The mammalian pyruvate dehydrogenase complex (PDHC) is a mitochondrial matrix enzyme complex (greater than 7 million Daltons) that catalyzes the oxidative decarboxylation of pyruvate to form acetyl CoA, nicotinamide adenine dinucleotide (the reduced form, NADH), and CO(2). This reaction constitutes the bridge between anaerobic and aerobic cerebral energy metabolism. PDHC enzyme activity and immunoreactivity are lost in selectively vulnerable neurons after cerebral ischemia and reperfusion. Evidence from experiments carried out in vitro suggests that reperfusion-dependent loss of activity is caused by oxidative protein modifications. Impaired enzyme activity may explain the reduced cerebral glucose and oxygen consumption that occurs after cerebral ischemia. This hypothesis is supported by the hyperoxidation of mitochondrial electron transport chain components and NAD(H) that occurs during reperfusion, indicating that NADH production, rather than utilization, is rate limiting. Additional support comes from the findings that immediate postischemic administration of acetyl-L-carnitine both reduces brain lactate/pyruvate ratios and improves neurologic outcome after cardiac arrest in animals. As acetyl-L-carnitine is converted to acetyl CoA, the product of the PDHC reaction, it follows that impaired production of NADH is due to reduced activity of either PDHC or one or more steps in glycolysis. Impaired cerebral energy metabolism and PDHC activity are associated also with neurodegenerative disorders including Alzheimer's disease and Wernicke-Korsakoff syndrome, suggesting that this enzyme is an important link in the pathophysiology of both acute brain injury and chronic neurodegeneration.(c) 2004 Wiley-Liss, Inc.

Increased blood lactate concentration (hyperlactatemia) and lactic acidosis (hyperlactatemia and serum pH < 7.35) are common in patients with severe sepsis or septic shock and are associated with significant morbidity and mortality. In some patients, most of the lactate that is produced in shock states is due to inadequate oxygen delivery resulting in tissue hypoxia and causing anaerobic glycolysis. However, lactate formation during sepsis is not entirely related to tissue hypoxia or reversible by increasing oxygen delivery. In this review, we initially outline the metabolism of lactate and etiology of lactic acidosis; we then address the pathophysiology of lactic acidosis in sepsis. We discuss the clinical implications of serum lactate measurement in diagnosis, monitoring, and prognostication in acute and intensive care settings. Finally, we explore treatment of lactic acidosis and its impact on clinical outcome. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

Pyruvate dehydrogenase (PDH) is regulated both by covalent modification and through modulation of the active enzyme by metabolites. In the isolated heart, post-ischaemic inhibition of PDH, leading to uncoupling of glycolysis and glucose oxidation and a decrease in cardiac efficiency, has been described. In vivo, post-ischaemic reperfusion leads to metabolic abnormalities consistent with PDH inhibition, but the effects of ischaemia/reperfusion on PDH are not well characterized. We therefore investigated PDH regulation following transient ischaemia in vivo. In 33 open-chest dogs, the left anterior descending (LAD) was occluded for 20 min followed by 4 h reperfusion. In 17 dogs, dichloroacetate (DCA) was injected prior to reperfusion, while 16 dogs served as controls. In dogs without DCA, glucose oxidation and lactate uptake were lower in reperfused than in remote tissue, suggesting reduced flux through PDH. However, percent active and total PDH measured in myocardial biopsies were similar in both territories, excluding covalent enzyme modification or loss of functional enzyme. DCA activated PDH activity similarly in both regions and abolished differences in glucose oxidation and lactate uptake. Thus, decreased PDH flux in reperfused myocardium does not result from covalent modification or loss of total enzyme activity, but more likely from metabolite inhibition of the active enzyme. DCA leads to essentially complete activation of PDH, increases overall glucose utilization and abolishes post-ischaemic inhibition of glucose oxidation.

This 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations for advanced life support includes updates on multiple advanced life support topics addressed with 3 different types of reviews. Topics were prioritized on the basis of both recent interest within the resuscitation community and the amount of new evidence available since any previous review. Systematic reviews addressed higher-priority topics, and included double-sequential defibrillation, intravenous versus intraosseous route for drug administration during cardiac arrest, point-of-care echocardiography for intra-arrest prognostication, cardiac arrest caused by pulmonary embolism, postresuscitation oxygenation and ventilation, prophylactic antibiotics after resuscitation, postresuscitation seizure prophylaxis and treatment, and neuroprognostication. New or updated treatment recommendations on these topics are presented. Scoping reviews were conducted for anticipatory charging and monitoring of physiological parameters during cardiopulmonary resuscitation. Topics for which systematic reviews and new Consensuses on Science With Treatment Recommendations were completed since 2015 are also summarized here. All remaining topics reviewed were addressed with evidence updates to identify any new evidence and to help determine which topics should be the highest priority for systematic reviews in the next 1 to 2 years.Copyright © 2020. Published by Elsevier B.V.

The Declaration of Helsinki (DoH), adopted by the World Medical Association (WMA), is one of the most influential international documents in research ethics, is turning 50 in 2014. Its regular updates, seven versions (1975, 1983, 1989, 1996, 2000, 2008, 2013) and two notes of clarification (2002, 2004), characterize it as a 'live' document. The seventh version of the DoH was amended by the 64th WMA General Assembly, Fortaleza, Brazil, October 2013. The new version was reorganized and restructured, with paragraphs subdivided and regrouped. However, the DoH remains controversial and some ethical issues are still uncovered. The major problem was the insertion of the phrase 'less effective than the best proven' on placebo paragraph in order to allow double standard in medical research in low-resource countries. The DoH is a 'live' document, which will continually have to deal with new topics and challenges. Health equity needs to be a priority, and with that, a single ethical standard for medical research. Copyright © 2014 IMSS. Published by Elsevier Inc. All rights reserved.

Sepsis is a major health care problem, which affects millions of people around the world. Glucose metabolic reprogramming of immune cells plays a crucial role during advancement of sepsis. However, the association between glucose metabolic reprogramming and mortality in patients with sepsis is unclear. Lactate dehydrogenase (LDH) catalyzes the last step of glycolysis. Investigating the relationship between LDH and mortality is important to understand the effect of metabolic reprogramming on prognosis of patients with sepsis.A total of 192 patients with sepsis were included in our study. Data on characteristics of patients, biochemical variables, and inflammatory mediator were collected. Association between the level of serum LDH and 28-day mortality was also analyzed. The correlations between serum LDH, interleukin-1β, creatinine, PaO/FiO, and lactate were also observed. The association between LDH and the risk of death was further analyzed. Moreover, receiver operating characteristic curve was depicted to compare the accuracy in prediction of LDH and other variables.There were statistic difference in 28-day mortality between elevated LDH group and normal LDH group (P = 0.021). Level of serum LDH was an independent risk factor for death of patients with sepsis (hazard ratio 1.005, 95% confidence interval 1.002-1.007, P = 0.001). There were significant correlations between LDH, interleukin-1β (r = 0.514, P = 0.000), creatinine (r = 0.368, P = 0.000), PaO/FiO (r = -0.304, P = 0.000), and lactate (r = 0.560, P = 0.000). The receiver operating characteristic curves showed that the area under the LDH curve for prediction for mortality was 0.783.Serum LDH is probably associated with 28-day mortality in patients with sepsis.Copyright © 2018 Elsevier Inc. All rights reserved.

Guidance on post-cardiac arrest prognostication is largely based on data from out-of-hospital cardiac arrest (OHCA), despite clear differences between the OHCA and in-hospital cardiac arrest (IHCA) populations. Early prediction of mortality after IHCA would be useful to help make decisions about post-arrest care. We evaluated the ability of lactate and need for vasopressors after IHCA to predict hospital mortality.Single center retrospective observational study of adult IHCA patients who achieved sustained return of spontaneous circulation (ROSC), required mechanical ventilation peri-arrest and had a lactate checked within 2 h after ROSC. We evaluated the association of post-ROSC lactate and need for vasopressors with mortality using multivariate logistic regression.A total of 364 patients were included. Patients who received vasopressors within 3 h after ROSC had significantly higher mortality compared to patients who did not receive vasopressors (58% vs. 43%, p = 0.03). Elevated lactate level was associated with mortality (44% if lactate <5 mmol/L, 58% if lactate 5-10 mmol/L, and 73% if lactate >10 mmol/L, p < 0.01). A multivariable model with lactate group and post-ROSC vasopressor use as predictors demonstrated moderate discrimination (AUC 0.64 [95%CI:0.59-0.70]). Including other variables, the most parsimonious model included lactate, age, body mass index, race, and history of arrhythmia, cancer and/or liver disease (AUC 0.70 [95% CI: 0.64-0.75]).Post-ROSC lactate and need for vasopressors may be helpful in stratifying mortality risk in patients requiring mechanical ventilation after IHCA.Copyright © 2020 Elsevier B.V. All rights reserved.

Anaphase-promoting complex (APC) with its coactivator Cdh1 is required to maintain the postmitotic state of neurons via degradation of Cyclin B1, which aims to prevent aberrant cell cycle entry that causes neuronal apoptosis. Interestingly, evidence is accumulating that apart from the cell cycle, APC-Cdh1 also involves in neuronal metabolism via modulating the glycolysis promoting enzyme, 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-3 (PFKFB3). Here, we showed that under oxygen-glucose deprivation and reperfusion (OGD/R), APC-Cdh1 was decreased in primary cortical neurons. Likewise, the neurons exhibited enhanced glycolysis when oxygen supply was reestablished during reperfusion, which was termed as the "neuronal Warburg effect." In particular, the reperfused neurons showed elevated PFKFB3 expression in addition to a reduction in glucose 6-phosphate dehydrogenase (G6PD). Such changes directed neuronal glucose metabolism from pentose-phosphate pathway (PPP) to aerobic glycolysis compared to the normal neurons, resulting in increased ROS production and apoptosis during reperfusion. Pretreatment of neurons with Cdh1 expressing lentivirus before OGD could reverse this metabolic shift and attenuated ROS-induced apoptosis. However, the metabolism regulation and neuroprotection by Cdh1 under OGD/R condition could be blocked when co-transfecting neurons with Ken box-mut-PFKFB3 (which is APC-Cdh1 insensitive). Based on these data, we suggest that the Warburg effect may contribute to apoptotic mechanisms in neurons under OGD/R insult, and targeting Cdh1 may be a potential therapeutic strategy as both glucose metabolic regulator and apoptosis suppressor of neurons in brain injuries.

Aerobic glycolysis occurs during brain activation and is characterized by preferential up-regulation of glucose utilization compared with oxygen consumption even though oxygen level and delivery are adequate. Aerobic glycolysis is a widespread phenomenon that underlies energetics of diverse brain activities, such as alerting, sensory processing, cognition, memory, and pathophysiological conditions, but specific cellular functions fulfilled by aerobic glycolysis are poorly understood. Evaluation of evidence derived from different disciplines reveals that aerobic glycolysis is a complex, regulated phenomenon that is prevented by propranolol, a non-specific β-adrenoceptor antagonist. The metabolic pathways that contribute to excess utilization of glucose compared with oxygen include glycolysis, the pentose phosphate shunt pathway, the malate-aspartate shuttle, and astrocytic glycogen turnover. Increased lactate production by unidentified cells, and lactate dispersal from activated cells and lactate release from the brain, both facilitated by astrocytes, are major factors underlying aerobic glycolysis in subjects with low blood lactate levels. Astrocyte-neuron lactate shuttling with local oxidation is minor. Blockade of aerobic glycolysis by propranolol implicates adrenergic regulatory processes including adrenal release of epinephrine, signaling to brain via the vagus nerve, and increased norepinephrine release from the locus coeruleus. Norepinephrine has a powerful influence on astrocytic metabolism and glycogen turnover that can stimulate carbohydrate utilization more than oxygen consumption, whereas β-receptor blockade 're-balances' the stoichiometry of oxygen-glucose or -carbohydrate metabolism by suppressing glucose and glycogen utilization more than oxygen consumption. This conceptual framework may be helpful for design of future studies to elucidate functional roles of preferential non-oxidative glucose utilization and glycogen turnover during brain activation. Aerobic glycolysis, the preferential up-regulation of glucose utilization (CMRglc ) compared with oxygen consumption (CMRO2 ) during brain activation, is blocked by propranolol. Epinephrine release from the adrenal gland stimulates vagus nerve signaling to the locus coeruleus, enhancing norepinephrine release in the brain, and regulation of astrocytic and neuronal metabolism to stimulate CMRglc more than CMRO2. Propranolol suppresses CMRglc more than CMRO2.© 2016 International Society for Neurochemistry.

Mitochondrial dysfunction is a hallmark of almost all diseases. Acquired or inherited mutations of the mitochondrial genome DNA may give rise to mitochondrial diseases. Another class of disorders, in which mitochondrial impairments are initiated by extramitochondrial factors, includes neurodegenerative diseases and syndromes resulting from typical pathological processes, such as hypoxia/ischemia, inflammation, intoxications, and carcinogenesis. Both classes of diseases lead to cellular energetic depression (CED), which is characterized by decreased cytosolic phosphorylation potential that suppresses the cell's ability to do work and control the intracellular Ca(2+) homeostasis and its redox state. If progressing, CED leads to cell death, whose type is linked to the functional status of the mitochondria. In the case of limited deterioration, when some amounts of ATP can still be generated due to oxidative phosphorylation (OXPHOS), mitochondria launch the apoptotic cell death program by release of cytochrome c. Following pronounced CED, cytoplasmic ATP levels fall below the thresholds required for processing the ATP-dependent apoptotic cascade and the cell dies from necrosis. Both types of death can be grouped together as a mitochondrial cell death (MCD). However, there exist multiple adaptive reactions aimed at protecting cells against CED. In this context, a metabolic shift characterized by suppression of OXPHOS combined with activation of aerobic glycolysis as the main pathway for ATP synthesis (Warburg effect) is of central importance. Whereas this type of adaptation is sufficiently effective to avoid CED and to control the cellular redox state, thereby ensuring the cell survival, it also favors the avoidance of apoptotic cell death. This scenario may underlie uncontrolled cellular proliferation and growth, eventually resulting in carcinogenesis.

Synaptic activity drives changes in gene expression to promote long lasting adaptations of neuronal structure and function. One example of such an adaptive response is the buildup of acquired neuroprotection, a synaptic activity- and gene transcription-mediated increase in the resistance of neurons against harmful conditions. A hallmark of acquired neuroprotection is the stabilization of mitochondrial structure and function. We therefore re-examined previously identified sets of synaptic activity-regulated genes to identify genes that are directly linked to mitochondrial function. In mouse and rat primary hippocampal cultures, synaptic activity caused an up-regulation of glycolytic genes and a concomitant down-regulation of genes required for oxidative phosphorylation, mitochondrial biogenesis, and maintenance. Changes in metabolic gene expression were induced by action potential bursting, but not by glutamate bath application activating extrasynaptic NMDA receptors. The specific and coordinate pattern of gene expression changes suggested that synaptic activity promotes a shift of neuronal energy metabolism from oxidative phosphorylation toward aerobic glycolysis, also known as the Warburg effect. The ability of neurons to up-regulate glycolysis has, however, been debated. We therefore used FACS sorting to show that, in mixed neuron glia co-cultures, activity-dependent regulation of metabolic gene expression occurred in neurons. Changes in gene expression were accompanied by changes in the phosphorylation-dependent regulation of the key metabolic enzyme, pyruvate dehydrogenase. Finally, increased synaptic activity caused an increase in the ratio of l-lactate production to oxygen consumption in primary hippocampal cultures. Based on these data we suggest the existence of a synaptic activity-mediated neuronal Warburg effect that may promote mitochondrial homeostasis and neuroprotection.© 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Hyperlactatemia may occur for a variety of reasons and is a predictor of poor clinical outcome. However, only limited data are available on the underlying causes of hyperlactatemia and the mortality rates associated with severe hyperlactatemia in critically ill patients. We therefore aimed to evaluate the etiology of severe hyperlactatemia (defined as a lactate level >10 mmol/L) in a large cohort of unselected ICU patients. We also aimed to evaluate the association between severe hyperlactatemia and lactate clearance with ICU mortality.In this retrospective, observational study at an University hospital department with 11 ICUs during the study period between 1 April 2011 and 28 February 2013, we screened 14,040 ICU patients for severe hyperlactatemia (lactate >10 mmol/L).Overall mortality in the 14,040 ICU patients was 9.8 %. Of these, 400 patients had severe hyperlactatemia and ICU mortality in this group was 78.2 %. Hyperlactatemia was associated with death in the ICU [odds ratio 1.35 (95 % CI 1.23; 1.49; p < 0.001)]. The main etiology for severe hyperlactatemia was sepsis (34.0 %), followed by cardiogenic shock (19.3 %), and cardiopulmonary resuscitation (13.8 %). Patients developing severe hyperlactatemia >24 h of ICU treatment had a significantly higher ICU mortality (89.1 %, 155 of 174 patients) than patients developing severe hyperlactatemia ≤ 24 h of ICU treatment (69.9 %, 158 of 226 patients; p < 0.0001). Lactate clearance after 12 h showed a receiver-operating-characteristics area under the curve (ROC-AUC) value of 0.91 to predict ICU mortality (cut-off showing highest sensitivity and specifity was a 12 h lactate clearance of 32.8 %, Youden Index 0.72). In 268 patients having a 12-h lactate clearance <32.8 % ICU mortality was 96.6 %.Severe hyperlactatemia (>10 mmol/L) is associated with extremely high ICU mortality especially when there is no marked lactate clearance within 12 h. In such situations, the benefit of continued ICU therapy should be evaluated.

To predict 28-day mortality with serum lactate and oxygenation profile in sepsis.82 patients were admitted to the ICU with sepsis. Comorbid disease, hemodynamic and oxygenation parameters were recorded. Serum lactate was measured at T0, T6, T12 and T24 hours of admission. Arterial and venous oxygen saturation levels were also measured. Regression and ROC analyses were used to predict death within 28days.Out of 82 patients, 32 died within 28days of ICU admission. Non-survivors differed from survivors in having higher serum lactate concentrations on admission (0.6mmol/L; P=0.033), requiring more norepinephrine (14μg/min; P<0.001), higher frequency of acute kidney injury, prolonged mechanical ventilation (5-days; P<0.001) and ICU stay (1-day; P=0.029). Saturation of oxygen in arterial (a), central venous blood (cv) and (a-cv) were similar between the survivors and non-survivors. T24 level of lactate was the best predictor of 28-day mortality with 78% sensitivity and 90% specificity (AUC=0.912±0.033).Serial measurements of serum lactate with special emphasis on its concentration at 24hour after admission remains the most predictive of short-term mortality in the ICU. Other predictors of mortality are relatively inferior and must be used collectively in context to better predict the clinical outcome of sepsis.Published by Elsevier Inc.

Trauma patients require early assessment of injury severity. Trauma scores, although well validated, can be unwieldy in the emergency clinical setting. We sought to evaluate the prognostic value of initial serum lactate (ISL) for mortality, operative intervention (OI), and intensive care unit admission (ICUA) in trauma patients. We conducted an institutional review board-approved retrospective study. We reviewed all trauma patients between January 2007 and June 2012 in our prospectively maintained database. We included only adults whose ISL had been drawn within the first 35 min after arrival. We included only those patients whose interval between injury and arrival was within 24 h. Survivors and nonsurvivors were compared using logistic regression, Mann-Whitney U, and chi-square tests. Discriminating ability of ISL for mortality was assessed with receiver operating characteristic analysis. Our secondary outcomes (ICUA and OI) were evaluated with logistic regression test and receiver operating characteristic analysis. A total of 1,941 patients were included. Overall mortality was 6.2%. Median ISL was 32 mg/dL (interquartile range, 17 - 62) for nonsurvivors versus 21 mg/dL (interquartile range, 14 - 32) for survivors (P < 0.001). In multivariate analysis, ISL was a significant covariate for mortality (P = 0.015). The odds ratio was 1.010 (95% confidence interval, 1.002 - 1.019). The area under the curve was 0.63. The ISL was a significant covariate for OI (P = 0.033). The ISL did not reach significance for ICUA. The ISL is an easily measured, rapid, and inexpensive test that can help to quickly stratify injury severity in trauma patients. We have found that ISL, when used in strictly selected patients, can predict OI and mortality.

We aimed to investigate the association between serum lactate levels during cardiopulmonary resuscitation (CPR) and survival in patients with out-of-hospital cardiac arrest (OHCA). From the database of a multicenter registry on OHCA patients, we included adult nontraumatic OHCA patients transported to the hospital with ongoing CPR. Based on the serum lactate levels during CPR, the patients were divided into four quartiles: Q1 (≤ 10.6 mEq/L), Q2 (10.6-14.1 mEq/L), Q3 (14.1-18.0 mEq/L), and Q4 (> 18.0 mEq/L). The primary outcome was 1-month survival. Among 5226 eligible patients, the Q1 group had the highest 1-month survival (5.6% [74/1311]), followed by Q2 (3.6% [47/1316]), Q3 (1.7% [22/1292]), and Q4 (1.0% [13/1307]) groups. In the multivariable logistic regression analysis, the adjusted odds ratio of Q4 compared with Q1 for 1-month survival was 0.24 (95% CI 0.13-0.46). 1-month survival decreased in a stepwise manner as the quartiles increased (p for trend < 0.001). In subgroup analysis, there was an interaction between initial rhythm and survival (p for interaction < 0.001); 1-month survival of patients with a non-shockable rhythm decreased when the lactate levels increased (p for trend < 0.001), but not in patients with a shockable rhythm (p for trend = 0.72). In conclusion, high serum lactate level during CPR was associated with poor 1-month survival in OHCA patients, especially in patients with non-shockable rhythm.

We analysed the relationship between serum levels of lactate within 1h of return of spontaneous circulation (ROSC) and survival and neurological outcomes in patients who underwent therapeutic hypothermia (TH).This was a multi-centre retrospective and observational study that examined data from the first Korean Hypothermia Network (KORHN) registry from 2007 to 2012. The inclusion criteria were out-of-hospital cardiac arrest (OHCA) and examination of serum levels of lactate within 1h after ROSC, taken from KORHN registry data. The primary endpoint was survival outcome at hospital discharge, and the secondary endpoint was poor neurological outcome (Cerebral Performance Category, CPC, 3-5) at hospital discharge. Initial lactate levels and other variables collected within 1h of ROSC were analysed via multivariable logistic regression.Data from 930 cardiac arrest patients who underwent TH were collected from the KORHN registry. In a total of 443 patients, serum levels of lactate were examined within 1h of ROSC. In-hospital mortality was 289/443 (65.24%), and 347/443 (78.33%) of the patients had CPCs of 3-5 upon hospital discharge. The odds ratios of lactate levels for CPC and in-hospital mortality were 1.072 (95% confidence interval (CI) 1.026-1.121) and 1.087 (95% CI=1.031-1.147), respectively, based on multivariate ordinal logistic regression analyses.High levels of lactate in serum measured within 1h of ROSC are associated with hospital mortality and high CPC scores in cardiac arrest patients treated with TH.Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Recent studies have suggested that serum lactate may serve as a marker to predict mortality after resuscitation from cardiac arrest (CA). The relationship between serum lactate and CA outcomes requires further characterization, especially among patients treated with therapeutic hypothermia (TH) and aggressive post-arrest care.A retrospective analysis of patients resuscitated from non-traumatic CA at three urban U.S. hospitals was performed using an established internet-based post-arrest registry. Adult (≥ 18 years) patients resuscitated from CA and receiving TH treatment were included. Logistic regression analysis was used to adjust for potential confounders to survival outcomes. Survival to discharge served as the primary endpoint.A total of 199 post-CA patients treated with TH between 5/2005 and 11/2011 were included in this analysis. The mean age was 56.9 ± 16.5 years, 85/199 (42.7%) patients were female, and survival to discharge was attained in 84/199 (42.2%). While lower initial post-CA serum lactate levels were not associated with increased survival to discharge, subsequent lactate measurements were significantly associated with outcomes (24-h serum lactate levels in survivors vs. non-survivors, 2.7 ± 0.5 vs. 4.2 ± 0.4 mmol/L, p<0.01). Multivariable logistic regression confirmed this relationship with survival to discharge (p<0.01).Lower serum lactate levels at 12h and 24h, but not initially following cardiac arrest, are associated with survival to hospital discharge after resuscitation from CA and TH treatment. Prospective investigation of serum lactate as a potential prognostic tool in CA is needed.Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Early post-traumatic seizures (EPTS) refer to epileptic seizures occurring within one week after brain injury. This study aimed to define the risk factors of EPTS and the protective factors that could prevent its occurrence.This is a single-center retrospective study in the PICU, Beijing Children's Hospital. Patients diagnosed with traumatic brain injury (TBI), admitted with and without EPTS between January 2016 and December 2020 were included in the study.We included 108 patients diagnosed with TBI. The overall EPTS incidence was 33.98% (35/108). The correlation between EPTS and depressed fractures is positive (P = 0.023). Positive correlations between EPTS and intracranial hemorrhage and subarachnoid hemorrhage had been established (P = 0.011and P = 0.004, respectively). The detection rates of EPTS in the electroencephalogram (EEG) monitoring was 80.00%. There was a significant difference in the EEG monitoring rate between the two groups (P = 0.041). Forty-one (37.86%, 41/108) post-neurosurgical patients were treated with prophylactic antiepileptic drugs (AEDs), and eight (19.51%, 8/41) still had seizures. No statistical significance was noted between the two groups in terms of prophylactic AEDs use (P = 0.519). Logistic regression analysis revealed that open craniocerebral injury and fever on admission were risk factors for EPTS, whereas, surgical intervention and use of hypertonic saline were associated with not developing EPTS.Breakthrough EPTS occurred after severe TBI in 33.98% of pediatric cases in our cohort. This is a higher seizure incidence than that reported previously. Patients with fever on admission and open craniocerebral injuries are more likely to develop EPTS.© 2022. Children's Hospital, Zhejiang University School of Medicine.

In clinical practice, monitoring of the efficacy of resuscitation can be challenging. The prediction of cerebral and overall outcome in particular is an unmet medical need. Microdialysis is a minimally invasive technique for the continuous determination of metabolic parameters in vivo. Using this technique, we set out to establish a model allowing for concomitant determination of cerebral and peripheral metabolism in a cardiac arrest setting in rodents.Microdialysis settings were optimized in vitro and then used in male Sprague-Dawley rats. Probes were implanted into the CA1 region of the right hippocampus and the right femoral vein. With a time interval of 8 min, glucose, lactate, pyruvate, and glutamate levels were determined during baseline conditions, untreated ventricular fibrillation cardiac arrest, cardiopulmonary resuscitation (CPR), reperfusion, and death.In 16 rodents, restoration of spontaneous circulation was achieved in seven animals. Characteristic metabolic changes were evident during cardiac arrest and reperfusion with both probes. Ischemic patterns in peripheral compartments were delayed and more variable compared to the changes in cerebral metabolism highlighting the importance of cerebral metabolic monitoring. Microdialysis allowed distinguishing between survivors and non-survivors 8 min after termination of CPR. Cerebral glutamate showed a trend toward higher levels in non-survivors during CPR.We established a new rodent model for research in hypoxic ischemic encephalopathy. This setting allows to investigate the impact of resuscitation methods on cerebral and peripheral metabolism simultaneously. The present model may be used to evaluate different resuscitation strategies in order to optimize brain survival in future studies.

Bedside detection and early treatment of lasting cerebral ischemia may improve outcome after out-of-hospital cardiac arrest (OHCA). This feasibility study explores the possibilities to use microdialysis (MD) for continuous monitoring of cerebral energy metabolism by analyzing the draining cerebral venous blood. Eighteen comatose patients were continuously monitored with jugular bulb and radial artery (reference) MD following resuscitation. Median time from cardiac arrest to MD was 300 min (IQR 230-390) with median monitoring time 60 h (IQR 40-81). The lactate/pyruvate ratio in cerebral venous blood was increased during the first 20 h after OHCA, and significant differences in time-averaged mean MD metabolites between jugular venous and artery measurements, were documented (p < 0.02). In patients with unfavorable outcome (72%), cerebral venous lactate and pyruvate levels remained elevated during the study period. In conclusion, the study indicates that jugular bulb microdialysis (JBM) is feasible and safe. Biochemical signs of lasting ischemia and mitochondrial dysfunction are frequent and associated with unfavorable outcome. The technique may be used in comatose OHCA patients to monitor biochemical variables reflecting ongoing brain damage and support individualized treatment early after resuscitation.© 2021. The Author(s).

Blood lactate elevation in critically ill patients commonly is taken as a sign of impaired tissue perfusion. Simultaneous elevation of lactate to pyruvate ratio (L/P ratio) may be helpful in discriminating between different mechanisms of hyperlactatemia and thus in determining the relevance of the finding. We studied prospectively the prevalence and the time pattern of hyperlactatemia and simultaneous L/P ratio elevation in 98 consecutive emergency admission patients in a 23-bed surgical-medical University Hospital intensive care unit. Blood lactate, L/P ratio, and blood gases were measured at 2-h intervals during the initial 24 h of intensive care unit admission. Hyperlactatemia (blood lactate over 2 mmol/L) was found in 48 (49%) patients, and the median peak value of the non-survivors was higher than that of the survivors [5.3 (interquartile range 1.9-7.5) vs. 1.9 (1.3-2.9) mmol/L, respectively, p = 0.003]. Hyperlactatemia at admission (n = 31) was associated with a higher hospital mortality than hyperlactatemia developing later (n = 17) (29.0% vs. 5.9%, P = 0.003). Sustained admission hyperlactatemia (>6 h) was associated with higher mortality than short-lasting hyperlactatemia (36.8% vs. 0%, P = 0.008). Simultaneously elevated L/P ratio (L/P ratio > 18; n = 16) was associated with higher mortality than hyperlactatemia with normal L/P ratio (n = 32; 37.5% vs. 12.5%, respectively, P = 0.03) and was found mainly in patients who had severe circulatory failure. The hyperlactatemia of patients with sepsis was not associated with L/P ratio elevation. We conclude that hyperlactatemia is common in emergency admission patients. Hyperlactatemia with L/P ratio elevation and lactic acidosis is likely to be associated with inadequate tissue perfusion. Hyperlactatemia persisting more than 6 h and simultaneous elevation of L/P ratio are associated with increased mortality.

Emerging evidence indicates that there is a complex interplay between metabolism and chronic disorders in the nervous system. In particular, the pyruvate dehydrogenase (PDH) kinase (PDK)-lactic acid axis is a critical link that connects metabolic reprogramming and the pathophysiology of neurological disorders. PDKs, via regulation of PDH complex activity, orchestrate the conversion of pyruvate either aerobically to acetyl-CoA, or anaerobically to lactate. The kinases are also involved in neurometabolic dysregulation under pathological conditions. Lactate, an energy substrate for neurons, is also a recently acknowledged signaling molecule involved in neuronal plasticity, neuron-glia interactions, neuroimmune communication, and nociception. More recently, the PDK-lactic acid axis has been recognized to modulate neuronal and glial phenotypes and activities, contributing to the pathophysiologies of diverse neurological disorders. This review covers the recent advances that implicate the PDK-lactic acid axis as a novel linker of metabolism and diverse neuropathophysiologies. We finally explore the possibilities of employing the PDK-lactic acid axis and its downstream mediators as putative future therapeutic strategies aimed at prevention or treatment of neurological disorders.Copyright © 2016 Elsevier Ltd. All rights reserved.

Coronavirus disease 2019 (COVID-19) infection has now reached a pandemic state, affecting more than a million patients worldwide. Predictors of disease outcomes in these patients need to be urgently assessed to decrease morbidity and societal burden. Lactate dehydrogenase (LDH) has been associated with worse outcomes in patients with viral infections. In this pooled analysis of 9 published studies (n = 1532 COVID-19 patients), we evaluated the association between elevated LDH levels measured at earliest time point in hospitalization and disease outcomes in patients with COVID-19. Elevated LDH levels were associated with a ~6-fold increase in odds of developing severe disease and a ~16-fold increase in odds of mortality in patients with COVID-19. Larger studies are needed to confirm these findings.Copyright © 2020 Elsevier Inc. All rights reserved.