Early detection of nonneurologic organ failure in patients with severe traumatic brain injury: Multiple organ dysfunction score or sequential organ failure assessment?

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.

Risk factors of deterioration in patients of head injury with non-operative management on first neurosurgical consultation

Objectives

In most of the emergency trauma intensive care units (ICUs) of India, neurosurgical opinion is sought for patients presenting with head trauma after earliest possible resuscitation to determine the further line of management. This study aimed to identify common risk factors, leading to neurological deterioration in conservatively managed patients of traumatic brain injury (TBI).

Materials and Methods

This retrospective study analyzed patients admitted with acute TBI and traumatic intracranial hematoma under emergency trauma care ICU who did not require neurosurgical operation within 48 h of trauma. The recorded data were analyzed to determine the predictors of neurological deterioration using univariate and binary logistic regression analysis in SPSS-16 software.

Results

Medical records of consecutive 275 patients of acute TBI presenting to the emergency department were studied. One hundred and ninety-three patients were afflicted with mild TBI (70.18%), 49 patients had moderate TBI (17.81%), and 33 had severe TBI (12%). In the outcome, 74.54% of patients were discharged, and operative decision was made on 6.18% of patients and 19.27% died. Severe TBI is the independent predictor of neurological deterioration during their stay in ICU. Progressive hemorrhagic injury (PHI) showed neurological deterioration in 86.5% of patients. Systemic inflammatory response syndrome (SIRS) was present in 93.5% of patients who had deteriorated neurologically. Dyselectrolytemia was the biochemical derangements seen in 24.36% of cases.

Conclusion

This study revealed severe TBI, PHI, and SIRS to be strong and independent risk factors of neurological deterioration.

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.

Association of Early Multiple Organ Dysfunction With Clinical and Functional Outcomes Over the Year Following Traumatic Brain Injury: A Transforming Research and Clinical Knowledge in Traumatic Brain Injury Study

OBJECTIVES

Traumatic brain injury is a leading cause of death and disability in the United States. While the impact of early multiple organ dysfunction syndrome has been studied in many critical care paradigms, the clinical impact of early multiple organ dysfunction syndrome in traumatic brain injury is poorly understood. We examined the incidence and impact of early multiple organ dysfunction syndrome on clinical, functional, and disability outcomes over the year following traumatic brain injury.

DESIGN

Retrospective cohort study.

SETTING

Patients enrolled in the Transforming Clinical Research and Knowledge in Traumatic Brain Injury study, an 18-center prospective cohort study of traumatic brain injury patients evaluated in participating level 1 trauma centers.

SUBJECTS

Adult (age > 17 yr) patients with moderate-severe traumatic brain injury (Glasgow Coma Scale < 13). We excluded patients with major extracranial injury (Abbreviated Injury Scale score ≥ 3).

INTERVENTIONS

Development of early multiple organ dysfunction syndrome, defined as a maximum modified Sequential Organ Failure Assessment score greater than 7 during the initial 72 hours following admission.

MEASUREMENTS AND MAIN RESULTS

The main outcomes were: hospital mortality, length of stay, 6-month functional and disability domains (Glasgow Outcome Scale-Extended and Disability Rating Scale), and 1-year mortality. Secondary outcomes included: ICU length of stay, 3-month Glasgow Outcome Scale-Extended, 3-month Disability Rating Scale, 1-year Glasgow Outcome Scale-Extended, and 1-year Disability Rating Scale. We examined 373 subjects with moderate-severe traumatic brain injury. The mean (sd) Glasgow Coma Scale in the emergency department was 5.8 (3.2), with 280 subjects (75%) classified as severe traumatic brain injury (Glasgow Coma Scale 3-8). Among subjects with moderate-severe traumatic brain injury, 252 (68%) developed early multiple organ dysfunction syndrome. Subjects that developed early multiple organ dysfunction syndrome had a 75% decreased odds of a favorable outcome (Glasgow Outcome Scale-Extended 5-8) at 6 months (adjusted odds ratio, 0.25; 95% CI, 0.12-0.51) and increased disability (higher Disability Rating Scale score) at 6 months (adjusted mean difference, 2.04; 95% CI, 0.92-3.17). Subjects that developed early multiple organ dysfunction syndrome experienced an increased hospital length of stay (adjusted mean difference, 11.4 d; 95% CI, 7.1-15.8), with a nonsignificantly decreased survival to hospital discharge (odds ratio, 0.47; 95% CI, 0.18-1.2).

CONCLUSIONS

Early multiple organ dysfunction following moderate-severe traumatic brain injury is common and independently impacts multiple domains (mortality, function, and disability) over the year following injury. Further research is necessary to understand underlying mechanisms, improve early recognition, and optimize management strategies.

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

Traumatic brain injury (TBI) is a major global health problem and a major contributor to morbidity and mortality following multisystem trauma. Extracranial organ dysfunction is common after severe TBI and significantly impacts clinical care and outcomes following injury. Despite this, extracranial organ dysfunction remains an understudied topic compared with organ dysfunction in other critical care paradigms. In this review, we will: 1) summarize the epidemiology of extracranial multiorgan dysfunction following severe TBI; 2) examine relevant mechanisms that may be involved in the development of multi-organ dysfunction following severe TBI; and 3) discuss clinical management strategies to care for these complex patients.

Association of Severe Acute Kidney Injury with Mortality and Healthcare Utilization Following Isolated Traumatic Brain Injury

BACKGROUND/OBJECTIVE

Traumatic brain injury (TBI) is a leading cause of morbidity, mortality, and disability in the USA. While cardiopulmonary dysfunction can result in poor outcomes following severe TBI, the impact of acute kidney injury (AKI) is poorly understood. We examined the association of severe AKI with hospital mortality and healthcare utilization following isolate severe TBI.

METHODS

We conducted a retrospective cohort study using the National Trauma Data Bank from 2007 to 2014. We identified a cohort of adult patients with isolated severe TBI and described the incidence of severe AKI, corresponding to Acute Kidney Injury Network stage 3 disease or greater. We examined the association of severe AKI with the primary outcome of hospital mortality using multivariable logistic regression models. In secondary analyses, we examined the association of severe AKI with dialysis catheter placement, tracheostomy and gastrostomy utilization, and hospital length of stay.

RESULTS

There were 37,851 patients who experienced isolated severe TBI during the study period. Among these patients, 787 (2.1%) experienced severe (Stage 3 or greater) AKI. In multivariable models, the development of severe AKI in the hospital was associated with in-hospital mortality (OR 2.03, 95% CI 1.64-2.52), need for tracheostomy (OR 2.10, 95% CI 1.52-2.89), PEG tube placement (OR 1.88, 95% CI 1.45-2.45), and increased hospital length of stay (p < 0.001).

CONCLUSIONS

The overall incidence of severe AKI is relatively low (2.1%), but is associated with increased mortality and multiple markers of increased healthcare utilization following severe TBI.

The impact of non-neurological organ dysfunction on outcomes in severe isolated traumatic brain injury

INTRODUCTION

Organ dysfunction following traumatic brain injury (TBI) is common and has been associated with unpredictable outcomes. The aim of our study is to describe the incidence of non-neurological organ dysfunction (NNOD) and its impact on outcomes in patients with severe TBI admitted to our intensive care unit (ICU).

METHODS

We performed a 3-year (2015-2017) review of our Level 1 trauma center's prospectively maintained TBI database and included all adult (age ≥18y) patients with isolated severe TBI (head abbreviated injury severity (AIS) ≥3 and other AIS <3) and an ICU stay >48 hours. Organ dysfunction (OD) was measured by multiple organ dysfunction scores. Organ system failure was defined as a non-neurological component score of ≥3 on any day during the ICU stay. Outcomes measured were the incidence of NNOD and its effect on outcomes. Multivariate regression analysis was performed.

RESULTS

A total of 285 patients were included. The mean age was 48 ± 22 years, 72% were males, median [IQR] Glasgow Coma Scale (GCS) was 8[5-10], and median Injury Severity Score (ISS) was 17[10-26]. Epidural hematoma was the most common intracranial hemorrhage (49%) followed by subdural hematoma (46%). The overall incidence of NNOD was 33%, with the most common dysfunctional organ system being the respiratory (23%) followed by the cardiovascular (12%) and hepatic system (8%). The overall in-hospital mortality rate was 19% (NNOD:36% vs. No-NNOD:9%, p< 0.01). On regression analysis, NNOD was associated with higher in-hospital mortality (aOR: 2.0 [1.6-2.7]), discharge to skilled nursing facility (SNF) (aOR: 1.8 [1.4-2.2]), and Glasgow Outcome Scale-Extended (GOS-E) ≤4 (OR: 1.7 [1.3-2.3]) and p-values <0.01.

CONCLUSION

One in every three isolated severe TBI patients develop NNOD. NNOD is independently associated with worse outcomes. Understanding the mechanisms associated with NNOD in the setting of TBI may promote prevention practices and improve outcomes in TBI.

LEVEL OF EVIDENCE

Prognostic, level III.

Non-neurologic organ dysfunction plays a major role in predicting outcomes in pediatric traumatic brain injury

BACKGROUND

Nonneurological organ dysfunction (NNOD) occurs after traumatic brain injury (TBI) and is associated with mortality. The aim of our study was to evaluate the prevalence of NNOD and its association with outcomes in pediatric patients with TBI. We hypothesized that NNOD is associated with worse outcomes in pediatric patients with severe TBI.

METHODS

We performed a 4-year (2013-16) analysis of our prospectively maintained TBI database. All patients (age < 18) with an isolated-severe TBI (head-abbreviated injury scale: AIS ≥ 3 & extracranial-AIS < 3) were included. NNOD was measured using the pediatric multiple organ dysfunction (P-MOD) score. Outcomes were in-hospital mortality, Glasgow Outcome Scale-Extended (GOS-E), and adverse discharge disposition: rehabilitation or skilled nursing facility (SNF). Regression analysis was performed.

RESULTS

We analyzed 292 patients. Mean age was 11 ± 6 years, 57% were male and the mortality rate was 18.1%. The incidence of NNOD was 35%. The most common dysfunctional organ system was the respiratory (25%) followed by the cardiovascular (12%). On regression analysis, the presence of at least one NNOD was independently associated with in-hospital mortality (OR 2.1 [1.7-2.9]; p < 0.01), low GOS-E (OR 1.8 [1.5-2.3]; p < 0.01), and SNF disposition (OR 1.7 [1.2-2.1]; p < 0.01).

CONCLUSION

NNOD develops in one of every three severe TBI pediatric patients and is independently associated with adverse outcomes. Identification of NNOD in pediatric TBI and focusing on management of NNOD could improve outcomes.

LEVEL OF EVIDENCE

III Prognostic.

Ghrelin alleviates traumatic brain injury-induced acute lung injury through pyroptosis/NF-κB pathway

Acute lung injury (ALI) is one of the severe complications in patients with traumatic brain injury (TBI), contributing to the high mortality. Ghrelin has protective effects against various inflammatory diseases, but the effects of Ghrelin on TBI-induced ALI and its mechanisms remain unknown. In this study, Ghrelin administration was performed on the mice with TBI, then histological change in cortex and lung tissues, lung vascular permeability and macrophage number in bronchoalveolar lavage fluid (BALF) were examined, respectively. Simultaneously, the alterations of proinflammatory factors and pyroptosis-related proteins in lung tissues were detected. As a result, TBI-induced ALI was ameliorated after Ghrelin treatment, which was demonstrated by improved histology, reduced lung vascular permeability, and peripheral macrophage number. Furthermore, Ghrelin decreased the mRNA levels of proinflammatory factors (IL-1β, IL-6, TNF-α and IL-18), the protein levels of pyroptosis-related proteins (NLRP3, Caspase1-P20, HMGB1 and Gasdermin D), and the phosphorylation levels of NF-κB in lung tissues. These results showed that Ghrelin attenuating TBI-induced ALI might be via ameliorating inflammasome-induced pyroptosis by blocking NF-κB signal, which are important for the prevention and treatment of TBI-induced ALI.

Human Lung Cell Pyroptosis Following Traumatic Brain Injury

Approximately 30% of traumatic brain injured patients suffer from acute lung injury or acute respiratory distress syndrome. Our previous work revealed that extracellular vesicle (EV)-mediated inflammasome signaling plays a crucial role in the pathophysiology of traumatic brain injury (TBI)-induced lung injury. Here, serum-derived EVs from severe TBI patients were analyzed for particle size, concentration, origin, and levels of the inflammasome component, an apoptosis-associated speck-like protein containing a caspase-recruiting domain (ASC). Serum ASC levels were analyzed from EV obtained from patients that presented lung injury after TBI and compared them to EV obtained from patients that did not show any signs of lung injury. EVs were co-cultured with lung human microvascular endothelial cells (HMVEC-L) to evaluate inflammasome activation and endothelial cell pyroptosis. TBI patients had a significant increase in the number of serum-derived EVs and levels of ASC. Severe TBI patients with lung injury had a significantly higher level of ASC in serum and serum-derived EVs compared to individuals without lung injury. Only EVs isolated from head trauma patients with gunshot wounds were of neural origin. Delivery of serum-derived EVs to HMVEC-L activated the inflammasome and resulted in endothelial cell pyroptosis. Thus, serum-derived EVs and inflammasome proteins play a critical role in the pathogenesis of TBI-induced lung injury, supporting activation of an EV-mediated neural-respiratory inflammasome axis in TBI-induced lung injury.

Functional Outcomes 6 Months After Severe Traumatic Brain Injury Following Admission Into Intensive Care Unit: A Cohort Study in Two Tertiary Hospitals

Severe traumatic brain injury (TBI) survivors show physical and functional improvements but continue to have cognitive and psychosocial problems throughout recovery. However, the functional outcome of severe TBI in Malaysia is unknown. The objective of this study is to measure the functional outcomes of severe TBI within 6 months post-injury. A cohort study was done on 33 severe TBI survivors. The Glasgow Outcome Scale-Extended (GOSE) was used in this study. The mean age of the participants was 31.79 years (range: 16-73 years). The logistic regression model was statistically significant, χ²(5, N = 33) = 29.09, p < .001. The length of stay (LOS) in incentive care unit (p = .049, odds ratio = 6.062) and duration on ventilator (p = .048, odds ratio = 0.083) were good predictors of the functional outcomes. Future research should focus on larger sample size of severe TBI in Malaysia.