The spectrum of sepsis-associated encephalopathy: a clinical perspective

pH-triggered small molecule nanodrugs self-assembled from tryptamine-cinnamaldehyde and fisetin for targeted sepsis-associated encephalopathy therapy

Sepsis-associated encephalopathy (SAE) is an acute diffuse brain dysfunction, but its clinical treatment just focuses on antibiotics and supportive therapy, which fail to directly limit the development of SAE. Herein, this work highlights the development of pH-triggered small molecule nanodrugs self-assembled from tryptamine (Try)-cinnamaldehyde (CA) and fisetin for targeted SAE therapy. The imine linkage in Try-CA and acid-dependent protonation of Try and fisetin endow the nanodrugs with pH-triggered dynamic changes of particle sizes, surficial charges, and drug release. Moreover, the combined use of Try-CA and fisetin also endows the nanodrugs with superior antioxidative, anti-inflammatory and antibacterial capabilities compared to their individual use. These characteristics of the nanodrugs facilitate long-term circulation stability, effective penetration through BBB, selective accumulation in the brain, and target to central and peripheral focal areas, thereby achieving comprehensive treatment or relief of SAE. Thus, these attractive experimental results illuminate the enormous potential of such pH-triggered small molecule nanodrugs for targeted SAE therapy, advancing their use in clinics.

Triglyceride-glucose index: a novel prognostic marker for sepsis-associated encephalopathy severity and outcomes

Background

Sepsis-associated encephalopathy (SAE) is a complex condition with variable outcomes. This study investigates the potential of the Triglyceride-glucose (TyG) index as a marker for disease severity and prognosis in SAE patients.

Methods

We conducted a retrospective cohort study using data from the Medical Information Mart for Intensive Care (MIMIC-IV) database. Patients with sepsis who were admitted to the intensive care unit (ICU) were categorized into two groups based on the occurrence of SAE. Key clinical outcomes were 90-day survival (primary outcome) and length of ICU and hospital stays, as well as the use of vasoactive medications (secondary outcomes). The TyG index was calculated, and its association with disease severity scores and patient outcomes was analyzed using statistical methods, including survival analysis, Cox regression, and correlation analyses.

Results

The study population's median age was 65.96 years, predominantly male (60.1%). Higher TyG index scores correlated with elevated clinical severity scores (APSIII, LODS, OASIS, SAPSII, and CCI) and increased ICU and hospital stay durations. TyG index categorization revealed significant differences in 90-day survival probabilities, with "high TyG" associated with a 25% increased mortality risk compared to "low TyG." Furthermore, TyG index showed a moderate positive correlation with ICU stay duration and use of norepinephrine and vasopressin, but not with dopamine and epinephrine use.

Conclusion

The TyG index is a significant independent predictor of disease severity and prognosis in SAE patients. High TyG levels correlate with worse clinical outcomes and increased mortality risk, suggesting its potential as a valuable tool in managing SAE.

Optimized Mouse Model of Sepsis-Associated Encephalopathy: A Rational Standard Based on Modified SHIRPA Score and Neurobehaviors in Mice

BACKGROUND

Sepsis-associated encephalopathy (SAE), a severe neurological disorder, is marked by widespread brain dysfunction. At present, there is no universally accepted criterion for diagnosing SAE in animal models. This study proposes a standardized evaluation method for SAE in mice, addressing inconsistencies in current research.

METHOD

Using a cecal ligation and puncture (CLP) model to induce sepsis, we assessed the physiological status of mice with a modified SHIRPA score to differentiate SAE from non-SAE, validating our findings through various behavioral tests and evaluations of neuroinflammation and neuronal damage.

RESULTS

Our findings revealed that the conventional mild-moderate-severe categorization of SHIRPA was insufficient for distinguishing between SAE and non-SAE. To enhance differentiation, we classified mice based on the median modified SHIRPA score, validating this approach through behavioral tests including the Y-maze, three-chamber social test, and open field test. This method effectively identified neurological impairments in septic mice. Further validation involved assessing neuronal damage, neuroinflammation, the Morris water maze, and long-term potentiation (LTP) in the hippocampal CA1 region. Results indicated that mice in the up-Median group exhibited greater neuroinflammation, neuronal injury, and cognitive deficits compared to the down-Median group.

CONCLUSIONS

This study establishes a reliable evaluation method for SAE in murine models, facilitating improved differentiation between SAE and non-SAE. Such advancements will enhance our understanding of the pathogenesis of SAE and guide more effective treatment strategies.

Alterations in Regional Brain Microcirculation in Patients with Sepsis: A Prospective Study Using Contrast-Enhanced Brain Ultrasound

BACKGROUND

Alterations in regional brain microcirculation have not been well studied in patients with sepsis. Regional brain microcirculation can be studied using contrast-enhanced brain ultrasound (CEUS) with microbubble administration.

METHODS

CEUS was used to assess alterations in regional brain microcirculation on 3 consecutive days in 58 patients with sepsis and within 24 h of intensive care unit admission in 10 aged-matched nonseptic postoperative patients. Time-intensity perfusion curve variables (time-to-peak and peak intensity) were measured in different regions of interest of the brain parenchyma. The mean arterial pressure, cardiac index (using transthoracic echocardiography), global cerebral blood flow (using echo-color Doppler of the carotid and vertebral arteries), mean flow velocities of the middle cerebral arteries, and brain autoregulation (using transcranial echo-color Doppler) were measured simultaneously. The presence of structural brain injury in patients with sepsis was confirmed on computed tomography imaging, and encephalopathy, including coma and delirium, was evaluated using the Glasgow Coma Scale and the Confusion Assessment Method in the Intensive Care Unit.

RESULTS

Of the 58 patients with sepsis, 42 (72%) developed acute encephalopathy and 11 (19%) had some form of structural brain injury. Brain autoregulation was impaired in 23 (40%) of the patients with sepsis. Brain microcirculation alterations were observed in the left lentiform nucleus and left white matter of the temporoparietal region of the middle cerebral artery in the sepsis nonsurvivors but not in the survivors or postoperative patients. The alterations were characterized by prolonged time-to-peak (p < 0.01) and decreased peak intensity (p < 0.01) on the time-intensity perfusion curve. Prolonged time-to-peak but not decreased peak intensity was independently associated with worse outcome (p = 0.03) but not with the development of encephalopathy (p = 0.77).

CONCLUSIONS

Alterations in regional brain microcirculation are present in critically ill patients with sepsis and are associated with poor outcome. Trial registration Registered retrospectively on December 19, 2019.

Immune Checkpoint VISTA Negatively Regulates Microglia Glycolysis and Activation via TRIM28-Mediated Ubiquitination of HK2 in Sepsis-Associated Encephalopathy

V-domain immunoglobulin suppressor of T cell activation (VISTA) has emerged as a crucial player in the pathogenesis of neurological disorders. However, the specific mechanism by which VISTA regulates microglial activation remains unclear. Septic mice were intracerebroventricularly injected with an agonistic anti-VISTA antibody or isotype control. To investigate the differential gene expression profiles, RNA sequencing was conducted on brain tissues from these mice. In vitro, VISTA was silenced in BV2 microglial cells using shRNA. Co-immunoprecipitation assays were performed to identify protein-protein interactions involving hexokinase 2 (HK2), and ubiquitination assays were used to examine the ubiquitination status of HK2. Additionally, BV2 cells were transfected with either tripartite motif-containing 28 overexpression plasmids (TRIM28-PcDNA3.1( +)) or TRIM28-specific siRNA to assess the impact of TRIM28 on VISTA-mediated microglial activation. The cellular glycolytic activity was measured using extracellular acidification rate assays, and proinflammatory cytokine and chemokines were quantified. Treatment with VISTA antibodies significantly alleviated microglial activation and prevented cognitive impairment in septic mice. In contrast, VISTA silencing in BV2 microglia led to the overexpression of proinflammatory cytokines and enhanced glycolysis in an HK2-dependent manner. Mechanistically, HK2 expression was regulated by the E3 ubiquitin ligase TRIM28 through K63-linked ubiquitination, which targeted HK2 for proteasomal degradation. Furthermore, knockdown of TRIM28 reduced the elevated glycolysis and proinflammatory response observed in VISTA-silenced microglia. VISTA modulates microglial activation in sepsis-associated encephalopathy by regulating HK2 expression through TRIM28-mediated K63-linked ubiquitination. These findings highlight VISTA as a potential therapeutic target for modulating microglial activation in sepsis.

Hexokinase 2 promotes ISGylation of Acyl-CoA synthetase long-chain family member 4 in sepsis-induced microglia cells

Metabolic reprogramming is often observed in sepsis-associated microglial cells. However, little is known about the aberrant metabolic genes involved in neuroinflammation and lipid accumulation in microglial cells of sepsis-associated encephalopathy (SAE). Here, we show that hexokinase 2 (HK2) is upregulated and strongly associated with the inflammatory response and lipid metabolism in lipopolysaccharide-induced BV2 cells. Downregulation of HK2 lowered the activation of NOD-like receptor signaling family pyrin domain containing 3, both in BV2 cells and in the hippocampus of cecal ligation and puncture-induced male septic mice. Moreover, the inhibition of HK2 promoted lipid droplet reduction. Mechanistically, HK2 knockdown in microglial cells reduced the ISGylation of Acyl-CoA Synthetase Long-chain Family Member 4 (ACSL4) by interferon-stimulated gene 15 (ISG15). Notably, siISG15 effectively down-regulated the expression of ACSL4 in lipopolysaccharide-induced BV2 cells. Our findings provide new mechanistic insights into HK2 in microglial cells through regulation of ACSL4 ISGylation, suggesting a promising therapeutic strategy for treating SAE by targeting HK2. Our findings suggest that HK2 modulates ISGylation of ACSL4 in sepsis-induced microglial cells, indicating that therapeutic targeting of HK2 may constitute a promising strategy for SAE.

Investigating the role of aspirin on the mortality risk of sepsis-associated encephalopathy: a retrospective study

Background

Sepsis-associated encephalopathy (SAE) is one of the most common complications of sepsis. Aspirin can serve as a promising therapeutic candidate and help improve patient outcomes in sepsis and its complications. However, the efficacy and safety of aspirin on SAE remains largely unexplored.

Methods

Patients for this retrospective study were collected from MIMIC-IV (version 3.0). Propensity score matching (PSM) was used to balance the baseline characteristics between the no aspirin group and aspirin group. The association between aspirin therapy and mortality risk of in-hospital, 30-day, 60-day, 90-day, and 180-day was analyzed by Cox proportional hazards model and Kaplan-Meier method. E-value analysis was used to evaluate the potential influence of unmeasured or unknown confounding factors. Subgroup analysis was applied to explore potential differences in the effects of aspirin therapy on clinical outcomes across these various groups.

Results

Our study recruited 4,707 SAE patients in total, and 2,518 patients were enrolled after PSM. The mortality rate for in-hospital, 30-day, 60-day, 90-day, and 180-day in the aspirin group was consistently significant lower than that in the no aspirin group. Kaplan-Meier curves revealed that the SAE patients received aspirin therapy exhibited a notably higher survival rate compared to those who did not. The risk of gastrointestinal hemorrhage had no significant difference between the two groups. Additionally, the mortality rate of SAE patients in aspirin pre-ICU group, aspirin in-ICU group, and aspirin pre-ICU and in-ICU group decreased significantly compared to the no aspirin group. The high-dose aspirin group experienced a significantly higher mortality rate compared to those in the low-dose group.

Conclusion

Aspirin could reduce the mortality risk of SAE patients for in-hospital, 30-day, 60-day, 90-day, and 180-day, without increasing the risk of gastrointestinal hemorrhage. The benefits observed persisted regardless of aspirin exposure timing. Patients received high-dose aspirin exhibited a higher mortality risk compared to those in the low-dose group.

Management of severe acute encephalopathy in the ICU: an expert consensus statement from the french society of intensive care medicine

INTRODUCTION

Acute encephalopathy in the ICU poses significant diagnostic, therapeutic, and prognostic challenges. Standardized expert guidelines on acute encephalopathy are needed to improve diagnostic methods, therapeutic decisions, and prognostication.

METHODS

The experts conducted a review of the literature, analysed it according to the GRADE (Grading of Recommendation, Assessment, Development and Evaluation) methodology and made proposals for guidelines, which were rated by other experts. Only expert opinions with strong agreement were selected.

RESULTS

The synthesis of expert work and the application of the GRADE method resulted in 39 recommendations. Among the 39 formalized recommendations, 1 had a high level of evidence (GRADE 1 +) and 10 had a low level of evidence (GRADE 2 + or 2-). These recommendations describe indication for ICU admission, use of clinical scores and EEG for diagnosis, detection of complications, and prognostication. The remaining 28 recommendations were based on expert consensus. These recomandations describe common indications for blood and CSF studies, neuroimaging, use of neuromonitoring, and provide guidelines for management in the acute phase.

CONCLUSION

This expert consensus statement aims to provide a structured framework to enhance the consistency and quality of care for ICU patients presenting with acute encephalopathy. By integrating high-quality evidence with expert opinion, it offers a pragmatic approach to addressing the complex nature of acute encephalopathy in the ICU, promoting best practices in patient care and facilitating future research in the field.

Identification and Evaluation of Lipocalin-2 in Sepsis-Associated Encephalopathy via Machine Learning Approaches

Purpose

Sepsis-associated encephalopathy (SAE) critically contributes to poor prognosis in septic patients. Identifying and screening key genes responsible for SAE, as well as exploring potential targeted therapies, are vital for improving the management of sepsis and advancing precision medicine.

Patients and Methods

Single-cell RNA sequencing (scRNA-seq) was administrated to identify cell subpopulations related to poor prognosis in septic patients. Next, hierarchical dynamic weighted gene co-expression network analysis (hdWGCNA) was employed to identify genes associated with specific neutrophil subpopulations. Enrichment analysis revealed the biological functions of these genes. Subsequently, neuroinflammation-related genes were obtained to construct a neuroinflammation-related signature. The AddModuleScore algorithm was used to calculate neuroinflammation scores for each cell subpopulation, whereas the CellCall algorithm was used to assess the crosstalk between neutrophils and other cell subpopulations. To identify key genes accurately, four binary classification machine learning algorithms were utilized. Finally, Western blotting and behavioral tests were used to confirm the role of LCN2-related neuroinflammation in septic mice.

Results

This study utilized scRNA-seq to reveal the critical role of peripheral neutrophils during sepsis, identifying these neutrophils as contributors to poor prognosis and associated with neuroinflammation. On the basis of various machine learning algorithms, we discovered that Lipocalin-2 (LCN2) may be the key gene involved in neutrophil-induced SAE. To prove these findings, we conducted in vivo experiments and an animal model. Increased LCN2 expression and cognitive dysfunction occurred in septic mice. Additionally, the levels of markers of astrocytes and microglia and inflammatory factors such as TNF-α and IL-6 were significantly increased. All these phenomena were reversed by the downregulation of LCN2.

Conclusion

The upregulation of LCN2 expression on peripheral neutrophils is a critical step that triggers neuroinflammation in the central nervous system during SAE.

Molecular mechanism of METTL3 regulating hippocampal neuronal injury induced by sepsis-associated encephalopathy

OBJECTIVE

This study explores the mechanism of methyltransferase like 3 (METTL3) on sepsis-associated encephalopathy (SAE)-induced hippocampal neuronal injury.

METHODS

A murine model of SAE was established by caecal ligation and puncture. Hippocampal cells were induced by lipopolysaccharide (LPS). The mouse survival was observed and behavioural tests evaluated cognitive function. METTL3 and glutamic-oxaloacetic transaminase 1 (GOT1) expressions were detected via RT-qPCR and Western blot. Immunofluorescence staining examined the co-localization of NeuN and METTL3. The m6A enrichment on GOT1 was determined by MeRIP.

RESULTS

METTL3 and GOT1 were highly expressed in SAE mice and LPS-stimulated hippocampal cells. SAE mice exhibited cognitive function impairment, reduced survival rate, and decreased neuronal cells. LPS induction increased hippocampal cell apoptosis and enhanced inflammation. Silence of METTL3 reduced hippocampal neuronal injury in SAE mice and LPS-induced hippocampal cell injury.

CONCLUSION

METTL3-mediated m6A modification on GOT1 mRNA elevates GOT1 expression, thereby aggravating SAE-induced hippocampal neuronal injury.

LCN2 induces neuronal loss and facilitates sepsis-associated cognitive impairments

Sepsis-associated encephalopathy (SAE) is a severe neurological syndrome marked by widespread brain dysfunctions due to sepsis. Despite increasing data supporting the hypothesis of neuronal damage, the exact mechanism of sepsis-related cognitive disorders and therapeutic strategies remain unclear and need further investigation. In this study, a sepsis model was established in C57 mice using lipopolysaccharide (LPS). The findings demonstrated that LPS exposure induced neuronal loss, synaptic and cognitive deficits accompanied by mitochondrial damage. Bioinformatics and western blot analyses demonstrated a significant increase in Lipocalin-2 (LCN2) during sepsis as a key hub gene involved in immune and neurological inflammation. Interestingly, the recombinant LCN2 protein exhibited similar effects on synaptic dysfunction and cognitive deficits in C57 mice. Conversely, downregulating LCN2 effectively nullified the impact of LPS, leading to the amelioration of synaptic and cognitive deficits, neuronal loss, and reactive oxygen species (ROS)-associated mitochondrial damage. These findings suggest a novel etiopathogenic mechanism of SAE, which is initiated by the increased LCN2, leading to neuronal loss and cognitive deficit. Inhibition of LCN2 could be therapeutically beneficial in treating sepsis-induced synaptic and cognitive impairments.

Review on the Role of Mitochondrial Dysfunction in Septic Encephalopathy

Septic Encephalopathy (SE) is a frequent and severe complication of sepsis, characterized by a range of neurocognitive impairments from mild confusion to deep coma. The underlying pathophysiology of SE involves systemic inflammation, neuroinflammation, blood-brain barrier (BBB) disruption, and mitochondrial dysfunction. Among these factors, mitochondrial dysfunction plays a pivotal role, contributing to impaired ATP production, increased reactive oxygen species (ROS) generation, and activation of apoptotic pathways, all of which exacerbate neuronal damage and cognitive deficits. Diagnosis of SE relies on clinical evaluation, neuroimaging, electroencephalography (EEG), and laboratory tests, though specific diagnostic markers are still lacking. Epidemiological data show SE is prevalent in intensive care unit (ICU) patients, especially those with severe sepsis or septic shock, with incidence rates varying widely depending on the population and diagnostic criteria used. Recent research highlights the importance of mitochondrial dynamics, including biogenesis, fission, and fusion, in the development of SE. Mitophagy, a selective form of autophagy that degrades damaged mitochondria, plays a critical role in maintaining mitochondrial health and protecting against dysfunction. Targeting mitochondrial pathways and enhancing mitophagy offers a promising therapeutic strategy to mitigate the effects of SE, reduce oxidative stress, prevent apoptosis, and support the resolution of neuroinflammation. Further research is essential to elucidate the mechanisms of mitochondrial dysfunction and mitophagy in SE and develop effective interventions to improve patient outcomes.

The Effects of Ionotropic GABA Receptor Blockage on the Brain in Rats with Induced Sepsis

Encephalopathy following sepsis is defined as life-threatening organ failure due to the irregular response of the host to infection and has high mortality and morbidity rates. The present study aimed to investigate the effects of inflammation and the gamma-aminobutyric acid-A (GABAA) receptor antagonist, bicuculline, on brain tissue in rats with sepsis. Sepsis was experimentally generated using lipopolysaccharide (LPS). The rats were divided into four groups: control, LPS (10 mg/kg i.p.), bicuculline (1.5 mg/kg s.c.), and LPS+Bic. Electrophysiologic recordings and body temperature measurements were completed at the 24th hour, and samples were taken. TNF-α, IL-10, GABA, and MDA levels were measured. Tissue imaging was performed using S100-ß, NEUN, and synaptophysin antibodies. One-way ANOVA followed by the Tukey test was performed for statistical analysis. Inflammatory parameters significantly increased in brain tissue in the LPS group compared with the other groups (TNF-α, [F (3.14) = 6.015, p = 0.042]; IL-10, [F (3.15) = 9.013, p = 0.02]). Tissue imaging results were as follows: S100-ß involvement increased, and NeuN and synaptophysin involvement decreased in the LPS group [F (3.21) = 18.016, p = 0.006, for S100-ß; F (3.21) = 19.071, p = 0.003, for NeuN; F (3.21) = 18.098, p = 0.005, for synaptophysin]. In electrophysiologic recordings, we observed activity consistent with acute non-focal seizures in the LPS group. Contrarily, the control and other comparison groups exhibited normal resting neural activity. Bicuculline may be used as a therapeutic agent in sepsis to maintain the neurotransmitter and pro- and anti-inflammatory cytokine balance and reduce lipid peroxidation with its effects of acetylcholine esterase inhibition and GABAA receptor antagonism.

Frailty as an independent risk factor for sepsis-associated delirium: a cohort study of 11,740 older adult ICU patients

BACKGROUND

Sepsis-associated delirium (SAD) is a common complication in intensive care unit (ICU) patients and is associated with increased mortality. Frailty, characterized by diminished physiological reserves, may influence the development of SAD, but this relationship remains poorly understood.

AIMS

To comprehensively analyze the assessment of frailty as a predictive factor for sepsis-associated delirium in older adults.

METHODS

A retrospective cohort analysis was performed on sepsis patients aged ≥ 65 years admitted to the ICU. Frailty was assessed using the Modified Frailty Index based on 11 items including comorbidities and functional status. Patients were categorized into non-frail (MFI: 0-2) and frail (MFI ≥ 3) groups. Delirium was assessed using the ICU Confusion Assessment Method (CAM-ICU) and retrospective nursing notes. Logistic regression analysis was used to examine the relationship between frailty in older patients and the risk of delirium, and odds ratios (OR) and their 95% confidence intervals (CI) were calculated.

RESULTS

Among 11,740 patients (median age approximately 76 years [interquartile range: 70.47-83.14], 44.3% female), frail patients tended to have longer ICU stays, higher severity scores, and potentially worse clinical outcomes. The study found a significant positive association between MFI and the risk of developing SAD (OR: 1.13, 95% CI: 1.09-1.17, p < 0.001). Additionally, frail patients had a higher risk of developing SAD compared to non-frail patients (OR: 1.31, 95% CI: 1.20-1.43, p < 0.001).

CONCLUSIONS

Frailty independently predicts SAD development in older adults with sepsis in the ICU, emphasizing the importance of early recognition and prevention.

High Concentration Hydrogen Protects Sepsis-Associated Encephalopathy by Enhancing Pink1/Parkin-Mediated Mitophagy and Inhibiting cGAS-STING-IRF3 Pathway

BACKGROUND

Sepsis-associated encephalopathy (SAE) leads to increased mortality. Hydrogen (H2) has been proven to be effective in protecting against SAE. This study aimed to investigate the protective mechanism of a high concentration of H2 (HCH) (67%) against SAE.

METHODS

A mouse sepsis model was established via cecal ligation and puncture (CLP). 67% H2 was inhaled for 1 h at 1 h and 6 h after the operation. First, mice were randomly divided into 5 groups: Sham, CLP, CLP + CQ (a mitophagy inhibitor), CLP + H2, and CLP + H2 + CQ. Seven-day survival, cognitive function, and hippocampal damage were assessed. Then, mice were randomly divided into four groups: Sham, CLP, CLP + UA (a mitophagy agonist), and CLP + H2. Seven-day survival was recorded, cognitive function was assessed via Y-maze and Morris water maze tests, and hippocampal damage was evaluated via Nissl staining. Phosphorylated tau, inflammatory factors, ATP, and antioxidant enzyme levels and mitochondrial membrane potential (MMP) were detected. Mitochondria were observed via transmission electron microscopy. The protein levels of the PINK1/Parkin pathway and STING-TBK-IRF3 pathway were detected via western blotting.

RESULTS

HCH inhalation improves 7-day survival and cognitive function in septic mice and reduces brain tissue damage, proinflammatory cytokine levels, and phosphorylated tau levels. These effects were reversed by a mitophagy inhibitor. HCH significantly improves mitochondrial function, enhances PINK1/Parkin-mediated mitophagy, and reduces the activity of the STING-TBK-IRF3 pathway in brain tissue.

CONCLUSIONS

HCH inhalation effectively improved the survival rate of septic mice, alleviated SAE, and reduced tau phosphorylation. The mechanism may involve HCH enhancing PINK1/Parkin-mediated mitophagy, which inhibits the activity of the cGAS-STING-IRF3 pathway, thereby reducing neuroinflammation.

Pericytes mediate neuroinflammation via Fli-1 in endotoxemia and sepsis in mice

BACKGROUND

Sepsis-associated encephalopathy (SAE) often results from neuroinflammation. Recent studies have shown that brain platelet-derived growth factor receptor β (PDGFRβ) cells, including pericytes, may act as early sensors of infection by secreting monocyte chemoattractant protein-1 (MCP-1), which transmits inflammatory signals to the central nervous system. The erythroblast transformation-specific (ETS) transcription factor Friend leukemia virus integration 1 (Fli-1) plays a critical role in inflammation by regulating the expression of key cytokines, including MCP-1. However, the role of pericyte Fli-1 in neuroinflammation during sepsis remains largely unknown.

METHODS

WT and pericyte-specific Fli-1 knockout mice were subjected to endotoxemia through LPS injection or sepsis via cecal ligation and puncture (CLP). In vitro, Fli-1 was knocked down using small interfering RNA in cultured mouse brain pericytes, followed by LPS stimulation.

RESULTS

Elevated Fli-1 levels were observed in isolated brain pericytes 2 h after LPS administration, in brain tissues 4 h after CLP, and in cultured mouse brain pericytes 2 h after LPS stimulation in vitro. In endotoxemic mice, pericyte-specific Fli-1 knockout reduced expression of MCP-1 and IL-6 in brain tissue 2 h after LPS injection. At 24 h post-LPS administration, protein levels of MCP-1 and IL-6, and microglia activation were suppressed in pericyte-Fli-1 knockout mice. Additionally, Fli-1 deficiency in pericytes significantly reduced MCP-1 and IL-6 mRNA levels in the brain tissue 4 h after CLP. Moreover, in cultured brain pericytes, Fli-1 knockdown markedly decreased MCP-1 and IL-6 levels after LPS stimulation. Notably, LPS stimulation increased Fli-1 levels via TLR4-Myd88 signaling, which subsequently led to elevated production of MCP-1 in brain pericytes.

CONCLUSIONS

Fli-1 in pericytes may serve as a crucial mediator of neuroinflammation during sepsis by directly regulating pivotal cytokines such as MCP-1 and IL-6. Therefore, Fli-1 has the potential to serve as a therapeutic target in SAE and other neuroinflammatory disorders.

The Role of Ultrasonographic Assessment of Optic Nerve Sheath Diameter in Prediction of Sepsis-Associated Encephalopathy: Prospective Observational Study

BACKGROUND

Ultrasonographic optic nerve sheath diameter (ONSD) is a satisfactory noninvasive intracranial pressure (ICP) monitoring test. Our aim was to evaluate ONSD as an objective screening tool to predict and diagnose ICP changes early in sepsis-associated encephalopathy (SAE).

METHODS

Our prospective observational study was conducted on patients with sepsis, and after intensive care unit (ICU) admission, the time to diagnose SAE was recorded, and patients were divided into a non-SAE group including conscious patients with sepsis and a SAE group including patients with sepsis with acute onset of disturbed conscious level. ONSD was measured within 24 h of ICU admission for all patients and then every other day for up to 10 consecutive days until ICU discharge or death. The primary outcome was to compare ONSD measurements of both groups to find if there was a correlation between ONSD and SAE occurrence.

RESULTS

Eighty-nine patients with sepsis were divided into a non-SAE group (n = 45) and an SAE group (n = 44). ONSD showed a statistically significant difference at day 0 and a highly significant difference at days 2, 4, 6, 8, and 10. Day 2 ONSD had the best accuracy for predicting SAE, with a cutoff > 5.2 mm (sensitivity of 93.2%, specificity of 100%), a statistically positive correlation with the Sequential Organ Failure Assessment score (r = 0.485, P < 0.001) and ICU length of stay (r = 0.238, P < 0.001), and a statistically significant wider in patients who died compared to those who survived (P < 0.001).

CONCLUSIONS

ONSD could be an objective screening method for early diagnosis of SAE, with a cutoff > 5.2 mm. Trial registration NCT05849831 ( https://clinicaltrials.gov/study/NCT05849831 ).

Early systemic insults following severe sepsis-associated encephalopathy of critically ill patients: association with mortality and awakening-an analysis of the OUTCOMEREA database

BACKGROUND

Sepsis-associated encephalopathy (SAE) may be worsened by early systemic insults. We aimed to investigate the association of early systemic insults with outcomes of critically ill patients with severe SAE.

METHODS

We performed a retrospective analysis using data from the French OUTCOMEREA prospective multicenter database. We included patients hospitalized in intensive care unit (ICU) for at least 48 h with severe SAE (defined by a score on the Glasgow Coma Scale (GCS) ≤ 13 and severe sepsis or septic shock (SEPSIS 2.0 criteria)) requiring invasive ventilation and who had no primary brain injury. We analyzed early systemic insults (abnormal glycemia (< 3 mmol/L or ≥ 11 mmol/L), hypotension (diastolic blood pressure ≤ 50 mmHg), temperature abnormalities (< 36 °C or ≥ 38.3 °C), anemia (hematocrit < 21%), dysnatremia (< 135 mmol/L or ≥ 145 mmol/L), oxygenation abnormalities (PaO2 < 60 or > 200 mmHg), carbon dioxide abnormalities (< 35 mmHg or ≥ 45 mmHg), and the impact of their correction at day 3 on day-28 mortality and awakening, defined as a recovery of GCS > 13.

RESULTS

We included 995 patients with severe SAE, of whom 883 (89%) exhibited at least one early systemic insult that persisted through day 3. Compared to non-survivors, survivors had significantly less early systemic insults (hypoglycemia, hypotension, hypothermia, and anemia) within the first 48 h of ICU admission. The absence of correction of the following systemic insults at day 3 was independently associated with mortality: blood pressure (adjusted hazard ratio (aHR) = 1.77, 95% confidence interval (CI) 1.34-2.34), oxygenation (aHR = 1.78, 95% CI 1.20-2.63), temperature (aHR = 1.46, 95% CI 1.12-1.91) and glycemia (aHR = 1.41, 95% CI 1.10-1.80). Persistent abnormal blood pressure, temperature and glycemia at day 3 were associated with decreased chances of awakening.

CONCLUSIONS

In patients with severe SAE, the persistence of systemic insults within the first three days of ICU admission is associated with increased mortality and decreased chances of awakening.

Protective Effects of Mdivi-1 on Cognition Disturbance Following Sepsis in Mice via Alleviating Microglia Activation and Polarization

BACKGROUND

Neuroinflammation is one of the essential pathogeneses of cognitive damage suffering from sepsis-associated encephalopathy (SAE). Lots of evidences showed the microglia presented mitochondrial fragmentation during SAE. This study investigated the protective effects and novel mechanisms of inhibiting microglia mitochondrial fragmentation via mitochondrial division inhibitor 1 (Mdivi-1) on cognitive damage in SAE.

METHODS

The SAE model was performed by cecal ligation and puncture (CLP), and Mdivi-1 was administrated via intraperitoneal injection. Morris water maze was performed to assess cognitive function. Mitochondrial morphology was observed by electron microscope or MitoTracker staining. The qRT-PCR, immunofluorescence staining, and western blots were used to detect the inflammatory factors and protein content, respectively. Flow cytometry was used to detect the polarization of hippocampal microglia. Bioinformatics analysis was used to verify hypotheses.

RESULTS

Mdivi-1 administration alleviated sepsis-induced mitochondrial fragmentation, microglia activation, polarization, and cognitive damage. The mechanisms study showed neuroinflammation and oxidative stress were suppressed via NF-κB and Keap1/Nrf2/HO-1 pathways following Mdivi-1 administration; meanwhile, pyroptosis in microglia was reduced, which was associated with enhanced autophagosome formation via p62 elevation following Mdivi-1 administration.

CONCLUSION

Inhibition of microglia mitochondrial fragmentation is beneficial to SAE cognitive disturbance, the mechanisms are related to alleviating neuroinflammation, oxidative stress, and pyroptosis.

Prognostic analysis of elderly patients with pathogenic microorganisms positive for sepsis-associated encephalopathy

Objectives

Sepsis-associated encephalopathy (SAE) has a high incidence and mortality, especially for elderly patients and patients who are positive for pathogenic microbial infection, this study explored the prognostic factors influencing the prognosis of elderly patients with pathogenic microorganisms positive of sepsis-associated encephalopathy.

Methods

Patients with SAE and pathogenic microbiology positive were included in this study from Medical Information Mart for Intensive Care IV (MIMIC IV) database. The main results of this study was analyzed the 28-day mortality rate of patients with pathogenic microorganism positive and SAE by Wilcoxon, Kaplan-Meier curve and other methods.

Results

This study found that older patients with SAE had higher mortality at 28 and 90 days compared with non-older patients with SAE. Klebsiella pneumoniae and Pseudomonas aeruginosa infection, the level of APTT and lactate and SAPS III score were independent risk factors for 28-day mortality in elderly patients with SAE, among them, Klebsiella pneumoniae and Pseudomonas aeruginosa infection had the best sensitivity (0.893; 0.931) in assessing elderly patients with pathogenic microorganisms positive and SAE; the SAPS III score had the highest AUC (0.681) value and specificity (0.761) in assessing elderly patients with pathogenic microorganisms positive and SAE.

Conclusion

The older patients with SAE had a poor prognosis, the elder patients with pathogenic microorganisms positive and SAE with high levels of APTT and lactate and SAPS III score and Klebsiella pneumoniae and Pseudomonas aeruginosa infection should be closely monitored and treated aggressively.

The Role and Mechanism of Metformin in the Treatment of Nervous System Diseases

Nervous system diseases represent a significant global burden, affecting approximately 16% of the world's population and leading to disability and mortality. These conditions, encompassing both central nervous system (CNS) and peripheral nervous system (PNS) disorders, have substantial social and economic impacts. Metformin, a guanidine derivative derived from a plant source, exhibits therapeutic properties in various health conditions such as cancer, aging, immune-related disorders, polycystic ovary syndrome, cardiovascular ailments, and more. Recent studies highlight metformin's ability to cross the blood-brain barrier, stimulate neurogenesis, and provide beneficial effects in specific neurological disorders through diverse mechanisms. This review discusses the advancements in research on metformin's role and mechanisms in treating neurological disorders within both the central and peripheral nervous systems, aiming to facilitate further investigation, utilization, and clinical application of metformin in neurology.

Effect of endothelial responses on sepsis-associated organ dysfunction

ABSTRACT

Sepsis-related organ dysfunction is associated with increased morbidity and mortality. Previous studies have found that the endothelium plays crucial roles in maintaining the vascular permeability during sepsis, as well as in regulating inflammation and thrombosis. During sepsis, endothelial cells may release cytokines, chemokines, and pro-coagulant factors, as well as express adhesion molecules. In general, endothelial responses during sepsis typically inhibit bacterial transmission and coordinate leukocyte recruitment to promote bacterial clearance. However, excessive or prolonged endothelial activation can lead to impaired microcirculation, tissue hypoperfusion, and organ dysfunction. Given the structural and functional heterogeneity of endothelial cells in different organs, there are potential differences in endothelial responses by organ type, and the risk of organ damage may vary accordingly. This article reviews the endothelial response observed in sepsis and its effects on organ function, summarizes current progress in the development of therapeutic interventions targeting the endothelial response, and discusses future research directions to serve as a reference for researchers in the field.

Diagnostic Approach to the Patient with Altered Mental Status

Acute encephalopathy is a common presenting symptom in the emergency room and complicates many hospital and intensive care unit admissions. The evaluation of patients with encephalopathy poses several challenges: limited history and examination due to the patient's mental status, broad differential diagnosis of systemic and neurologic etiologies, low yield of neurodiagnostic testing due to the high base rate of systemic causes, and the importance of identifying less common neurologic causes of encephalopathy that can be life-threatening if not identified and treated. This article discusses the differential diagnosis of acute encephalopathy, presents an approach to the history and examination in a patient with encephalopathy, reviews the literature on the yield of neurodiagnostic testing in this population, and provides a diagnostic framework for the evaluation of patients with altered mental status.

Brain Ultrasonography in Critically Ill Septic Patients: A Scoping Review

Sepsis-associated encephalopathy (SAE) is linked to high mortality and impaired neurologic outcome. Brain ultrasonography (US) is a non-invasive tool for cerebral monitoring. A scoping review of the literature in three databases was performed to answer if brain perfusion is altered in sepsis, to determine the role of brain US in guiding resuscitation and its ability to predict the outcome. Randomized controlled trials, clinical trials, observational studies, and systematic reviews on adults with sepsis or septic shock in the ICU were included. A total of 625 articles were screened, and 34 included. There were 85% observational studies and 15% systematic reviews with or without meta-analysis. The majority of studies had a small sample size and used different metrics. The studies focused on cerebral blood flow (CBF) alterations reporting variable results (CBF increased, normal, or decreased). The findings showed a variable rate of cerebral autoregulation (CAR) impairment, with higher incidence in the early stages of sepsis and associations with poor neurological outcomes. However, the impact of CAR and CBF alterations on neurological outcomes and mortality was not clear. Very few studies were found on resuscitation. In conclusion, brain US can identify cerebral perfusions alterations and its usage in sepsis is promising. However, the current body of evidence for its usage is poor and lacks standardization.

Dichloroacetate attenuates brain injury through inhibiting neuroinflammation and mitochondrial fission in a rat model of sepsis-associated encephalopathy

Sepsis-associated encephalopathy (SAE) is a severe complication of sepsis, characterized by neuroinflammation, mitochondrial dysfunction, and oxidative stress, leading to cognitive decline and high mortality. The effectiveness of dichloroacetate (DCA) in modulating mitochondrial function provides a novel therapeutic strategy for SAE. In this study, we evaluated the neuroprotective effects of DCA in a rat model of SAE induced by cecal ligation and puncture (CLP). Rats treated with DCA exhibited significant improvements in neurological function and survival, as evidenced by less neuron loss from histopathologic analysis, restored neurologic deficit scores, improved Y-maze alternation percentages, and enhanced recognition index performance. Biochemical analyses showed that DCA administration at 25 mg/kg and 100 mg/kg reduced astrocyte and microglial activation, indicating reduced neuroinflammation. Furthermore, DCA simultaneously reduced the production of circulating and cerebral inflammatory cytokines (including TNF-α, IL-1β, and IL-10), concomitant with mitigating oxidative stress through down-regulating expression of 8-Hydroxy-2'-deoxyguanosine (8-OHdG) and reactive oxygen species (ROS) in the brain. Mechanistically, DCA modulated mitochondrial dynamics by suppressing Drp1 and pDrp1 expression, which are indicators of mitochondrial fission. This was corroborated by transmission electron microscopy, quantification of mitochondrial area, and Western blot analyses. Furthermore, DCA treatment improved ATP levels, mitochondrial complex I activity, and NAD+/NADH ratio, indicating a significant attenuation of brain mitochondrial dysfunction. In conclusion, our findings suggest that DCA confers neuroprotection in SAE by curtailing neuroinflammation and mitochondrial fission, outlining a promising therapeutic strategy for treating SAE in critically ill patients.

A Multivariate Phenotypical Approach of Sepsis and Septic Shock-A Comprehensive Narrative Literature Review

Despite medical advances, sepsis and septic shock remain some of the leading causes of mortality worldwide, with a high inter-individual variability in prognosis, clinical manifestations and response to treatment. Evidence suggests that pulmonary sepsis is one of the most severe forms of sepsis, while liver dysfunction, left ventricular dysfunction, and coagulopathy impact the prognostic. Sepsis-related hypothermia and a hypoinflammatory state are related to a poor outcome. Given the heterogeneity of sepsis and recent technological progress amongst machine learning analysis techniques, a new, personalized approach to sepsis is being intensively studied. Despite the difficulties when tailoring a targeted approach, with the use of artificial intelligence-based pattern recognition, more and more publications are becoming available, highlighting novel factors that may intervene in the high heterogenicity of sepsis. This has led to the devise of a phenotypical approach in sepsis, further dividing patients based on host and trigger-related factors, clinical manifestations and progression towards organ deficiencies, dynamic prognosis algorithms, and patient trajectory in the Intensive Care Unit (ICU). Host and trigger-related factors refer to patients' comorbidities, body mass index, age, temperature, immune response, type of bacteria and infection site. The progression to organ deficiencies refers to the individual particularities of sepsis-related multi-organ failure. Finally, the patient's trajectory in the ICU points out the need for a better understanding of interindividual responses to various supportive therapies. This review aims to identify the main sources of variability in clustering septic patients in various clinical phenotypes as a useful clinical tool for a precision-based approach in sepsis and septic shock.

Extracellular vesicles in sepsis plasma mediate neuronal inflammation in the brain through miRNAs and innate immune signaling

BACKGROUND

Neuroinflammation reportedly plays a critical role in the pathogenesis of sepsis-associated encephalopathy (SAE). We previously reported that circulating plasma extracellular vesicles (EVs) from septic mice are proinflammatory. In the current study, we tested the role of sepsis plasma EVs in neuroinflammation.

METHODS

To track EVs in cells and tissues, HEK293T cell-derived EVs were labeled with the fluorescent dye PKH26. Cecal ligation and puncture (CLP) was conducted to model polymicrobial sepsis in mice. Plasma EVs were isolated by ultracentrifugation and their role in promoting neuronal inflammation was tested following intracerebroventricular (ICV) injection. miRNA inhibitors (anti-miR-146a, -122, -34a, and -145a) were applied to determine the effects of EV cargo miRNAs in the brain. A cytokine array was performed to profile microglia-released protein mediators. TLR7- or MyD88-knockout (KO) mice were utilized to determine the underlying mechanism of EVs-mediated neuroinflammation.

RESULTS

We observed the uptake of fluorescent PKH26-EVs inside the cell bodies of both microglia and neurons. Sepsis plasma EVs led to a dose-dependent cytokine release in cultured microglia, which was partially attenuated by miRNA inhibitors against the target miRNAs and in TLR7-KO cells. When administered via the ICV, sepsis plasma EVs resulted in a marked increase in the accumulation of innate immune cells, including monocyte and neutrophil and cytokine gene expression, in the brain. Although sepsis plasma EVs had no direct effect on cytokine production or neuronal injury in vitro, the conditioned media (CM) of microglia treated with sepsis plasma EVs induced neuronal cell death as evidenced by increased caspase-3 cleavage and Annexin-V staining. Cytokine arrays and bioinformatics analysis of the microglial CM revealed multiple cytokines/chemokines and other factors functionally linked to leukocyte chemotaxis and migration, TLR signaling, and neuronal death. Moreover, sepsis plasma EV-induced brain inflammation in vivo was significantly dependent on MyD88.

CONCLUSIONS

Circulating plasma EVs in septic mice cause a microglial proinflammatory response in vitro and a brain innate immune response in vivo, some of which are in part mediated by TLR7 in vitro and MyD88 signaling in vivo. These findings highlight the importance of circulating EVs in brain inflammation during sepsis.

ADSC-derived exosomes provide neuroprotection in sepsis-associated encephalopathy by regulating hippocampal pyroptosis

AIMS

Adipose-derived stem cell (ADSC)-derived exosomes have been recognized for their neuroprotective effects in various neurological diseases. This study investigates the potential neuroprotective effects of ADSC-derived exosomes in sepsis-associated encephalopathy (SAE).

METHODS

Behavioral cognitive functions were evaluated using the open field test, Y-maze test, and novel object recognition test. Brain activity was assessed through functional magnetic resonance imaging (fMRI). Pyroptosis was measured using immunofluorescence staining and western blotting.

RESULTS

Our findings indicate that ADSC-derived exosomes mitigate cognitive impairment, improve survival rates, and prevent weight loss in SAE mice. Additionally, exosomes protect hippocampal function in SAE mice, as demonstrated by fMRI evaluations. Furthermore, SAE mice exhibit neuronal damage and infiltration of inflammatory cells in the hippocampus, conditions which are reversed by exosome treatment. Moreover, our study highlights the downstream regulatory role of the NLRP3/caspase-1/GSDMD signaling pathway as a crucial mechanism in alleviating hippocampal inflammation.

CONCLUSION

ADSC-derived exosomes confer neuroprotection in SAE models by mediating the NLRP3/caspase-1/GSDMD pathway, thereby ameliorating cognitive impairment.

The Correlation of Hemostatic Parameters with the Development of Early Sepsis-Associated Encephalopathy. A Retrospective Observational Study

Introduction

Sepsis-associated encephalopathy (SAE) is one of the most common complications seen both in early and late stages of sepsis, with a wide spectrum of clinical manifestations ranging from mild neurological dysfunction to delirium and coma. The pathophysiology of SAE is still not completely understood, and the diagnosis can be challenging especially in early stages of sepsis and in patients with subtle symptoms.

Aim of the study

The objective of this study was to assess the coagulation profile in patients with early SAE and to compare the hemostatic parameters between septic patients with and without SAE in the first 24 hours from sepsis diagnosis.

Material and methods

This retrospective observational study included 280 patients with sepsis in the first 24 hours after sepsis diagnosis. A complete blood count was available in all patients; a complex hemostatic assessment including standard coagulation tests, plasmatic levels of coagulation factors, inhibitors, D-dimers, and Rotation thromboelastometry (ROTEM, Instrumentation Laboratory) was performed in a subgroup of patients.

Results

Early SAE was diagnosed in 184 patients (65.7%) and was correlated with a higher platelet count, after adjusting for age and leucocyte count. Compared to patients without neurological dysfunction, patients with early SAE presented a more active coagulation system revealed by faster propagation phase, increased clot firmness and elasticity with a higher platelet contribution to clot strength. The initiation of coagulation and clot lysis were not different between the groups.

Conclusion

In the early stages of sepsis, the development of SAE is correlated with increased systemic clotting activity where platelets seem to have an important role. More research is needed to investigate the role of platelets and the coagulation system in relation to the development of early SAE.

Phosphatidylserine improves aging sepsis survival, modulates gut microbiome, and prevents sepsis-associated encephalopathy

Aged adults are prone to both short- and long-term complications following sepsis due to ineffective therapy. Phosphatidylserine (PS) is a membrane nutrient supplement known to enhance cognition and brain function, but its potential effects in treating sepsis are not well-documented. Our study aimed to explore the potential of PS in improving outcomes in sepsis and sepsis-associated encephalopathy (SAE). Middle-aged mice were administered PS for two months following induction of sepsis by lipopolysaccharides. The results indicated a significant increase in the survival rate of mice treated with PS after sepsis. Surviving mice underwent open field and shuttle box tests 45 days post-sepsis, revealing potential alleviation of neurobehavioral impairments due to PS pretreatment. Analysis at 60 days post-sepsis euthanasia showed reduced cleaved-caspase 3 in neurons and glial cell markers in the PS-treated group compared to the untreated sepsis group. Furthermore, PS administration effectively reduced proinflammatory cytokine gene expression in the hippocampus of mice with SAE, potentially inhibiting the TBK1/NLRP3/ASC signaling pathway. In the gut, PS pretreatment modulated β-diversity while maintaining jejunal morphology and colon ZO-1 expression, without significantly affecting α-diversity indices. Our findings suggest that PS administration improves survival rates, modulates the gut microbiome, preserves gut integrity, and ameliorates brain pathology in survived mice after sepsis. Importantly, these findings have significant implications for sepsis treatment and cognitive function preservation in aging individuals, providing new insights and sparking further interest and investigation into the potential of PS in sepsis treatment.

High-concentration hydrogen inhalation mitigates sepsis-associated encephalopathy in mice by improving mitochondrial dynamics

BACKGROUND

Sepsis-associated encephalopathy (SAE) is a neuronal injury with poor prognosis. Mitochondrial dysfunction is critical in SAE development, and hydrogen gas (H2) has a protective effect on septic mice. This study aimed to investigate the effect of high concentration (67%) of H2 on SAE and whether it is related to mitochondrial biogenesis and mitochondrial dynamics.

METHODS

A mouse sepsis model was induced by cecal ligation and puncture. The mice inhalated 67% H2 for 1 h at 1 and 6 h post-surgery, respectively. The 7-day survival rate was recorded. Cognitive function was assessed using the Y-maze test and Morris water maze test. Serum inflammatory factors, antioxidant enzymes, as well as mitochondrial function indexes including mitochondrial membrane potential (MMP) and ATP in the hippocampal tissue were evaluated 24 h after surgery. Mitochondrial dynamic proteins (DRP1 and MFN2) and biosynthetic proteins (PGC-1α, NRF2, and TFAM) in the hippocampal tissue were detected. Moreover, the morphology of mitochondria was observed by transmission electron microscopy.

RESULTS

Inhalation of 67% H2 improved the 7-day survival rates and recognition memory function of septic mice, alleviated brain antioxidant enzyme activity (SOD and CAT), and reduced serum proinflammatory cytokine levels. H2 inhalation also enhanced the expression of MFN2 and mitochondrial biogenesis-related factors (PGC-1α, NRF2, and TFAM) and decreased the expression of fission protein (DRP1), leading to improvement in mitochondrial function, as evidenced by MMP and ATP levels.

CONCLUSIONS

Inhalation of high concentration (67%) of H2 in septic mice improved the survival rate and reduced neuronal injury. Its mechanism might be mediated by enhancing mitochondrial biogenesis and mitochondrial dynamics.

Dichloroacetate Prevents Sepsis Associated Encephalopathy by Inhibiting Microglia Pyroptosis through PDK4/NLRP3

Dichloroacetate (DCA), a pyruvate dehydrogenase kinase inhibitor, is often used to treat lactic acidosis and malignant tumors. Increasing studies have shown that DCA has neuroprotective effects. Here, we explored the role and mechanism of DCA in Sepsis associated encephalopathy (SAE). Single-cell analysis was used to determine the important role of PDK4 in SAE and identify the cell type. GO and GSEA analysis were used to determine the correlation between DCA and pyroptosis. Through LPS + ATP stimulation, a microglia pyroptosis model was established to observe the expression level of intracellular pyroptosis-related proteins under DCA intervention, and further detect the changes in intracellular ROS and JC-1. Additionally, a co-culture environment of microglia and neuron was simply constructed to evaluate the effect of DCA on activated microglia-mediated neuronal apoptosis. Finally, Novel object recognition test and the Morris water maze were used to explore the effect of DCA on cognitive function in mice from different groups after intervention. Based on the above experiments, this study concludes that DCA can improve the ratio of peripheral and central M1 macrophages, inhibit NLRP3-mediated pyroptosis through ROS and mitochondrial membrane potential (MMP). DCA can reduce neuron death caused by SAE and improve cognitive function in LPS mice. In SAE, DCA may be a potential candidate drug for the treatment of microglia-mediated neuroinflammation.

Pleiotropic role of endoplasmic reticulum stress in the protection of psoralidin against sepsis-associated encephalopathy

Sepsis-associated encephalopathy (SAE) is a severe complication that affects the central nervous system and is a leading cause of increased morbidity and mortality in intensive care units. Psoralidin (PSO), a coumarin compound isolated from the traditional Chinese medicine Psoralea corylifolia L., can penetrate the blood-brain barrier and has various pharmacological activities, including anti-inflammation, anti-oxidation and anti-depression. This study aims to explore whether PSO alleviates SAE and delve into the underlying mechanisms. We found that PSO treatment significantly reduced sepsis scores, aspartate transaminase (AST) and aspartate transaminase (LDH), while increased anal temperature and neurological scores in CLP-injured mice. Moreover, PSO treatment ameliorated sepsis-associated cognitive impairment, mood, anxiety disorders, inhibited inflammatory responses, as well as attenuated endoplasmic reticulum stress (ERS). These results were also validated in vitro experiments, PSO treatment reduced ROS, inflammation response, and attenuated ERS in LPS-injured N2a cells. Importantly, tunicamycin (TUN), as ERS agonist, significantly reversed the protective effect of PSO on LPS-injured N2a cells, as evidenced by increased expression levels of IL-6, NLRP3, CHOP, and ATF6. Likewise, ATF6 overexpression also reversed the protective effect of PSO. In conclusion, these results confirmed that PSO has a protective effect on SAE, which was largely attributed to neuroinflammation and ERS. These findings provide new insights into the neuroprotective role of PSO and suggest that PSO is a new therapeutic intervention of SAE.

3-Methyladenine attenuates neuroinflammation and improves cognitive function in sepsis-associated encephalopathy by inhibiting autophagy

OBJECTIVE

Sepsis-associated encephalopathy (SAE) can lead to severe cerebral dysfunction as well as cognitive dysfunction, resulting in a significant disease burden. 3-Methyladenine (3-MA) has been confirmed to have anti-inflammatory effects on diseases characterized by enhanced autophagy. However, its role in SAE has not been clarified.

METHODS

An SAE mouse model was generated by intraperitoneal injection of lipopolysaccharide (LPS). Mice were given 5, 20, or 80 mg/kg 3-MA to determine the therapeutic dose. The mice in the different groups were given 20 mg/kg 3-MA or saline, and survival, body temperature, body weight and neurobehavioral scores were measured at different time points. The expression of autophagy-related proteins and inflammatory factors was detected by Western blotting, enzyme linked immunosorbent assay (ELISA) and real-time quantitative polymerase chain reaction (RT-qPCR) 12 h after LPS induction. Glial activation and neuronal injury in the hippocampus were detected by immunofluorescence staining and HE staining. The open Field test, novel object recognition (NOR) test, Y-maze test, and Morris water maze (MWM) test were performed to assess cognitive function.

RESULTS

Treatment with 20 or 80 mg/kg 3-MA reduced the increase in hippocampal TNF-α, IL-6, and IL-1β expression in SAE model mice, with 20 mg/kg 3-MA having the greatest therapeutic effect. Treatment with 20 mg/kg 3-MA effectively reduced the expression of hippocampal autophagy-related proteins and mortality, ameliorated hypothermia, decreased body weight and electroencephalography (EEG) performance, and attenuated the activation of neuroglia and neuronal damage. Moreover, it alleviated the cognitive dysfunction 2 weeks after LPS induction.

CONCLUSIONS

3-MA reduced neuroglial activation and neuronal damage, attenuated neuroinflammation, and improved cognitive deficits during recovery period by inhibiting autophagy in SAE.

Integrating single-nucleus RNA sequencing and spatial transcriptomics to elucidate a specialized subpopulation of astrocytes, microglia and vascular cells in brains of mouse model of lipopolysaccharide-induced sepsis-associated encephalopathy

BACKGROUND

Understanding the mechanism behind sepsis-associated encephalopathy (SAE) remains a formidable task. This study endeavors to shed light on the complex cellular and molecular alterations that occur in the brains of a mouse model with SAE, ultimately unraveling the underlying mechanisms of this condition.

METHODS

We established a murine model using intraperitoneal injection of lipopolysaccharide (LPS) in wild type and Anxa1-/- mice and collected brain tissues for analysis at 0-hour, 12-hour, 24-hour, and 72-hour post-injection. Utilizing advanced techniques such as single-nucleus RNA sequencing (snRNA-seq) and Stereo-seq, we conducted a comprehensive characterization of the cellular responses and molecular patterns within the brain.

RESULTS

Our study uncovered notable temporal differences in the response to LPS challenge between Anxa1-/- (annexin A1 knockout) and wild type mice, specifically at the 12-hour and 24-hour time points following injection. We observed a significant increase in the proportion of Astro-2 and Micro-2 cells in these mice. These cells exhibited a colocalization pattern with the vascular subtype Vas-1, forming a distinct region known as V1A2M2, where Astro-2 and Micro-2 cells surrounded Vas-1. Moreover, through further analysis, we discovered significant upregulation of ligands and receptors such as Timp1-Cd63, Timp1-Itgb1, Timp1-Lrp1, as well as Ccl2-Ackr1 and Cxcl2-Ackr1 within this region. In addition, we observed a notable increase in the expression of Cd14-Itgb1, Cd14-Tlr2, and Cd14-C3ar1 in regions enriched with Micro-2 cells. Additionally, Cxcl10-Sdc4 showed broad upregulation in brain regions containing both Micro-2 and Astro-2 cells. Notably, upon LPS challenge, there was an observed increase in Anxa1 expression in the mouse brain. Furthermore, our study revealed a noteworthy increase in mortality rates following Anxa1 knockdown. However, we did not observe substantial differences in the types, numbers, or distribution of other brain cells between Anxa1-/- and wildtype mice over time. Nevertheless, when comparing the 24-hour post LPS injection time point, we observed a significant decrease in the proportion and distribution of Micro-2 and Astro-2 cells in the vicinity of blood vessels in Anxa1-/- mice. Additionally, we noted reduced expression levels of several ligand-receptor pairs including Cd14-Tlr2, Cd14-C3ar1, Cd14-Itgb1, Cxcl10-Sdc4, Ccl2-Ackr1, and Cxcl2-Ackr1.

CONCLUSIONS

By combining snRNA-seq and Stereo-seq techniques, our study successfully identified a distinctive cellular colocalization, referred to as a special pathological niche, comprising Astro-2, Micro-2, and Vas-1 cells. Furthermore, we observed an upregulation of ligand-receptor pairs within this niche. These findings suggest a potential association between this cellular arrangement and the underlying mechanisms contributing to SAE or the increased mortality observed in Anxa1 knockdown mice.

Research progress in the pathogenesis of sepsis-associated encephalopathy

Sepsis is a syndrome that causes dysfunction of multiple organs due to the host's uncontrolled response to infection and is a significant contributor to morbidity and mortality in intensive care units worldwide. Surviving patients are often left with acute brain injury and long-term cognitive impairment, known as sepsis-associated encephalopathy (SAE). In recent years, researchers have directed their focus towards the pathogenesis of SAE. However, due to the complexity of its development, there remains a lack of effective treatment measures that arise as a serious issue affecting the prognosis of sepsis patients. Further research on the possible causes of SAE aims to provide clinicians with potential therapeutic targets and help develop targeted prevention strategies. This paper aims to review recent research on the pathogenesis of SAE, in order to enhance our understanding of this syndrome.

Maresin 1 alleviates neuroinflammation and cognitive decline in a mouse model of cecal ligation and puncture

OBJECTIVES

Inflammation in the central nervous system plays a crucial role in the occurrence and development of sepsis-associated encephalopathy. This study aims to explore the effects of maresin 1 (MaR1), an anti-inflammatory and pro-resolving lipid mediator, on sepsis-induced neuroinflammation and cognitive impairment.

METHODS

Mice were randomly assigned to 4 groups: A sham group (sham operation+vehicle), a cecal ligation and puncture (CLP) group (CLP operation+vehicle), a MaR1-LD group (CLP operation+1 ng MaR1), and a MaR1-HD group (CLP operation+10 ng MaR1). MaR1 or vehicle was intraperitoneally administered starting 1 h before CLP operation, then every other day for 7 days. Survival rates were monitored, and serum inflammatory cytokines [tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β, and IL-6] were measured 24 h after operation using enzyme-linked immunosorbent assay (ELISA). Cognitive function was assessed 7 days after operation using the Morris water maze (MWM) test and novel object recognition (NOR) task. The mRNA expression of TNF-α, IL-1β, IL-6, inducible nitric oxide synthase (iNOS), IL-4, IL-10, and arginase 1 (Arg1) in cortical and hippocampal tissues was determined by real-time reverse transcription PCR (RT-PCR). Western blotting was used to determine the protein expression of iNOS, Arg1, signal transducer and activator of transcription 6 (STAT6), peroxisome proliferator-activated receptor gamma (PPARγ), and phosphorylated STAT6 (p-STAT6) in hippocampal tissue. Microglia activation was visualized via immunofluorescence. Mice were also treated with the PPARγ antagonist GW9662 to confirm the involvement of this pathway in MaR1's effects.

RESULTS

CLP increased serum levels of TNF-α, IL-1β, and IL-6, and reduced body weight and survival rates (all P<0.05). Both 1 ng and 10 ng doses of MaR1 significantly reduced serum TNF-α, IL-1β, and IL-6 levels, improved body weight, and increased survival rates (all P<0.05). No significant difference in efficacy was observed between the 2 doses (all P>0.05). MWM test and NOR task indicated that CLP impaired spatial learning, which MaR1 mitigated. However, GW9662 partially reversed MaR1's protective effects. Real-time RT-PCR results demonstrated that, compared to the sham group, mRNA expression of TNF-α, IL-1β, and iNOS significantly increased in hippocampal tissues following CLP (all P<0.05), while IL-4, IL-10, and Arg1 showed a slight decrease, though the differences were not statistically significant (all P>0.05). Compared to the CLP group, both 1 ng and 10 ng MaR1 decreased TNF-α, IL-1β, and iNOS mRNA expression in hippocampal tissues and increased IL-4, IL-10, and Arg1 mRNA expression (all P<0.05). Immunofluorescence results indicated a significant increase in Iba1-positive microglia in the hippocampus after CLP compared to the sham group (P<0.05). Administration of 1 ng and 10 ng MaR1 reduced the percentage area of Iba1-positive cells in the hippocampus compared to the CLP group (both P<0.05). Western blotting results showed that, compared to the CLP group, both 1 ng and 10 ng MaR1 down-regulated the iNOS expression, while up-regulated the expression of Arg1, PPARγ, and p-STAT6 (all P<0.05). However, the inclusion of GW9662 counteracted the MaR1-induced upregulation of Arg1 and PPARγ compared to the MaR1-LD group (all P<0.05).

CONCLUSIONS

MaR1 inhibits the classical activation of hippocampal microglia, promotes alternative activation, reduces sepsis-induced neuroinflammation, and improves cognitive decline.

Construction and validation of a nomogram prediction model for the progression to septic shock in elderly patients with urosepsis

Background

Septic shock is a clinical syndrome characterized by the progression of sepsis to a severe stage. Elderly patients with urosepsis in the intensive care unit (ICU) are more likely to progress to septic shock. This study aimed to establish and validate a nomogram model for predicting the risk of progression to septic shock in elderly patients with urosepsis.

Methods

We extracted data from the Medical Information Mart for Intensive Care (MIMIC-IV) and the eICU Collaborative Research Database (eICU-CRD). The MIMIC-IV dataset was split into a training set for model development and an internal validation set to assess model performance. Further external validation was performed using a distinct dataset sourced from the eICU-CRD. Predictors were screened using least absolute shrinkage and selection operator (LASSO) regression and multivariable logistic regression analyses. The evaluation of model performance included discrimination, calibration, and clinical usefulness.

Results

The study demonstrated that the Glasgow Coma Scale (GCS), white blood count (WBC), platelet, blood urea nitrogen (BUN), calcium, albumin, congestive heart failure (CHF), and invasive ventilation were closely associated with septic shock in the training cohort. Nomogram prediction, utilizing eight parameters, demonstrated strong predictive accuracy with area under the curve (AUC) values of 0.809 (95 % CI 0.786-0.834), 0.794 (95 % CI 0.756-0.831), and 0.723 (95 % CI 0.647-0.801) in the training, internal validation, and external validation sets, respectively. Additionally, the nomogram demonstrated a promising calibration performance and significant clinical usefulness in both the training and validation sets.

Conclusion

The constructed nomogram is a reliable and practical tool for predicting the risk of progression to septic shock in elderly patients with urosepsis. Its implementation in clinical practice may enhance the early identification of high-risk patients, facilitate timely and targeted interventions to mitigate the risk of septic shock, and improve patient outcomes.

Prognostic value of early EEG abnormalities in severe stroke patients requiring mechanical ventilation: a pre-planned analysis of the SPICE prospective multicenter study

INTRODUCTION

Prognostication of outcome in severe stroke patients necessitating invasive mechanical ventilation poses significant challenges. The objective of this study was to assess the prognostic significance and prevalence of early electroencephalogram (EEG) abnormalities in adult stroke patients receiving mechanical ventilation.

METHODS

This study is a pre-planned ancillary investigation within the prospective multicenter SPICE cohort study (2017-2019), conducted in 33 intensive care units (ICUs) in the Paris area, France. We included adult stroke patients requiring invasive mechanical ventilation, who underwent at least one intermittent EEG examination during their ICU stay. The primary endpoint was the functional neurological outcome at one year, determined using the modified Rankin scale (mRS), and dichotomized as unfavorable (mRS 4-6, indicating severe disability or death) or favorable (mRS 0-3). Multivariable regression analyses were employed to identify EEG abnormalities associated with functional outcomes.

RESULTS

Of the 364 patients enrolled in the SPICE study, 153 patients (49 ischemic strokes, 52 intracranial hemorrhages, and 52 subarachnoid hemorrhages) underwent at least one EEG at a median time of 4 (interquartile range 2-7) days post-stroke. Rates of diffuse slowing (70% vs. 63%, p = 0.37), focal slowing (38% vs. 32%, p = 0.15), periodic discharges (2.3% vs. 3.7%, p = 0.9), and electrographic seizures (4.5% vs. 3.7%, p = 0.4) were comparable between patients with unfavorable and favorable outcomes. Following adjustment for potential confounders, an unreactive EEG background to auditory and pain stimulations (OR 6.02, 95% CI 2.27-15.99) was independently associated with unfavorable outcomes. An unreactive EEG predicted unfavorable outcome with a specificity of 48% (95% CI 40-56), sensitivity of 79% (95% CI 72-85), and positive predictive value (PPV) of 74% (95% CI 67-81). Conversely, a benign EEG (defined as continuous and reactive background activity without seizure, periodic discharges, triphasic waves, or burst suppression) predicted favorable outcome with a specificity of 89% (95% CI 84-94), and a sensitivity of 37% (95% CI 30-45).

CONCLUSION

The absence of EEG reactivity independently predicts unfavorable outcomes at one year in severe stroke patients requiring mechanical ventilation in the ICU, although its prognostic value remains limited. Conversely, a benign EEG pattern was associated with a favorable outcome.

Factors contributing to sepsis-associated encephalopathy: a comprehensive systematic review and meta-analysis

Background

This study aims to systematically assess the risk factors, the overall strength of association, and evidence quality related to sepsis-associated encephalopathy.

Methods

A systematic search was conducted in the Cochrane Library, PubMed, Web of Science, and Embase for cohort or case-control studies published up to August 2023 on risk factors associated with sepsis-related encephalopathy. The selected studies were screened, data were extracted, and the quality was evaluated using the Newcastle-Ottawa Scale. Meta-analysis was performed using RevMan 5.3 software. The certainty of the evidence was assessed using the GRADE criteria.

Results

A total of 13 studies involving 1,906 participants were included in the analysis. Among these studies, 12 were of high quality, and one was of moderate quality. Our meta-analysis identified six risk factors significantly associated with Serious Adverse Events (SAE). These included APACHE II, SOFA, age, tau protein, and IL-6, which were found to be risk factors with significant effects (standard mean difference SMD: 1.24-2.30), and albumin, which was a risk factor with moderate effects (SMD: -0.55). However, the certainty of evidence for the risk factors identified in this meta-analysis ranged from low to medium.

Conclusion

This systematic review and meta-analysis identified several risk factors with moderate to significant effects. APACHE II, SOFA, age, tau protein, IL-6, and albumin were associated with sepsis-related encephalopathy and were supported by medium- to high-quality evidence. These findings provide healthcare professionals with an evidence-based foundation for managing and treating hospitalized adult patients with sepsis-related encephalopathy.

IL-1β, the first piece to the puzzle of sepsis-related cognitive impairment?

Sepsis is a leading cause of death resulting from an uncontrolled inflammatory response to an infectious agent. Multiple organ injuries, including brain injuries, are common in sepsis. The underlying mechanism of sepsis-associated encephalopathy (SAE), which is associated with neuroinflammation, is not yet fully understood. Recent studies suggest that the release of interleukin-1β (IL-1β) following activation of microglial cells plays a crucial role in the development of long-lasting neuroinflammation after the initial sepsis episode. This review provides a comprehensive analysis of the recent literature on the molecular signaling pathways involved in microglial cell activation and interleukin-1β release. It also explores the physiological and pathophysiological role of IL-1β in cognitive function, with a particular focus on its contribution to long-lasting neuroinflammation after sepsis. The findings from this review may assist healthcare providers in developing novel interventions against SAE.

Acute encephalopathy in the ICU: a practical approach

PURPOSE OF REVIEW

Acute encephalopathy (AE) - which frequently develops in critically ill patients with and without primary brain injury - is defined as an acute process that evolves rapidly and leads to changes in baseline cognitive status, ranging from delirium to coma. The diagnosis, monitoring, and management of AE is challenging. Here, we discuss advances in definitions, diagnostic approaches, therapeutic options, and implications to outcomes of the clinical spectrum of AE in ICU patients without primary brain injury.

RECENT FINDINGS

Understanding and definitions of delirium and coma have evolved. Delirium is a neurocognitive disorder involving impairment of attention and cognition, usually fluctuating, and developing over hours to days. Coma is a state of unresponsiveness, with absence of command following, intelligible speech, or visual pursuit, with no imaging or neurophysiological evidence of cognitive motor dissociation. The CAM-ICU(-7) and the ICDSC are validated, guideline-recommended tools for clinical delirium assessment, with identification of clinical subtypes and stratification of severity. In comatose patients, the roles of continuous EEG monitoring and neuroimaging have grown for the early detection of secondary brain injury and treatment of reversible causes.

SUMMARY

Evidence-based pharmacologic treatments for delirium are limited. Dexmedetomidine is effective for mechanically ventilated patients with delirium, while haloperidol has minimal effect of delirium but may have other benefits. Specific treatments for coma in nonprimary brain injury are still lacking.

Minocycline mitigated enduring neurological consequences in the mice model of sepsis

AIM

Sepsis-associated encephalopathy is a frequently observed consequence of sepsis, often resulting in chronic brain inflammation and injury, ultimately leading to a range of behavioral abnormalities. This study explores the potential preventive effects of minocycline on the long-lasting outcome of sepsis in a mice model of sepsis.

METHODS

Adult male C57 mice were subjected to experimental sepsis through a single intraperitoneal injection of 5 mg/kg lipopolysaccharide (LPS). Minocycline administration via oral gavage (12.5, 25, and 50 mg/kg) commenced three days before sepsis induction and continued on the day of induction. Mice underwent behavioral assessments one month post-sepsis, with subsequent brain tissue analysis to investigate oxidative stress markers and cholinergic function.

KEY FINDINGS

One month following sepsis induction, mice exhibited significant anxiety- and depressive-like behaviors as determined by assessments in the elevated plus maze (EPM), open field, and tail suspension test (TST). Additionally, they displayed impaired recognition memory in the novel object recognition (NOR) test. Brain tissue analysis revealed a notable increase in oxidative stress markers and acetylcholinesterase (AChE) activity in septic mice. Notably, minocycline treatment effectively mitigated the long-term behavioral abnormalities resulting from sepsis, attenuated oxidative stress markers, and reduced AChE activity.

SIGNIFICANCE

These findings underscore the potential of minocycline as a therapeutic intervention during sepsis induction to prevent the enduring behavioral and neurological consequences of experimental sepsis.

Ferroptosis-related exosomal non-coding RNAs: promising targets in pathogenesis and treatment of non-malignant diseases

Ferroptosis, an iron-dependent form of programmed cell death, introduces a novel perspective on cellular demise. This study investigates the regulatory network of exosomal non-coding RNAs (ncRNAs), including miRNAs, circRNAs, and lncRNAs, in ferroptosis modulation. The primary goal is to examine the pathological roles of ferroptosis-related exosomal ncRNAs, particularly in ischemic reperfusion injuries. The research reveals intricate molecular interactions governing the regulatory interplay between exosomal ncRNAs and ferroptosis, elucidating their diverse roles in different non-malignant pathological contexts. Attention is given to their impact on diseases, including cardiac, cerebral, liver, and kidney ischemic injuries, as well as lung, wound, and neuronal injuries. Beyond theoretical exploration, the study provides insights into potential therapeutic applications, emphasizing the significance of mesenchymal stem cells (MSCs)-derived exosomes. Findings underscore the pivotal role of MSC-derived exosomal ncRNAs in modulating cellular responses related to ferroptosis regulation, introducing a cutting-edge dimension. This recognition emphasizes the importance of MSC-derived exosomes as crucial mediators with broad therapeutic implications. Insights unveil promising avenues for targeted interventions, capitalizing on the diverse roles of exosomal ncRNAs, providing a comprehensive foundation for future therapeutic strategies.

Association of Sepsis With Neurologic Outcomes of Adult Patients Treated With Venoarterial Extracorporeal Membrane Oxygnenation

OBJECTIVES

Neurologic outcomes of patients under venoarterial extracorporeal membrane oxygenation (VA-ECMO) may be worsened by secondary insults of systemic origin. We aimed to assess whether sepsis, commonly observed during ECMO support, is associated with brain injury and outcomes.

DESIGN

Single-center cohort study of the "exposed-non-exposed" type on consecutive adult patients treated by VA-ECMO.

SETTING

Medical ICU of a university hospital, France, 2013-2020.

PATIENTS

Patients with sepsis at the time of VA-ECMO cannulation ("sepsis" group) were compared with patients without sepsis ("no sepsis" group). The primary outcome measure was poor functional outcome at 90 days, defined by a score greater than or equal to 4 on the modified Rankin scale (mRS), indicating severe disability or death.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 196 patients were included ("sepsis," n = 128; "no sepsis," n = 68), of whom 87 (44.4%) had presented cardiac arrest before VA-ECMO cannulation. A poor functional outcome (mRS ≥ 4) was observed in 99 of 128 patients (77.3%) of the "sepsis" group and 46 of 68 patients (67.6%) of the "no sepsis" group (adjusted logistic regression odds ratio (OR) 1.21, 95% CI, 0.58-2.47; inverse probability of treatment weighting (IPTW) OR 1.24; 95% CI, 0.79-1.95). Subsequent analyses performed according to pre-ECMO cardiac arrest status suggested that sepsis was independently associated with poorer functional outcomes in the subgroup of patients who had experienced pre-ECMO cardiac arrest (adjusted logistic regression OR 3.44; 95% CI, 1.06-11.40; IPTW OR 3.52; 95% CI, 1.68-7.73), whereas no such association was observed in patients without pre-ECMO cardiac arrest (adjusted logistic regression OR 0.69; 95% CI, 0.27-1.69; IPTW OR 0.76; 95% CI, 0.42-1.35). Compared with the "no sepsis" group, "sepsis" patients presented a significant increase in S100 calcium-binding protein beta concentrations at day 1 (0.94 μg/L vs. 0.52 μg/L, p = 0.03), and more frequent EEG alterations (i.e., severe slowing, discontinuous background, and a lower prevalence of sleep patterns), suggesting brain injury.

CONCLUSION

We observed a detrimental role of sepsis on neurologic outcomes in the subgroup of patients who had experienced pre-ECMO cardiac arrest, but not in other patients.