Multiorgan Dysfunction After Severe Traumatic Brain Injury: Epidemiology, Mechanisms, and Clinical Management

Traumatic Brain Injury and Traumatic Spinal Cord Injury

OBJECTIVE

This article reviews the mechanisms of primary traumatic injury to the brain and spinal cord, with an emphasis on grading severity, identifying surgical indications, anticipating complications, and managing secondary injury.

LATEST DEVELOPMENTS

Serum biomarkers have emerged for clinical decision making and prognosis after traumatic injury. Cortical spreading depolarization has been identified as a potentially modifiable mechanism of secondary injury after traumatic brain injury. Innovative methods to detect covert consciousness may inform prognosis and enrich future studies of coma recovery. The time-sensitive nature of spinal decompression is being elucidated.

ESSENTIAL POINTS

Proven management strategies for patients with severe neurotrauma in the intensive care unit include surgical decompression when appropriate, the optimization of perfusion, and the anticipation and treatment of complications. Despite validated models, predicting outcomes after traumatic brain injury remains challenging, requiring prognostic humility and a model of shared decision making with surrogate decision makers to establish care goals. Penetrating injuries, especially gunshot wounds, are often devastating and require public health and policy approaches that target prevention.

Critical Knowledge Gaps and Future Priorities Regarding the Intestinal Barrier Damage After Traumatic Brain Injury

The analysis aims to provide a comprehensive understanding of the current landscape of research on the Intestinal barrier damage after traumatic brain injury (TBI), elucidate specific mechanisms, and address knowledge gaps to help guide the development of targeted therapeutic interventions and improve outcomes for individuals with TBI. A total of 2756 relevant publications by 13,778 authors affiliated within 3198 institutions in 79 countries were retrieved from the Web of Science. These publications have been indexed by 1139 journals and cited 158, 525 references. The most productive author in this field was Sikiric P, and the University of Pittsburgh was identified as the most influential institution. The United States was found to be the leading country in terms of article output and held a dominant position in this field. The International Journal of Molecular Sciences was identified as a major source of publications in this area. In terms of collaboration, the cooperation between the United States and China was found to be the most extensive among countries, institutions, and authors, indicating a high level of influence in this field. Keyword co-occurrence network analysis revealed several hotspots in this field, including the microbiome-gut-brain axis, endoplasmic reticulum stress, cellular autophagy, ischemia-reperfusion, tight junctions, and intestinal permeability. The analysis of keyword citation bursts suggested that ecological imbalance and gut microbiota may be the forefront of future research. The findings of this study can serve as a reference and guiding perspective for future research in this field.

Dysregulated brain-gut axis in the setting of traumatic brain injury: review of mechanisms and anti-inflammatory pharmacotherapies

Traumatic brain injury (TBI) is a chronic and debilitating disease, associated with a high risk of psychiatric and neurodegenerative diseases. Despite significant advancements in improving outcomes, the lack of effective treatments underscore the urgent need for innovative therapeutic strategies. The brain-gut axis has emerged as a crucial bidirectional pathway connecting the brain and the gastrointestinal (GI) system through an intricate network of neuronal, hormonal, and immunological pathways. Four main pathways are primarily implicated in this crosstalk, including the systemic immune system, autonomic and enteric nervous systems, neuroendocrine system, and microbiome. TBI induces profound changes in the gut, initiating an unrestrained vicious cycle that exacerbates brain injury through the brain-gut axis. Alterations in the gut include mucosal damage associated with the malabsorption of nutrients/electrolytes, disintegration of the intestinal barrier, increased infiltration of systemic immune cells, dysmotility, dysbiosis, enteroendocrine cell (EEC) dysfunction and disruption in the enteric nervous system (ENS) and autonomic nervous system (ANS). Collectively, these changes further contribute to brain neuroinflammation and neurodegeneration via the gut-brain axis. In this review article, we elucidate the roles of various anti-inflammatory pharmacotherapies capable of attenuating the dysregulated inflammatory response along the brain-gut axis in TBI. These agents include hormones such as serotonin, ghrelin, and progesterone, ANS regulators such as beta-blockers, lipid-lowering drugs like statins, and intestinal flora modulators such as probiotics and antibiotics. They attenuate neuroinflammation by targeting distinct inflammatory pathways in both the brain and the gut post-TBI. These therapeutic agents exhibit promising potential in mitigating inflammation along the brain-gut axis and enhancing neurocognitive outcomes for TBI patients.

Association of Early Dexmedetomidine Utilization With Clinical and Functional Outcomes Following Moderate-Severe Traumatic Brain Injury: A Transforming Clinical Research and Knowledge in Traumatic Brain Injury Study

OBJECTIVE

To examine early sedation patterns, as well as the association of dexmedetomidine exposure, with clinical and functional outcomes among mechanically ventilated patients with moderate-severe traumatic brain injury (msTBI).

DESIGN

Retrospective cohort study with prospectively collected data.

SETTING

Eighteen Level-1 Trauma Centers, United States.

PATIENTS

Adult (age > 17) patients with msTBI (as defined by Glasgow Coma Scale < 13) who required mechanical ventilation from the Transforming Clinical Research and Knowledge in TBI (TRACK-TBI) study.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Using propensity-weighted models, we examined the association of early dexmedetomidine exposure (within the first 5 d of ICU admission) with the primary outcome of 6-month Glasgow Outcomes Scale Extended (GOS-E) and the following secondary outcomes: length of hospital stay, hospital mortality, 6-month Disability Rating Scale (DRS), and 6-month mortality. The study population included 352 subjects who required mechanical ventilation within 24 hours of admission. The initial sedative medication was propofol for 240 patients (68%), midazolam for 59 patients (17%), ketamine for 6 patients (2%), dexmedetomidine for 3 patients (1%), and 43 patients (12%) never received continuous sedation. Early dexmedetomidine was administered in 77 of the patients (22%), usually as a second-line agent. Compared with unexposed patients, early dexmedetomidine exposure was not associated with better 6-month GOS-E (weighted odds ratio [OR] = 1.48; 95% CI, 0.98-2.25). Early dexmedetomidine exposure was associated with lower DRS (weighted OR = -3.04; 95% CI, -5.88 to -0.21). In patients requiring ICP monitoring within the first 24 hours of admission, early dexmedetomidine exposure was associated with higher 6-month GOS-E score (OR 2.17; 95% CI, 1.24-3.80), lower DRS score (adjusted mean difference, -5.81; 95% CI, -9.38 to 2.25), and reduced length of hospital stay (hazard ratio = 1.50; 95% CI, 1.02-2.20).

CONCLUSION

Variation exists in early sedation choice among mechanically ventilated patients with msTBI. Early dexmedetomidine exposure was not associated with improved 6-month functional outcomes in the entire population, although may have clinical benefit in patients with indications for ICP monitoring.

Safety, Efficacy, and Clinical Outcomes of Dexmedetomidine for Sedation in Traumatic Brain Injury: A Scoping Review

Dexmedetomidine is a promising alternative sedative agent for moderate-severe Traumatic brain injury (TBI) patients. Although the data are limited, the posited benefits of dexmedetomidine in this population are a reduction in secondary brain injury compared with current standard sedative regimens. In this scoping review, we critically appraised the literature to examine the effects of dexmedetomidine in patients with moderate-severe TBI to examine the safety, efficacy, and cerebral and systemic physiological outcomes within this population. We sought to identify gaps in the literature and generate directions for future research. Two researchers and a librarian queried PubMed, Embase, Scopus, and APA PsycINFO databases. Of 920 studies imported for screening, 11 were identified for inclusion in the review. The primary outcomes in the included studied were cerebral physiology, systemic hemodynamics, sedation levels and delirium, and the presence of paroxysmal sympathetic hyperactivity. Dexmedetomidine dosing ranged from 0.2 to 1 ug/kg/h, with 3 studies using initial boluses of 0.8 to 1.0 ug/kg over 10 minutes. Dexmedetomidine used independently or as an adjunct seems to exhibit a similar hemodynamic safety profile compared with standard sedation regimens, albeit with transient episodes of bradycardia and hypotension, decrease episodes of agitation and may serve to alleviate symptoms of sympathetic hyperactivity. This scoping review suggests that dexmedetomidine is a safe and efficacious sedation strategy in patients with TBI. Given its rapid onset of action and anxiolytic properties, dexmedetomidine may serve as a feasible sedative for TBI patients.

Pulmonary Effects of Traumatic Brain Injury in Mice: A Gene Set Enrichment Analysis

Acute lung injury occurs in 20-25% of cases following traumatic brain injury (TBI). We investigated changes in lung transcriptome expression post-TBI using animal models and bioinformatics. Employing unilateral controlled cortical impact for TBI, we conducted microarray analysis after lung acquisition, followed by gene set enrichment analysis of differentially expressed genes. Our findings indicate significant upregulation of inflammation-related genes and downregulation of nervous system genes. There was enhanced infiltration of adaptive immune cells, evidenced by positive enrichment in Lung-Th1, CD4, and CD8 T cells. Analysis using the Tabula Sapiens database revealed enrichment in lung-adventitial cells, pericytes, myofibroblasts, and fibroblasts, indicating potential effects on lung vasculature and fibrosis. Gene set enrichment analysis linked TBI to lung diseases, notably idiopathic pulmonary hypertension. A Venn diagram overlap analysis identified a common set of 20 genes, with FOSL2 showing the most significant fold change. Additionally, we observed a significant increase in ADRA1A→IL6 production post-TBI using the L1000 library. Our study highlights the impact of brain trauma on lung injury, revealing crucial gene expression changes related to immune cell infiltration, cytokine production, and potential alterations in lung vasculature and fibrosis, along with a specific spectrum of disease influence.

THE NEUROENDOTHELIAL AXIS IN TRAUMATIC BRAIN INJURY: MECHANISMS OF MULTIORGAN DYSFUNCTION, NOVEL THERAPIES, AND FUTURE DIRECTIONS

ABSTRACT

Severe traumatic brain injury (TBI) often initiates a systemic inflammatory response syndrome, which can potentially culminate into multiorgan dysfunction. A central player in this cascade is endotheliopathy, caused by perturbations in homeostatic mechanisms governed by endothelial cells due to injury-induced coagulopathy, heightened sympathoadrenal response, complement activation, and proinflammatory cytokine release. Unique to TBI is the potential disruption of the blood-brain barrier, which may expose neuronal antigens to the peripheral immune system and permit neuroinflammatory mediators to enter systemic circulation, propagating endotheliopathy systemically. This review aims to provide comprehensive insights into the "neuroendothelial axis" underlying endothelial dysfunction after TBI, identify potential diagnostic and prognostic biomarkers, and explore therapeutic strategies targeting these interactions, with the ultimate goal of improving patient outcomes after severe TBI.

Association of Early Dexmedetomidine Utilization With Clinical Outcomes After Moderate-Severe Traumatic Brain Injury: A Retrospective Cohort Study

BACKGROUND

Traumatic brain injury (TBI) is an expensive and common public health problem. Management of TBI oftentimes includes sedation to facilitate mechanical ventilation (MV) for airway protection. Dexmedetomidine has emerged as a potential candidate for improved patient outcomes when used for early sedation after TBI due to its potential modulation of autonomic dysfunction. We examined early sedation patterns, as well as the association of dexmedetomidine exposure with clinical and functional outcomes among mechanically ventilated patients with moderate-severe TBI (msTBI) in the United States.

METHODS

We conducted a retrospective cohort study using data from the Premier dataset and identified a cohort of critically ill adult patients with msTBI who required MV from January 2016 to June 2020. msTBI was defined by head-neck abbreviated injury scale (AIS) values of 3 (serious), 4 (severe), and 5 (critical). We described early continuous sedative utilization patterns. Using propensity-matched models, we examined the association of early dexmedetomidine exposure (within 2 days of intensive care unit [ICU] admission) with the primary outcome of hospital mortality and the following secondary outcomes: hospital length of stay (LOS), days on MV, vasopressor use after the first 2 days of admission, hemodialysis (HD) after the first 2 days of admission, hospital costs, and discharge disposition. All medications, treatments, and procedures were identified using date-stamped hospital charge codes.

RESULTS

The study population included 19,751 subjects who required MV within 2 days of ICU admission. The patients were majority male and white. From 2016 to 2020, the annual percent utilization of dexmedetomidine increased from 4.05% to 8.60%. After propensity score matching, early dexmedetomidine exposure was associated with reduced odds of hospital mortality (odds ratio [OR], 0.59; 95% confidence interval [CI], 0.47-0.74; P < .0001), increased risk for liberation from MV (hazard ratio [HR], 1.20; 95% CI, 1.09-1.33; P = .0003), and reduced LOS (HR, 1.11; 95% CI, 1.01-1.22; P = .033). Exposure to early dexmedetomidine was not associated with odds of HD (OR, 1.14; 95% CI, 0.73-1.78; P = .56), vasopressor utilization (OR, 1.10; 95% CI, 0.78-1.55; P = .60), or increased hospital costs (relative cost ratio, 1.98; 95% CI, 0.93-1.03; P = .66).

CONCLUSIONS

Dexmedetomidine is being utilized increasingly as a sedative for mechanically ventilated patients with msTBI. Early dexmedetomidine exposure may lead to improved patient outcomes in this population.

Oral administration of lysozyme protects against injury of ileum via modulating gut microbiota dysbiosis after severe traumatic brain injury

Objective

The current study sought to clarify the role of lysozyme-regulated gut microbiota and explored the potential therapeutic effects of lysozyme on ileum injury induced by severe traumatic brain injury (sTBI) and bacterial pneumonia in vivo and in vitro experiments.

Methods

Male 6-8-week-old specific pathogen-free (SPF) C57BL/6 mice were randomly divided into Normal group (N), Sham group (S), sTBI group (T), sTBI + or Lysozyme-treated group (L), Normal + Lysozyme group (NL) and Sham group + Lysozyme group (SL). At the day 7 after establishment of the model, mice were anesthetized and the samples were collected. The microbiota in lungs and fresh contents of the ileocecum were analyzed. Lungs and distal ileum were used to detect the degree of injury. The number of Paneth cells and the expression level of lysozyme were assessed. The bacterial translocation was determined. Intestinal organoids culture and co-coculture system was used to test whether lysozyme remodels the intestinal barrier through the gut microbiota.

Results

After oral administration of lysozyme, the intestinal microbiota is rebalanced, the composition of lung microbiota is restored, and translocation of intestinal bacteria is mitigated. Lysozyme administration reinstates lysozyme expression in Paneth cells, thereby reducing intestinal permeability, pathological score, apoptosis rate, and inflammation levels. The gut microbiota, including Oscillospira, Ruminococcus, Alistipes, Butyricicoccus, and Lactobacillus, play a crucial role in regulating and improving intestinal barrier damage and modulating Paneth cells in lysozyme-treated mice. A co-culture system comprising intestinal organoids and brain-derived proteins (BP), which demonstrated that the BP effectively downregulated the expression of lysozyme in intestinal organoids. However, supplementation of lysozyme to this co-culture system failed to restore its expression in intestinal organoids.

Conclusion

The present study unveiled a virtuous cycle whereby oral administration of lysozyme restores Paneth cell's function, mitigates intestinal injury and bacterial translocation through the remodeling of gut microbiota.

Quantifying the effect of cerebral atrophy on head injury risk in elderly individuals: Insights from computational biomechanics and experimental analysis of bridging veins

The objective of this study was to quantitatively investigate the relationship between cerebral atrophy and the risk of injury in elderly individuals. To achieve this, a sophisticated computational biomechanics approach utilizing finite element analysis was employed to simulate the mechanical behavior of the brain and skull under various conditions. In addition, particular emphasis was placed on understanding the role of cerebral bridging veins (BVs) and their mechanical properties at different ages in the occurrence of head injuries. Head models representing healthy brains and five atrophy models were developed based on imaging data. After validation, the models underwent the identical impact loading conditions to enable the simulation of brain damage. The resulting outcomes of the models with brain atrophy were then compared to the results obtained from the healthy model, allowing for a comparative analysis. Simulations showed increased relative displacement with worsening brain atrophy, particularly in the frontal and occipital regions. Compared to the healthy brain model, relative displacement increased by 2.36 %-9.21 % in the atrophy models, indicating an elevated risk of injury. In severe brain atrophy (FEM 6), the strain reached 83.59 % in local model simulations, leading to damage and rupture of cerebral BVs in both young and elderly individuals. Mechanical tests on cerebral BVs demonstrated a negative correlation between age and ultimate force, stress, and strain, suggesting increased susceptibility to damage with age. An observed sharp decline of approximately 50 % in ultimate stress and 35 % in ultimate strain was noted as age increased. We implemented a 50 % reduction in the intensity of head impact forces; nevertheless, vascular damage continues to manifest in the elderly population. To establish a truly safe zone, it is imperative to further decrease the intensity of the impact. This investigation represents a significant step forward in our understanding of the complex interplay between cerebral atrophy, the mechanical properties of BVs at different age, and the risk of head injury in the elderly. Through continued research in this field, we can strive to improve the quality of care, enhance prevention strategies, and ultimately enhance the well-being and safety of the elderly population.

Associated Risk Factors and Impact in Clinical Outcomes of Multiorgan Failure in Patients with TBI

BACKGROUND

Individual extracerebral organ dysfunction is common after severe traumatic brain injury (TBI) and impacts outcomes. However, multiorgan failure (MOF) has received less attention in patients with isolated TBI. Our objective was to analyze the risk factors associated with the development of MOF and its impact in clinical outcomes in patients with TBI.

METHODS

This was an observational, prospective, multicenter study using data from a nationwide registry that currently includes 52 intensive care units (ICUs) in Spain (RETRAUCI). Isolated significant TBI was defined as Abbreviated Injury Scale (AIS) ≥ 3 in the head area with no AIS ≥ 3 in any other anatomical area. Multiorgan failure was defined using the Sequential-related Organ Failure Assessment as the alteration of two or more organs with a score of ≥ 3. We analyzed the contribution of MOF to crude and adjusted mortality (age and AIS head) by using logistic regression analysis. A multiple logistic regression analysis was performed to analyze the risk factors associated with the development of MOF in patients with isolated TBI.

RESULTS

A total of 9790 patients with trauma were admitted to the participating ICUs. Of them, 2964 (30.2%) had AIS head ≥ 3 and no AIS ≥ 3 in any other anatomical area, and these patients constituted the study cohort. Mean age was 54.7 (19.5) years, 76% of patients were men, and ground-level falls were the main mechanism of injury (49.1%). In-hospital mortality was 22.2%. Up to 185 patients with TBI (6.2%) developed MOF during their ICU stay. Crude and adjusted (age and AIS head) mortality was higher in patients who developed MOF (odds ratio 6.28 [95% confidence interval 4.58-8.60] and odds ratio 5.20 [95% confidence interval 3.53-7.45]), respectively. The logistic regression analysis showed that age, hemodynamic instability, the need of packed red blood cells concentrates in the initial 24 h, the severity of brain injury, and the need for invasive neuromonitoring were significantly associated with MOF development.

CONCLUSIONS

MOF occurred in 6.2% of patients with TBI admitted to the ICU and was associated with increased mortality. MOF was associated with age, hemodynamic instability, the need of packed red blood cells concentrates in the initial 24 h, the severity of brain injury, and the need for invasive neuromonitoring.

Systemic immune response in young and elderly patients after traumatic brain injury

BACKGROUND

Traumatic brain injury (TBI) is a leading cause of death and long-term disability worldwide. In addition to primary brain damage, systemic immune alterations occur, with evidence for dysregulated immune responses in aggravating TBI outcome and complications. However, immune dysfunction following TBI has been only partially understood, especially in the elderly who represent a substantial proportion of TBI patients and worst outcome. Therefore, we aimed to conduct an in-depth immunological characterization of TBI patients, by evaluating both adaptive (T and B lymphocytes) and innate (NK and monocytes) immune cells of peripheral blood mononuclear cells (PBMC) collected acutely (< 48 h) after TBI in young (18-45 yo) and elderly (> 65 yo) patients, compared to age-matched controls, and also the levels of inflammatory biomarkers.

RESULTS

Our data show that young respond differently than elderly to TBI, highlighting the immune unfavourable status of elderly compared to young patients. While in young only CD4 T lymphocytes are activated by TBI, in elderly both CD4 and CD8 T cells are affected, and are induced to differentiate into subtypes with low cytotoxic activity, such as central memory CD4 T cells and memory precursor effector CD8 T cells. Moreover, TBI enhances the frequency of subsets that have not been previously investigated in TBI, namely the double negative CD27- IgD- and CD38-CD24- B lymphocytes, and CD56dim CD16- NK cells, both in young and elderly patients. TBI reduces the production of pro-inflammatory cytokines TNF-α and IL-6, and the expression of HLA-DM, HLA-DR, CD86/B7-2 in monocytes, suggesting a compromised ability to drive a pro-inflammatory response and to efficiently act as antigen presenting cells.

CONCLUSIONS

We described the acute immunological response induced by TBI and its relation with injury severity, which could contribute to pathologic evolution and possibly outcome. The focus on age-related immunological differences could help design specific therapeutic interventions based on patients' characteristics.

Association of Brain Injury Biomarkers and Circulatory Shock Following Moderate-Severe Traumatic Brain Injury: A TRACK-TBI Study

INTRODUCTION

Early circulatory shock following traumatic brain injury (TBI) is a multifactorial process; however, the impact of brain injury biomarkers on the risk of shock has not been evaluated. We examined the association between neuronal injury biomarker levels and the development of circulatory shock following moderate-severe TBI.

METHODS

In this retrospective cohort study, we examined adults with moderate-severe TBI (Glasgow Coma Scale score <13) enrolled in the TRACK-TBI study, an 18-center prospective TBI cohort study. The exposures were day-1 levels of neuronal injury biomarkers (glial fibrillary acidic protein, ubiquitin C-terminal hydrolase-L1 [UCH-L1], S100 calcium-binding protein B [S100B], neuron-specific enolase), and of an inflammatory biomarker (high-sensitivity C-reactive protein). The primary outcome was the development of circulatory shock, defined as cardiovascular Sequential Organ Failure Assessment Score ≥2 within 72 hours of admission. Association between day-1 biomarker levels and the development of circulatory shock was assessed with regression analysis.

RESULTS

The study included 392 subjects, with a mean age of 40 years; 314 (80%) were male and 165 (42%) developed circulatory shock. Median (interquartile range) day-1 levels of UCH-L1 (994.8 [518.7 to 1988.2] pg/mL vs. 548.1 [280.2 to 1151.9] pg/mL; P <0.0001) and S100B (0.47 μg/mL [0.25 to 0.88] vs. 0.27 [0.16 to 0.46] μg/mL; P <0.0001) were elevated in those who developed early circulatory shock compared with those who did not. In multivariable regression, there were associations between levels of both UCH-L1 (odds ratio, 1.63 [95% confidence interval, 1.25-2.12]; P <0.0005) and S100B (odds ratio, 1.73 [95% confidence interval 1.27-2.36]; P <0.0005) with the development of circulatory shock.

CONCLUSION

Neuronal injury biomarkers may provide the improved mechanistic understanding and possibly early identification of patients at risk for early circulatory shock following moderate-severe TBI.

Circulating extracellular vesicles from patients with traumatic brain injury induce cerebrovascular endothelial dysfunction

Endothelial dysfunction is a key proponent of pathophysiological process of traumatic brain injury (TBI). We previously demonstrated that extracellular vesicles (EVs) released from injured brains led to endothelial barrier disruption and vascular leakage. However, the molecular mechanisms of this EV-induced endothelial dysfunction (endotheliopathy) remain unclear. Here, we enriched plasma EVs from TBI patients (TEVs), and detected high mobility group box 1 (HMGB1) exposure to 50.33 ± 10.17% of TEVs and the number of HMGB1⁺TEVs correlated with injury severity. We then investigated for the first time the impact of TEVs on endothelial function using adoptive transfer models. We found that TEVs induced dysfunction of cultured human umbilical vein endothelial cells and mediated endothelial dysfunction in both normal and TBI mice, which were propagated through the HMGB1-activated receptor for advanced glycation end products (RAGE)/Cathepsin B signaling, and the resultant NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome activation and canonical caspase-1/gasdermin D (GSDMD)-dependent pyroptosis. Finally, von Willebrand factor (VWF) was detected on the surface of 77.01 ± 7.51% of HMGB1⁺TEVs. The TEV-mediated endotheliopathy was reversed by a polyclonal VWF antibody, indicating that VWF might serve a coupling factor that tethered TEVs to ECs, thus facilitating HMGB1-induced endotheliopathy. These results suggest that circulating EVs isolated from patients with TBI alone are sufficient to induce endothelial dysfunction and contribute to secondary brain injury that are dependent on immunologically active HMGB1 exposed on their surface. This finding provided new insight for the development of potential therapeutic targets and diagnostic biomarkers for TBI.

Sex and Racial/Ethnic Differences in Within-Stay Readmissions During Inpatient Rehabilitation Among Patients With Traumatic Brain Injury

OBJECTIVE

The aim of the study was to determine the association of sex and race/ethnicity with acute hospital readmissions ("within-stay readmissions") during inpatient rehabilitation facility care versus patients discharged home without a within-stay readmission among traumatic brain injury patients.

DESIGN

The study used a secondary analysis ( N = 210,440) of Uniform Data System for Medical Rehabilitation data using multiple logistic regression.

RESULTS

Within-stay readmissions occurred for 11.79% of female and 11.77% of male traumatic brain injury patients. Sex-specific models identified insurance, comorbidities, and complications factored differently in likelihood of within-stay readmissions among female than male patients but association of all other factors were similar per group. Within-stay readmissions differences were more pronounced by race/ethnicity: White, 11.63%; Black, 11.32%; Hispanic/Latino, 9.78%; and other, 10.61%. Descriptive bivariate analysis identified racial/ethnic patients with within-stay readmissions had greater days from traumatic brain injury to inpatient rehabilitation facility admission (White, 17.66; Black, 21.70; Hispanic/Latino, 23.81; other, 20.66) and lower admission cognitive and motor function. Factors differed across models predicting within-stay readmissions for race/ethnic groups; age, admission motor and cognitive function, complications, and length of stay were consistent across groups.

CONCLUSIONS

This study demonstrates disparities by race/ethnicity for inpatient rehabilitation facility within-stay readmissions among traumatic brain injury patients and factors predictive of this potentially preventable outcome by sex and race/ethnicity. Findings could inform care planning and quality improvement efforts for TBI patients.

Dynamic structures and emerging trends in the management of major trauma: A bibliometric analysis of publications between 2012 and 2021

Objective

Major trauma is currently a global public health issue with a massive impact on health at both the individual and population levels. However, there are limited bibliometric analyses on the management of major trauma. Thus, in this study we aimed to identify global research trends, dynamic structures, and scientific frontiers in the management of major trauma between 2012 and 2021.

Methods

We searched the Web of Science Core Collection to access articles and reviews concerning the management of major traumas and conducted a bibliometric analysis using CiteSpace.

Results

Overall, 2,585 studies were screened and published by 403 institutions from 110 countries/regions. The most productive country and institution in this field of research were the USA and Monash University, respectively. Rolf Lefering was the most prolific researcher and Holcomb JB had the most co-citations. Injury published the highest number of articles, and the Journal of Trauma was the most co-cited journal. A dual-map overlay of the literature showed that the articles of most publications were confined to the areas of medicine/medical/clinical and neurology/sports/ophthalmology. Document clustering indicated severe traumatic brain injury, traumatic coagulopathy, and resuscitative endovascular balloon occlusion as the recent hot topics. The most recent burst keywords were "trauma management," "neurocritical care," "injury severity," and "emergency medical services."

Conclusion

The dynamic structures and emerging trends in the management of major trauma were extensively analyzed using CiteSpace, a visualization software. Based on the analysis, the following research hotspots emerged: management of severe traumatic brain injury and massive hemorrhage, neurocritical care, injury severity, and emergency medical service. Our findings provide pertinent information for future research and contribute toward policy making in this field.

Risk Factors and Neurological Outcomes Associated With Circulatory Shock After Moderate-Severe Traumatic Brain Injury: A TRACK-TBI Study

BACKGROUND

Extracranial multisystem organ failure is a common sequela of severe traumatic brain injury (TBI). Risk factors for developing circulatory shock and long-term functional outcomes of this patient subset are poorly understood.

OBJECTIVE

To identify emergency department predictors of circulatory shock after moderate-severe TBI and examine long-term functional outcomes in patients with moderate-severe TBI who developed circulatory shock.

METHODS

We conducted a retrospective cohort study using the Transforming Clinical Research and Knowledge in TBI database for adult patients with moderate-severe TBI, defined as a Glasgow Coma Scale (GCS) score of <13 and stratified by the development of circulatory shock within 72 hours of hospital admission (Sequential Organ Failure Assessment score ≥2). Demographic and clinical data were assessed with descriptive statistics. A forward selection regression model examined risk factors for the development of circulatory shock. Functional outcomes were examined using multivariable regression models.

RESULTS

Of our moderate-severe TBI population (n = 407), 168 (41.2%) developed circulatory shock. Our predictive model suggested that race, computed tomography Rotterdam scores <3, GCS in the emergency department, and development of hypotension in the emergency department were associated with developing circulatory shock. Those who developed shock had less favorable 6-month functional outcomes measured by the 6-month GCS-Extended (odds ratio 0.36, P = .002) and 6-month Disability Rating Scale score (Diff. in means 3.86, P = .002) and a longer length of hospital stay (Diff. in means 11.0 days, P < .001).

CONCLUSION

We report potential risk factors for circulatory shock after moderate-severe TBI. Our study suggests that developing circulatory shock after moderate-severe TBI is associated with poor long-term functional outcomes.

Utilization of Brain Tissue Oxygenation Monitoring and Association with Mortality Following Severe Traumatic Brain Injury

BACKGROUND

The aim of this study was to describe the utilization patterns of brain tissue oxygen (PbtO₂) monitoring following severe traumatic brain injury (TBI) and determine associations with mortality, health care use, and pulmonary toxicity.

METHODS

We conducted a retrospective cohort study of patients from United States trauma centers participating in the American College of Surgeons National Trauma Databank between 2008 and 2016. We examined patients with severe TBI (defined by admission Glasgow Coma Scale score ≤ 8) over the age of 18 years who survived more than 24 h from admission and required intracranial pressure (ICP) monitoring. The primary exposure was PbtO₂ monitor placement. The primary outcome was hospital mortality, defined as death during the hospitalization or discharge to hospice. Secondary outcomes were examined to determine the association of PbtO₂ monitoring with health care use and pulmonary toxicity and included the following: (1) intensive care unit length of stay, (2) hospital length of stay, and (3) development of acute respiratory distress syndrome (ARDS). Regression analysis was used to assess differences in outcomes between patients exposed to PbtO₂ monitor placement and those without exposure by using propensity weighting to address selection bias due to the nonrandom allocation of treatment groups and patient dropout.

RESULTS

A total of 35,501 patients underwent placement of an ICP monitor. There were 1,346 (3.8%) patients who also underwent PbtO₂ monitor placement, with significant variation regarding calendar year and hospital. Patients who underwent placement of a PbtO₂ monitor had a crude in-hospital mortality of 31.1%, compared with 33.5% in patients who only underwent placement of an ICP monitor (adjusted risk ratio 0.84, 95% confidence interval 0.76-0.93). The development of the ARDS was comparable between patients who underwent placement of a PbtO₂ monitor and patients who only underwent placement of an ICP monitor (9.2% vs. 9.8%, adjusted risk ratio 0.89, 95% confidence interval 0.73-1.09).

CONCLUSIONS

PbtO₂ monitor utilization varied widely throughout the study period by calendar year and hospital. PbtO₂ monitoring in addition to ICP monitoring, compared with ICP monitoring alone, was associated with a decreased in-hospital mortality, a longer length of stay, and a similar risk of ARDS. These findings provide further guidance for clinicians caring for patients with severe TBI while awaiting completion of further randomized controlled trials.

Histological and immunohistochemical study of brain damage in traumatic brain injuries in children, depending on the survival period

Numerous studies showed that, at present, traumatic brain injury (TBI) is one of the main causes of death in young adults, but also a main cause of disabilities at all ages. For these reasons, TBI are continuously investigated. In our study, we evaluated the histopathological (HP) and immunohistochemical (IHC) changes that occurred in the brain in underage patients after a severe TBI depending on the survival period. We histopathologically and immunohistochemically analyzed a number of 22 cases of children, deceased in Dolj County, Romania, following some severe TBI, undergoing autopsy within the Institute of Forensic Medicine in Craiova between 2015-2020. Patients were divided into three groups depending on the survival period, namely: (i) patients who died during the first 24 hours of the accident; (ii) patients who died after seven days of survival; (iii) patients who died after 15 days of survival. Microscopic examinations of the brain fragments, collected during the necropsy examination, showed that the traumatic agent caused primary injuries in all brain structures (cerebral parenchyma, meninges, blood vessels). However, HP injuries ranged in size and intensity from one area to another of the brain. In patients with a longer survival period, there was observed the presence of smaller primary injuries and larger secondary injuries. There was also observed a growth in the number of meningo-cerebral microscopic injuries, depending on the increase of the survival period.

Mortality risk stratification in isolated severe traumatic brain injury using the revised cardiac risk index

PURPOSE

Traumatic brain injury (TBI) continues to be a significant cause of mortality and morbidity worldwide. As cardiovascular events are among the most common extracranial causes of death after a severe TBI, the Revised Cardiac Risk Index (RCRI) could potentially aid in the risk stratification of this patient population. This investigation aimed to determine the association between the RCRI and in-hospital deaths among isolated severe TBI patients.

METHODS

All adult patients registered in the TQIP database between 2013 and 2017 who suffered an isolated severe TBI, defined as a head AIS ≥ 3 with an AIS ≤ 1 in all other body regions, were included. Patients were excluded if they had a head AIS of 6. The association between different RCRI scores (0, 1, 2, 3, ≥ 4) and in-hospital mortality was analyzed using a Poisson regression model with robust standard errors while adjusting for potential confounders, with RCRI 0 as the reference.

RESULTS

259,399 patients met the study's inclusion criteria. RCRI 2 was associated with a 6% increase in mortality risk [adjusted IRR (95% CI) 1.06 (1.01-1.12), p = 0.027], RCRI 3 was associated with a 17% increased risk of mortality [adjusted IRR (95% CI) 1.17 (1.05-1.31), p = 0.004], and RCRI ≥ 4 was associated with a 46% increased risk of in-hospital mortality [adjusted IRR(95% CI) 1.46 (1.11-1.90), p = 0.006], compared to RCRI 0.

CONCLUSION

An elevated RCRI ≥ 2 is significantly associated with an increased risk of in-hospital mortality among patients with an isolated severe traumatic brain injury. The simplicity and bedside applicability of the index makes it an attractive choice for risk stratification in this patient population.

Effect of Mild Hypothermia after Craniotomy on the Function of Related Organs in Patients with Traumatic Brain Injury

OBJECTIVE

To investigate the effect of mild hypothermia after craniotomy on the function of related organs in patients with traumatic brain injury.

METHOD

A total of 240 patients with craniocerebral injury from January 2017 to December 2020 were retrospectively analyzed. Patients were randomly divided into a control group and an experimental group, with 120 cases in each group. The control group was treated with craniotomy decompression, and the experimental group was treated with early mild hypothermia based on craniotomy decompression. Patients' venous blood was collected before operation (T 0), at the end of operation (T 1), 24 h after operation (T 2), and 2 weeks after operation (T 3) to detect the serum levels of the beta-subunit of S100 protein (S100-β); soluble growth stimulation expressed gene 2 (sST2), neutrophil gelatinase-associated lipocalin (NGAL), and interleukin 6 (IL-6). The prognostic effect was evaluated after 2 weeks of treatment.

RESULTS

After mild hypothermia treatment after craniotomy and decompression, the patients' serum S100-β, sST2, NGAL, and IL-6 levels at different time points were significantly lower than the control group, and the total effective rate was higher than that of the control group.

CONCLUSION

The treatment of mild hypothermia after craniotomy can reduce the related organs function damage indicators and inflammatory stress response, thus improving clinical efficacy and prognosis.