Traumatic brain injury: pathophysiology for neurocritical care

Sphingolipid changes in mouse brain and plasma after mild traumatic brain injury at the acute phases

BACKGROUND

Traumatic brain injury (TBI) causes neuroinflammation and can lead to long-term neurological dysfunction, even in cases of mild TBI (mTBI). Despite the substantial burden of this disease, the management of TBI is precluded by an incomplete understanding of its cellular mechanisms. Sphingolipids (SPL) and their metabolites have emerged as key orchestrators of biological processes related to tissue injury, neuroinflammation, and inflammation resolution. No study so far has investigated comprehensive sphingolipid profile changes immediately following TBI in animal models or human cases. In this study, sphingolipid metabolite composition was examined during the acute phases in brain tissue and plasma of mice following mTBI.

METHODS

Wildtype mice were exposed to air-blast-mediated mTBI, with blast exposure set at 50-psi on the left cranium and 0-psi designated as Sham. Sphingolipid profile was analyzed in brain tissue and plasma during the acute phases of 1, 3, and 7 days post-TBI via liquid-chromatography-mass spectrometry. Simultaneously, gene expression of sphingolipid metabolic markers within brain tissue was analyzed using quantitative reverse transcription-polymerase chain reaction. Significance (P-values) was determined by non-parametric t-test (Mann-Whitney test) and by Tukey's correction for multiple comparisons.

RESULTS

In post-TBI brain tissue, there was a significant elevation of 1) acid sphingomyelinase (aSMase) at 1- and 3-days, 2) neutral sphingomyelinase (nSMase) at 7-days, 3) ceramide-1-phosphate levels at 1 day, and 4) monohexosylceramide (MHC) and sphingosine at 7-days. Among individual species, the study found an increase in C18:0 and a decrease in C24:1 ceramides (Cer) at 1 day; an increase in C20:0 MHC at 3 days; decrease in MHC C18:0 and increase in MHC C24:1, sphingomyelins (SM) C18:0, and C24:0 at 7 days. Moreover, many sphingolipid metabolic genes were elevated at 1 day, followed by a reduction at 3 days and an absence at 7-days post-TBI. In post-TBI plasma, there was 1) a significant reduction in Cer and MHC C22:0, and an increase in MHC C16:0 at 1 day; 2) a very significant increase in long-chain Cer C24:1 accompanied by significant decreases in Cer C24:0 and C22:0 in MHC and SM at 3 days; and 3) a significant increase of C22:0 in all classes of SPL (Cer, MHC and SM) as well as a decrease in Cer C24:1, MHC C24:1 and MHC C24:0 at 7 days.

CONCLUSIONS

Alterations in sphingolipid metabolite composition, particularly sphingomyelinases and short-chain ceramides, may contribute to the induction and regulation of neuroinflammatory events in the early stages of TBI, suggesting potential targets for novel diagnostic, prognostic, and therapeutic strategies in the future.

Association of Postarrest Hypotension Burden With Unfavorable Neurologic Outcome After Pediatric Cardiac Arrest

OBJECTIVE

Quantify hypotension burden using high-resolution continuous arterial blood pressure (ABP) data and determine its association with outcome after pediatric cardiac arrest.

DESIGN

Retrospective observational study.

SETTING

Academic PICU.

PATIENTS

Children 18 years old or younger admitted with in-of-hospital or out-of-hospital cardiac arrest who had invasive ABP monitoring during postcardiac arrest care.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

High-resolution continuous ABP was analyzed up to 24 hours after the return of circulation (ROC). Hypotension burden was the time-normalized integral area between mean arterial pressure (MAP) and fifth percentile MAP for age. The primary outcome was unfavorable neurologic status (pediatric cerebral performance category ≥ 3 with change from baseline) at hospital discharge. Mann-Whitney U tests compared hypotension burden, duration, and magnitude between favorable and unfavorable patients. Multivariable logistic regression determined the association of unfavorable outcomes with hypotension burden, duration, and magnitude at various percentile thresholds from the 5th through 50th percentile for age. Of 140 patients (median age 53 [interquartile range 11-146] mo, 61% male); 63% had unfavorable outcomes. Monitoring duration was 21 (7-24) hours. Using a MAP threshold at the fifth percentile for age, the median hypotension burden was 0.01 (0-0.11) mm Hg-hours per hour, greater for patients with unfavorable compared with favorable outcomes (0 [0-0.02] vs. 0.02 [0-0.27] mm Hg-hr per hour, p < 0.001). Hypotension duration and magnitude were greater for unfavorable compared with favorable patients (0.03 [0-0.77] vs. 0.71 [0-5.01]%, p = 0.003; and 0.16 [0-1.99] vs. 2 [0-4.02] mm Hg, p = 0.001). On logistic regression, a 1-point increase in hypotension burden below the fifth percentile for age (equivalent to 1 mm Hg-hr of burden per hour of recording) was associated with increased odds of unfavorable outcome (adjusted odds ratio [aOR] 14.8; 95% CI, 1.1-200; p = 0.040). At MAP thresholds of 10th-50th percentiles for age, MAP burden below the threshold was greater in unfavorable compared with favorable patients in a dose-dependent manner.

CONCLUSIONS

High-resolution continuous ABP data can be used to quantify hypotension burden after pediatric cardiac arrest. The burden, duration, and magnitude of hypotension are associated with unfavorable neurologic outcomes.

Quantifying injury expansion in the cervical spinal cord with intravital ultrafast contrast-enhanced ultrasound imaging

Spinal cord injury is characterized by hemodynamic disruption at the injury epicenter and hypoperfusion in the penumbra, resulting in progressive ischemia and cell death. This degenerative secondary injury process has been well-described, though mostly using ex vivo or depth-limited optical imaging techniques. Intravital contrast-enhanced ultrasound enables longitudinal, quantitative evaluation of anatomical and hemodynamic changes in vivo through the entire spinal parenchyma. Here, we used ultrasound imaging to visualize and quantify subacute injury expansion (through 72 h post-injury) in a rodent cervical contusion model. Significant intraparenchymal hematoma expansion was observed through 72 h post-injury (1.86 ± 0.17-fold change from acute, p < 0.05), while the volume of the ischemic deficit largely increased within 24 h post-injury (2.24 ± 0.27-fold, p < 0.05). Histology corroborated these findings; increased apoptosis, tissue and vessel loss, and sustained tissue hypoxia were observed at 72 h post-injury. Vascular resistance was significantly elevated in the remaining perfused tissue, likely due in part to deformation of the central sulcal artery nearest to the lesion site. In conjunction, substantial hyperemia was observed in all perilesional areas examined except the ipsilesional gray matter. This study demonstrates the utility of longitudinal ultrasound imaging as a quantitative tool for tracking injury progression in vivo.

Cardiac Injury After Traumatic Brain Injury: Clinical Consequences and Management

Traumatic brain injury (TBI) is a significant public health issue because of its increasing incidence and the substantial short-term and long-term burden it imposes. This burden includes high mortality rates, morbidity, and a significant impact on productivity and quality of life for survivors. During the management of TBI, extracranial complications commonly arise during the patient's stay in the intensive care unit. These complications can have an impact on both mortality and the neurological outcome of patients with TBI. Among these extracranial complications, cardiac injury is a relatively frequent occurrence, affecting approximately 25-35% of patients with TBI. The pathophysiology underlying cardiac injury in TBI involves the intricate interplay between the brain and the heart. Acute brain injury triggers a systemic inflammatory response and a surge of catecholamines, leading to the release of neurotransmitters and cytokines. These substances have detrimental effects on the brain and peripheral organs, creating a vicious cycle that exacerbates brain damage and cellular dysfunction. The most common manifestation of cardiac injury in TBI is corrected QT (QTc) prolongation and supraventricular arrhythmias, with a prevalence up to 5 to 10 times higher than in the general adult population. Other forms of cardiac injury, such as regional wall motion alteration, troponin elevation, myocardial stunning, or Takotsubo cardiomyopathy, have also been described. In this context, the use of β-blockers has shown potential benefits by intervening in this maladaptive process. β-blockers can limit the pathological effects on cardiac rhythm, blood circulation, and cerebral metabolism. They may also mitigate metabolic acidosis and potentially contribute to improved cerebral perfusion. However, further clinical studies are needed to elucidate the role of new therapeutic strategies in limiting cardiac dysfunction in patients with severe TBI.

Trending Ability of End-Tidal Capnography Monitoring During Mechanical Ventilation to Track Changes in Arterial Partial Pressure of Carbon Dioxide in Critically Ill Patients With Acute Brain Injury: A Monocenter Retrospective Study

BACKGROUND

Changes in arterial partial pressure of carbon dioxide (Pa co2 ) may alter cerebral perfusion in critically ill patients with acute brain injury. Consequently, international guidelines recommend normocapnia in mechanically ventilated patients with acute brain injury. The measurement of end-tidal capnography (Et co2 ) allows its approximation. Our objective was to report the agreement between trends in Et co2 and Pa co2 during mechanical ventilation in patients with acute brain injury.

METHODS

Retrospective monocenter study was conducted for 2 years. Critically ill patients with acute brain injury who required mechanical ventilation with continuous Et co2 monitoring and with 2 or more arterial gas were included. The agreement was evaluated according to the Bland and Altman analysis for repeated measurements with calculation of bias, and upper and lower limits of agreement. The directional concordance rate of changes between Et co2 and Pa co2 was evaluated with a 4-quadrant plot. A polar plot analysis was performed using the Critchley methods.

RESULTS

We analyzed the data of 255 patients with a total of 3923 paired ΔEt co2 and ΔPa co2 (9 values per patient in median). Mean bias by Bland and Altman analysis was -8.1 (95 CI, -7.9 to -8.3) mm Hg. The directional concordance rate between Et co2 and Pa co2 was 55.8%. The mean radial bias by polar plot analysis was -4.4° (95% CI, -5.5 to -3.3) with radial limit of agreement (LOA) of ±62.8° with radial LOA 95% CI of ±1.9°.

CONCLUSIONS

Our results question the performance of trending ability of Et co2 to track changes in Pa co2 in a population of critically ill patients with acute brain injury. Changes in Et co2 largely failed to follow changes in Pa co2 in both direction (ie, low concordance rate) and magnitude (ie, large radial LOA). These results need to be confirmed in prospective studies to minimize the risk of bias.

From bedside to recovery: exercise therapy for prevention of post-intensive care syndrome

BACKGROUND

As advancements in critical care medicine continue to improve Intensive Care Unit (ICU) survival rates, clinical and research attention is urgently shifting toward improving the quality of survival. Post-Intensive Care Syndrome (PICS) is a complex constellation of physical, cognitive, and mental dysfunctions that severely impact patients' lives after hospital discharge. This review provides a comprehensive and multi-dimensional summary of the current evidence and practice of exercise therapy (ET) during and after an ICU admission to prevent and manage the various domains of PICS. The review aims to elucidate the evidence of the mechanisms and effects of ET in ICU rehabilitation and highlight that suboptimal clinical and functional outcomes of ICU patients is a growing public health concern that needs to be urgently addressed.

MAIN BODY

This review commences with a brief overview of the current relationship between PICS and ET, describing the latest research on this topic. It subsequently summarises the use of ET in ICU, hospital wards, and post-hospital discharge, illuminating the problematic transition between these settings. The following chapters focus on the effects of ET on physical, cognitive, and mental function, detailing the multi-faceted biological and pathophysiological mechanisms of dysfunctions and the benefits of ET in all three domains. This is followed by a chapter focusing on co-interventions and how to maximise and enhance the effect of ET, outlining practical strategies for how to optimise the effectiveness of ET. The review next describes several emerging technologies that have been introduced/suggested to augment and support the provision of ET during and after ICU admission. Lastly, the review discusses future research directions.

CONCLUSION

PICS is a growing global healthcare concern. This review aims to guide clinicians, researchers, policymakers, and healthcare providers in utilising ET as a therapeutic and preventive measure for patients during and after an ICU admission to address this problem. An improved understanding of the effectiveness of ET and the clinical and research gaps that needs to be urgently addressed will greatly assist clinicians in their efforts to rehabilitate ICU survivors, improving patients' quality of survival and helping them return to their normal lives after hospital discharge.

Network pharmacology and molecular docking-based investigation of monocyte locomotion inhibitory factor attenuates traumatic brain injury by regulating aquaporin 4 expression

Traumatic brain injury (TBI) is a significant cause of disability and mortality worldwide, and effective treatment options are currently limited. Monocyte locomotion inhibitor factor (MLIF), a small molecular pentapeptide, has demonstrated a protective effect against cerebral ischemia. This study aimed to investigate the protective effects of MLIF on TBI and explore its underlying mechanism of action. In animal experiments, we observed that administration of MLIF after TBI reduced brain water content and improved brain edema, suggesting a certain degree of protection against TBI. By utilizing network pharmacology methodologies, we employed target screening techniques to identify the potential targets of MLIF in the context of TBI. As a result, we successfully enriched ten signaling pathways that are closely associated with TBI. Furthermore, using molecular docking techniques, we identified AQP4 as one of the top ten central genes discovered in this study. Eventually, our study demonstrated that MLIF exhibits anti-apoptotic properties and suppresses the expression of AQP4 protein, thus playing a protective role in traumatic brain injury. This conclusion was supported by TUNEL staining and the evaluation of Bcl-2, Bax, and AQP4 protein levels. These discoveries enhance our comprehension of the mechanisms by which MLIF exerts its protective effects and highlight its potential as a promising therapeutic intervention for TBI treatment.

Brain Regional Energy Metabolism in Patients with Traumatic Brain Injury: A Cerebral Microdialysis Guided Study

BACKGROUND

In traumatic brain injuries (TBI), cerebral microdialysis (CMD)-derived parameters, especially the lactate to pyruvate ratio (LP ratio), have been utilized for cerebral perfusion optimization. The objectives were to identify cerebral ischemia as measured by CMD in TBI patients requiring decompressive craniectomy and to observe the correlation between cerebral perfusion pressure (CPP), intracranial pressure (ICP), and CMD variables in these patients. Our secondary aim was to observe the effect of CPP augmentation on ischemia biomarkers.

METHODS

After the Institute Ethics Committee approvals, seven adult patients requiring decompressive craniectomy following TBI were enrolled and CMD data were obtained prospectively for 72 h. CPP was augmented by 20% with noradrenaline infusion if LP ratio >40. Correlations were done with bootstrapping (n = 500) to obtain the confidence intervals (CI) due to the small sample size.

RESULTS

One patient had cerebral ischemia (median LP ratio of 265.5 and median pyruvate of 38 μmol/L), while another patient had non-ischemic mitochondrial dysfunction (median LP ratio 40.7 and median pyruvate 278.5). The coefficients of correlation between the LP ratio with CPP and ICP were r = -0.05 (CI = -0.14-0.03) and r = 0.09 (CI = -0.03-0.24), respectively. The coefficient of correlation between cerebral and blood glucose was r = 0.38, (CI - 0.35-0.14). Only two patients needed CPP augmentation, however, postaugmentation cerebral biochemistry did not change appreciably.

CONCLUSION

CMD can identify cerebral ischemia, however, no correlations were observed between the LP ratio and CPP or ICP. CPP augmentation did not improve cerebral biochemistry. More studies are required to understand and treat cerebral metabolism in TBI.

CLINICAL VALUE OF SYNDECAN-1 LEVELS IN TRAUMA BRAIN INJURY: A META-ANALYSIS

ABSTRACT

Background: Traumatic brain injury (TBI) is a head trauma usually associated with death and endothelial glycocalyx damage. Syndecan-1 (SDC-1)-a biomarker of glycocalyx degradation-has rarely been reported in meta-analyses to determine the clinical prognostic value in TBI patients. Methods: We looked into PubMed, EMBASE, Cochrane Library, and Web of Science databases from January 1, 1990, to May 1, 2023, to identify eligible studies. A meta-analysis was conducted using RevMan 5.4 and Stata 16.0 with the search terms "SDC-1" and "traumatic brain injury." Results: The present study included five studies with a total of 640 enrolled patients included. Syndecan-1 concentrations were higher in the isotrauma TBI group than in the non-TBI group (standardized mean difference [SMD] = 0.52; 95% CI: 0.03-1.00; P = 0.04). Subgroup analysis revealed statistical significance when comparing the SDC-1 level of multitrauma TBI (TBI + other injuries) group with the isotrauma TBI group (SMD = 0.74; 95% CI: 0.42-1.05; P < 0.001), and the SDC-1 level of the TBI coagulopathy (+) group (TBI with early coagulopathy) with the TBI coagulopathy (-) group (SMD = 1.75; 95% CI: 0.41-3.10; P = 0.01). Isotrauma TBI patients with higher SDC-1 level were at a higher risk of 30-day in-hospital mortality (odds ratio = 3.32; 95% CI: 1.67-6.60; P = 0.0006). Conclusion: This meta-analysis suggests that SDC-1 could be a biomarker of endotheliopathy and coagulopathy in TBI, as it was increased in isotrauma TBI patients and was higher in multitrauma TBI patients. There is a need for additional research into the use of SDC-1 as a prognostic biomarker in TBI, especially in isotrauma TBI patients.

Can Neutrophil to Lymphocyte Ratio Predict Early Outcome in Patients with Spinal Cord Injury?

BACKGROUND

Spinal cord injury is a frequent debilitating neurologic condition with increasing prevalence and related morbidity over the last decades. The neutrophil-to-lymphocyte ratio is a promising biomarker for determining different medical conditions' disease course and outcome such as traumatic brain injury (TBI). This study aimed to investigate the predictive value of neutrophil to lymphocyte ratio (NLR) in the outcome of SCI.

METHOD

In a retrospective cross-sectional study from April 2019 to April 2022, all patients 18 to 65 years old, following spinal cord injury who were referred to Imam Khomeini Hospital and met inclusion and exclusion criteria enrolled in the study. A checklist including demographic data, lab, and clinical findings at admission, 24h, 48 h, and discharge were recorded. IBM SPSS Statistics software was used to analyze the data. A P-value of less than 0.05 was considered significant.

RESULTS

Six hundred patients met our inclusion criteria and enrolled in the study. The mean age of the patients was 40.93 ± 12.77, with 75% male and 25% female. There was a significant correlation between the N/L ratio at different time points (p.value=0.001), injury type, and ASIA score at admission and discharge (0.001). Furthermore, the NLR had approached significant value alone to predict outcomes in patients enrolled in the study (0.06).

CONCLUSIONS

A high NLR is unequivocally linked with poor outcomes in patients suffering from acute SCI and should be considered a negative prognostic factor; however, the NLR had approached significant predicting value in patients enrolled in the study.

Evidence-based management of adult traumatic brain injury with raised intracranial pressure in intensive critical care unit at resource-limited settings: a literature review

Background

In underdeveloped countries, there is a greater incidence of mortality and morbidity arising from trauma, with traumatic brain injury (TBI) accounting for 50% of all trauma-related deaths. The occurrence of elevated intracranial pressure (ICP), which is a common pathophysiological phenomenon in cases of TBI, acts as a contributing factor to unfavorable outcomes. The aim of this systematic review is to analyze the existing literature regarding the management of adult TBI with raised ICP in an intensive critical care unit, despite limited resources.

Methods

This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis protocol. Search engines such as PubMed, the Cochrane database, and Google Scholar were utilized to locate high-level evidence that would facilitate the formation of sound conclusions.

Result

A total of 11 715 articles were identified and individually assessed to determine their eligibility for inclusion or exclusion based on predetermined criteria and outcome variables. The methodological quality of each study was evaluated using recommended criteria. Ultimately, the review consisted of 51 articles.

Conclusion

Physical examination results and noninvasive assessments of the optic nerve sheath diameter (ONSD) via sonography are positively associated with elevated ICP, and are employed as diagnostic and monitoring tools for elevated ICP in resource-limited settings. Management of elevated ICP necessitates an algorithmic approach that utilizes prophylactic measures and acute intervention treatments to mitigate the risk of secondary brain injury.

Guidelines for Prehospital Management of Traumatic Brain Injury 3rd Edition: Executive Summary

Prehospital care markedly influences outcome from traumatic brain injury, yet it remains highly variable. The Brain Trauma Foundation's guidelines informing prehospital care, first published in 2002, have sought to identify and disseminate best practices. Many of its recommendations relate to the management of airway, breathing and circulation, and infrastructure for this care. Compliance with the second edition of these guidelines has been associated with significantly improved survival. A working group developed evidence-based recommendations informing assessment, treatment, and transport decision-making relevant to the prehospital care of brain injured patients. A literature search spanning May 2005 to January 2022 supplemented data contained in the 2nd edition. Identified studies were assessed for quality and used to inform evidence-based recommendations. A total of 122 published articles formed the evidentiary base for this guideline update including 5 providing Class I evidence, 35 providing Class II evidence, and 98 providing Class III evidence for the various topics. Forty evidence-based recommendations were generated, 30 of which were strong and 10 of which were weak. In many cases, new evidence allowed guidelines from the 2nd edition to be strengthened. Development of guidelines on some new topics was possible including the prehospital administration of tranexamic acid. A management algorithm is also presented. These guidelines help to identify best practices for prehospital traumatic brain injury care, and they also identify gaps in knowledge which we hope will be addressed before the next edition.

Elevation of White Blood Cell Subtypes in Adult Trauma Patients with Stress-Induced Hyperglycemia

BACKGROUND

Blood immune cell subset alterations following trauma can indicate a patient's immune-inflammatory status. This research explored the influence of stress-induced hyperglycemia (SIH) on platelet counts and white blood cell (WBC) subtypes, including the derived indices of the monocyte-to-lymphocyte ratio (MLR), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR), in trauma patients.

METHODS

We studied 15,480 adult trauma patients admitted from 1 January 1998 to 31 December 2022. They were categorized into four groups: nondiabetic normoglycemia (NDN, n = 11,602), diabetic normoglycemia (DN, n = 1750), SIH (n = 716), and diabetic hyperglycemia (DH, n = 1412). A propensity score-matched cohort was formed after adjusting for age, sex, and comorbidities, allowing for comparing the WBC subtypes and platelet counts.

RESULTS

Patients with SIH exhibited significantly increased counts of monocytes, neutrophils, and lymphocytes in contrast to NDN patients. However, no significant rise in platelet counts was noted in the SIH group. There were no observed increases in these cell counts in either the DN or DH groups.

CONCLUSIONS

Our results demonstrated that trauma patients with SIH showed significantly higher counts of monocytes, neutrophils, and lymphocytes when compared to NDN patients, whereas the DN and DH groups remained unaffected. This underscores the profound association between SIH and elevated levels of specific WBC subtypes.

Hyperemia in head injury: can transcranial doppler help to personalize therapies for intracranial hypertension?

Introduction

An increase in cerebral blood flow is frequent after traumatic brain injury (TBI) and can lead to brain swelling and refractory intracranial hypertension. We hypothesized that Transcranial EcoDoppler (TCD) monitoring could be useful to detect the cause of intracranial hypertension in these patients. Our main objective was to investigate if the increase of velocity in the middle cerebral artery (MCA) on TCD could be associated with intracranial hypertension.

Methods

We retrospectively studied TBI patients consecutively monitored with TCD. Hyperemia was defined as MCA mean velocity higher than 80 cm/s. Intracranial hypertension was considered when hyperosmolar therapy, hyperventilation, or deep sedation was used.

Results

We found hyperemia in 40 patients out of 118 (33.9%). On average, it started at day 2.1 ± 0.9 from admission and significantly increased (MCA velocity at day 1: 74 ± 25 cm/s vs. 109 ± 36 cm/s at day 4; p < 0.001). Intracranial hypertension was significantly associated with hyperemia, occurring in 92.5% of hyperemic and 51.3% of non-hyperemic patients (p < 0.001). Moreover, we found that hyperemia preceded severe intracranial hypertension (p < 0.0001). In a logistic regression model, hyperemia was the only variable significantly correlated with intracranial hypertension (OR 10.64; p < 0.001).

Discussion

Hyperemia was frequent in our population of TBI patients and preceded intracranial hypertension. TCD monitoring, if performed on a daily regular basis, can be a useful method to detect this phenomenon and to guide the therapy. It could be a tool for a cause-oriented therapy of intracranial hypertension.

Targeted temperature management and PbtO2 in traumatic brain injury

Introduction

Targeted Temperature Management (TTM) to normothermia is widely used in traumatic brain injury (TBI). We investigated the effects to of TTM to normothermia patients with TBI (GCS≤12) monitored with multimodality monitoring, to better understand the physiological consequences of this intervention.

Research question

In TBI patients cooled to normothermia and in which brain oxygenation deteriorates, are there changes in physiological parameters which are pertinent to brain oxygenation?

Material and method

102 TBI patients with continuous recordings of intracranial pressure (ICP) and brain oxygen tension (PbtO2) were studied retrospectively. Non-continuous arterial carbon dioxide (PaCO2) and oxygen (PaO2) tensions, and core body temperature (Tc) were added. PaO2 and PaCO2 were also corrected for Tc. Transitions from elevated Tc to normothermia were identified in 39 patients. The 8 h pre and post the transition to normothermia were compared. Data is given as median [IQR] or mean (SD).

Results

Overall, normothermia reduced ICP (12 [9-18] -11 [8-17] mmHg, p < 0.009) and Tcore (38.3 [0.3]-36.9 [0.4] oC, p < 0.001), but not PbtO2 (23.3 [16.6]-24.4 [17.2-28.7] mmHg, NS). Normothermia was associated with a fall in PbtO2 in 18 patients (24.5 [9.3] -20.8 [7.6] mmHg). Only in those with a fall in PbtO2 with cooling did ICP (15 [10.8-18.5] -12 [7.8-17.3] mmHg, p = 0.002), and temperature corrected PaCO2 (5.3 [0.5]- 4.9 [0.8] kPa, p = 0.001) decrease.

Discussion and conclusion

A reduction in PbtO2 was only present in the subgroup of patients with a fall in temperature corrected PaCO2 with cooling. This suggests that even modest temperature changes could result in occult hyperventilation in some patients. pH stat correction of ventilation may be an important factor to consider in future TTM protocols.

Regulation of microglial responses after pediatric traumatic brain injury: exploring the role of SHIP-1

Introduction

Severe traumatic brain injury (TBI) is the world's leading cause of permanent neurological disability in children. TBI-induced neurological deficits may be driven by neuroinflammation post-injury. Abnormal activity of SH2 domain-containing inositol 5' phosphatase-1 (SHIP-1) has been associated with dysregulated immunological responses, but the role of SHIP-1 in the brain remains unclear. The current study investigated the immunoregulatory role of SHIP-1 in a mouse model of moderate-severe pediatric TBI.

Methods

SHIP-1+/- and SHIP-1-/- mice underwent experimental TBI or sham surgery at post-natal day 21. Brain gene expression was examined across a time course, and immunofluorescence staining was evaluated to determine cellular immune responses, alongside peripheral serum cytokine levels by immunoassays. Brain tissue volume loss was measured using volumetric analysis, and behavior changes both acutely and chronically post-injury.

Results

Acutely, inflammatory gene expression was elevated in the injured cortex alongside increased IBA-1 expression and altered microglial morphology; but to a similar extent in SHIP-1-/- mice and littermate SHIP-1+/- control mice. Similarly, the infiltration and activation of CD68-positive macrophages, and reactivity of GFAP-positive astrocytes, was increased after TBI but comparable between genotypes. TBI increased anxiety-like behavior acutely, whereas SHIP-1 deficiency alone reduced general locomotor activity. Chronically, at 12-weeks post-TBI, SHIP-1-/- mice exhibited reduced body weight and increased circulating cytokines. Pro-inflammatory gene expression in the injured hippocampus was also elevated in SHIP-1-/- mice; however, GFAP immunoreactivity at the injury site in TBI mice was lower. TBI induced a comparable loss of cortical and hippocampal tissue in both genotypes, while SHIP-1-/- mice showed reduced general activity and impaired working memory, independent of TBI.

Conclusion

Together, evidence does not support SHIP-1 as an essential regulator of brain microglial morphology, brain immune responses, or the extent of tissue damage after moderate-severe pediatric TBI in mice. However, our data suggest that reduced SHIP-1 activity induces a greater inflammatory response in the hippocampus chronically post-TBI, warranting further investigation.

Recent Advancements and Strategies for Overcoming the Blood-Brain Barrier Using Albumin-Based Drug Delivery Systems to Treat Brain Cancer, with a Focus on Glioblastoma

Glioblastoma multiforme (GBM) is a highly aggressive malignant tumor, and the most prevalent primary malignant tumor affecting the brain and central nervous system. Recent research indicates that the genetic profile of GBM makes it resistant to drugs and radiation. However, the main obstacle in treating GBM is transporting drugs through the blood-brain barrier (BBB). Albumin is a versatile biomaterial for the synthesis of nanoparticles. The efficiency of albumin-based delivery systems is determined by their ability to improve tumor targeting and accumulation. In this review, we will discuss the prevalence of human glioblastoma and the currently adopted treatment, as well as the structure and some essential functions of the BBB, to transport drugs through this barrier. We will also mention some aspects related to the blood-tumor brain barrier (BTBB) that lead to poor treatment efficacy. The properties and structure of serum albumin were highlighted, such as its role in targeting brain tumors, as well as the progress made until now regarding the techniques for obtaining albumin nanoparticles and their functionalization, in order to overcome the BBB and treat cancer, especially human glioblastoma. The albumin drug delivery nanosystems mentioned in this paper have improved properties and can overcome the BBB to target brain tumors.

Intracranial Pressure and Brain Tissue Oxygen Multimodality Neuromonitoring in Gunshot Wounds to the Head in Children

OBJECTIVE

Gunshot wounds to the head (GSWH) are a cause of severe penetrating traumatic brain injury (TBI). Although multimodal neuromonitoring has been increasingly used in blunt pediatric TBI, its role in the pediatric population with GSWH is not known. We report on 3 patients who received multimodal neuromonitoring as part of clinical management at our institution and review the existing literature on pediatric GSWH.

METHODS

We identified 3 patients ≤18 years of age who were admitted to a quaternary children's hospital from 2005 to 2021 with GSWH and received invasive intracranial pressure (ICP) and Pbto2 (brain tissue oxygenation) monitoring with or without noninvasive near-infrared spectroscopy (NIRS). We analyzed clinical and demographic characteristics, imaging findings, and ICP, Pbto2, cerebral perfusion pressure, and rSo2 (regional cerebral oxygen saturation) NIRS trends.

RESULTS

All patients were male with an average admission Glasgow Coma Scale score of 4. One patient received additional NIRS monitoring. Episodes of intracranial hypertension (ICP ≥20 mm Hg) and brain tissue hypoxia (Pbto2 <15 mm Hg) or hyperemia (Pbto2 >35 mm Hg) frequently occurred independently of each other, requiring unique targeted treatments. rSo2 did not consistently mirror Pbto2. All children survived, with favorable Glasgow Outcome Scale-Extended score at 6 months after injury.

CONCLUSIONS

Use of ICP and Pbto2 multimodality neuromonitoring enabled specific management for intracranial hypertension or brain tissue hypoxia episodes that occurred independently of one another. Multimodality neuromonitoring has not been studied extensively in pediatric GSWH; however, its use may provide a more complete picture of patient injury and prognosis without significant added procedural risk.

Gastrointestinal Motility Disorders Correlate with Intracranial Bleeding, Opioid Use, and Brainstem Edema in Neurosurgical Patients

BACKGROUND

Gastrointestinal (GI) motility disorders may be directly associated with the intensity of acute brain injury, edema of the brainstem, and opioid use in neurosurgical patients.

METHODS

In this retrospective study, patient demographic characteristics, computed tomography (CT) scans, the occurrence of gastroparesis, constipation, and opioid use were registered during the intensive care unit (ICU) stay and correlated with days of mechanical ventilation, length of ICU stay, and survival. Gastroparesis was defined as residual gastric volume > 250 mL per day, and constipation was defined as the absence of stool for 3 days or more during the ICU stay.

RESULTS

Of 207 neurosurgical patients screened, 69 adult patients who spent more than 4 days in the ICU were included in the study. Gastroparesis was observed in 48 (69.6%) patients, constipation was observed in 67 (97.1%) patients, and stress ulcers were observed in 4 (5.8%) patients. Patients with brainstem edema (n = 57, 82.6%) had the first stool evacuation later compared with patients with no edema (8 [interquartile range (IQR) 5.25-9.75] vs. 3.5 [IQR 2.25-4] days; P < 0.001). In the logistic regression analysis, factors that were associated with GI dysmotility were central nervous system (CNS) bleeding (odds ratio [OR] 5.1, 95% confidence interval [CI] 1.26-20.8, P = 0.02), opioid use > 19.3 morphine equivalents (ME) per day (OR 5.37, 95% CI 1.1-27.1, P = 0.04), and brainstem edema (OR 4.9, 95% CI 1.1-21.6, P = 0.04). A receiver operating characteristic curve analysis confirmed that the cutoff value of > 6.78 ME per day was a good predictor determining GI dysmotility, with 89.5% sensitivity and 72.7% specificity (95% CI 0.67-0.88, area under the curve 0.784, Youden index 0.62, P = 0.001). Poor survival correlated with lower Glasgow Coma Score values (ρ =  - 520, P < 0.001), CNS bleeding (ρ = 0.393, P < 0.001), associated cardiac diseases (ρ = 0.279, P < 0.001), and cardiorespiratory arrest on admission (ρ = 0.315, P < 0.001), but not with GI dysmotility (ρ = 0.175, P = 0.402).

CONCLUSIONS

Significant correlation was registered between brainstem edema, gastrointestinal dysmotility, and opioids. CNS bleeding was the most important single factor influencing GI dysmotility. Further studies with opioid and nonopioid sedation may distinguish the influence of acute brain lesions versus drugs on GI dysmotility.

Identifying the Target Traumatic Brain Injury Population for Hyperbaric Oxygen Therapy

Traumatic brain injury (TBI) results from direct penetrating and indirect non-penetrating forces that alters brain functions, affecting millions of individuals annually. Primary injury following TBI is exacerbated by secondary brain injury; foremost is the deleterious inflammatory response. One therapeutic intervention being increasingly explored for TBI is hyperbaric oxygen therapy (HBOT), which is already approved clinically for treating open wounds. HBOT consists of 100% oxygen administration, usually between 1.5 and 3 atm and has been found to increase brain oxygenation levels after hypoxia in addition to decreasing levels of inflammation, apoptosis, intracranial pressure, and edema, reducing subsequent secondary injury. The following review examines recent preclinical and clinical studies on HBOT in the context of TBI with a focus on contributing mechanisms and clinical potential. Several preclinical studies have identified pathways, such as TLR4/NF-kB, that are affected by HBOT and contribute to its therapeutic effect. Thus far, the mechanisms mediating HBOT treatment have yet to be fully elucidated and are of interest to researchers. Nonetheless, multiple clinical studies presented in this review have examined the safety of HBOT and demonstrated the improved neurological function of TBI patients after HBOT, deeming it a promising avenue for treatment.

Correlating Intracranial Pressure Following Decompressive Craniectomy With Neurological Outcomes in Severe Traumatic Brain Injury Patients: A Prospective Observational Study

Introduction Decompressive craniectomies have been performed in settings with raised intracranial pressure (ICP) after severe traumatic brain injury (TBI). A decompressive craniectomy (DC) is an important salvage procedure for intracranial hypertension. The changes in the intracranial microenvironment after a primary DC are significant in terms of the neurological outcome in the postoperative period. Materials and methods The study comprised 68 patients with severe TBIs who were undergoing primary DC; of these, 59% were male. Recorded data include demographic profiles, clinical features, and cranial computed tomography (CT) scans. All patients underwent a primary unilateral DC with augmentation duraplasty. Intracranial pressure was recorded in the first 24 hours at regular intervals, and the outcome was recorded using the Extended Glasgow Outcome Scale (GOS-E) at two-week and two-month intervals. Results Road traffic accidents (RTAs) are the most common cause of severe TBIs. Imaging studies and intraoperative findings suggest that acute subdural hematomas (SDHs) are the most common pathology leading to high ICP in the postoperative period. Mortality was strongly statistically associated with high ICP values postoperatively at all intervals. The average ICP for the patients who died was 11.871 mmHg higher than the patients who survived (p=0.0009). The Glasgow Coma Scale (GCS) at the time of admission is positively correlated with the neurological outcome at two weeks and two months, with a Pearson correlation coefficient of 0.4190 and 0.4235, respectively. There is a strong negative correlation between ICP in the postoperative period and the neurological outcome at two weeks and two months (Pearson correlation coefficients are -0.828 and -0.841, respectively). Conclusion The results indicate that RTAs are the most common cause of severe TBIs, and acute SDHs are the most common pathology leading to high ICP after the surgery. ICP values in the postoperative period have a strong negative correlation with survival and neurological outcome. Preoperative GCS and postoperative ICP monitoring are important methods of prognostication and planning further management.

Effects of apolipoprotein E polymorphism on cerebral oxygen saturation, cerebral perfusion, and early prognosis after traumatic brain injury

OBJECTIVE

To investigate the effects of the apolipoprotein E (APOE) gene on oxygen saturation and cerebral perfusion in the early stages of traumatic brain injury (TBI).

METHODS

This study included 136 consecutive TBI patients and 51 healthy individuals. The APOE genotypes of all subjects were determined using quantitative fluorescence polymerase chain reaction (QF-PCR). Regional cerebral oxygen saturation (rScO2) of patients with TBI and normal subjects was monitored using near-infrared spectroscopy (NIRS). Computed tomography (CT) perfusion was used to obtain cerebral perfusion in patients with TBI and normal subjects.

RESULTS

In the TBI group, the rScO2 of APOEε4 carriers (53.06 ± 6.87%) was significantly lower than that of non-carriers (58.19 ± 5.83%, p < 0.05). Meanwhile, the MTT of APOEε4 carriers (6.75 ± 1.30 s) was significantly longer than that of non-carriers (5.87 ± 1.00 s, p < 0.05). Furthermore, correlation analysis showed a negative correlation between rSCO2 and MTT in patients with TBI. Both the univariate and multifactorial logistic regression analyses revealed that APOE ε4, hypoxia, MTT >5.75 s, Marshall CT Class, and GCS were independent risk factors for early poor prognosis in patients with TBI.

CONCLUSION

Both cerebral perfusion and cerebral oxygen were significantly impaired after TBI, and low cerebral perfusion and hypoxia were related to poor prognosis of patients with TBI. Compared with APOE ε4 non-carriers, APOE ε4 carriers not only had poorer cerebral perfusion and cerebral oxygen metabolism but also worse prognosis in the early stages of TBI. Furthermore, a negative correlation was observed between the rSCO2 and MTT levels. In addition, both CT perfusion scanning (CTP) and NIRS are reliable for monitoring the condition of patients with TBI in the neurological intensive care unit (NICU).

Incidence and predictors of mortality among traumatic brain injury patients admitted to Amhara region Comprehensive Specialized Hospitals, northwest Ethiopia, 2022

INTRODUCTION

Traumatic brain injury is a substantial cause of mortality and morbidity with a higher burden in low and middle-income countries due to healthcare systems that are unable to deliver effectively the acute and long-term care the patients require. Besides its burden, there is little information on traumatic brain injury-related mortality in Ethiopia, especially in the region. Therefore, this study aimed to assess the incidence and predictors of mortality among traumatic brain injury patients admitted to comprehensive specialized hospitals in the Amhara region, northwest Ethiopia, 2022.

METHODS

An institution-based retrospective follow-up study was conducted among 544 traumatic brain injury patients admitted from January 1, 2021, to December 31, 2021. A simple random sampling method was used. Data were extracted using a pre-tested and structured data abstraction sheet. Data were entered, coded, and cleaned into EPi-info version 7.2.0.1 software and exported to STATA version 14.1 for analysis. The Weibull regression model was fitted to determine the association between time to death and covariates. Variables with a P-value < 0.05 were declared statistically significant.

RESULTS

The overall incidence of mortality among traumatic brain injury patients was 1.23 per 100 person-day observation [95% (CI: 1.0, 1.5)] with a median survival time of 106 (95% CI: 60, 121) days. Age [AHR: 1.08 (95% CI; 1.06, 1.1)], severe traumatic brain injury [AHR: 10 (95% CI; 3.55, 28.2)], moderate traumatic brain injury [AHR: 9.2 (95% CI 2.97, 29)], hypotension [AHR: 6.9 (95% CI; 2.8, 17.1)], coagulopathy [AHR: 2.55 (95% CI: 1.27, 5.1)], hyperthermia [AHR: 2.79 (95% CI; 1.4, 5.5)], and hyperglycemia [AHR: 2.28 (95% CI; 1.13, 4.6)] were positively associated with mortality while undergoing neurosurgery were negatively associated with mortality [AHR: 0.47 (95% CI; 0.27-0 0.82)].

CONCLUSION

The overall incidence of mortality was found to be high. Age, severe and moderate traumatic brain injury, hypotension at admission, coagulopathy, presence of associated aspiration pneumonia, undergoing a neurosurgical procedure, episode of hyperthermia, and hyperglycemia during hospitalization were the independent predictors of time to death. Therefore, interventions to reduce mortality should focus on the prevention of primary injury and secondary brain injury.

Predictors of Social Participation Outcome after Traumatic Brain Injury Differ According to Rehabilitation Pathways

Social participation (SP) is one of many objectives in the rehabilitation of patients with traumatic brain injury (TBI). Studies on predictors of SP specific to post-acute universally accessible specialized rehabilitation pathways following TBI are scarce. Our objectives were to: 1) characterize SP, as well as a set of pre-injury, injury-related, and post-injury variables in individuals participating in inpatient-outpatient or outpatient rehabilitation pathways within a universally accessible and organized trauma continuum of care; and 2) examine the ability of pre-injury, injury-related, and post-injury variables in predicting SP outcome after TBI according to rehabilitation path. Participants (N = 372) were adults admitted to an inpatient-outpatient rehabilitation pathway or an outpatient rehabilitation pathway after sustaining a TBI between 2016 and 2020, and for whom Mayo-Portland Adaptability Intentory-4 (MPAI-4) outcomes were prospectively obtained at the start and end of rehabilitation. Additional data was collected from medical files. For both rehabilitation pathways, predicted SP outcome was MPAI-4 Participation score at discharge from outpatient rehabilitation. Multiple regression models investigated the predictive value of each variable for SP outcome, separately for each care pathway. Main findings show that for the inpatient-outpatient sample, three variables (education years, MPAI-4 Ability and Adjustment scores at rehabilitation intake) significantly predicted SP outcome, with the regression model accounting for 49% of the variance. For the outpatient sample, five variables (pre-morbid hypertension and mental health diagnosis, total indirect rehabilitation hours received, MPAI-4 Abilities and Adjustment scores at rehabilitation intake) significantly predicted SP outcome, with the regression model accounting for 47% of the variance. In conclusion, different pre-morbid and post-injury variables are involved in predicting SP, depending on the rehabilitation path followed. The predictive value of those variables could help clinicians identify patients more likely of showing poorer SP at discharge and who may require additional or different interventions.

Correlation of MLR with CRP and MPVPCR with LED in Traumatic Brain Injury

BACKGROUND: Traumatic brain injury (TBI) contributes greatly to high rates of death and disability globally. It may be divided into primary and secondary injuries. Primary head injuries occur at the moment of impact which causes mechanical loads and accelerations both linearly and rotationally, causing injury to the brain. After the primary brain injury, further biochemical and cellular processes occur that lead to secondary injury. Secondary insult in TBI may lead to several neuroinflammation processes that are reflected on laboratory markers. The monocyte-lymphocyte ratio and mean platelet volume-platelet count ratio (MPVPCR) theoretically have the potential to be used as neuroinflammation markers in TBI. AIM: This study was conducted to assess the relationship between monocyte-lymphocyte ratio (MLR), MPVPCR with both C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) regarded as inflammation markers in relation to secondary brain injury. METHODS: This study was a cross-sectional prospective analytic observational study conducted at the Sanglah hospital emergency department from February to May 2022. Patients diagnosed with TBI aged 18 years and over that were willing to be included in the study by consecutive sampling. Patients with a history of autoimmune disease, history of taking immunosuppressant drugs, and fractures of > 2 long bones were excluded and the presence of infection characterized by fever was excluded from the study. History taking and physical examination were done to obtain data regarding age, gender, mechanism of injury, Glasgow Coma Scale, fainting duration, and memory loss. The blood sample was taken at 24 h after trauma to obtain MLR, MPVPCR, CRP, and ESR results. Pearson correlation test was done to determine the correlation between MLR and MPVPCR with CRP and LED. RESULTS: There are a total of 85 patients included in this study with the mean of age which is 36 ± 2.5 years old. Most of them are men (71.3%) with the mean of GCS on admission which is 12. Mean ± (SD) of the monocyte, lymphocyte, and platelet was 1.12 ± 0.82 × 103/μL, 1.83 ± 1.69 × 103/μL, and 259.34 ± 85.79 × 103/μL consecutively. MLR with CRP had a weak positive correlation and was statistically significant (r = 0.215; p = 0.045), as well as MPVPCR with ESR also had a weak positive correlation and was statistically significant (r = 0.276; p = 0.010). While both MLR with ESR and MPVPCR with CRP had no correlation. CONCLUSION: MLR can be an option representing CRP in predicting the magnitude of inflammation in head injury and MPVPCR can be considered to be used as a predictor of thrombotic phenomena in TBI.

Inflammasomes as biomarkers and therapeutic targets in traumatic brain injury and related-neurodegenerative diseases: A comprehensive overview

Given the ambiguity surrounding traumatic brain injury (TBI) pathophysiology and the lack of any Food and Drug Administration (FDA)-approved neurotherapeutic drugs, there is an increasing need to better understand the mechanisms of TBI. Recently, the roles of inflammasomes have been highlighted as both potential therapeutic targets and diagnostic markers in different neurodegenerative disorders. Indeed, inflammasome activation plays a pivotal function in the central nervous system (CNS) response to many neurological conditions, as well as to several neurodegenerative disorders, specifically, TBI. This comprehensive review summarizes and critically discusses the mechanisms that govern the activation and assembly of inflammasome complexes and the major methods used to study inflammasome activation in TBI and its implication for other neurodegenerative disorders. Also, we will review how inflammasome activation is critical in CNS homeostasis and pathogenesis, and how it can impact chronic TBI sequalae and increase the risk of developing neurodegenerative diseases. Additionally, we discuss the recent updates on inflammasome-related biomarkers and the potential to utilize inflammasomes as putative therapeutic targets that hold the potential to better diagnose and treat subjects with TBI.

[Treatment of diseases with consequences of traumatic brain injury]

Traumatic brain injury (TBI) is one of the leading causes of neurological morbidity, disability and mortality in all age groups of the population. As a result of the general increase in the number of cases of brain injuries, there is a significant increase in the consequences of TBI, the dominant part of which is asthenic, vegetative, cognitive, emotional and liquorodynamic disorders. Therapeutic measures in the long-term period of TBI should be carried out intensively as in the first 12 months. after TBI, and in the future, considering the ongoing processes of morphofunctional maturation of the CNS and high brain plasticity, especially in childhood. Syndromic treatment should be differentiated and pathogenetically substantiated. The article covers in detail the modern methods of drug therapy in patients with remote residual effects of brain injury. The high efficiency of the use of the neuroprotective drug Cortexin in the correction of the consequences of TBI was shown.

Neuroinflammatory Biomarkers for Traumatic Brain Injury Diagnosis and Prognosis: A TRACK-TBI Pilot Study

The relationship between systemic inflammation and secondary injury in traumatic brain injury (TBI) is complex. We investigated associations between inflammatory markers and clinical confirmation of TBI diagnosis and prognosis. The prospective TRACK-TBI Pilot (Transforming Research and Clinical Knowledge in Traumatic Brain Injury Pilot) study enrolled TBI patients triaged to head computed tomography (CT) and received blood draw within 24 h of injury. Healthy controls (HCs) and orthopedic controls (OCs) were included. Thirty-one inflammatory markers were analyzed from plasma. Area under the receiver operating characteristic curve (AUC) was used to evaluate discriminatory ability. AUC >0.7 was considered acceptable. Criteria included: TBI diagnosis (vs. OC/HC); moderate/severe vs. mild TBI (Glasgow Coma Scale; GCS); radiographic TBI (CT positive vs. CT negative); 3- and 6-month Glasgow Outcome Scale-Extended (GOSE) dichotomized to death/greater relative disability versus less relative disability (GOSE 1-4/5-8); and incomplete versus full recovery (GOSE <8/ = 8). One-hundred sixty TBI subjects, 28 OCs, and 18 HCs were included. Markers discriminating TBI/OC: HMGB-1 (AUC = 0.835), IL-1b (0.795), IL-16 (0.784), IL-7 (0.742), and TARC (0.731). Markers discriminating GCS 3-12/13-15: IL-6 (AUC = 0.747), CRP (0.726), IL-15 (0.720), and SAA (0.716). Markers discriminating CT positive/CT negative: SAA (AUC = 0.767), IL-6 (0.757), CRP (0.733), and IL-15 (0.724). At 3 months, IL-15 (AUC = 0.738) and IL-2 (0.705) discriminated GOSE 5-8/1-4. At 6 months, IL-15 discriminated GOSE 1-4/5-8 (AUC = 0.704) and GOSE <8/ = 8 (0.711); SAA discriminated GOSE 1-4/5-8 (0.704). We identified a profile of acute circulating inflammatory proteins with potential relevance for TBI diagnosis, severity differentiation, and prognosis. IL-15 and serum amyloid A are priority markers with acceptable discrimination across multiple diagnostic and outcome categories. Validation in larger prospective cohorts is needed. ClinicalTrials.gov Registration: NCT01565551.

Comparative safety of multiple doses of erythropoietin for the treatment of traumatic brain injury: A systematic review and network meta-analysis

Introduction

Over the past few decades, advances in traumatic brain injury (TBI) pathology research have dynamically enriched our knowledge. Therefore, we aimed to systematically elucidate the safety and efficacy of erythropoietin (EPO) dosing regimens in patients with TBI.

Methods

Data search included PubMed, the Cochrane Library, Embase, Web of Science, and ClinicalTrials.gov for related research published before July 2022. The network meta-analysis was conducted using ADDIS 1.16.8, and the CINeMA tool was used to assess the quality level of evidence.

Results

A total of six RCTs involving 981 patients were included in the network meta-analysis. EPO did not significantly reduce mortality in patients with TBI, but its risk of death decreased with increasing dosage (odds ratio (OR) of 12,000u vs. placebo = 0.98, 95% CI: 0.03-40.34; OR of group 30,000u vs. placebo = 0.56, 95% CI: 0.06-5.88; OR of 40,000u vs. placebo = 0.35, 95% CI: 0.01-9.43; OR of 70,000u vs. placebo = 0.29, 95% CI: 0.01-9.26; OR of group 80,000u vs. placebo = 0.22, 95% CI: 0.00-7.45). A total of three studies involving 739 patients showed that EPO did not increase the incidence of deep vein thrombosis in patients with TBI. However, the risk tended to rise as the dosage increased. Another two studies demonstrated that EPO did not increase the incidence of pulmonary embolism. The quality of evidence for all outcomes was low to moderate.

Conclusion

Although the efficacy of EPO was not statistically demonstrated, we found a trend toward an association between EPO dosage and reduced mortality and increased embolic events in patients with TBI. More high-quality original studies should be conducted to obtain strong evidence on the optimal dosage of EPO.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=272500. The study protocol was registered with PROSPERO (CRD42021272500).

Prognostic Role of Catecholamine in Moderate-to-Severe Traumatic Brain Injury: A Prospective Observational Cohort Study

Objective  Traumatic brain injury leads to the activation of sympathetic nervous system and elevation in serum catecholamine levels. The aim of this study was to determine whether catecholamine level obtained within 24 hours of traumatic brain injury provides a reliable prognostic marker for outcome.

Materials and Methods  This study was a prospective observational cohort study on 36 moderate-to-severe traumatic brain injury. Plasma epinephrine (E), norepinephrine (NE), and dopamine (DA) levels were measured by using computed tomography enzyme-linked immunosorbent assay test and compared with Glasgow coma scale (GCS) that was obtained concurrently. Neurological outcome was determined by GCS at day 7 of treatment and by Glasgow outcome scale at mean follow-up of 9.73 ± 2.26 months.

Results  Patients with GCS 3 to 4 had markedly increase in baseline mean E (771.5 ± 126.0), NE (2,225.0 ± 215.4), and DA (590.2 ± 38.8) levels as compared with control, while patients with better GCS (11–12) had mildly elevated levels. Patients with GCS 5 to 10 had intermediate values. Cases with markedly elevated baseline E, NE, and DA level were either died or remained in poor GCS (3 or 4) at day 7 of treatment and remained in persistent vegetative state at mean follow-up of 9.73 ± 2.26 months. Cases with only mildly elevated E, NE, and DA level were improved to better GCS on treatment and had good recovery on follow-up.

Conclusion  These data indicate that a markedly elevated catecholamine level was an excellent endogenous and readily quantifiable marker that appears to reflect the extent of brain injury and predict the likelihood of recovery.

Hypoxia-pretreated mesenchymal stem cell-derived exosomes-loaded low-temperature extrusion 3D-printed implants for neural regeneration after traumatic brain injury in canines

Regenerating brain defects after traumatic brain injury (TBI) still remains a significant difficulty, which has motivated interest in 3D printing to design superior replacements for brain implantation. Collagen has been applied to deliver cells or certain neurotrophic factors for neuroregeneration. However, its fast degradation rate and poor mechanical strength prevent it from being an excellent implant material after TBI. In the present study, we prepared 3D-printed collagen/silk fibroin/hypoxia-pretreated human umbilical cord mesenchymal stem cells (HUCMSCs)-derived exosomes scaffolds (3D-CS-HMExos), which possessed favorable physical properties suitable biocompatibility and biodegradability and were attractive candidates for TBI treatment. Furthermore, inspired by exosomal alterations resulting from cells in different external microenvironments, exosomes were engineered through hypoxia stimulation of mesenchymal stem cells and were proposed as an alternative therapy for promoting neuroregeneration after TBI. We designed hypoxia-preconditioned (Hypo) exosomes derived from HUCMSCs (Hypo-MExos) and proposed them as a selective therapy to promote neuroregeneration after TBI. For the current study, 3D-CS-HMExos were prepared for implantation into the injured brains of beagle dogs. The addition of hypoxia-induced exosomes further exhibited better biocompatibility and neuroregeneration ability. Our results revealed that 3D-CS-HMExos could significantly promote neuroregeneration and angiogenesis due to the doping of hypoxia-induced exosomes. In addition, the 3D-CS-HMExos further inhibited nerve cell apoptosis and proinflammatory factor (TNF-α and IL-6) expression and promoted the expression of an anti-inflammatory factor (IL-10), ultimately enhancing the motor functional recovery of TBI. We proposed that the 3D-CS-loaded encapsulated hypoxia-induced exosomes allowed an adaptable environment for neuroregeneration, inhibition of inflammatory factors and promotion of motor function recovery in TBI beagle dogs. These beneficial effects implied that 3D-CS-HMExos implants could serve as a favorable strategy for defect cavity repair after TBI.

Effect of computerized cognitive rehabilitation in comparison between young and old age after traumatic brain injury

INTRODUCTION

Cognitive dysfunction reduces patients' quality of life and social participation with traumatic brain injury (TBI). Computerized cognitive rehabilitation is increasingly being used for cognitive therapy in TBI patients. The purpose of this study was to investigate the influence of age on the effect of computerized cognitive rehabilitation in cognitive dysfunction after TBI.

MATERIAL AND METHODS

A total of 34 patients with cognitive dysfunction after TBI were enrolled. Participants performed 30 sessions of computerized cognitive rehabilitation (Comcog) for 6 weeks. A cognitive evaluation was performed before and after treatment with Mini-Mental State Examination (MMSE) and Computerized Neurophyschologic Test (CNT).

RESULTS

There were no cognitive tests that differed between the young group and the old group at baseline. However, after computerized cognitive rehabilitation, the young group showed significant improvement compared to the old group in verbal memory, visual memory, attention, and visuo-motor coordination tests. The young group showed improvement in MMSE, verbal and visual memory, and visuo-motor coordination tests after computerized cognitive rehabilitation. In contrast, the old group showed significant improvement only in MMSE and visual learning test, one of the visual memory tests.

CONCLUSION

Our findings demonstrate that age may be an important factor related to the effect of computer cognitive rehabilitation on cognitive dysfunction after TBI. Methodologically more ordered studies with larger sample sizes are needed in the future.

Automated Pupillometry as an Assessment Tool for Intracranial Hemodynamics in Septic Patients

Impaired cerebral autoregulation (CA) may increase the risk of brain hypoperfusion in septic patients. Sepsis dysregulates the autonomic nervous system (ANS), potentially affecting CA. ANS function can be assessed through the pupillary light reflex (PLR). The aim of this prospective, observational study was to investigate the association between CA and PLR in adult septic patients. Transcranial Doppler was used to assess CA and calculate estimated cerebral perfusion pressure (eCPP) and intracranial pressure (eICP). An automated pupillometer (AP) was used to record Neurological Pupil Index (NPi), constriction (CV) and dilation (DV) velocities. The primary outcome was the relationship between AP-derived variables with CA; the secondary outcome was the association between AP-derived variables with eCPP and/or eICP. Among 40 included patients, 21 (53%) had impaired CA, 22 (55%) had low eCPP (<60 mmHg) and 15 (38%) had high eICP (>16 mmHg). DV was lower in patients with impaired CA compared to others; DV predicted impaired CA with area under the curve, AUROC= 0.78 [95% Confidence Interval, CI 0.63−0.94]; DV < 2.2 mm/s had sensitivity 85% and specificity 69% for impaired CA. Patients with low eCPP or high eICP had lower NPi values than others. NPi was correlated with eCPP (r = 0.77, p < 0.01) and eICP (r = −0.87, p < 0.01). Automated pupillometry may play a role to assess brain hemodynamics in septic patients.

Prediction of Intraparenchymal Hemorrhage Progression and Neurologic Outcome in Traumatic Brain Injury Patients Using Radiomics Score and Clinical Parameters

(1) Background: Radiomics analysis of spontaneous intracerebral hemorrhages on computed tomography (CT) images has been proven effective in predicting hematoma expansion and poor neurologic outcome. In contrast, there is limited evidence on its predictive abilities for traumatic intraparenchymal hemorrhage (IPH). (2) Methods: A retrospective analysis of 107 traumatic IPH patients was conducted. Among them, 45 patients (42.1%) showed hemorrhagic progression of contusion (HPC) and 51 patients (47.7%) had poor neurological outcome. The IPH on the initial CT was manually segmented for radiomics analysis. After feature extraction, selection and repeatability evaluation, several machine learning algorithms were used to derive radiomics scores (R-scores) for the prediction of HPC and poor neurologic outcome. (3) Results: The AUCs for R-scores alone to predict HPC and poor neurologic outcome were 0.76 and 0.81, respectively. Clinical parameters were used to build comparison models. For HPC prediction, variables including age, multiple IPH, subdural hemorrhage, Injury Severity Score (ISS), international normalized ratio (INR) and IPH volume taken together yielded an AUC of 0.74, which was significantly (p = 0.022) increased to 0.83 after incorporation of the R-score in a combined model. For poor neurologic outcome prediction, clinical variables of age, Glasgow Coma Scale, ISS, INR and IPH volume showed high predictability with an AUC of 0.92, and further incorporation of the R-score did not improve the AUC. (4) Conclusion: The results suggest that radiomics analysis of IPH lesions on initial CT images has the potential to predict HPC and poor neurologic outcome in traumatic IPH patients. The clinical and R-score combined model further improves the performance of HPC prediction.

Head Phantom Optical Properties Validation for Near-Infrared Measurements: A Comparison with Animal Tissue

The interest in optical healthcare technologies has increased significantly over the recent years. The innovation of new optical technologies such as Near Infrared Spectroscopy (NIRS), used for the monitoring of brain perfusion, demands a comprehensive understanding and knowledge of the light tissue interaction. Phantoms can provide a rigorous, reproducible and convenient approach for evaluating an optical sensor's performance. However, up to date literature does not provide a detailed description of a complete head model that involves the human anatomy, physiological changes, and the tissue optical properties. The latter is key for the design, development and testing of optical sensors, such as NIRS technologies. This paper compared the optical properties of the materials chosen to build a head phantom, against the optical properties of real brain and skull tissues extracted from animal models. The spectra of a silicone brain and resin skull samples were compared with the spectra of the respective tissues extracted from pigs and mice. The results of this study demonstrated that both phantom materials have similar optical properties to mice and pigs' tissues. The morphology of the phantom's spectra were very similar to the respective animal tissue comparator.

Prognostic properties of the association between the S‑100B protein levels and the mean cerebral blood flow velocity in patients diagnosed with severe traumatic brain injury

Craniocerebral injury (CBI) is tissue damage caused by a sudden mechanical force. CBI can result in neurological, neuropsychological and psychiatric dysfunctions. Currently, the severity of CBI is assessed using the Glasgow Coma Scale, brain perfusion pressure measurements, transcranial Doppler tests and biochemical markers. This study aimed to determine the applicability of the S-100B protein levels and the time-averaged mean maximum cerebral blood flow velocity (V_mean) as a means of predicting the treatment outcomes of CBI in the first 4 days of hospitalization. The results validated the standard reference ranges previously proposed for the concentration of S-100B (0.05-0.23 µg/l) and the mean of cerebral blood flow velocity (30.9 to 74.1 cm/sec). The following stratification scheme was used to predict the success of treatment: Patients with a Glasgow Outcome Scale (GOS) score ≥4 or GOS <4 were stratified into ‘favorable’ and ‘unfavorable’ groups, respectively. The favorable group showed relatively constant levels of the S-100B protein close to the normal range and exhibited an increase in V_mean, but this was still within the normal range. The unfavorable group exhibited a high level of S-100B protein and increased V_mean outside of the normal ranges. The changes in the levels of S-100B in the unfavorable and favorable groups were -0.03 and -0.006 mg/l/h, respectively. Furthermore, the rate of decrease in the V_mean value in the unfavorable and favorable groups were -0.26 and -0.18 cm/sec/h, respectively. This study showed that constant levels of S-100B protein, even slightly above the normal range, associated with an increase in V_mean was indicative of a positive therapeutic outcome. However, additional research is required to obtain the appropriate statistical strength required for clinical practice.

Immunomodulatory protein from ganoderma microsporum protects against oxidative damages and cognitive impairments after traumatic brain injury

A traumatic brain injury (TBI) causes abnormal proliferation of neuroglial cells, and over-release of glutamate induces oxidative stress and inflammation and leads to neuronal death, memory deficits, and even death if the condition is severe. There is currently no effective treatment for TBI. Recent interests have focused on the benefits of supplements or natural products like Ganoderma. Studies have indicated that immunomodulatory protein from Ganoderma microsporum (GMI) inhibits oxidative stress in lung cancer cells A549 and induces cancer cell death by causing intracellular autophagy. However, no evidence has shown the application of GMI on TBI. Thus, this study addressed whether GMI could be used to prevent or treat TBI through its anti-inflammation and antioxidative effects. We used glutamate-induced excitotoxicity as in vitro model and penetrating brain injury as in vivo model of TBI. We found that GMI inhibits the generation of intracellular reactive oxygen species and reduces neuronal death in cortical neurons against glutamate excitotoxicity. In neurite injury assay, GMI promotes neurite regeneration, the length of the regenerated neurite was even longer than that of the control group. The animal data show that GMI alleviates TBI-induced spatial memory deficits, expedites the restoration of the injured areas, induces the secretion of brain-derived neurotrophic factors, increases the superoxide dismutase 1 (SOD-1) and lowers the astroglial proliferation. It is the first paper to apply GMI to brain-injured diseases and confirms that GMI reduces oxidative stress caused by TBI and improves neurocognitive function. Moreover, the effects show that prevention is better than treatment. Thus, this study provides a potential treatment in naturopathy against TBI.

Use of Hyperoncotic Human Albumin Solution in Severe Traumatic Brain Injury Revisited-A Narrative Review and Meta-Analysis

A significant proportion of patients with a severe traumatic brain injury (TBI) have hypoalbuminemia and require fluid resuscitation. Intravenous fluids can have both favorable and unfavorable consequences because of the risk of hyperhydration and hypo- or hyperosmolar conditions, which may affect the outcome of a TBI. Fluid resuscitation with human albumin solution (HAS) corrects low serum albumin levels and aids in preserving euvolemia in non-brain-injured intensive care units and in perioperative patients. However, the use of HAS for TBI remains controversial. In patients with TBI, the infusion of hypooncotic (4%) HAS was associated with adverse outcomes. The side effects of 4% HAS and the safety and efficacy of hyperoncotic (20-25%) HAS used in the Lund concept of TBI treatment need further investigation. A nonsystematic review, including a meta-analysis of controlled clinical trials, was performed to evaluate hyperoncotic HAS in TBI treatment. For the meta-analysis, the MEDLINE and EMBASE Library databases, as well as journal contents and reference lists, were searched for pertinent articles up to March 2021. Four controlled clinical studies involving 320 patients were included. The first was a randomized trial. Among 165 patients treated with hyperoncotic HAS, according to the Lund concept, 24 (14.5%) died vs. 59 out of 155 control patients (38.1%). A Lund concept intervention using hyperoncotic HAS was associated with a significantly reduced mortality (p = 0.002). Evidence of the beneficial effects of fluid management with hyperoncotic HAS on mortality in patients with TBI is at a high risk of bias. Prospective randomized controlled trials are required, which could lead to changes in clinical practice recommendations for fluid management in patients with TBI.

Tracking Antioxidant Status in Spinal Cord Injured Rodents: A Voltammetric Method Suited for Clinical Translation

BACKGROUND

Spinal cord injury (SCI) triggers a signalling cascade that produces oxidative stress and damages the spinal cord. Voltammetry is a clinically accessible technique to detect, monitor, and guide correction of this potentially reversible secondary injury mechanism. Voltammetry is well suited for clinical translation because the method is inexpensive, simple, rapid, and portable. Voltammetry relies on the measurement of anodic current from a reagent-free, electrochemical reaction on the surface of a small electrode.

METHODS

The present study tested the use of new disposable carbon nanotube based screen printed electrodes (CNT-SPE) for the voltammetric measurement of antioxidant current (AC). Spinal cord, cerebrospinal fluid, and plasma were obtained from Sprague-Dawley rats after SCI. Locomotor function after SCI was assessed by using the Basso, Beattie, Bresnahan (BBB) score.

RESULTS

The more severe SCI caused a decline in spinal cord AC₄₁₉ at 10 minutes (P < 0.05), 4 hours (P < 0.0001), and 1 day (P < 0.01) after injury compared with sham controls. It also caused a decline in plasma AC₃₇₅ at 1 (P < 0.001) and 3 days (P < 0.05) after injury compared with their pre-injury baseline. Spinal cord AC₄₁₉ correlated with plasma AC₃₇₅ (r = 0.49, P < 0.01) and BBB score (r = 0.66, P < 0.0001) at 1 day after SCI.

CONCLUSIONS

AC measured by CNT-SPE demonstrated a time- and severity-dependent decline after SCI. Plasma AC could serve as a surrogate marker for spinal cord AC.

Optic Nerve Sheath Diameter Ultrasound: A Non-Invasive Approach to Evaluate Increased Intracranial Pressure in Critically Ill Pediatric Patients

Early diagnosis of increased intracranial pressure (ICP) is crucial for prompt diagnosis and treatment of intracranial hypertension in critically ill pediatric patients, preventing secondary brain damage and mortality. Although the placement of an external ventricular drain coupled to an external fluid-filled transducer remains the gold standard for continuous ICP monitoring, other non-invasive approaches are constantly being improved and can provide reliable estimates. The use of point-of-care ultrasound (POCUS) for the assessment of ICP has recently become widespread in pediatric emergency and critical care settings, representing a valuable extension of the physical examination. The aim of this manuscript is to review and discuss the basic principles of ultra-sound measurement of the optic nerve sheath diameter (ONSD) and summarize current evidence on its diagnostic value in pediatric patients with ICP. There is increasing evidence that POCUS measurement of the ONSD correlates with ICP, thus appearing as a useful extension of the physical examination in pediatrics, especially in emergency medicine and critical care settings for the initial non-invasive assessment of patients with suspected raised ICP. Its role could be of value even to assess the response to therapy and in the follow-up of patients with diagnosed intracranial hypertension if invasive ICP monitoring is not available. Further studies on more homogeneous and extensive study populations should be performed to establish ONSD reference ranges in the different pediatric ages and to define cut-off values in predicting elevated ICP compared to invasive ICP measurement.

Continuous Renal Replacement Therapy in Acute Brain Injury

Acute brain injury is the sudden and reversible loss of brain self regulation capacity as a disruption of the blood-brain barrier that conditions metabolic and inflammatory disorders that can exacerbate acute kidney injury in a critical setting; specifically it has been described that the alterations of the internal environment that come from the severity of the acute kidney injury increases the risk of endocranial hypertension and cerebral edema; in this context, injuries should be identified and treated in a timely manner with a comprehensive approach. Continuous renal replacement therapy is an extracorporeal purification technique that has been gaining ground in the management of acute kidney injury in critically ill patients. Within its modalities, continuous venous venous hemofiltration is described as the therapy of choice in patients with acute brain injury due to its advantages in maintaining hemodynamic stability and reducing the risk of cerebral edema. Optimal control of variables such as timing to start renal replacement therapy, the prescribed dose, the composition of the replacement fluid and the anticoagulation of the extracorporeal circuit will have a significant impact on the evolution of the neurocritical patient with acute kidney injury. There are limited studies evaluating the role of hemofiltration in this context.

Effect of increased positive end-expiratory pressure on intracranial pressure and cerebral oxygenation: impact of respiratory mechanics and hypovolemia

BACKGROUND

To evaluate the impact of positive end-expiratory pressure (PEEP) on intracranial pressure (ICP) in animals with different respiratory mechanics, baseline ICP and volume status.

METHODS

A total of 50 male adult Bama miniature pigs were involved in four different protocols (n = 20, 12, 12, and 6, respectively). Under the monitoring of ICP, brain tissue oxygen tension and hemodynamical parameters, PEEP was applied in increments of 5 cm H₂O from 5 to 25 cm H₂O. Measurements were taken in pigs with normal ICP and normovolemia (Series I), or with intracranial hypertension (via inflating intracranial balloon catheter) and normovolemia (Series II), or with intracranial hypertension and hypovolemia (via exsanguination) (Series III). Pigs randomized to the control group received only hydrochloride instillation while the intervention group received additional chest wall strapping. Common carotid arterial blood flow before and after exsanguination at each PEEP level was measured in pigs with intracranial hypertension and chest wall strapping (Series IV).

RESULTS

ICP was elevated by increased PEEP in both normal ICP and intracranial hypertension conditions in animals with normal blood volume, while resulted in decreased ICP with PEEP increments in animals with hypovolemia. Increasing PEEP resulted in a decrease in brain tissue oxygen tension in both normovolemic and hypovolemic conditions. The impacts of PEEP on hemodynamical parameters, ICP and brain tissue oxygen tension became more evident with increased chest wall elastance. Compare to normovolemic condition, common carotid arterial blood flow was further lowered when PEEP was raised in the condition of hypovolemia.

CONCLUSIONS

The impacts of PEEP on ICP and cerebral oxygenation are determined by both volume status and respiratory mechanics. Potential conditions that may increase chest wall elastance should also be ruled out to avoid the deleterious effects of PEEP.

Usability of the Level of the S100B Protein, the Gosling Pulsatility Index, and the Jugular Venous Oxygen Saturation for the Prediction of Mortality and Morbidity in Patients with Severe Traumatic Brain Injury

The high frequency of traumatic brain injury imposes severe economic stress on health and insurance services. The objective of this study was to analyze the association between the serum S100B protein, the Gosling pulsatility index (PI), and the level of oxygen saturation at the tip of the internal jugular vein (SjVO2%) in patients diagnosed with severe TBI. The severity of TBI was assessed by a GCS score ≤ 8 stratified by Glasgow outcome scale (GOS) measured on the day of discharge from the hospital. Two groups were included: GOS < 4 (unfavorable group (UG)) and GOS ≥ 4 (favorable group (UG)). S100B levels were higher in the UG than in the FG. PI levels in the UG were also substantially higher than in the FG. There were similar levels of SjVO2 in the two groups. This study confirmed that serum S100B levels were higher in patients with unfavorable outcomes than in those with favorable outcomes. Moreover, a clear demarcation in PI between unfavorable and FGs was observed. This report shows that mortality and morbidity rates in patients with traumatic brain injury can be assessed within the first 4 days of hospitalization using the S100B protein, PI values, and SjVO2.

Neural stem cell delivery using brain-derived tissue-specific bioink for recovering from traumatic brain injury

Traumatic brain injury is one of the leading causes of accidental death and disability. The loss of parts in a severely injured brain induces edema, neuronal apoptosis, and neuroinflammation. Recently, stem cell transplantation demonstrated regenerative efficacy in an injured brain. However, the efficacy of current stem cell therapy needs improvement to resolve issues such as low survival of implanted stem cells and low efficacy of differentiation into respective cells. We developed brain-derived decellularized extracellular matrix (BdECM) bioink that is printable and has native brain-like stiffness. This study aimed to fabricate injured cavity-fit scaffold with BdECM bioink and assessed the utility of BdECM bioink for stem cell delivery to a traumatically injured brain. Our BdECM bioink had shear thinning property for three-dimensional (3D)-cell-printing and physical properties and fiber structures comparable to those of the native brain, which is important for tissue integration after implantation. The human neural stem cells (NSCs) (F3 cells) laden with BdECM bioink were found to be fully differentiated to neurons; the levels of markers for mature differentiated neurons were higher than those observed with collagen bioinkin vitro. Moreover, the BdECM bioink demonstrated potential in defect-fit carrier fabrication with 3D cell-printing, based on the rheological properties and shape fidelity of the material. As F3 cell-laden BdECM bioink was transplanted into the motor cortex of a rat brain, high efficacy of differentiation into mature neurons was observed in the transplanted NSCs; notably increased level of MAP2, a marker of neuronal differentiation, was observed. Furthermore, the transplanted-cell bioink suppressed reactive astrogliosis and microglial activation that may impede regeneration of the injured brain. The brain-specific material reported here is favorable for NSC differentiation and suppression of neuroinflammation and is expected to successfully support regeneration of a traumatically injured brain.

Serum biomarkers in severe paediatric traumatic brain injury-a narrative review

Severe traumatic brain injury continues to present complex management and prediction challenges for the clinician. While there is some evidence that better systems of care can improve outcome, multiple multi-centre randomised controlled trials of specific therapies have consistently failed to show benefit. In addition, clinicians are challenged in attempting to accurately predict which children will recover well and which children will have severe and persisting neurocognitive deficits. Traumatic brain injury is vastly heterogeneous and so it is not surprising that one therapy or approach, when applied to a mixed cohort of children in a clinical trial setting, has yielded disappointing results. Children with severe traumatic brain injury have vastly different brain injury pathologies of widely varying severity, in any number of anatomical locations at what may be disparate stages of brain development. This heterogeneity may also explain why clinicians are unable to accurately predict outcome. Biomarkers are objective molecular signatures of injury that are released following traumatic brain injury and may represent a way of unifying the heterogeneity of traumatic brain injury into a single biosignature. Biomarkers hold promise to diagnose brain injury severity, guide intervention selection for clinical trials, or provide vital prognostic information so that early intervention and rehabilitation can be planned much earlier in the course of a child's recovery. Serum S100B and serum NSE levels show promise as a diagnostic tool with biomarker levels significantly higher in children with severe TBI including children with inflicted and non-inflicted head injury. Serum S100B and serum NSE also show promise as a predictor of neurodevelopmental outcome. The role of biomarkers in traumatic brain injury is an evolving field with the potential for clinical application within the next few years.

Association between vasopressor use and mortality in patients with severe traumatic brain injury: a nationwide retrospective cohort study in Japan

Aim

Vasopressors are frequently incorporated into severe traumatic brain injury management algorithms. However, evidence regarding their clinical effectiveness is lacking. We undertook a nationwide retrospective cohort study to determine the association between vasopressor use and mortality in patients with severe traumatic brain injury.

Methods

Data were collected between January 2004 and December 2018 from the Japanese Trauma Data Bank, which includes data from 272 emergency hospitals in Japan. Adults aged 16 years and over with severe traumatic brain injury but without major extracranial injuries were examined. A severe traumatic brain injury was defined based on a Glasgow Coma Scale score of 3–8 on admission. Multivariable analysis and propensity score matching were carried out. Statistical significance was assessed using 95% confidence intervals.

Results

In total, 10,295 patients were eligible for analysis, with 654 included in the vasopressor group and 9,641 included in the nonvasopressor group. The proportion of deaths at hospital discharge was higher in the vasopressor group than in the nonvasopressor group (81.80% [535/654] versus 40.24% [3,880/9,641]). This finding was confirmed in a multivariable logistic regression analysis (adjusted odds ratio, 5.37; 95% confidence interval, 4.23–6.81). Among propensity score‐matched patients adjusted for severity, the proportion of deaths at hospital discharge remained higher in the vasopressor group than in the nonvasopressor group (81.87% [533/651] versus 56.22% [366/651]) (odds ratio, 3.52; 95% confidence interval, 2.73–4.53).

Conclusion

The study results suggest that vasopressor use in patients with severe isolated traumatic brain injury is associated with a higher mortality at hospital discharge.