Acute Management of Traumatic Brain Injury

Systemic Inflammatory Effect of Hypobaria During Aeromedical Evacuation after Porcine Traumatic Brain Injury

BACKGROUND

Traumatic brain injury (TBI)-related morbidity is caused largely by secondary injury resulting from hypoxia, excessive sympathetic drive, and uncontrolled inflammation. Aeromedical evacuation (AE) is used by the military for transport of wounded soldiers to higher levels of care. We hypothesized that the hypobaric, hypoxic conditions of AE may exacerbate uncontrolled inflammation after TBI that could contribute to more severe TBI-related secondary injury.

STUDY DESIGN

Thirty-six female pigs were used to test TBI vs Sham TBI, hypoxia vs normoxia, and hypobaria vs ground conditions. TBI was induced by controlled cortical injury, hypobaric conditions of 12,000 ft were established in an altitude chamber, and hypoxic exposure was titrated to 85% SpO 2 while at altitude. Serum cytokines, ubiquitin C-terminal hydrolase L1, and TBI biomarkers were analyzed via ELISA. Gross analysis and staining of cortex and hippocampus tissue was completed for glial fibrillary acidic protein and phosphorylated tau.

RESULTS

Serum interleukin-1β, interleukin-6, and tumor necrosis factor-α were significantly elevated after TBI in pigs exposed to altitude-induced hypobaria/hypoxia, as well as hypobaria alone, compared with ground level/normoxia. No difference in TBI biomarkers after TBI or hypobaric, hypoxic exposure was noted. No difference in brain tissue glial fibrillary acidic protein or phosphorylated tau when comparing the most different conditions of Sham TBI + ground or normoxia with the TBI + hypobaria/hypoxia group was noted.

CONCLUSIONS

The hypobaric environment of AE induces systemic inflammation after TBI. Severe inflammation may play a role in exacerbating secondary injury associated with TBI and contribute to worse neurocognitive outcomes. Measures should be taken to minimize barometric and oxygenation changes during AE after TBI.

Assessment of traumatic brain injury treatment guided by continuous monitoring of intracranial pressure and brain tissue oxygen partial pressure: A single-center pilot study

Severe traumatic brain injury (TBI) is a leading cause of death and disability. Monitoring intracranial pressure (ICP) is recommended, but the data on the outcomes are conflicting. Adding continuous brain tissue oxygen partial pressure (PbtO2) monitoring may have some benefit but the OXY-TC suggested it did not improve 6-month neurological outcomes. This single-center pilot randomized controlled study aimed to evaluate whether adding PbtO2 monitoring was feasible and could improve the prognosis of severe TBI. The participants were randomized into either an ICP alone or an ICP + PbtO2 group for 7 days, with treatment protocols based on existing guidelines. Clinical parameters were collected hourly. The primary outcome was the feasibility of using PbtO2 monitoring. The secondary outcomes were 6-month survival, analyzed by the log-rank test, the 3- and 6-month Glasgow Outcome Scale (GOS) scores, compared between groups by chi-squared test. Seventy patients were included (36 ICP, 34 ICP + PbtO2). The ICP + PbtO2 group had lower mean daily ICP (13.4 vs. 18.2 mmHg, P = 0.0024) and higher mean daily cerebral perfusion pressure (82.1 vs. 74.5 mmHg, P = 0.0055). The ICP + PbtO2 group had higher 6-month survival (79.4 % vs. 55.6 %, P = 0.0337) and more favorable outcomes at 3 months (67.6 % vs. 38.9 %, P = 0.0160) and 6 months (70.6 % vs. 41.7 %, P = 0.0149). Adding PbtO2 monitoring to ICP monitoring is feasible in patients with severe TBI and could maybe improve the intermediate-term outcomes. The results will serve to design larger trials.

Vasospasm in traumatic brain injury

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality in young individuals. Management of TBI is complex and aims to prevent secondary injury and optimise conditions for neurological recovery. Vasospasm is a possible complication of TBI, and its significance is unknown. Its incidence is underestimated and there are currently no preventive or therapeutic approaches with proven efficacy. The occurrence of vasospasm contributes to secondary brain injury and worsens prognosis. The diagnosis of vasospasm in TBI is challenging due to the difficulty in perceiving neurological deterioration in these patients. We present a case of a young patient admitted to the neurocritical care unit following TBI. He presented a partial neurological recovery, followed by clinical deterioration and persistent coma. The diagnosis of extensive ischaemic lesions due to severe vasospasm was established. Suspicion of vasospasm and timely screening, particularly in high-risk patients, may improve survival and outcomes in TBI.

Metabolic Pathophysiology of Cortical Spreading Depression: A Review

Cortical spreading depression (CSD) is an electrophysiologic pathological state in which a wave of depolarization in the cerebral cortex is followed by the suppression of spontaneous neuronal activity. This transient spread of neuronal depolarization on the surface of the cortex is the hallmark of CSD. Numerous investigations have demonstrated that transmembrane ion transport, astrocytic ion clearing and fatigue, glucose metabolism, the presence of certain genetic markers, point mutations, and the expression of the enzyme responsible for the production of various arachidonic acid derivatives that participate in the inflammatory response, namely, cyclooxygenase (COX), all influence CSD. Here, we explore the associations between CSD occurrence in the cortex and various factors, including how CSD is related to migraines, how the glucose state affects CSD, the effect of TBI and its relationship with CSD and glucose metabolism, how different markers can be measured to determine the severity of CSD, and possible connections to oligemia, orexin, and leptin.

Effectiveness of hypertonic saline infusion in management of traumatic brain injury: an updated systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

This study aimed to find out the efficacy of using Hypertonic saline solution (HSS) over mannitol in the management of TBI by comparing their performance in improving different outcomes.

METHODS

Electronic databases were searched for randomized controlled trials (RCTs) assessing the impact of HSS vs. mannitol on ICP in patients who suffered TBI. Outcomes of interest were mortality, neurologic functional outcomes, risk ratio (RR) of successful ICP treatment, reduction in ICP after 30-60 and 90-120 min, improvement in cerebral perfusion pressure (CPP) at 30-60 and 90-120 min, and also treatment failure. Evaluations were reported as RR or mean difference (MD) with 95% confidence intervals (CIs) using weighted random-effects models.

RESULTS

The analysis included 624 patients from 15 RCTs. HSS infusion had a significant impact on the improvement of CPP at 30-60 min [MD = 5.54, 95% CI (3.04, 8.03),p < 0.001] compared to mannitol. However, results yielded no significant difference between HSS and mannitol in terms of mortality, neurologic functional outcomes, successful ICP treatment, reduction in ICP after 30-60 min and 90-120 min, improvement in CPP at 90-120 min, and treatment failure.

CONCLUSION

HSS and mannitol are both effective treatments for elevated ICP due to TBI. However, further research is required to derive a better comparison.

Multicenter Study Examining Temporal Trends in Traumatic Intracranial Hemorrhage Over Six Years Using Joinpoint Regression

The aging US population has altered the epidemiology of traumatic injury, but there are few studies examining changing patterns of traumatic intracranial hemorrhage (tICH). We examined temporal changes in incidence, demographics, severity, management, and outcomes of tICH among trauma admissions at six US Level I trauma centers over 6 years (July 1, 2016-June 30, 2022). Patients with tICH (subdural, epidural, subarachnoid, and intracerebral hemorrhage) were identified by 10th revision of the International Statistical Classification of Diseases diagnosis codes. Temporal trends were examined over 12 six-month intervals using joinpoint regression and reported as biannual percent change (BPC); models without joinpoints are described as linear trends over time. There were 67,514 trauma admissions over 6 years and 11,935 (17.7%) patients had a tICH. The proportion of tICH injuries significantly increased 2.6% biannually from July 2016 to July 2019 (BPC = 2.6, p = 0.04), then leveled off through June 2022 (BPC = -0.9, p = 0.19). Similarly, the proportion of geriatric patients (≥65 years old) increased 2.4% biannually from July 2016 to July 2019 (BPC = 2.4, p = 0.001) as did injuries due to falls (BPC = 2.2, p = 0.01). Three of the four most prevalent comorbidities significantly increased: hypertension linearly increased 2.1% biannually, functional dependence increased 25.5% biannually through June 2019, and chronic anticoagulant use increased 19.0% biannually through June 2019 and then 3.1% thereafter. There were no trends in the rates of neurosurgical intervention (BPC = -0.89, p = 0.40), ED Glasgow coma score 3-8 (BPC = -0.4, p = 0.77), or presence of severe extracranial injuries (BPC = -0.7, p = 0.45). In-hospital mortality linearly declined 2.6% biannually (BPC = 2.6, p = 0.05); however, there was a 10.3% biannual linear increase in discharge to hospice care (BPC = 10.3, p < 0.001). These results demonstrate the incidence of tICH admissions is temporally increasing, and the population is growing older with more comorbidities and injuries from falls. Yet, traumatic brain injury severity and neurosurgical management are unchanged. The shift from in-patient death to hospice care suggests an increased need for palliative care services.

Connecting cellular mechanisms and extracellular vesicle cargo in traumatic brain injury

Traumatic brain injury is followed by a cascade of dynamic and complex events occurring at the cellular level. These events include: diffuse axonal injury, neuronal cell death, blood-brain barrier break down, glial activation and neuroinflammation, edema, ischemia, vascular injury, energy failure, and peripheral immune cell infiltration. The timing of these events post injury has been linked to injury severity and functional outcome. Extracellular vesicles are membrane bound secretory vesicles that contain markers and cargo pertaining to their cell of origin and can cross the blood-brain barrier. These qualities make extracellular vesicles intriguing candidates for a liquid biopsy into the pathophysiologic changes occurring at the cellular level post traumatic brain injury. Herein, we review the most commonly reported cargo changes in extracellular vesicles from clinical traumatic brain injury samples. We then use knowledge from animal and in vitro models to help infer what these changes may indicate regrading cellular responses post traumatic brain injury. Future research should prioritize labeling extracellular vesicles with markers for distinct cell types across a range of timepoints post traumatic brain injury.

Assessing the Predictive Utility of the C-Reactive Protein-to-Lymphocyte Ratio for Mortality in Isolated Traumatic Brain Injury: A Single-Center Retrospective Analysis

Introduction: Early identification of high-risk traumatic brain injury (TBI) patients is crucial for optimizing treatment strategies and improving outcomes. The C-reactive protein-to-lymphocyte ratio (CLR) reflects systemic immunology and inflammation function and serves as a new biomarker for patient stratification. This study aimed to assess the predictive value of the CLR for mortality in patients with isolated moderate to severe TBI. Methods: A retrospective analysis of trauma registry data from 2009 to 2022 was conducted, including 1641 adult patients with isolated moderate to severe TBI. Patient demographics, the CLR, injury characteristics, and outcomes were compared between deceased and surviving patients. Univariate and multivariate analyses were performed to identify mortality risk factors. The optimal CLR cut-off value for predicting mortality was determined using receiver operating characteristic (ROC) curve analysis. Results: The CLR was significantly higher in deceased patients compared to survivors (60.1 vs. 33.9, p < 0.001). The optimal CLR cut-off value for predicting mortality was 54.5, with a sensitivity of 0.328 and a specificity of 0.812. The area under the ROC curve was 0.566, indicating poor discriminative ability. In the multivariate analysis, the CLR was not a significant independent predictor of mortality (OR 1.03, p = 0.051). After propensity score matching to attenuate the difference in baseline characteristics, including sex, age, comorbidities, conscious level, and injury severity, the high-CLR group (CLR ≥ 54.5) did not have significantly higher mortality compared to the low-CLR group (CLR < 54.5). Conclusion: While the CLR was associated with mortality in TBI patients, it demonstrated poor discriminative ability as a standalone predictor. The association between a high CLR and worse outcomes may be primarily due to other baseline patient and injury characteristics, rather than the CLR itself.

Development and validation of a clinical nomogram for predicting in-hospital mortality in patients with traumatic brain injury prehospital: A retrospective study

Objective

Traumatic brain injury (TBI) is among the leading causes of death and disability globally. Identifying and assessing the risk of in-hospital mortality in traumatic brain injury patients at an early stage is challenging. This study aimed to develop a model for predicting in-hospital mortality in TBI patients using prehospital data from China.

Methods

We retrospectively included traumatic brain injury patients who sustained injuries due to external forces and were treated by pre-hospital emergency medical services (EMS) at a tertiary hospital. Data from the pre-hospital emergency database were analyzed, including demographics, trauma mechanisms, comorbidities, vital signs, clinical symptoms, and trauma scores. Eligible patients were randomly divided into a training set (241 cases) and a validation set (104 cases) at a 7:3 ratio. Least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression were employed to identify independent risk factors. Analyzed the discrimination, calibration, and net benefit of the nomogram across both groups.

Results

17.40 % (42/241) of TBI patients died in the hospital in the training set, while 18.30 % (19/104) in the validation set. After analysis, chest trauma (odds ratio [OR] = 4.556, 95 % confidence interval [CI] = 1.861-11.152, P = 0.001), vomiting (OR = 2.944, 95%CI = 1.194-7.258, P = 0.019), systolic blood pressure (OR = 0.939, 95%CI = 0.913-0.966, P < 0.001), SpO2 (OR = 0.778, 95%CI = 0.688-0.881, P < 0.001), and heart rate (OR = 1.046, 95%CI = 1.015-1.078, P = 0.003) were identified as independent risk factors for in-hospital mortality in TBI patients. The nomogram based on the five factors demonstrated well-predictive power, with an area under the curve (AUC) of 0.881 in the training set and 0.866 in the validation set. The calibration curve and decision curve analysis showed that the predictive model exhibited good consistency and covered a wide range of threshold probabilities in both sets.

Conclusion

The nomogram based on prehospital data demonstrated well-predictive performance for in-hospital mortality in TBI patients, helping prehospital emergency physicians identify and assess severe TBI patients earlier, thereby improving the efficiency of prehospital emergency care.

Gastrointestinal bleeding following traumatic brain injury: A clinical study on predisposing factors and outcomes

Background

Traumatic brain injury (TBI) is one of the most common causes of death and disability worldwide. Stress ulcers are common in critically ill patients and can lead to life-threatening gastrointestinal bleeding (GIB). This study investigates the impact of predisposing factors on GIB and outcomes of TBI patients.

Methods

This retrospective cohort study included TBI patients admitted between February 2019 and November 2021. Patients' demographic information and clinical characteristics were collected and divided into Post-TBI GIB and No-GIB groups. During clinical follow-up, the Glasgow Outcome Score (GOS) and mortality were assessed. The correlation between predisposing factors and GIB was investigated.

Results

Out of 164 eligible patients, 66.5% were males, and the mean age was 31.38 ± 13.44 years. There was a higher rate of severe TBIs (p<0.001), intra-axial lesions (P=0.014), hypotension at admission (p<0.001), and concurrent coagulopathies (p<0.001) in the Post-TBI GIB group compared to the No-GIB group. In contrast, the Glasgow Coma Scale (GCS) level upon admission and discharge (p<0.001) and serum hemoglobin level at admission (p<0.001) were lower in the Post-TBI GIB group than in the other group. Moreover, primary GCS (P=0.017) and hypotension at admission (P=0.009), spinal injury (P=0.028), and intra-axial brain injury (P=0.018) were independently associated with GIB in TBI patients.

Conclusion

Primary GCS and hypotension at admission, spinal injury, and intra-axial brain injury are independent predictors for GIB in TBI patients. The presence of GIB in TBI patients is associated with worse neurological outcomes as assessed by GOS at approximately 18 months.

Unraveling the molecular complexity: Wtap/Ythdf1 and Lcn2 in novel traumatic brain injury secondary injury mechanisms

The primary aim of this research was to explore the functions of Wtap and Ythdf1 in regulating neuronal Lipocalin-2 (Lcn2) through m6A modification in traumatic brain injury (TBI). By employing transcriptome sequencing and enrichment analysis, we identified the Wtap/Ythdf1-mediated Lcn2 m6A modification pathway as crucial in TBI. In our in vitro experiments using primary cortical neurons, knockout of Wtap and Ythdf1 led to the inhibition of Lcn2 m6A modification, resulting in reduced neuronal death and inflammation. Furthermore, overexpression of Lcn2 in cortical neurons induced the activation of reactive astrocytes and M1-like microglial cells, causing neuronal apoptosis. In vivo experiments confirmed the activation of reactive astrocytes and microglial cells in TBI and importantly demonstrated that Wtap knockdown improved neuroinflammation and functional impairment. These findings underscore the significance of Wtap/Ythdf1-mediated Lcn2 regulation in TBI secondary injury and suggest potential therapeutic implications for combating TBI-induced neuroinflammation and neuronal damage.

The Levels of Biomarkers Interleukin 1 (IL-1) and Brain-Derived Neurotrophic Factor (BDNF) in Non-Invasive Conventional Rehabilitation and Robotic Rehabilitation Among Brain Injury Patients: A Narrative Review

Acquired brain injury (ABI) is becoming increasingly common in Malaysia as a result of a rise in both strokes and accidents. The present review aims to explore the levels of serum inflammatory markers of interleukin-1 (IL-1) and brain-derived neurotrophic factor (BDNF) following conventional and robotic rehabilitation regimes among ABI patients and the association between serum biomarkers with the Medical Research Council (MRC) scale for muscle strength. Online databases, namely ScienceDirect, PubMed, and Google Scholar were utilized by using search terms such as 'Definition of brain injury', 'Epidemiology of brain injury', 'Interleukin-1 in stroke', 'BDNF in stroke', 'Interleukin-1 in traumatic brain injury', 'BDNF in traumatic brain injury', 'Interleukin-1 level and robotic rehabilitation', 'BDNF and robotic rehabilitation', 'Interleukin-1 level and neurorehabilitation', and 'BDNF and neurorehabilitation'. All types of articles with different levels of evidence were included along with other relevant review articles. Articles that were not in English and were not available in the full text were excluded. The review identifies similar and no significant improvement in the treatment between conventional rehabilitation and robotic rehabilitation concerning serum biomarkers IL-1 and BDNF. This review also identifies that muscle strength and endurance training improved the level of serum BDNF in brain injury patients. Therefore, this review provides evidence of the levels of IL-1 and BDNF in non-invasive conventional rehabilitation and robotic rehabilitation among brain injury patients, as well as their relation with the MRC scale, to give a good functional outcome that will enhance the quality of life of these groups of individuals.

Activation of GPER-1 Attenuates Traumatic Brain Injury-Induced Neurological Impairments in Mice

This study aimed to investigate the effects of G1-activated G protein-coupled estrogen receptor 1 (GPER1) on neurological impairments and neuroinflammation in traumatic brain injury (TBI) mice. The controlled cortical impingement (CCI) method was used to establish the TBI model. The mice were subjected to ovariectomy (OVX) for two weeks prior to modeling. GPER1 agonist G1 was administered by intracerebroventricular injection. Brain tissue water content was detected by wet/dry method, and blood-brain barrier damage was detected by Evans blue extravasation. The neurological impairments in mice were evaluated by open field test, Y-maze test, nest-building test, object location memory test and novel object recognition test. Ionized calcium-binding adapter molecule 1 (Iba1) staining was used to indicate the activation of microglia. Expression of M1/M2-type microglia markers and inflammatory factors were evaluated by ELISA and qRT-PCR. The G1 administration significantly reduced cerebral edema and Evans blue extravasation at injury ipsilateral cortex and basal ganglia in TBI mice. Activation of GPER1 by G1 improved the anxiety behavior and the cognitive dysfunction of mice induced by TBI. G1 administration significantly decreased Iba1-positive staining cells and the mRNA levels of CD86, macrophage cationic peptide 1 (Mcp-1), nitric oxide synthase 2 (Nos2), interleukin 1 beta (IL-1β), and macrophage inflammatory protein-2 (MIP-2), while increased the mRNA levels of interleukin 10 (IL-10), arginase1 (Arg-1) and CD206. Activation of GPER1 through G1 administration has the potential to ameliorate cognitive dysfunction induced by TBI in mice. It may also inhibit the activation of M1 microglia in cortical tissue resulting from TBI, while promoting the activation of M2 microglia and contributing to the regulation of inflammatory responses.

Factors influencing traumatic brain injuries in maxillofacial fractures: A 12-year retrospective analysis of 2841 patients

BACKGROUND/AIM

Results of studies investigating the association between traumatic brain injury (TBI) and maxillofacial fractures (MFs) have varied considerably. The present study aimed to evaluate the correlation between TBIs and MFs, as well as the impact of age, sex, trauma mechanism, and season on TBIs.

MATERIALS AND METHODS

This 12-year retrospective study of 2841 patients used univariate and multivariate logistic regression to assess the association between MFs and other factors impacting TBIs.

RESULTS

Among 2841 patients, 1978 TBIs occurred in 829 (29.2%), with intracranial injuries (n = 828) is the most common. Of 829 patients with TBIs, 688 were male and 141 were female, corresponding to a male-to-female ratio of 4.9:1.0. The most common age group was 40-49 years (24.6%). Vehicles (including motor vehicles and electric vehicles) accidents were the primary causes of injuries. Multivariate regression analyses revealed an increased risk for TBIs among males (odds ratio [OR] 0.632, p < 0.001). Patients >40 years of age were at higher risk for TBIs, especially those ≥70 years (OR 3.966, p = 0.001). Vehicle accidents were a high-risk factor for TBIs (OR 6.894, p < 0.001), and winter was the most prevalent season for such injuries (OR 1.559, p = 0.002). Risk for TBI increased by 136.4% in combined midfacial and mandibular fractures (p = 0.016) and by 101.6% in multiple midfacial fractures (p = 0.045). TBIs were less common in single mandibular fractures, notably in single-angle fractures, with a risk of only 0.204-fold.

CONCLUSION

TBIs in MFs were significantly correlated with sex, age, aetiology, season and fracture location. Maxillofacial surgeons and emergency physicians must be aware of the possible association between TBIs and MFs to assess and manage this complicated relationship in a timely manner.

Translational Medicine in Acute Ischemic Stroke and Traumatic Brain Injury-NeuroAiD Trials, from Traditional Beliefs to Evidence-Based Therapy

Acute ischemic stroke (AIS) and traumatic brain injury (TBI) are two severe neurological events, both being major causes of death and prolonged impairment. Their incidence continues to rise due to the global increase in the number of people at risk, representing a significant burden on those remaining impaired, their families, and society. These molecular and cellular mechanisms of both stroke and TBI present similarities that can be targeted by treatments with a multimodal mode of action, such as traditional Chinese medicine. Therefore, we performed a detailed review of the preclinical and clinical development of MLC901 (NeuroAiDTMII), a natural multi-herbal formulation targeting several biological pathways at the origin of the clinical deficits. The endogenous neurobiological processes of self-repair initiated by the brain in response to the onset of brain injury are often insufficient to achieve complete recovery of impaired functions. This review of MLC901 and its parent formulation MLC601 confirms that it amplifies the natural self-repair process of brain tissue after AIS or TBI. Following AIS and TBI where "time is brain", many patients enter the post-acute phase with their functions still impaired, a period when "the brain needs time to repair itself". The treatment goal must be to accelerate recovery as much as possible. MLC901/601 demonstrated a significant reduction by 18 months of recovery time compared to a placebo, indicating strong potential for facilitating the improvement of health outcomes and the more efficient use of healthcare resources.

Crocetin protects mouse brain from apoptosis in traumatic brain injury model through activation of autophagy

BACKGROUND

Autophagy is recognized as a promising therapeutic target for traumatic brain injury (TBI). Crocetin is an aglycone of crocin naturally occurring in saffron and has been found to alleviate brain injury diseases. However, whether crocetin affects autophagy after TBI remains unknown. Therefore, we explore crocetin roles in autophagy after TBI.

METHODS

We used a weight-dropped model to induce TBI in C57BL/6J mice. Neurological severity scoring (NSS) and grip tests were used to evaluate the neurological level of injury. Brain edema, neuronal apoptosis, neuroinflammation and autophagy were detected by measurements of brain water content, TUNEL staining, ELISA kits and western blotting.

RESULTS

Crocetin ameliorated neurological dysfunctions and brain edema after TBI. Crocetin reduced neuronal apoptosis and neuroinflammation and enhanced autophagy after TBI.

CONCLUSION

Crocetin alleviates TBI by inhibiting neuronal apoptosis and neuroinflammation and activating autophagy.

A Study on the Correlation of Various Factors in Patients With Severe Traumatic Brain Injuries

INTRODUCTION

Traumatic brain injury (TBI), ranging from minor impacts to severe cases, affects temporal and frontal brain areas, contributing to mortality and disability worldwide. The Glasgow Coma Scale (GCS) evaluates consciousness levels, aiding in prioritizing emergency care, while the Disability Rating Score (DRS) assesses overall function, particularly in severe cases, with greater sensitivity than GCS for clinical changes in TBI patients.

OBJECTIVES

To correlate various factors with each other in patients presented with severe TBIs.

MATERIALS AND METHODS

The retrospective study analyzed data from patients with severe TBIs admitted to the hospital from February 2023 to April 2024. Patients' demographic and clinical data, including GCS and DRS scores, were collected. Statistical analysis, including logistic regression, assessed mortality predictors.

RESULTS

The study revealed significant correlations (p<0.05) between age and marital status (p=0.002) and surgery (p=0.003). Surgery also correlated significantly with the mechanism of injury (p<0.001). Furthermore, a negative correlation was found between GCS after 24 hours and change in GCS (p<0.001), while a positive correlation existed between DRS after 24 hours and DRS on the 14th day (p<0.001). These findings highlight the complex interplay between demographic factors, medical interventions, and clinical outcomes in TBI patients.

CONCLUSION

The study found that older individuals, particularly those involved in road traffic accidents, had poorer recovery outcomes and higher rates of surgery, with a strong correlation between changes in GCS and DRS scores.

Comparing Randomized Controlled Trials of Moderate to Severe Traumatic Brain Injury in Lower to Middle Income Countries Versus High Income Countries

Outcomes from traumatic brain injury (TBI) including death differ significantly between high-, middle-, and low-income countries. Little is known, however, about differences in TBI research across the globe. The objective of this article was to examine randomized controlled trials (RCTs) of moderate-to-severe TBI in high-income countries (HICs) compared with low- and middle-income countries (LMICs), as defined by the World Bank income per capita cutoff of $13,205 US dollars. A systematic review was conducted for articles published in the English language to December 2022 inclusive using MEDLINE, PubMed, Scopus, CINAHL, EMBASE, and PsycINFO in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Inclusion criteria: (1) human participants with a mean age of ≥18 years; (2) ≥50% of the sample had moderate to severe TBI; and (3) the study design was a RCT. Data extracted included author, year, country, sample size, primary focus (medical/surgical management or rehabilitation), injury etiology, time post-injury, and indicator(s) used to define TBI severity. There were 662 RCTs (published 1978-2022) that met inclusion criteria comprising 91,946 participants. There were 48 countries represented: 30 HICs accounting for 451 RCTs (68.1%) and 18 LMICs accounting for 211 RCTs (31.9%). The 62.6% of RCTs from LMICs were conducted in the acute phase post-injury (≤1 month) compared with 42.1% of RCTs from HICs. Of RCTs from LMICs, 92.4% focused on medical/surgical management compared with 52.5% from HICs. Since 2016, more RCTs have been conducted in LMICs than in HICs, indicating the importance of better understanding this pattern of research output.

Advances in Neurorehabilitation: Strategies and Outcomes for Traumatic Brain Injury Recovery

Traumatic brain injury (TBI) consists of an external physical force that causes brain function impairment or pathology and globally affects 50 million people each year, with a cost of 400 billion US dollars. Clinical presentation of TBI can occur in many forms, and patients usually require prolonged hospital care and lifelong rehabilitation, which leads to an impact on the quality of life. For this narrative review, no particular method was used to extract data. With the aid of health descriptors and Medical Subject Heading (MeSH) terms, a search was thoroughly conducted in databases such as PubMed and Google Scholar. After the application of exclusion and inclusion criteria, a total of 146 articles were effectively used for this review. Results indicate that rehabilitation after TBI happens through neuroplasticity, which combines neural regeneration and functional reorganization. The role of technology, including artificial intelligence, virtual reality, robotics, computer interface, and neuromodulation, is to impact rehabilitation and life quality improvement significantly. Pharmacological intervention, however, did not result in any benefit when compared to standard care and still needs further research. It is possible to conclude that, given the high and diverse degree of disability associated with TBI, rehabilitation interventions should be precocious and tailored according to the individual's needs in order to achieve the best possible results. An interdisciplinary patient-centered care health team and well-oriented family members should be involved in every stage. Lastly, strategies must be adequate, well-planned, and communicated to patients and caregivers to attain higher functional outcomes.

Metabolome-Wide Mendelian Randomization Assessing the Causal Role of Serum and Cerebrospinal Metabolites in Traumatic Brain Injury

Previous studies have identified metabolites as biomarkers or potential therapeutic targets for traumatic brain injury (TBI). However, the causal association between them remains unknown. Therefore, we investigated the causal effect of serum metabolites and cerebrospinal fluid (CSF) metabolites on TBI susceptibility through Mendelian randomization (MR). Genetic variants related to metabolites and TBI were extracted from a corresponding genome-wide association study (GWAS). Causal effects were estimated through the inverse variance weighted approach, supplemented by a weighted median, weight mode, and the MR-Egger test. In addition, sensitivity analyses were further performed to evaluate the stability of the MR results, including the MR-Egger intercept, leave-one-out analysis, Cochrane's Q-test, and the MR-PRESSO global test. Metabolic pathway analysis was applied to uncover the underlying pathways of the significant metabolites in TBI. In blood metabolites, substances such as 4-acetaminophen sulfate and kynurenine showed positive links, whereas beta-hydroxyisovalerate and creatinine exhibited negative correlations. CSF metabolites such as N-formylanthranilic acid were positively related, while kynurenate showed negative associations. The metabolic pathway analysis highlighted the potential biological pathways involved in TBI. Of these 16 serum metabolites, 11 CSF metabolites and metabolic pathways may serve as useful circulating biomarkers in clinical screening and prevention, and may be candidate molecules for the exploration of mechanisms and drug targets.

A Modern Approach to the Treatment of Traumatic Brain Injury

Background: Traumatic brain injury manifests itself in various forms, ranging from mild impairment of consciousness to severe coma and death. Traumatic brain injury remains one of the leading causes of morbidity and mortality. Currently, there is no therapy to reverse the effects associated with traumatic brain injury. New neuroprotective treatments for severe traumatic brain injury have not achieved significant clinical success. Methods: A literature review was performed to summarize the recent interdisciplinary findings on management of traumatic brain injury from both clinical and experimental perspective. Results: In the present review, we discuss the concepts of traditional and new approaches to treatment of traumatic brain injury. The recent development of different drug delivery approaches to the central nervous system is also discussed. Conclusions: The management of traumatic brain injury could be aimed either at the pathological mechanisms initiating the secondary brain injury or alleviating the symptoms accompanying the injury. In many cases, however, the treatment should be complex and include a variety of medical interventions and combination therapy.

Association of Cadherin-Related Family Member 1 with Traumatic Brain Injury

The cadherin family plays a pivotal role in orchestrating synapse formation in the central nervous system. Cadherin-related family member 1 (CDHR1) is a photoreceptor-specific calmodulin belonging to the expansive cadherin superfamily. However, its role in traumatic brain injury (TBI) remains largely unknown. CDHR1 expression across various brain tissue sites was analyzed using the GSE104687 dataset. Employing a summary-data-based Mendelian Randomization (SMR) approach, integrated analyses were performed by amalgamating genome-wide association study abstracts from TBI with public data on expressed quantitative trait loci and DNA methylation QTL from both blood and diverse brain tissues. CDHR1 expression and localization in different brain tissues were meticulously delineated using western blotting, immunohistochemistry, and enzyme-linked immunosorbent assay. CDHR1 expression was consistently elevated in the TBI group compared to that in the sham group across multiple tissues. The inflammatory response emerged as a crucial biological mechanism, and pro-inflammatory and anti-inflammatory factors were not expressed in either group. Integrated SMR analyses encompassing both blood and brain tissues substantiated the heightened CDHR1 expression profiles, with methylation modifications emerging as potential contributing factors for increased TBI risk. This was corroborated by western blotting and immunohistochemistry, confirming augmented CDHR1 expression following TBI. This multi-omics-based genetic association study highlights the elevated TBI risk associated with CDHR1 expression coupled with putative methylation modifications. These findings provide compelling evidence for future targeted investigations and offer promising avenues for developing interventional therapies for TBI.

Prehospital Trauma Care

Prehospital trauma evaluation begins with the primary assessment of airway, breathing, circulation, disability, and exposure. This is closely followed by vital signs and a secondary assessment. Key prehospital interventions include management and resuscitation according to the aforementioned principles with a focus on major hemorrhage control, airway compromise, and invasive management of tension pneumothorax. Determining the appropriate time and method for transportation (eg, ground ambulance, helicopter, police, private vehicle) to the hospital or when to terminate resuscitation are also important decisions to be made by emergency medical services clinicians.

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.

Human factor engineering of point-of-care near infrared spectroscopy device for intracranial hemorrhage detection in Traumatic Brain Injury: A multi-center comparative study using a hybrid methodology

OBJECTIVE

This study assessed machine learning powered Near-infrared spectroscopy based (mNIRS) device's usability and human factor ergonomics in four distinct healthcare provider groups.

BACKGROUND

Traumatic Brain Injury (TBI) is a global concern with significant well-being implications. Timely intracranial hemorrhage (ICH) detection is crucial. mNIRS offers efficient non-invasive TBI screening.

METHODS

Two device utilization stages involved operators (N = 21) and TBI-suspected subjects (n = 120). A hybrid approach used qualitative and quantitative methods, utilizing a 57-item survey and task completion time.

RESULTS

All groups positively perceived user-interface, physical, cognitive, and organizational ergonomics. The device's ease of use, calibration, size, cognitive support, and integration gained appreciation. Training reduced task completion time from 16.5 to 13.2 s.

CONCLUSION

mNIRS-based CEREBO® proves usable for TBI point-of-care assessment. Positive feedback from diverse healthcare groups validates design and cost-effectiveness alignment. A hybrid approach, training, and practice scans enhance usage and experience.

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.

Assessing the impact of pre-hospital airway management on severe traumatic Brain injury: A systematic review and Meta-analysis

OBJECTIVE

This study aimed to assess the impact of establishing a pre-hospital definitive airway on mortality and morbidity compared with no prehospital airway in cases of severe traumatic brain injury (TBI).

BACKGROUND

Traumatic brain injury (TBI) is a global health concern that is associated with substantial morbidity and mortality. Prehospital intubation (PHI) has been proposed as a potential life-saving intervention for patients with severe TBI to mitigate secondary insults, such as hypoxemia and hypercapnia. However, their impact on patient outcomes remains controversial.

METHODS

A systematic review and meta-analysis were conducted to assess the effects of prehospital intubation versus no prehospital intubation on morbidity and mortality in patients with severe TBI, adhering to the PRISMA guidelines.

RESULTS

24 studies, comprising 56,543 patients, indicated no significant difference in mortality between pre-hospital and In-hospital Intubation (OR 0.89, 95% CI 0.65-1.23, p = 0.48), although substantial heterogeneity was noted. Morbidity analysis also showed no significant difference (OR 0.83, 95% CI 0.43-1.63, p = 0.59). These findings underscore the need for cautious interpretation due to heterogeneity and the influence of specific studies on the results.

CONCLUSION

In summary, an initial assessment did not reveal any apparent disparity in mortality rates between individuals who received prehospital intubation and those who did not. However, subsequent analyses and randomized controlled trials (RCTs) demonstrated that patients who underwent prehospital intubation had a reduced risk of death and morbidity. The dependence on biased observational studies and the need for further replicated RCTs to validate these findings are evident. Despite the intricacy of the matter, it is crucial to intervene during severe airway impairment.

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.

Hypoxically stored RBC resuscitation in a rat model of traumatic brain injury and severe hemorrhagic shock

This study aims to investigate the effects of hypoxically stored Red Blood Cells (RBCs) in a rat model of traumatic brain injury followed by severe hemorrhagic shock (HS) and resuscitation. RBCs were made hypoxic using an O2 depletion system (Hemanext Inc. Lexington, MA) and stored for 3 weeks. Experimental animals underwent craniotomy and blunt brain injury followed by severe HS. Rats were resuscitated with either fresh RBCs (FRBCs), 3-week-old hypoxically stored RBCs (HRBCs), or 3-week-old conventionally stored RBCs (CRBCs). Resuscitation was provided via RBCs transfusion equivalent to 70 % of the shed blood and animals were followed for 2 h. The control group was comprised of healthy animals that were not instrumented or injured. Post-resuscitation hemodynamics and lactate levels were improved with FRBCs and HRBCs, and markers of organ injury in the liver (Aspartate aminotransferase [AST]), lung (chemokine ligand 1 [CXCL-1] and Leukocytes count), and heart (cardiac troponin, Interleukin- 6 [IL-6] and Tumor Necrosis Factor Alpha[TNF-α]) were lower with FRBCs and HRBCs resuscitation compared to CRBCs. Following reperfusion, biomarkers for oxidative stress, lipid peroxidation, and RNA/DNA injury were assessed. Superoxide dismutase [SOD] levels in the HRBCs group were similar to the FRBCs group and levels in both groups were significantly higher than CRBCs. Catalase levels were not different than control values in the FRBCs and HRBCs groups but significantly lower with CRBCs. Thiobarbituric acid reactive substances [Tbars] levels were higher for both CRBCs and HRBCs. Hypoxically stored RBCs show few differences from fresh RBCs in resuscitation from TBI + HS and decreased organ injury and oxidative stress compared to conventionally stored RBCs.

Novel perfluorocarbon-based oxygenation therapy alleviates Post-SAH hypoxic brain injury by inhibiting HIF-1α

In comparison to other stroke types, subarachnoid hemorrhage (SAH) is characterized by an early age of onset and often results in poor prognosis. The inadequate blood flow at the site of the lesion leads to localized oxygen deprivation, increased level of hypoxia-inducible factor-1α (HIF-1α), and triggers inflammatory responses and oxidative stress, ultimately causing hypoxic brain damage. Despite the potential benefits of oxygen (O2) administration, there is currently a lack of efficient focal site O2 delivery following SAH. Conventional clinical O2 supply methods, such as transnasal oxygenation and hyperbaric oxygen therapy, do not show the ideal therapeutic effect in severe SAH patients. The perfluorocarbon oxygen carrier (PFOC) demonstrates efficacy in transporting O2 and responding to elevated levels of CO2 at the lesion site. Through cellular experiments, we determined that PFOC oxygenation serves as an effective therapeutic approach in inhibiting hypoxia. Furthermore, our animal experiments showed that PFOC oxygenation outperforms O2 breathing, leading to microglia phenotypic switching and the suppression of inflammatory response via the inhibition of HIF-1α. Therefore, as a new type of O2 therapy after SAH, PFOC oxygenation can effectively reduce hypoxic brain injury and improve neurological function.

Nomogram for Predicting Central Nervous System Infection Following Traumatic Brain Injury in the Elderly

OBJECTIVE

This study aims to identify risk factors for central nervous system (CNS) infection in elderly patients hospitalized with traumatic brain injury (TBI) and to develop a reliable predictive tool for assessing the likelihood of CNS infection in this population.

METHOD

We conducted a retrospective study on 742 elderly TBI patients treated at Tangdu Hospital, China. Clinical data was randomly split into training and validation sets (7:3 ratio). By conducting univariate and multivariate logistic regression analysis in the training set, we identified a list of variables to develop a nomogram for predicting the risk of CNS infection. We evaluated the performance of the predictive model in both cohorts respectively, using receiver operating characteristics curves, calibration curves, and decision curve analysis.

RESULTS

Results of the logistic analysis in the training set indicated that surgical intervention (P = 0.007), red blood cell count (P = 0.019), C-reactive protein concentration (P < 0.001), and cerebrospinal fluid leakage (P < 0.001) significantly predicted the occurrence of CNS infection in elderly TBI patients. The model constructed based on these variables had high predictive capability (area under the curve-training = 0.832; area under the curve-validation = 0.824) as well as clinical utility.

CONCLUSIONS

A nomogram constructed based on several key predictors reasonably predicts the risk of CNS infection in elderly TBI patients upon hospital admission. The model of the nanogram may contribute to timely interventions and improve health outcomes among affected individuals.

Role of Gabapentin in Traumatic Brain Injury: A Prospective Comparative Study

Background

Traumatic brain injury (TBI) is a major cause of mortality among young individuals, accounting for 65% of deaths in road traffic accidents. Paroxysmal sympathetic hyperactivity (PSH) is a common syndrome associated with TBI. This study represents the first prospective investigation aimed at assessing the impact of gabapentin on TBI patients, focusing on the prevention of secondary brain injury and brain edema while enhancing the Glasgow Coma Scale (GCS).

Materials and methods

The study was conducted from September 2019 to July 2021 after receiving ethical committee approval. It included adult ICU patients (≥18 years) with moderate and severe GCS. Patients below 18 years, death within 48 hours, non-consenting, pregnant females, and individuals allergic to gabapentin were excluded from the study. Patients were randomly allocated in two groups: study group received 300 mg of gabapentin orally twice daily and control group received multivitamin tablets twice daily. The treatment period spanned 2 weeks. Follow-up occurred in the ICU and continued for up to 3 months post-discharge, including telephonic conversations.

Results

About 60 patients were involved for analysis. Significant differences were found in GCS change from admission to discharge, Glasgow Outcome Scale (GOS) at 30 and 90 days, PSH episodes, and sedation bolus per day. Glasgow Coma Scale change was 53% in the study group compared with 25% in the control group (p = 0.009). Mortality was significantly lower in the study group. Glasgow Outcome Scale change between 30 and 90 days showed a 25% improvement in cases and no change in controls (p = 0.001).

Conclusion

This pioneering study underscores the potential of gabapentin in managing traumatic brain injuries.

How to cite this article

Singh R, Ambasta S, Bais PS, Azim A, Kumar S, Upreti B, et al. Role of Gabapentin in Traumatic Brain Injury: A Prospective Comparative Study. Indian J Crit Care Med 2024;28(2):120-125.

Optic Nerve Sheath Diameter Sonography for the Diagnosis of Intracranial Hypertension in Traumatic Brain Injury: A Systematic Review and Meta-Analysis

OBJECTIVES

Timely diagnosis and management of elevated intracranial pressure (ICP) in patients with traumatic brain injury (TBI) can significantly reduce mortality rates. Ultrasound examination of the optic nerve sheath diameter (ONSD) is considered a potential, noninvasive, and effective method for assessing ICP. We conducted a systematic review and meta-analysis of ONSD ultrasound detection and invasive ICP monitoring methods to compare and evaluate the diagnostic accuracy of ONSD ultrasound detection methods for intracranial hypertension (IH) in patients with TBI.

METHODS

We searched the Web of Science, PubMed, and Embase databases to assess the diagnostic accuracy of ONSD sonography for predicting increased ICP. The 2 authors independently extracted the collected data. Simultaneously, the QUADAS-2 tool was used to evaluate the bias risk of each study and conducted random-effects meta-analyses for the accuracy and specificity of diagnosis, and calculated pooled estimates.

RESULTS

Ten studies with 512 patients were included. The diagnostic accuracy of ONSD sonography for IH was revealed as a pooled sensitivity of 0.85 (95% confidence interval [CI], 0.79-0.89) and specificity of 0.88 (95% CI, 0.80-0.93), compared with the invasive ICP monitoring standard for patients with TBI.

CONCLUSIONS

ONSD sonography may be a useful method for predicting increased ICP in adult patients with TBI. Further clinical studies are required to confirm the diagnostic value of ONSD sonography.

Clinical characteristics and outcomes of traumatic brain injury in patients admitted to surgical ward of Jimma Medical Center, Southwest Ethiopia: a prospective observational follow-up study

OBJECTIVE

To assess the Clinical Characteristics and Outcomes of Traumatic Brain Injury in Patients Admitted to the Surgical Ward of Jimma Medical Center, Southwest Ethiopia from January to July 2022.

DESIGN AND SETTING

A hospital-based prospective observational study was conducted among 175 patients admitted with Traumatic Brain Injury at Jimma Medical Center from January to July 2022. Data were collected by structured questionnaires and a convenient sampling technique was used. For data entry, Epidata V.4.6.0.5 software was used and exported to Stata V.14.0.2 for analysis. The Cox regression model was fitted to evaluate the predictors of mortality and variables with a p value <0.05 at 95% CI were taken as statistically significant predictors.

RESULTS

The incidence of in-hospital mortality was 22 (12.6%). The mean length of hospital stay was 6 days. In-hospital complications were recorded in 32.0% of patients. A Glasgow Coma Scale (GCS) score of <8 on admission (adjusted HR (AHR)=6.2, 95% CI 0.75 to 51), hyperthermia (AHR: 1.7, 95% CI 1.02 to 3.05) and lack of prehospital care (AHR: 3.2, 95% CI 2.2 to 8.07) were predictors of mortality in patients with traumatic brain injury.

CONCLUSION

In-hospital mortality was recorded in over one-tenth of patients with traumatic brain injury. The GCS score of <8 on admission, hyperthermia and lack of prehospital care positively affected the outcome of patients with traumatic brain injury. Screening of patients for hyperthermia and antipsychotics should be strengthened to reduce death. However, a multicentred study is needed for further evidence. Giving priority to the patients with those predictors will decrease the number of deaths.

Functional connectivity, tissue microstructure and T2 at 11.1 Tesla distinguishes neuroadaptive differences in two traumatic brain injury models in rats: A Translational Outcomes Project in NeuroTrauma (TOP-NT) UG3 phase study

The damage caused by contusive traumatic brain injuries (TBIs) is thought to involve breakdown in neuronal communication through focal and diffuse axonal injury along with alterations to the neuronal chemical environment, which adversely affects neuronal networks beyond the injury epicenter(s). In the present study, functional connectivity along with brain tissue microstructure coupled with T2 relaxometry were assessed in two experimental TBI models in rat, controlled cortical impact (CCI) and lateral fluid percussive injury (LFPI). Rats were scanned on an 11.1 Tesla scanner on days 2 and 30 following either CCI or LFPI. Naive controls were scanned once and used as a baseline comparison for both TBI groups. Scanning included functional magnetic resonance imaging (fMRI), diffusion weighted images (DWI), and multi-echo T2 images. fMRI scans were analyzed for functional connectivity across laterally and medially located region of interests (ROIs) across the cortical mantle, hippocampus, and dorsal striatum. DWI scans were processed to generate maps of fractional anisotropy, mean, axial, and radial diffusivities (FA, MD, AD, RD). The analyses focused on cortical and white matter (WM) regions at or near the TBI epicenter. Our results indicate that rats exposed to CCI and LFPI had significantly increased contralateral intra-cortical connectivity at 2 days post-injury. This was observed across similar areas of the cortex in both groups. The increased contralateral connectivity was still observed by day 30 in CCI, but not LFPI rats. Although both CCI and LFPI had changes in WM and cortical FA and diffusivities, WM changes were most predominant in CCI and cortical changes in LFPI. Our results provide support for the use of multimodal MR imaging for different types of contusive and skull-penetrating injury.

Targeting pyroptosis with nanoparticles to alleviate neuroinflammatory for preventing secondary damage following traumatic brain injury

Posttraumatic neuroinflammation is a key driver of secondary injury after traumatic brain injury (TBI). Pyroptosis, a proinflammatory form of programmed cell death, considerably activates strong neuroinflammation and amplifies the inflammatory response by releasing inflammatory contents. Therefore, treatments targeting pyroptosis may have beneficial effects on the treatment of secondary brain damage after TBI. Here, a cysteine-alanine-glutamine-lysine peptide-modified β-lactoglobulin (β-LG) nanoparticle was constructed to deliver disulfiram (DSF), C-β-LG/DSF, to inhibit pyroptosis and decrease neuroinflammation, thereby preventing TBI-induced secondary injury. In the post-TBI mice model, C-β-LG/DSF selectively targets the injured brain, increases DSF accumulation, and extends the time of the systemic circulation of DSF. C-β-LG/DSF can alleviate brain edema and inflammatory response, inhibit secondary brain injury, promote learning, and improve memory recovery in mice after trauma. Therefore, this study likely provided a potential approach for reducing the secondary spread of TBI.

Emerging Neuroprotective Strategies: Unraveling the Potential of HDAC Inhibitors in Traumatic Brain Injury Management

Traumatic brain injury (TBI) is a significant global health problem, leading to high rates of mortality and disability. It occurs when an external force damages the brain, causing immediate harm and triggering further pathological processes that exacerbate the condition. Despite its widespread impact, the underlying mechanisms of TBI remain poorly understood, and there are no specific pharmacological treatments available. This creates an urgent need for new, effective neuroprotective drugs and strategies tailored to the diverse needs of TBI patients. In the realm of gene expression regulation, chromatin acetylation plays a pivotal role. This process is controlled by two classes of enzymes: histone acetyltransferase (HAT) and histone deacetylase (HDAC). These enzymes modify lysine residues on histone proteins, thereby determining the acetylation status of chromatin. HDACs, in particular, are involved in the epigenetic regulation of gene expression in TBI. Recent research has highlighted the potential of HDAC inhibitors (HDACIs) as promising neuroprotective agents. These compounds have shown encouraging results in animal models of various neurodegenerative diseases. HDACIs offer multiple avenues for TBI management: they mitigate the neuroinflammatory response, alleviate oxidative stress, inhibit neuronal apoptosis, and promote neurogenesis and axonal regeneration. Additionally, they reduce glial activation, which is associated with TBI-induced neuroinflammation. This review aims to provide a comprehensive overview of the roles and mechanisms of HDACs in TBI and to evaluate the therapeutic potential of HDACIs. By summarizing current knowledge and emphasizing the neuroregenerative capabilities of HDACIs, this review seeks to advance TBI management and contribute to the development of targeted treatments.

Outlier Analysis for Acute Blood Biomarkers of Moderate and Severe Traumatic Brain Injury

Blood biomarkers have been studied to improve the clinical assessment and prognostication of patients with moderate-severe traumatic brain injury (mo/sTBI). To assess their clinical usability, one needs to know of potential factors that might cause outlier values and affect clinical decision making. In a prospective study, we recruited patients with mo/sTBI (n = 85) and measured the blood levels of eight protein brain pathophysiology biomarkers, including glial fibrillary acidic protein (GFAP), S100 calcium-binding protein B (S100B), neurofilament light (Nf-L), heart-type fatty acid-binding protein (H-FABP), interleukin-10 (IL-10), total tau (T-tau), amyloid β40 (Aβ40) and amyloid β42 (Aβ42), within 24 h of admission. Similar analyses were conducted for controls (n = 40) with an acute orthopedic injury without any head trauma. The patients with TBI were divided into subgroups of normal versus abnormal (n = 9/76) head computed tomography (CT) and favorable (Glasgow Outcome Scale Extended [GOSE] 5-8) versus unfavorable (GOSE <5) (n = 38/42, 5 missing) outcome. Outliers were sought individually from all subgroups from and the whole TBI patient population. Biomarker levels outside Q1 - 1.5 interquartile range (IQR) or Q3 + 1.5 IQR were considered as outliers. The medical records of each outlier patient were reviewed in a team meeting to determine possible reasons for outlier values. A total of 29 patients (34%) combined from all subgroups and 12 patients (30%) among the controls showed outlier values for one or more of the eight biomarkers. Nine patients with TBI and five control patients had outlier values in more than one biomarker (up to 4). All outlier values were > Q3 + 1.5 IQR. A logical explanation was found for almost all cases, except the amyloid proteins. Explanations for outlier values included extremely severe injury, especially for GFAP and S100B. In the case of H-FABP and IL-10, the explanation was extracranial injuries (thoracic injuries for H-FABP and multi-trauma for IL-10), in some cases these also were associated with abnormally high S100B. Timing of sampling and demographic factors such as age and pre-existing neurological conditions (especially for T-tau), explained some of the abnormally high values especially for Nf-L. Similar explanations also emerged in controls, where the outlier values were caused especially by pre-existing neurological diseases. To utilize blood-based biomarkers in clinical assessment of mo/sTBI, very severe or fatal TBIs, various extracranial injuries, timing of sampling, and demographic factors such as age and pre-existing systemic or neurological conditions must be taken into consideration. Very high levels seem to be often associated with poor prognosis and mortality (GFAP and S100B).

Post-traumatic hydrocephalus: An overview of classification, diagnosis, treatment, and post-treatment imaging evaluation

The syndrome of post-traumatic hydrocephalus (PTH) has been recognized since Dandy's report in 1914. The pathogenesis of PTH has not been fully clarified. At present, it is believed that the obstacles of cerebrospinal fluid (CSF) secretion, absorption and circulation pathways are the reasons for the development of PTH. However, recent studies have also suggested that the osmotic pressure load of CSF and the pathological changes of CSF dynamics are caused by the development of hydrocephalus. Therefore, a better understanding of the definition, classification, diagnostic criteria, treatment, and evaluation of post-treatment effects of PTH is critical for the effective prevention and treatment of PTH. In this paper, we reviewed the classification and diagnosis of PTH and focused on the treatment and the imaging evaluation of post-treatment effects of PTH. This review might provide a judgment criterion for diagnosis of PTH and a basis for the effective prevention and treatment of PTH in the future.

Patients with both traumatic brain injury and hemorrhagic shock benefit from resuscitation with whole blood

BACKGROUND

Hemorrhagic shock in the setting of traumatic brain injury (TBI) reduces cerebral blood flow and doubles mortality. The optimal resuscitation strategy for hemorrhage in the setting of TBI is unknown. We hypothesized that, among patients presenting with concomitant hemorrhagic shock and TBI, resuscitation including whole blood (WB) is associated with decreased overall and TBI-related mortality when compared with patients receiving component (COMP) therapy alone.

METHODS

An a priori subgroup of prospective, observational cohort study of injured patients receiving emergency-release blood products for hemorrhagic shock is reported. Adult trauma patients presenting November 2017 to September 2020 with TBI, defined as a Head Abbreviated Injury Scale of ≥3, were included. Whole blood group patients received any cold-store low-titer Group O WB units. The COMP group received fractionated blood components alone. Overall and TBI-related 30-day mortality, favorable discharge disposition (home or rehabilitation), and 24-hour blood product utilization were assessed. Univariate and inverse probabilities of treatment-weighted multivariable analyses were performed.

RESULTS

Of 564 eligible patients, 341 received WB. Patients who received WB had a higher injury severity score (median, 34 vs. 29), lower scene blood pressure (104 vs. 118), and higher arrival lactate (4.3 vs. 3.6, all p < 0.05). Univariate analysis noted similar overall mortality between WB and COMP; however, weighted multivariable analyses found WB was associated with decreased overall mortality and TBI-related mortality. There were no differences in discharge disposition between the WB group and COMP group.

CONCLUSION

In patients with concomitant hemorrhagic shock and TBI, WB transfusion was associated with decreased overall mortality and TBI-related mortality. Whole blood should be considered a first-line therapy for hemorrhage in the setting of TBI.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

Anacardic acid improves neurological deficits in traumatic brain injury by anti-ferroptosis and anti-inflammation

BACKGROUND

Traumatic brain injury (TBI) is an important cause of disability and death. TBI leads to multiple forms of nerve cell death including ferroptosis due to iron-dependent lipid peroxidation. Anacardic acid (AA) is a natural component extracted from cashew nut shells, which has been reported to have neuroprotective effects in traumatic brain injury. We investigated whether AA has an anti-ferroptosis effect in TBI.

METHODS

We used the Feeney free-fall impact method to construct a TBI model to investigate the effect of AA on ferroptosis caused by TBI, in which Ferrostatin-1 (Fer-1), a ferroptosis inhibitor, served as a positive control group. We first identified the therapeutic effect of AA on TBI through modified neurological severity score (mNSS) and determined the appropriate concentration. Secondly, we investigated the effect of AA on the expression level of the key protein of ferroptosis by Western blotting and immunohistochemistry. Then the effect of AA on nerve tissue injury and nerve function improvement was verified. Finally, enzym-linked immunosorbent assay (ELISA) was used to verify that AA could reduce inflammation after TBI.

RESULTS

We found the intensely inhibitory effect of AA on ferroptosis, which is in parallel with the results obtained after Fer-1 treatment. In addition, AA and Fer-1 mitigated TBI-mediated tissue defects, destruction of the blood-brain barrier, and neurodegeneration. Novel object recognition (NOR), mNSS and water maze test showed that AA could significantly reduce the impairment of neural function and behavioral cognitive ability caused by TBI. Finally, we also demonstrated that AA has not only an anti-ferroptosis effect, but also an anti-inflammation effect.

CONCLUSIONS

AA can reduce the neurological impairment and behavioral cognitive impairment caused by TBI through the dual effect of anti-ferroptosis and anti-inflammation.

Diagnostic Accuracy and Performance Analysis of a Scanner-Integrated Artificial Intelligence Model for the Detection of Intracranial Hemorrhages in a Traumatology Emergency Department

Intracranial hemorrhages require an immediate diagnosis to optimize patient management and outcomes, and CT is the modality of choice in the emergency setting. We aimed to evaluate the performance of the first scanner-integrated artificial intelligence algorithm to detect brain hemorrhages in a routine clinical setting. This retrospective study includes 435 consecutive non-contrast head CT scans. Automatic brain hemorrhage detection was calculated as a separate reconstruction job in all cases. The radiological report (RR) was always conducted by a radiology resident and finalized by a senior radiologist. Additionally, a team of two radiologists reviewed the datasets retrospectively, taking additional information like the clinical record, course, and final diagnosis into account. This consensus reading served as a reference. Statistics were carried out for diagnostic accuracy. Brain hemorrhage detection was executed successfully in 432/435 (99%) of patient cases. The AI algorithm and reference standard were consistent in 392 (90.7%) cases. One false-negative case was identified within the 52 positive cases. However, 39 positive detections turned out to be false positives. The diagnostic performance was calculated as a sensitivity of 98.1%, specificity of 89.7%, positive predictive value of 56.7%, and negative predictive value (NPV) of 99.7%. The execution of scanner-integrated AI detection of brain hemorrhages is feasible and robust. The diagnostic accuracy has a high specificity and a very high negative predictive value and sensitivity. However, many false-positive findings resulted in a relatively moderate positive predictive value.

Use of Levetiracetam for Post-Traumatic Seizure Prophylaxis in Combat-Related Traumatic Brain Injury

INTRODUCTION

Post-traumatic seizure (PTS) prophylaxis is recommended in patients with traumatic brain injury (TBI) at high risk for PTSs, but consensus on the optimal pharmacologic therapy has not yet been established. Levetiracetam is frequently used for seizure prophylaxis in combat-related TBI, but its efficacy and safety in this patient population has not yet been described.

METHODS

A retrospective cohort of 687 consecutive casualties transferred to the CONUS from October 2010 to December 2015 was analyzed. Seventy-one patients with combat-related injuries and radiographic evidence of skull fractures or intracranial hemorrhage were included. Data collection included demographics and injury characteristics including initial Glasgow Coma Scale, computed tomography findings, interventions, and 6-month Glasgow Outcome Score.

RESULTS

All patients in this cohort were male, with an average age of 25 (median 24; Interquartile range (IQR) 4.5) and an average Injury Severity Score of 28 (median 27; IQR 15). The most common mechanism of injury was explosive blast (76%). Penetrating TBI was common (51%). Most patients (88.7%) were administered seizure prophylaxis. Of these, the majority (61/63) received levetiracetam, and the additional two were administered phenytoin. The remaining 11.3% of patients were deemed not to require seizure prophylaxis. The incidence of seizures while on prophylaxis was low (2.8%) and occurred in patients who suffered transcranial gunshot wounds and ultimately died. No serious adverse effects were attributed to levetiracetam.

CONCLUSIONS

Levetiracetam appears to be a safe and effective medication for PTS prophylaxis in combat casualties. The rate of PTSs in combat-related TBI on appropriate prophylaxis is low.

PEG hydrogel containing dexamethasone-conjugated hyaluronic acid reduces secondary injury and improves motor function in a rat moderate TBI model

Traumatic brain injury (TBI) leads to long-term impairments in motor and cognitive function. TBI initiates a secondary injury cascade including a neuro-inflammatory response that is detrimental to tissue repair and limits recovery. Anti-inflammatory corticosteroids such as dexamethasone can reduce the deleterious effects of secondary injury; but challenges associated with dosing, administration route, and side effects have hindered their clinical application. Previously, we developed a hydrolytically degradable hydrogel (PEG-bis-AA/HA-DXM) composed of poly (ethylene) glycol-bis-(acryloyloxy acetate) (PEG-bis-AA) and dexamethasone-conjugated hyaluronic acid (HA-DXM) for local and sustained dexamethasone delivery. In this study, we evaluated the effect of locally applied PEG-bis-AA/HA-DXM hydrogel on secondary injury and motor function recovery after moderate controlled cortical impact (CCI) TBI. Hydrogel treatment significantly improved motor function evaluated by beam walk and rotarod tests compared to untreated rats over 7 days post-injury (DPI). We also observed that the hydrogel treatment reduced lesion volume, inflammatory response, astrogliosis, apoptosis, and increased neuronal survival compared to untreated rats at 7 DPI. These results suggest that PEG-bis-AA/HA-DXM hydrogels can mitigate secondary injury and promote motor functional recovery following moderate TBI.

Effect of Hyperbaric Oxygen Intervention on Oxidative Stress and Expression of Nerve Growth Factor in Patients with Craniocerebral Injury

Objective

To examine the impact of hyperbaric oxygen intervention on oxidative stress and nerve growth factor in patients with craniocerebral injury.

Methods

Using the random number table method, 40 patients with craniocerebral injury who were treated at the First People's Hospital of Nantong were randomly assigned to either the control group or the hyperbaric oxygen group, with 20 patients in each group. The control group received routine intervention for clinical traumatic brain injury, while the hyperbaric oxygen group received additional hyperbaric oxygen intervention during the 7 to 30 days of routine intervention. Indicators of oxidative stress and nerve growth factor levels were compared between the two groups at the time of admission and 30 days after therapy.

Results

The serum levels of superoxide dismutase, endothelium-derived relaxing factor-nitric oxide, and nerve growth factor in the hyperbaric oxygen group increased more significantly than in the control group. The serum malondialdehyde concentration was also significantly reduced in the hyperbaric oxygen group.

Conclusion

Hyperbaric oxygen intervention can successfully lower systemic oxidative stress response and increase the expression level of nerve growth factor in patients with craniocerebral injury.

Novel hemicraniectomy: Preserving temporal structures in severe traumatic brain injury patients

OBJECTIVE

This study evaluates the efficacy and safety of Novel Hemicraniectomy Technique (NHT) in Severe Traumatic Brain Injury (STBI) patients.

METHODS

A retrospective analysis of 79 STBI patients who underwent decompressive hemicraniectomy was conducted. The study compared 25 patients treated with NHT and 54 patients treated with Classic Decompressive Craniectomy (CDC), focusing on therapeutic effects, complications, intracranial pressure, and prognosis.

RESULTS

NHT resulted in shorter surgery duration (101.4 ± 11.8 min, p = 0.008) and greater decompressive effects (21.4 ± 5.6 mmHg, p = 0.018). It also prevented temporal muscle injury (0.0 %, p = 0.026), superficial temporal artery injury (0.0 %, p = 0.009), and masticatory dysfunction (5.9 %, p = 0.040). However, NHT showed no significant advantages in intracranial pressure normalization time (3.5 ± 0.9 days, p = 0.679), hospital stay length (34.3 ± 10.4 days, p = 0.805), intraoperative blood loss reduction (284.0 ± 82.6 ml, p = 0.190), or Glasgow Outcome Scale (GOS) scores (2.8 ± 0.9, p = 0.814) and prognosis (32.0 %, p = 0.831) compared to CDC.

CONCLUSION

NHT offers shorter surgery duration (101.4 ± 11.8 min vs 107.7 ± 8.2 min), superior decompressive effects (21.4 ± 5.6 mmHg vs 17.7 ± 6.9 mmHg), and better protection of temporal structures, but does not significantly reduce complications or improve prognosis compared to CDC. Prospective studies with larger sample sizes are needed to better understand the potential benefits of NHT in STBI treatment.

Fibrinogen; a predictor of injury severity and mortality among patients with traumatic brain injury in Sub-Saharan Africa: A cross-sectional observational study

Studies show that fibrinogen concentrations <2 g/L in patients with traumatic brain injury (TBI) is associated with increased mortality. However, little is known regarding fibrinogen levels and TBI severity as well as mortality in sub-Saharan Africa despite shouldering a high burden of TBI. We therefore set out to determine whether fibrinogen levels are associated with TBI severity and outcome. To determine the sensitivity and specificity of fibrinogen levels and the association with severity and mortality among TBI patients at Mulago Hospital. We prospectively enrolled 213 patients with TBI aged between 13 and 60 years of age and presenting within 24 hours of injury. Patients with preexisting coagulopathy, concurrent use of anticoagulant or antiplatelet agents, preexisting hepatic insufficiency, diabetes mellitus and who were pregnant were excluded. Fibrinogen levels were determined using the Clauss fibrinogen assay. Logistic regression analyses were conducted to identify the association between fibrinogen level and 7-day outcomes. Majority of the patients were male (88.7%) and nearly half were aged 30 or less (48.8%). Fibrinogen levels <2 g/L were observed in 35.1% of the study participants. The average time spent in the study was 3.7 ± 2.4 days. The sensitivity and specificity using fibrinogen <2 g/L was 56.5% and 72.9% respectively. Fibrinogen levels predict TBI severity with an AUC = 0.656 (95% CI 0.58-0.73: P = .000) Fibrinogen levels <2 g/L (hypofibrinogenemia) were independently associated with severe TBI. (Adjusted odds ratio 2.87 CI, 1.34-6.14: P = .007). Levels above 4.5 g/L were also independently associated with injury severity (adjusted odds ratio 2.89, CI 1.12-7.48: P < .05) Fibrinogen levels more than 4.5 g/L were independently associated with mortality (OR 4.5, CI; 1.47-13.61, P < .05). The fibrinogen level is a useful tool in predicting severity including mortality of TBI. Fibrinogen levels may be used as an additional tool to screen TBI patients for injury severity especially among patients with Glasgow coma scale scores of <14.

Head Kinematics, Blood Biomarkers, and Histology in Large Animal Models of Traumatic Brain Injury and Hemorrhagic Shock

Traumatic brain injury (TBI) and severe blood loss resulting in hemorrhagic shock (HS) are each leading causes of mortality and morbidity worldwide, and present additional treatment considerations when they are comorbid (TBI+HS) as a result of competing pathophysiological responses. The current study rigorously quantified injury biomechanics with high precision sensors and examined whether blood-based surrogate markers were altered in general trauma as well as post-neurotrauma. Eighty-nine sexually mature male and female Yucatan swine were subjected to a closed-head TBI+HS (40% of circulating blood volume; n = 68), HS only (n = 9), or sham trauma (n = 12). Markers of systemic (e.g., glucose, lactate) and neural functioning were obtained at baseline, and at 35 and 295 min post-trauma. Opposite and approximately twofold differences existed for both magnitude (device > head) and duration (head > device) of quantified injury biomechanics. Circulating levels of neurofilament light chain (NfL), glial fibrillary acidic protein (GFAP), and ubiquitin C-terminal hydrolase L1 (UCH-L1) demonstrated differential sensitivity for both general trauma (HS) and neurotrauma (TBI+HS) relative to shams in a temporally dynamic fashion. GFAP and NfL were both strongly associated with changes in systemic markers during general trauma and exhibited consistent time-dependent changes in individual sham animals. Finally, circulating GFAP was associated with histopathological markers of diffuse axonal injury and blood-brain barrier breach, as well as variations in device kinematics following TBI+HS. Current findings therefore highlight the need to directly quantify injury biomechanics with head mounted sensors and suggest that GFAP, NfL, and UCH-L1 are sensitive to multiple forms of trauma rather than having a single pathological indication (e.g., GFAP = astrogliosis).

Peritoneal dialysis in the setting of acute brain injury: an underappreciated modality

INTRODUCTION

Dialysis is complicated in the setting of acute brain injury (ABI) due to several factors including acute solute shifts, acid base changes, need for anticoagulation, and changes in intracranial pressure. For these reasons, continuous renal replacement therapy (CRRT) is often the chosen modality for renal replacement needs in these patients. Peritoneal dialysis (PD) is less discussed but shares many of the benefits often attributed to CRRT. We describe, from both nephrology and neurosurgical perspectives, a case successfully managed with PD.

CASE

A 25-year-old male with history of end-stage kidney disease (ESKD) secondary to focal segmental glomerulosclerosis on continuous cycling PD for 5 years presented to the hospital with headache and altered mental status. Initial imaging revealed a large intraventricular hemorrhage extending to the fourth ventricle. He underwent an emergent right depressive hemicraniectomy and clot evacuation. Post-operative imaging revealed worsening cerebral edema, intraventricular hemorrhage, and hydrocephalus. The decision was made to continue PD, noting that it retains many of the benefits of CRRT (which it is in fact, a form of) which he tolerated well until the need for a percutaneous gastrostomy tube arose. He was transiently transitioned to hemodialysis but returned to PD once his gastrostomy healed. He continued PD for 1 year without complication and eventually received a kidney transplant.

DISCUSSION

In managing patients with ABI undergoing dialysis, a number of considerations must be undertaken including avoidance of hypotension to maintain cerebral perfusion pressure and minimize ischemia reperfusion injury, avoidance of anticoagulants that can precipitate or worsen bleeding, the potential for cerebral edema due to rapid solute clearance and osmotic dissipation of therapeutic hypernatremia, and the mitigation of intracellular acidosis from bicarbonate delivery. Although underutilized, PD may potentially serve as a viable option for dialysis in the setting of ABI as demonstrated by the case presented.