, and long-term imaging follow-up is recommended.

Correcting Hypernatremia in Children

BACKGROUND

In children with hypernatremia, current clinical guidelines recommend a reduction in serum sodium of 0.5 mmol/L per hour or less to avoid complications of cerebral edema. However, no large-scale studies have been conducted in the pediatric setting to inform this recommendation. Therefore, this study aimed to report the association between the rate of correction of hypernatremia, neurological outcomes, and all-cause mortality in children.

METHODS

A retrospective cohort study was conducted from 2016 to 2019 at a quaternary pediatric center in Melbourne, Victoria, Australia. All children with at least one serum sodium level ≥150 mmol/L were identified through interrogation of the hospital's electronic medical record. Medical notes, neuroimaging reports, and electroencephalogram results were reviewed for evidence of seizures and/or cerebral edema. The peak serum sodium level was identified and correction rates over the first 24 hours and overall were calculated. Unadjusted and multivariable analyses were used to examine the association between the rate of sodium correction and neurological complications, the requirement for neurological investigation, and death.

RESULTS

There were 402 episodes of hypernatremia among 358 children over the 3-year study period. Of these, 179 were community-acquired and 223 developed during admission. A total of 28 patients (7%) died during admission. Mortality was higher in children with hospital-acquired hypernatremia, as was the frequency of intensive care unit admission and hospital length of stay. Rapid correction (>0.5 mmol/L per hour) occurred in 200 children and was not associated with greater neurological investigation or mortality. Length of stay was longer in children who received slow correction (<0.5 mmol/L per hour).

CONCLUSIONS

Our study did not find any evidence that rapid sodium correction was associated with greater neurological investigation, cerebral edema, seizures, or mortality; however, slow correction was associated with a longer hospital length of stay.