Brain-Heart Interactions in Traumatic Brain Injury

Echocardiogram utilization in hospitalized adults with isolated traumatic brain injury: Propensity-matched analysis of the national inpatient sample 2016-2020

BACKGROUND

Early left ventricular systolic dysfunction is common after moderate-severe traumatic brain injury (TBI). Echocardiography (Echo) can evaluate cardiac function across various clinical scenarios; however, its utilization in isolated TBI remains poorly understood. To address this gap, we aim to examine Echo utilization in hospitalized adults with isolated TBI.

METHODS

Using a propensity-matched cohort based on All Patient Refined Diagnosis Related Group severity of illness, we performed a multivariable logistic regression analysis (adjusting for demographics, admitting hospital characteristics, TBI characteristics, cardiac comorbidities, and cardiac complications) to examine factors associated with Echo utilization in patients with isolated TBI in the US National Inpatient Sample (2016-2020). We reported adjusted odds ratio (aOR) and 95% confidence intervals.

RESULTS

In 4874 patients matched by APR-DRG severity of illness, the factors associated with Echo utilization were as follows: Older age compared to 18-44 years, Urban teaching hospital: aOR 1.44 [1.05;1.98], TBI associated with syncope: 3.29 [2.68;4.07], ICP monitoring: 2.26 [1.18, 4.45), hypertension: 1.35 [1.18, 1.54], myocardial infarction: 2.89 [2.14, 3.94], atrial fibrillation:1.38 [1.10, 1.74], heart failure: 1.57 [1.31, 1.87], ventricular tachycardia: 1.85 [1.28, 2.71), and pulmonary embolism: 2.61 [1.51, 4.66].

CONCLUSIONS

Echo utilization was associated with TBI etiology, pre-existing cardiac comorbidities, and in-hospital cardiac complications. These findings need validation in prospective studies.

Effect of β-blocker on clinical outcomes in patients with traumatic brain injury: a retrospective propensity-matched study

Background

Traumatic brain injury (TBI) represents a significant public health challenge due to its complex management. β-blockers may offer neuroprotective benefits, but their impact on TBI outcomes remains unclear. This study aims to evaluate the effect of β-blocker use on clinical outcomes in TBI patients.

Methods

This retrospective cohort study included adult TBI patients, categorized into β-blocker and non-β-blocker groups. Propensity score matching (PSM) was utilized to balance baseline characteristics. Mortality was assessed through the application of multivariable Cox regression models and Kaplan-Meier survival curves. Subgroup analyses examined the consistency of the results.

Results

A total of 1,516 patients were included in the study, with 750 receiving β-blocker therapy and 766 not receiving it. After PSM, 473 pairs of patients were matched. The analysis indicated that β-blockers significantly reduce 28-day mortality (HR 0.43, 95% CI: 0.31-0.60, P < 0.001). However, patients receiving β-blocker had considerably longer hospital stays (7.89 days vs. 5.45 days, P < 0.001) and ICU stays (2.94 days vs. 2.33 days, P < 0.001).

Conclusion

β-blocker therapy is associated with improved short-term outcomes in patients with TBI, particularly in those with mild (GCS 13-15) and severe (GCS 3-8) TBI. However, no significant benefit was observed in patients with moderate TBI (GCS 9-12). This therapy may also prolong hospital and ICU stays.

Dynamic assessment of signal entropy for prognostication and secondary brain insult detection after traumatic brain injury

BACKGROUND

Entropy quantifies the level of disorder within a system. Low entropy reflects increased rigidity of homeostatic feedback systems possibly reflecting failure of protective physiological mechanisms like cerebral autoregulation. In traumatic brain injury (TBI), low entropy of heart rate and intracranial pressure (ICP) predict unfavorable outcome. Based on the hypothesis that entropy is a dynamically changing process, we explored the origin and value of entropy time trends.

METHODS

232 continuous recordings of arterial blood pressure and ICP of TBI patients with available clinical information and 6-month outcome (Glasgow Outcome Scale) were accessed form the Brain Physics database. Biosignal entropy was estimated as multiscale entropy (MSE) that aggregates entropy at several time scales (20 coarse graining steps starting from 0.1 Hz). MSE was calculated repeatedly for consecutive, overlapping 6 h segments. Percentage monitoring time (ptime) or dosage (duration*level/hour) below different cutoffs were evaluated against outcome using univariable and multivariable analyses, and propensity score matching. Associations to clinical and monitoring metrics were explored using correlation coefficients. Lastly, individual secondary brain insults (deviations in ICP, cerebral perfusion pressure - CPP, or pressure reactivity) were assessed in relation to changes in MSE.

RESULTS

Increased MSE abp and MSE cpp ptime (OR 1.28 (1.07-1.58) and OR 1.50 (1.16-2.03) for MSE abp and cpp respectively) and dose (OR 1.12 (1.02-1.27) and OR 1.21 (1.06-1.46) for MSE abp and cpp respectively) were associated with poor outcome even after propensity score matching within multivariable models correcting for ICP, CPP, and the pressure reactivity index. MSE trajectories differed significantly dependent on outcome. The entropy metrics displayed weak correlations to clinical parameters. Individual episodes of deranged physiology were associated with decreases in the MSE metrics from both cerebral and systemic biosignals.

CONCLUSIONS

Biosignal entropy of changes dynamically after TBI. The assessment of these variations augments individualized, dynamic, outcome prognostication and identification of secondary cerebral insults. Additionally, these explorations allow for further exploitation of the extensive physiological data lakes acquired for each TBI patient within an intensive care environment.

Total Antioxidant Status in Critically Ill Patients with Traumatic Brain Injury and Secondary Organ Failure-A Systematic Review

Introduction: The available literature indicates that oxidant-antioxidant imbalance plays a significant role in the pathophysiology of traumatic brain injury and the subsequent secondary organ dysfunctions. However, there is a lack of studies summarizing the knowledge in this area, and no clear guidelines exist regarding the use of biomarkers of oxidative stress as diagnostics tools. Methods: The present work aims to provide a systematic review of the literature on the use of total antioxidant capacity (TAC) assays in predicting the outcomes of traumatic brain injury (TBI). A literature search was conducted up to 1 September 2024, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) guidelines, using the PubMed and Scopus databases. Based on the inclusion criteria, 24 studies were used for the final review. Results: Promising data indicate that TAC assays are useful in predicting 30-day mortality and neurological outcomes. Moreover, they correlate with radiological findings on CT scans in brain injury and the clinical classifications of injuries, as well as the parameters of organ failure. Conclusions: Total antioxidant capacity assays can be used to assess the extent of brain damage and prognosticate general vital functions. Future experiments should include long-term randomized clinical trials on larger populations of TBI patients.

Extracranial Complications in Monitored and Nonmonitored Patients with Traumatic Brain Injury in the BEST TRIP Trial and a Companion Observational Cohort

INTRODUCTION

Extracranial complications occur commonly in patients with traumatic brain injury (TBI) and can have implications for patient outcome. Patient-specific risk factors for developing these complications are not well studied, particularly in low and middle-income countries (LMIC). The study objective was to determine patient-specific risk factors for development of extracranial complications in TBI.

METHODS

We assessed the relationship between patient demographic and injury factors and incidence of extracranial complications using data collected September 2008-October 2011 from the BEST TRIP trial, a randomized controlled trial assessing TBI management protocolized on intracranial pressure (ICP) monitoring versus imaging and clinical exam, and a companion observational patient cohort.

RESULTS

Extracranial infections (55%), respiratory complications (19%), hyponatremia (27%), hypernatremia (27%), hospital acquired pressure ulcers (6%), coagulopathy (9%), cardiac arrest (10%), and shock (5%) occurred at a rate of ≥5% in our study population; overall combined rate of these complications was 82.3%. Tracheostomy in the intensive care unit (P < 0.001), tracheostomy timing (P = 0.025), mannitol and hypertonic saline doses (P < 0.001), brain-specific therapy days and brain-specific therapy intensity (P < 0.001), extracranial surgery (P < 0.001), and neuroworsening with pupil asymmetry (P = 0.038) were all significantly related to the development of one of these complications by univariable analysis. Multivariable analysis revealed ICP monitor use and brain-specific therapy intensity to be the most common factors associated with individual complications.

CONCLUSIONS

Extracranial complications are common following TBI. ICP monitoring and treatment are related to extra-cranial complications. This supports the need for reassessing the risk-benefit balance of our current management approaches in the interest of improving outcome.

Systemic and cerebro-cardiac biomarkers following traumatic brain injury: an interim analysis of randomized controlled clinical trial of early administration of beta blockers

This is an interim analysis of the Beta-blocker (Propranolol) use in traumatic brain injury (TBI) based on the high-sensitive troponin status (BBTBBT) study. The BBTBBT is an ongoing double-blind placebo-controlled randomized clinical trial with a target sample size of 771 patients with TBI. We sought, after attaining 50% of the sample size, to explore the impact of early administration of beta-blockers (BBs) on the adrenergic surge, pro-inflammatory cytokines, and the TBI biomarkers linked to the status of high-sensitivity troponin T (HsTnT). Patients were stratified based on the severity of TBI using the Glasgow coma scale (GCS) and HsTnT status (positive vs negative) before randomization. Patients with positive HsTnT (non-randomized) received propranolol (Group-1; n = 110), and those with negative test were randomized to receive propranolol (Group-2; n = 129) or placebo (Group-3; n = 111). Propranolol was administered within 24 h of injury for 6 days, guided by the heart rate (> 60 bpm), systolic blood pressure (≥ 100 mmHg), or mean arterial pressure (> 70 mmHg). Luminex and ELISA-based immunoassays were used to quantify the serum levels of pro-inflammatory cytokines (Interleukin (IL)-1β, IL-6, IL-8, and IL-18), TBI biomarkers [S100B, Neuron-Specific Enolase (NSE), and epinephrine]. Three hundred and fifty patients with comparable age (mean 34.8 ± 9.9 years) and gender were enrolled in the interim analysis. Group 1 had significantly higher baseline levels of IL-6, IL-1B, S100B, lactate, and base deficit than the randomized groups (p = 0.001). Group 1 showed a significant temporal reduction in serum IL-6, IL-1β, epinephrine, and NSE levels from baseline to 48 h post-injury (p = 0.001). Patients with severe head injuries had higher baseline levels of IL-6, IL-1B, S100B, and HsTnT than mild and moderate TBI (p = 0.01). HsTnT levels significantly correlated with the Injury Severity Score (ISS) (r = 0.275, p = 0.001), GCS (r = - 0.125, p = 0.02), and serum S100B (r = 0.205, p = 0.001). Early Propranolol administration showed a significant reduction in cytokine levels and TBI biomarkers from baseline to 48 h post-injury, particularly among patients with positive HsTnT, indicating the potential role in modulating inflammation post-TBI.Trial registration: ClinicalTrials.gov NCT04508244. It was registered first on 11/08/2020. Recruitment started on 29 December 2020 and is ongoing. The study was partly presented at the 23rd European Congress of Trauma and Emergency Surgery (ECTES), April 28-30, 2024, in Estoril, Lisbon, Portugal.

Associations of serum lactate and lactate clearance with delirium in the early stage of ICU: a retrospective cohort study of the MIMIC-IV database

Aim

This study aimed to investigate the associations of serum lactate level [within and after 24 h of the intensive care unit (ICU) admission] and lactate clearance rate with delirium and assess associations of lactate and lactate clearance rate with 30-day mortality in delirium patients.

Methods

Data in this retrospective cohort study were extracted from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database in 2012-2019. The associations of lactate and lactate clearance rate with delirium were explored through univariable and multivariable logistic regression analyses, whereas the associations of lactate and lactate clearance rate with 30-day mortality in delirium patients were investigated using univariable and multivariable Cox regression analyses. Subgroup analysis was performed for age, gender, sepsis, hypertension, sedative drug, ventilation, antibiotic drug, vasopressors, and the Sequential Organ Failure Assessment (SOFA) score. The evaluation indexes were odds ratios (ORs), hazard ratios (HRs), and 95% confidence intervals (CIs).

Results

Among 7,812 (14.58%) eligible participants, 4,338 (8.19%) had delirium and 1,903 (24.36%) died within 30 days. After adjusting for covariates, patients with lactic acidosis (lactate level > 5 mmol/L and PH < 7.35) at T0 (within 24 h of the ICU admission) had higher odds of delirium (OR = 1.235, 95%CI: 1.105-1.382). Hyperlactatemia (lactate level 2-5 mmol/L and PH > 7.35) at T1 (after 24 h of the ICU admission) was also associated with higher odds of delirium (OR = 1.277, 95%CI: 1.126-1.447). Lactate clearance rate > 50% was linked to lower odds of delirium (OR = 0.705, 95%CI: 0.613-0.811), and this relationship was also observed in ≥65 years old, female, male, non-sepsis, sepsis, non-hypertension, non-sedative drug use, sedative drug use, ventilation, antibiotic drug use, use of vasopressors, and different SOFA score subgroups (all p < 0.05). Additionally, hyperlactatemia and lactic acidosis (whether at T0 or T1) may be potential risk factors for 30-day mortality in delirium patients, whereas lactate clearance rate ≥ 0 had a potential protective effect on 30-day mortality (all p < 0.05).

Conclusion

Higher serum lactate levels in the early stage of the ICU were associated with a higher risk of delirium and subsequent mortality. Measures taken to increase the lactate clearance rate are necessary to reduce potential delirium or mortality risk in clinical settings. However, more evidence from prospective studies is needed to verify these findings.

Crosstalk Between the Nervous System and Systemic Organs in Acute Brain Injury

Organ crosstalk is a complex biological communication between distal organs mediated via cellular, soluble, and neurohormonal actions, based on a two-way pathway. The communication between the central nervous system and peripheral organs involves nerves, endocrine, and immunity systems as well as the emotional and cognitive centers of the brain. Particularly, acute brain injury is complicated by neuroinflammation and neurodegeneration causing multiorgan inflammation, microbial dysbiosis, gastrointestinal dysfunction and dysmotility, liver dysfunction, acute kidney injury, and cardiac dysfunction. Organ crosstalk has become increasingly popular, although the information is still limited. The present narrative review provides an update on the crosstalk between the nervous system and systemic organs after acute brain injury. Future research might help to target this pathophysiological process, preventing the progression toward multiorgan dysfunction in critically ill patients with brain injury.

Traumatic brain injury and risk of heart failure and coronary heart disease: A nationwide population-based cohort study

BACKGROUND

This study examined the long-term risks of heart failure (HF) and coronary heart disease (CHD) following traumatic brain injury (TBI), focusing on gender differences.

METHODS

Data from Taiwan's National Health Insurance Research Database included 29,570 TBI patients and 118,280 matched controls based on propensity scores.

RESULTS

The TBI cohort had higher incidences of CHD and HF (9.76 vs. 9.07 per 1000 person-years; 4.40 vs. 3.88 per 1000 person-years). Adjusted analyses showed a significantly higher risk of HF in the TBI group (adjusted hazard ratio = 1.08, 95% CI = 1.01-1.17, P = 0.031). The increased CHD risk in the TBI cohort became insignificant after adjustment. Subgroup analysis by gender revealed higher HF risk in men (aHR = 1.14, 95% CI = 1.03-1.25, P = 0.010) and higher CHD risk in women under 50 (aHR = 1.32, 95% CI = 1.15-1.52, P < 0.001). TBI patients without beta-blocker therapy may be at increased risk of HF.

CONCLUSION

Our results suggest that TBI increases the risk of HF and CHD in this nationwide cohort of Taiwanese citizens. Gender influences the risks differently, with men at higher HF risk and younger women at higher CHD risk. Beta-blockers have a neutral effect on HF and CHD risk.

High Plasma Fibrinogen Level Elevates the Risk of Cardiac Complications Following Spontaneous Intracerebral Hemorrhage

BACKGROUND

Cardiac complications are related to poor prognosis after spontaneous intracerebral hemorrhage (ICH). This study aims to predict the cardiac complications arising from small intracranial hematoma at ultraearly stage.

METHODS

The data of this work were derived from the Risk Stratification and Minimally Invasive Surgery in Acute ICH Patients study (ClinicalTrials.gov Identifier: NCT03862729). This work included patients with ICH but without brain herniation, as confirmed by a brain computed tomography scan within 48 hours of symptom onset. Every Patient's information recorded at the emergent department, including clinical, laboratory, electrocardiogram, and medical records, was derived from the electronic data capture. Cardiac complications were defined as the occurrence of myocardial damage, arrhythmias, and ischemic electrocardiogram changes during hospitalization. Variables associated with cardiac complications were filtrated by univariate and multivariate regression analyses. Independent risk factors were used to form the early predictive model. The restricted cubic splines were employed to investigate the nonlinear associations in a more sophisticated and scholarly manner.

RESULTS

A total of 587 ICH patients were enrolled in this work, including 72 patients who suffered from cardiac complications after ICH. Out of the 78 variables, 24 were found to be statistically significant in the univariate logistic regression analysis. These significant variables were then subjected to multivariate logistic regression analysis and utilized for constructing risk models. Multivariate logistic regression analysis showed high plasma fibrinogen (FIB) level [odds ratio (OR) per standard deviation (SD) 1.327, 95% confidence intervals (CI) 1.037-1.697; P = 0. 024)] and older age (OR per SD 1.777, 95% CI 1.344-2.349; P ＜0.001) were associated with a higher incidence of cardiac complications after ICH. High admission pulse rate (OR 0.620, 95% CI 0.451-0.853; P = 0. 003) was considered a protective factor for cardiac complications after ICH. In the restricted cubic spline regression model, FIB and cardiac complications following ICH were positively correlated and almost linearly (P for nonlinearity = 0.073). The reference point for FIB in predicting cardiac complications after ICH was 2.64 g/L.

CONCLUSIONS

Emergent factors, including plasma FIB level, age, and pulse rate, might be independently associated with cardiac complications after ICH, which warrants attention in the context of treatment.

Incidence of Myocardial Injury and Cardiac Dysfunction After Adult Traumatic Brain Injury: A Systematic Review and Meta-analysis

Myocardial injury and cardiac dysfunction after traumatic brain injury (TBI) have been reported in observational studies, but there is no robust estimate of their incidences. We conducted a systematic review and meta-analysis to estimate the pooled incidence of myocardial injury and cardiac dysfunction among adult patients with TBI. A literature search was conducted using MEDLINE and EMBASE databases from inception to November 2022. Observational studies were included if they reported at least one abnormal electrocardiographic finding, elevated cardiac troponin level, or echocardiographic evaluation of systolic function or left ventricular wall motion in adult patients with TBI. Myocardial injury was defined as elevated cardiac troponin level according to the original studies and cardiac dysfunction was defined as the presence of left ventricular ejection fraction <50% or regional wall motion abnormalities assessed by echocardiography. The meta-analysis of the pooled incidence of myocardial injury and cardiac dysfunction was performed using random-effect models. The pooled estimated incidence of myocardial injury after TBI (17 studies, 3,773 participants) was 33% (95% CI: 27%-39%, I2:s 93%), and the pooled estimated incidence of cardiac dysfunction after TBI (9 studies, 557 participants) was 16.% (95% CI: 9%-25.%, I2: 84%). Although there was significant heterogeneity between studies and potential overestimation of the incidence of myocardial injury and cardiac dysfunction, our findings suggest that myocardial injury occurs in approximately one-third of adults after TBI, and cardiac dysfunction occurs in approximately one-sixth of patients with TBI.

Iron overload enhances TBI-induced cardiac dysfunction by promoting ferroptosis and cardiac inflammation

Previous studies have proved that cardiac dysfunction and myocardial damage can be found in TBI patients, but the underlying mechanisms of myocardial damage induced by TBI can't be illustrated. We want to investigate the function of ferroptosis in myocardial damage after TBI and determine if inhibiting iron overload might lessen myocardial injury after TBI due to the involvement of iron overload in the process of ferroptosis and inflammation. We detect the expression of ferroptosis-related proteins in cardiac tissue at different time points after TBI, indicating that TBI can cause ferroptosis in the heart in vivo. The echocardiography and myocardial enzymes results showed that ferroptosis can aggravate TBI-induced cardiac dysfunction. The result of DHE staining and 4-HNE expression showed that inhibition of ferroptosis can reduce ROS production and lipid peroxidation in myocardial tissue. In further experiments, DFO intervention was used to explore the effect of iron overload inhibition on myocardial ferroptosis after TBI, the production of ROS, expression of p38 MAPK and NF-κB was detected to explore the effect of iron overload on myocardial inflammation after TBI. The results above show that TBI can cause heart ferroptosis in vivo. Inhibition of iron overload can alleviate myocardial injury after TBI by reducing ferroptosis and inflammatory response induced by TBI.

Predictive factors for cerebrocardiac syndrome in patients with severe traumatic brain injury: a retrospective cohort study

Background and objective

Cerebrocardiac syndrome (CCS) is a severe complication of severe traumatic brain injury (sTBI) that carries high mortality and disability rates. Early identification of CCS poses a significant clinical challenge. The main objective of this study was to investigate potential risk factors associated with the development of secondary CCS in patients with sTBI. It was hypothesized that elevated right heart Tei index (TI), lower Glasgow Coma Scale (GCS) scores, and elevated cardiac troponin-I (cTnI) levels would independently contribute to the occurrence of CCS in sTBI patients.

Methods

A retrospective cohort study was conducted to identify risk factors for CCS secondary to sTBI. One hundred and fifty-five patients were enrolled with sTBI admitted to the hospital between January 2016 and December 2020 and divided them into a CCS group (n = 75) and a non-CCS group (n = 80) based on the presence of CCS. This study involved the analysis and comparison of clinical data from two patient groups, encompassing demographic characteristics, peripheral oxygen saturation (SPO2), neuron-specific enolase (NSE), cardiac troponin-I (cTnI), N-terminal pro-brain natriuretic peptide (NT-proBNP), optic nerve sheath diameter (ONSD), cardiac ultrasound, acute physiology and chronic health evaluation (APACHE II) scores, and GCS scores and so on. Multivariate logistic regression was employed to identify independent risk factors for CCS, and receiver operating characteristic (ROC) curves were used to assess their predictive value for CCS secondary to sTBI.

Results

The study revealed that 48.4% of sTBI patients developed secondary CCS. In the multivariate analysis model 1 that does not include NT-proBNP and cTnI, ONSD (OR = 2.582, 95% CI: 1.054-6.327, P = 0.038), right heart Tei index (OR = 2.81, 95% CI: 1.288-6.129, P = 0.009), and GCS (OR = 0.212, 95% CI: 0.086-0.521, P = 0.001) were independent risk factors for secondary CCS in sTBI patients. In multivariate analysis model 2 that includes NT-proBNP and cTnI, cTnI (OR = 27.711, 95%CI: 3.086-248.795, P = 0.003), right heart Tei index (OR = 2.736, 95% CI: 1.056-7.091, P = 0.038), and GCS (OR = 0.147, 95% CI: 0.045-0.481, P = 0.002) were independent risk factors for secondary CCS in sTBI patients. The area under the ROC curve for ONSD, Tei index, GCS, and cTnI were 0.596, 0.613, 0.635, and 0.881, respectively. ONSD exhibited a positive predictive value (PPV) of 0.704 and a negative predictive value (NPV) of 0.634. The Tei index demonstrated a PPV of 0.624 and an NPV of 0.726, while GCS had a PPV of 0.644 and an NPV of 0.815. On the other hand, cTnI exhibited a significantly higher PPV of 0.936 and an NPV of 0.817. These findings indicate that the Tei index, GCS score, and cTnI possess certain predictive value for secondary CCS in patients with sTBI.

Conclusions

The study provides valuable insights into the identification of independent risk factors for CCS secondary to sTBI. The findings highlight the significance of right heart Tei index, GCS score, and cTnI as potential predictive factors for CCS in sTBI patients. Further larger-scale studies are warranted to corroborate these findings and to provide robust evidence for the development of early intervention strategies aimed at reducing the incidence of CCS in this patient population.

Cardiac Point-of-Care Ultrasound in Pediatric Neurocritical Care: A Case Series

BACKGROUND

Pediatric brain injury is accompanied by hemodynamic perturbations complicating the optimization of cerebral physiology. Point-of-care ultrasound (POCUS) uses dynamic real-time imaging to complement the physical examination and identify hemodynamic abnormalities in preload, contractility, and afterload conditions, but the contribution of cardiac POCUS in the context of pediatric brain injury is unclear.

METHODS

We reviewed cardiac POCUS images integrated in clinical care to examine those with neurological injury and hemodynamic abnormalities.

RESULTS

We discuss three children with acute brain injury and myocardial dysfunction identified using cardiac POCUS by bedside clinicians.

CONCLUSIONS

Cardiac POCUS may have an important role in caring for children with neurologic injury. These patients received personalized care informed by POCUS data in attempts to stabilize hemodynamics and optimize clinical outcomes.

Impact of Serum Lactate as an Early Serum Biomarker for Cardiopulmonary Parameters within the First 24 Hours of Intensive Care Unit Treatment in Patients with Isolated Traumatic Brain Injury

OBJECTIVE

Cardiopulmonary (CP) complications are well-known phenomena in patients with isolated traumatic brain injury (iTBI) that can lead to tissue hypoperfusion and hypoxia. Serum lactate level is a well-known biomarker, indicating these systemic dysregulations in various diseases, but this has not been investigated in iTBI patients so far. The current study evaluates the association between serum lactate levels upon admission and CP parameters within the first 24 h of intensive care unit (ICU) treatment in iTBI patients.

PATIENTS AND METHODS

182 patients with iTBI who were admitted to our neurosurgical ICU between December 2014 and December 2016 were retrospectively evaluated. Serum lactate levels on admission, demographic, medical, and radiological data upon admission, as well as several CP parameters within the first 24 h of ICU treatment, were analyzed, as well as the functional outcome at discharge. The total study population was dichotomized into patients with an elevated serum lactate level (lactate-positive) and patients with a low serum lactate level (lactate-negative) upon admission.

RESULTS

69 patients (37.9%) had an elevated serum lactate level upon admission, which was significantly associated with a lower Glasgow Coma Scale score (p = 0.04), a higher head AIS score (p = 0.03), and a higher Acute Physiology and Chronic Health Evaluation II score (p = 0.01) upon admission, as well as a higher modified Rankin Scale score (p = 0.002) and a lower Glasgow Outcome Scale score (p < 0.0001) at discharge. Furthermore, the lactate-positive group required a significantly higher norepinephrine application rate (NAR; p = 0.04) and a higher fraction of inspired oxygen (FiO2; p = 0.04) to maintain the defined CP parameters within the first 24 h.

CONCLUSION

ICU-admitted iTBI patients with elevated serum lactate levels upon admission required higher CP support within the first 24 h of ICU treatment after iTBI. Serum lactate may be a helpful biomarker for improving ICU treatment in the early stages.

Distal and Proximal Predictors of Rehospitalization Over 10 Years Among Survivors of TBI: A National Institute on Disability, Independent Living, and Rehabilitation Research Traumatic Brain Injury Model Systems Study

OBJECTIVE

To describe the rates and causes of rehospitalization over a 10-year period following a moderate-severe traumatic brain injury (TBI) utilizing the Healthcare Cost and Utilization Project (HCUP) diagnostic coding scheme.

SETTING

TBI Model Systems centers.

PARTICIPANTS

Individuals 16 years and older with a primary diagnosis of TBI.

DESIGN

Prospective cohort study.

MAIN MEASURES

Rehospitalization (and reason for rehospitalization) as reported by participants or their proxies during follow-up telephone interviews at 1, 2, 5, and 10 years postinjury.

RESULTS

The greatest number of rehospitalizations occurred in the first year postinjury (23.4% of the sample), and the rates of rehospitalization remained stable (21.1%-20.9%) at 2 and 5 years postinjury and then decreased slightly (18.6%) at 10 years postinjury. Reasons for rehospitalization varied over time, but seizure was the most common reason at 1, 2, and 5 years postinjury. Other common reasons were related to need for procedures (eg, craniotomy or craniectomy) or medical comorbid conditions (eg, diseases of the heart, bacterial infections, or fractures). Multivariable logistic regression models showed that Functional Independence Measure (FIM) Motor score at time of discharge from inpatient rehabilitation was consistently associated with rehospitalization at all time points. Other factors associated with future rehospitalization over time included a history of rehospitalization, presence of seizures, need for craniotomy/craniectomy during acute hospitalization, as well as older age and greater physical and mental health comorbidities.

CONCLUSION

Using diagnostic codes to characterize reasons for rehospitalization may facilitate identification of baseline (eg, FIM Motor score or craniotomy/craniectomy) and proximal (eg, seizures or prior rehospitalization) factors that are associated with rehospitalization. Information about reasons for rehospitalization can aid healthcare system planning. By identifying those recovering from TBI at a higher risk for rehospitalization, providing closer monitoring may help decrease the healthcare burden by preventing rehospitalization.

Traumatic Brain Injury: Intraoperative Management and Intensive Care Unit Multimodality Monitoring

Traumatic brain injury is a devastating event associated with substantial morbidity. Pathophysiology involves the initial trauma, subsequent inflammatory response, and secondary insults, which worsen brain injury severity. Management entails cardiopulmonary stabilization and diagnostic imaging with targeted interventions, such as decompressive hemicraniectomy, intracranial monitors or drains, and pharmacological agents to reduce intracranial pressure. Anesthesia and intensive care requires control of multiple physiologic variables and evidence-based practices to reduce secondary brain injury. Advances in biomedical engineering have enhanced assessments of cerebral oxygenation, pressure, metabolism, blood flow, and autoregulation. Many centers employ multimodality neuromonitoring for targeted therapies with the hope to improve recovery.

Neuroprotective Effects of Milrinone on Acute Traumatic Brain Injury

BACKGROUND

Traumatic brain injury is still an important health problem worldwide. Traumatic brain injury not only causes direct mechanical damage to the brain but also induces biochemical changes that lead to secondary nerve cell loss. In this study, we investigated the neuroprotective effect of milrinone after traumatic brain injury (TBI) in a rat model.

METHODS

Forty male Wistar albino rats, were used. Rats were divided into 4 groups: 1) sham, 2) TBI, 3) TBI + Ringers, and 4) TBI + Milrinone. In group 1 (sham), only craniotomy was performed. In group 2 (TBI), TBI was performed after craniotomy. In group 3 (TBI + Ringer), TBI was performed after craniotomy and intraperitoneal Ringers solution was given immediately afterward. Group 4 (TBI + Milrinone), TBI was performed after craniotomy, and milrinone was given 1.0 mg/kg milrinone intraperitoneally directly (0.5 mg/kg milrinone intraperitoneally again 24 hours, 48 hours, and 72 hours after trauma). Tests were performed for neurological and neurobehavioral functions. Immunohistochemistry and histopathology studies were performed.

RESULTS

In group 4 compared with group 2 and group 3 groups, tests for neurological functions and neurobehavioral functions were significantly better. In the milrinone treatment used in group 4, plasma and brain tissue tumor necrosis factor, 8-OH 2-deoxyguanosine , and interleukin 6 levels were significantly decreased, and increased plasma and tissue IL-10 levels were detected. Histopathological spinal cord injury and apoptotic index increased in groups 2 and 3, while significantly decreasing in group 4.

CONCLUSIONS

This study shows for the first time that the anti-inflammatory, antioxidant and antiapoptotic properties of milrinone may be neuroprotective after TBI.

Troponin I New Biomarker in Traumatic Brain Injury

Mortality in traumatic brain injury (TBI) is thought to be pathology in the heart-brain axis but its effect on the prognosis of traumatic brain injury remains unclear. Our study aimed to investigate the relationship between cardiac troponin I (cTnI) level and prognosis in TBI patients. Between January 2017 and May 2021, 480 patients diagnosed with TBI, who applied to the emergency department, were retrospectively included in this multicentric study. The databases of the hospitals were examined comprehensively and the demographic, clinical, laboratory, radiological, and therapeutic data and results of the patients were obtained. The severity of trauma and clinical status was evaluated with AIS, Injury Severity Score (ISS), ASA physical status, and Glasgow Coma Scale (GCS). The severity of the trauma was evaluated with the ISS. The modified Rankin Scale (mRS) and the Glasgow Outcome Scale (GOS) at discharge were used to evaluate in-hospital clinical outcomes. cTnI levels were classified into three categories: normal (< 0.05 ng/ml), mildly elevated (0.05–0.99 ng/ml), and severely elevated (≥ 1 ng/ml). The mean age of the patients was 41.7 and 75.4% of them were men. It was observed that mortality among patients over 65 years (13.9%) increased. High cTnI was detected in 284 (59.1%) patients. Although it was not statistically significant regarding the elevation of cTnI in patients under 65 years of age (P = 0.62), the difference was significant for cTnI in patients over 65 years of age (P < 0.001). The relationship between cTnI elevation was found to be statistically significant (P < 0.001) as the severity of the trauma increased and when severe additional traumas (thoracic, abdominal, or pelvic) occurred. A high cTnI level is associated with poor prognosis in TBI patients. cTnI measurement is a useful tool for early risk stratification and accelerated care; however, further prospective studies are needed.

The prognostic value of cardiac troponin T in different age groups of traumatic brain injury patients

BACKGROUND

The cardiac dysfunction has been confirmed as a common non-neurological complication and associated with increased mortality in traumatic brain injury (TBI) patients. As a biological marker of cardiac injury, the cardiac troponin T (TnT) has been verified correlated with the outcome of some non-traumatic brain injury patients. However, the prognostic value of TnT in TBI patients has not been clearly illustrated. We designed this study to explore the association between TnT and the outcome of TBI patients in different age subgroups.

METHODS

Patients diagnosed with TBI in a prospective critical care database were eligible for this study. Univariate logistic regression analysis was firstly performed to explore the relationship between included variables and mortality. Then, the real effect of TnT on the outcome of different age subgroups was analyzed by multivariate logistic regression analysis adjusting the confounding effects of other significant risk factors. Finally, we draw receiver operating characteristic (ROC) curves to evaluate the prognostic value of TnT in different age groups of TBI patients.

RESULTS

520 patients were included in this study with a mortality rate of 20.2%. There were 112 (21.5%) non-elderly patients (age < 65) and 408 (78.5%) elderly patients (age ≥ 65). Non-survivors had a higher percentage of previous acute myocardial infarction (p = 0.019) and pupil no-reaction (p = 0.028; p = 0.011) than survivors. Survivors had higher GCS (p < 0.001) and lower TnT than non-survivors (p < 0.001). TnT was significantly associated with mortality in non-elderly patients (p = 0.031) but not in overall patients (p = 0.143) and elderly patients (p = 0.456) in multivariate logistic regression analysis. The AUC (area under the ROC curve) value of TnT in overall, non-elderly and elderly patients was 0.644, 0.693 and 0.632, respectively. Combining TnT with GCS increased the sensitivity of predicting the poor outcome in both non-elderly and elderly TBI patients.

CONCLUSION

The prognostic value of TnT differed between elderly and non-elderly TBI patients. Level of TnT was associated with mortality of non-elderly TBI patients but not elderly patients. Combining the TnT with GCS could increase the sensitivity of prognosis evaluation.

Cardiac Troponin, Cognitive Function, and Dementia: A Systematic Review

Elevated cardiac troponin, a biomarker of myocardial injury, has been found in individuals with brain damage and lower cognitive function. We conducted a systematic review to examine the association of troponin with cognitive function, incidence of dementia and dementia-related outcomes. PubMed, Web of Science and EMBASE were searched from inception to August 2022. Inclusion criteria were: (i) population-based cohort studies; (ii) troponin measured as determinant; and (iii) cognitive function in any metric or diagnosis of any type of dementia or dementia-related measures as outcomes. Fourteen studies were identified and included, with a combined total of 38,286 participants. Of these studies, four examined dementia-related outcomes, eight studies examined cognitive function, and two studies examined both dementia-related outcomes and cognitive function. Studies report higher troponin to be associated with higher prevalence of cognitive impairment (n=1), incident dementia (n=1), increased risk of dementia hospitalization (specifically due to vascular dementia) (n=1), but not with incident Alzheimer's Disease (n=2). Majority of studies on cognitive function found elevated troponin also associated with worse global cognitive function (n=3), attention (n=2), reaction time (n=1) and visuomotor speed (n=1), both cross-sectionally and prospectively. Evidence regarding the association between higher troponin and memory, executive function, processing speed, language and visuospatial function was mixed. This was the first systematic review on the association between troponin, cognitive function, and dementia. Higher troponin is associated with subclinical cerebrovascular damage and might act as a risk-marker of cognitive vulnerability.

Beta blocker use in traumatic brain injury based on the high-sensitive troponin status (BBTBBT): methodology and protocol implementation of a double-blind randomized controlled clinical trial

Background

Beta-adrenergic receptor blockers (BB) play an important role in the protection of organs that are susceptible for secondary injury due to stress-induced adrenergic surge. However, the use of BB in traumatic brain injury (TBI) patients is not yet the standard of care which necessitates clear scientific evidence to be used. The BBTBBT study aims to determine whether early administration of propranolol based on the high-sensitive troponin T(HsTnT) status will improve the outcome of TBI patients. We hypothesized that early propranolol use is effective in reducing 10- and 30-day mortality in TBI patients. Secondary outcomes will include correlation between serum biomarkers (troponin, epinephrine, cytokines, enolase, S100 calcium binding protein B) and the severity of injury and the impact of BB use on the duration of hospital stay and functional status at a 3-month period.

Methods

The BBTBBT study is a prospective, randomized, double-blinded, placebo-controlled three-arm trial of BB use in mild-to-severe TBI patients based on the HsTnT status. All enrolled patients will be tested for HsTnT at the first 4 and 6 h post-injury. Patients with positive HsTnT will receive BB if there is no contraindication (group 1). Patients with negative HsTnT will be randomized to receive either propranolol (group 2) or placebo (group 3). The time widow for receiving the study treatment is the first 24 h post-injury.

Discussion

Early BB use may reduce the catecholamine storm and subsequently the cascade of immune and inflammatory changes associated with TBI. HsTnT could be a useful fast diagnostic and prognostic tool in TBI patients. This study will be of great clinical interest to improve survival and functional outcomes of TBI patients.

Trial registration

ClinicalTrials.gov NCT04508244. Registered on 7 August 2020. Recruitment started on 29 December 2020 and is ongoing.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05872-8.

Neurogenic Stunned Myocardium Following an Attempt to Pass a Drug Test

Ingestion of a large volume of free water or other hypotonic solution can cause acute hyponatremia, leading to multiorgan dysfunction. Individuals may attempt to generate a false-negative urine drug screen through increased free water consumption leading to acute hyponatremia requiring emergency medical care. We present the case of a 19-year-old male who presented to a community emergency department for altered mental status after an attempt to generate a false-negative urine drug screen. He ingested a large volume of free water and multiple detoxification solutions, causing acute hyponatremia with resultant cerebral edema and neurogenic stunned myocardium. He required extracorporeal membrane oxygenation therapy with complete recovery of neurologic and cardiac function. Acute hyponatremia from excess free water consumption is a well-documented phenomenon that all emergency providers should be aware of. Prompt identification and management of acute hyponatremia are essential to prevent potentially severe, devastating sequelae, including cerebral edema and cardiopulmonary failure.In addition, extracorporeal membrane oxygenation may be considered in patients with cardiopulmonary failure in the setting of reversible cardiomyopathy, as evidenced in our case.

Endothelial glycocalyx in traumatic brain injury associated coagulopathy: potential mechanisms and impact

Traumatic brain injury (TBI) remains one of the leading causes of death and disability worldwide; more than 10 million people are hospitalized for TBI every year around the globe. While the primary injury remains unavoidable and not accessible to treatment, the secondary injury which includes oxidative stress, inflammation, excitotoxicity, but also complicating coagulation abnormalities, is potentially avoidable and profoundly affects the therapeutic process and prognosis of TBI patients. The endothelial glycocalyx, the first line of defense against endothelial injury, plays a vital role in maintaining the delicate balance between blood coagulation and anticoagulation. However, this component is highly vulnerable to damage and also difficult to examine. Recent advances in analytical techniques have enabled biochemical, visual, and computational investigation of this vascular component. In this review, we summarize the current knowledge on (i) structure and function of the endothelial glycocalyx, (ii) its potential role in the development of TBI associated coagulopathy, and (iii) the options available at present for detecting and protecting the endothelial glycocalyx.

Inversion of T Waves on Admission is Associated with Mortality in Spontaneous Intracerebral Hemorrhage

INTRODUCTION

Cardiac dysfunction directly caused by spontaneous intracerebral hemorrhage (ICH) is a poorly understood phenomenon, and its impact on outcome is still uncertain. The aim of this study is to investigate the relationship between electrocardiographic (EKG) abnormalities and mortality in ICH.

METHODS

This is a retrospective study analyzing EKG patterns on admission in patients admitted with ICH at a tertiary care center over an eight-year period. For each patient, demographics, medical history, clinical presentation, EKG on admission and during hospitalization, and head CT at presentation were reviewed. Mortality was noted.

RESULTS

A total of 301 ICH patients were included in the study. The most prevalent EKG abnormalities were QTc prolongation in 56% of patients (n = 168) followed by inversion of T waves (TWI) in 37% of patients (n = 110). QTc prolongation was associated with ganglionic location (p = 0.03) and intraventricular hemorrhage (IVH) (p = 0.01), TWIs were associated with ganglionic location (p = 0.02), and PR prolongation was associated with IVH (p = 0.01), while QRS prolongation was associated with lobar location (p < 0.01). Volume of ICH, hemispheric laterality, and involvement of insular cortex were not correlated with specific EKG patterns. In a logistic regression model, after correcting for ICH severity and prior cardiac history, presence of TWI was independently associated with mortality (OR: 3.04, CI:1.6-5.8, p < 0.01). Adding TWI to ICH score improved its prognostic accuracy (AUC 0.81, p = 0.04). Disappearance of TWI during hospitalization did not translate into improvement of survival (p = 0.5).

CONCLUSION

Presence of TWI on admission is an independent and unmodifiable factor associated with mortality in ICH. Further research is needed to elucidate the pathophysiologic mechanisms underlying electrocardiographic changes after primary intracerebral hemorrhage.

β-Blockers for traumatic brain injury: A systematic review and meta-analysis

BACKGROUND

Paroxysmal sympathetic hyperactivity (PSH) and catecholamine surge, which are associated with poor outcome, may be triggered by traumatic brain injury (TBI).β Adrenergic receptor blockers (β-blockers), as potential therapeutic agents to prevent paroxysmal sympathetic hyperactivity and catecholamine surge, have been shown to improve survival after TBI. The principal aim of this study was to investigate the effect of β-blockers on outcomes in patients with TBI.

METHODS

For this systematic review and meta-analysis, we searched MEDLINE, EMBASE, and Cochrane Library databases from inception to September 25, 2020, for randomized controlled trials, nonrandomized controlled trials, and observational studies reporting the effect of β-blockers on the following outcomes after TBI: mortality, functional measures, and cardiopulmonary adverse effects of β-blockers (e.g., hypotension, bradycardia, and bronchospasm). With use of random-effects model, we calculated pooled estimates, confidence intervals (CIs), and odds ratios (ORs) of all outcomes.

RESULTS

Fifteen studies with 12,721 patients were included. Exposure to β-blockers after TBI was associated with a significant reduction in adjusted in-hospital mortality (OR, 0.39; 95% CI, 0.30-0.51; I2 = 66.3%; p < 0.001). β-Blockers significantly improved the long-term (≥6 months) functional outcome (OR, 1.75; 95% CI, 1.09-2.80; I2 = 0%; p = 0.02). Statistically significant difference was not seen for cardiopulmonary adverse events (OR, 0.91; 95% CI, 0.55-1.50; I2 = 25.9%; p = 0.702).

CONCLUSION

This meta-analysis demonstrated that administration of β-blockers after TBI was safe and effective. Administration of β-blockers may therefore be suggested in the TBI care. However, more high-quality trials are needed to investigate the use of β-blockers in the management of TBI.

LEVEL OF EVIDENCE

Systematic review and meta-analysis, level III.

Changes in Subendocardial Viability Ratio in Traumatic Brain Injury Patients

Background: Traumatic brain injury (TBI) is often associated with cardiac dysfunction, which is a consequence of the brain-heart cross talk. The subendocardial viability ratio (SEVR) is an estimate of myocardial perfusion. The aim of this study was to analyze changes in the SEVR in patients with severe TBI without previous cardiac diseases. Methods: Adult patients treated for severe TBI with a Glasgow coma score <8 were studied. Pressure waveforms were obtained by a high-fidelity tonometer in the radial artery for SEVR calculation at five time points: immediately after admission to the intensive care unit and 24, 48, 72, and 96 h after admission. SEVRs and other clinically important parameters were analyzed in patients who survived and did not survive after 28 days of treatment, as well as in patients who underwent decompressive craniectomy (DC). Results: A total of 64 patients (16 females and 48 males) aged 18-64 years were included. Fifty patients survived and 14 died. DC was performed in 23 patients. SEVRs decreased 24 h after admission in nonsurvivors (p < 0.05) and after 48 h in survivors (p < 0.01) and its values were significantly lower in nonsurvivors than in survivors at 24, 72, and 96 h from admission (p < 0.05). The SEVR increased following DC (p < 0.05). Conclusions: A decreased SEVR is observed in TBI patients. Surgical decompression increases the SEVR, indicating improvement in coronary microvascular perfusion. The results of our study seem to confirm that brain injury affects myocardium function.

iTRAQ-based proteomic profiling reveals protein alterations after traumatic brain injury and supports thyroxine as a potential treatment

Traumatic brain injury (TBI) is a primary cause of disability and death across the world. Previously, RNA analysis was widely used to study the pathophysiological mechanisms underlying TBI; however, the relatively low correlation between the transcriptome and proteome revealed that RNA transcription abundance does not reliably predict protein abundance, which led to the emergence of proteomic research. In this study, an iTRAQ proteomics approach was applied to detect protein alterations after TBI on a large scale. A total of 3937 proteins were identified, and 146 proteins were significantly changed after TBI. Moreover, 23 upregulated proteins were verified by parallel reaction monitoring (PRM), and fold changes in 16 proteins were consistent with iTRAQ outcomes. Transthyretin (Ttr) upregulation has been demonstrated at the transcriptional level, and this study further confirmed this at the protein level. After treatment with thyroxine (T4), which is transported by Ttr, the effects of T4 on neuronal histopathology and behavioral performance were determined in vivo (TBI + T4 group). Brain edema was alleviated, and the integrity of the blood brain barrier (BBB) improved. Escape latency in the Morris water maze (MWM) declined significantly compared with the group without T4 treatment. Modified neurological severity scores (mNSS) of the TBI + T4 group decreased from day 1 to day 7 post-TBI compared with the TBI + saline group. These results indicate that T4 treatment has potential to alleviate pathologic and behavioral abnormalities post-TBI. Protein alterations after T4 treatment were also detected by iTRAQ proteomics. Upregulation of proteins like Lgals3, Gfap and Apoe after TBI were reversed by T4 treatment. GO enrichment showed T4 mainly affected intermediate filament organization, cholesterol transportation and axonal regeneration. In summary, iTRAQ proteomics provides information about the impact of TBI on protein alterations and yields insight into underlying mechanisms and pathways involved in TBI and T4 treatment. Finally, Ttr and other proteins identified by iTRAQ may become potential novel treatment targets post-TBI.

Effects of acute neurologic disease on the heart

Patients with acute neurologic disease often also have evidence of cardiac dysfunction. The cardiac dysfunction may result in a number of clinical signs including abnormal EKG changes, variations in blood pressure, development of cardiac arrhythmias, release of cardiac biomarkers, and reduced ventricular function. Although typically reversible, these cardiac complications are important to recognize as they are associated with increased morbidity and mortality. In this chapter, we discuss the suspected pathophysiology, clinical presentation, and management of the cardiac dysfunction that occur as a consequence of different types of acute neurologic illness.

Decompressive Craniectomy Improves QTc Interval in Traumatic Brain Injury Patients

BACKGROUND

Traumatic brain injury (TBI) is commonly associated with cardiac dysfunction, which may be reflected by abnormal electrocardiograms (ECG) and/or contractility. TBI-related cardiac disorders depend on the type of cerebral injury, the region of brain damage and the severity of the intracranial hypertension. Decompressive craniectomy (DC) is commonly used to reduce intra-cranial hypertension (ICH). Although DC decreases ICH rapidly, its effect on ECG has not been systematically studied. The aim of this study was to analyze the changes in ECG in patients undergoing DC.

METHODS

Adult patients without previously known cardiac diseases treated for isolated TBI with DC were studied. ECG variables, such as: spatial QRS-T angle (spQRS-T), corrected QT interval (QTc), QRS and T axes (QRSax and Tax, respectively), STJ segment and the index of cardio-electrophysiological balance (iCEB) were analyzed before DC and at 12-24 h after DC. Changes in ECG were analyzed according to the occurrence of cardiac arrhythmias and 28-day mortality.

RESULTS

48 patients (17 female and 31 male) aged 18-64 were studied. Intra-cranial pressure correlated with QTc before DC (p < 0.01, r = 0.49). DC reduced spQRS-T (p < 0.001) and QTc interval (p < 0.01), increased Tax (p < 0.01) and changed STJ in a majority of leads but did not affect QRSax and iCEB. The iCEB was relatively increased before DC in patients who eventually experienced cardiac arrhythmias after DC (p < 0.05). Higher post-DC iCEB was also noted in non-survivors (p < 0.05), although iCEB values were notably heart rate-dependent.

CONCLUSIONS

ICP positively correlates with QTc interval in patients with isolated TBI, and DC for relief of ICH reduces QTc and spQRS-T. However, DC might also increase risk for life-threatening cardiac arrhythmias, especially in ICH patients with notably prolonged QTc before and increased iCEB after DC.

Utility of serum macrophage migration inhibitory factor as a potential biomarker for detection of cerebrocardiac syndrome following severe traumatic brain injury

BACKGROUND

Cerebrocardiac syndrome (CCS) is a common complication after severe traumatic brain injury (sTBI) and its occurrence obviously increases the risk of a poor outcome. Macrophage migration inhibitory factor (MIF) acts as an inflammatory cytokine and its circulating concentration are related to acute heart and brain injury. The aim of this study was to examine the association of serum concentration of MIF with posttraumatic CCS.

METHODS

From January 2016 to February 2019, 116 sTBI patients and 116 healthy controls with similar age and gender percentage were recruited. Relationship between serum MIF concentration and CCS was assessed using multivariate analysis.

RESULTS

Serum MIF concentration of patients were significantly higher than those among controls. Serum MIF concentration were intimately correlated with Glasgow coma scale scores (t = -5.553, P < 0.001) and serum C-reactive protein concentration (t = 5.320, P < 0.001) in a multivariate linear regression model. 61 patients (52.6%) displayed CCS. Under ROC curve analylsis, there was a strong discriminatory ability for CCS regarding serum MIF concentration (area under curve, 0.834; 95% confidence interval, 0.754-0.897). Serum MIF concentration were highly associated with CCS independent of other confounding factors (odds ratio, 5.608; 95% CI: 1.896-16.587).

CONCLUSIONS

Increased MIF in serum may be a useful biomarker for early detection of CCS after head trauma.

Bypassing TBI: Metabolic Surgery and the Link between Obesity and Traumatic Brain Injury-a Review

Obesity is a common outcome of traumatic brain injury (TBI) that exacerbates principal TBI symptom domains identified as common areas of post-TBI long-term dysfunction. Obesity is also associated with increased risk of later-life dementia and Alzheimer's disease. Patients with obesity and chronic TBI may be more vulnerable to long-term mental abnormalities. This review explores the question of whether weight loss induced by bariatric surgery could delay or perhaps even reverse the progression of mental deterioration. Bariatric surgery, with its induction of weight loss, remission of type 2 diabetes, and other expressions of the metabolic syndrome, improves metabolic efficiency, leads to reversal of brain lesions seen on imaging studies, and improves function. These observations suggest that metabolic/bariatric surgery may be a most effective therapy for TBI.

Biomarkers for traumatic brain injury: a short review

Cellular response to TBI is a mixture of excitotoxicity, neuroinflammation, and cell death. Biomarkers that can track these lesions and inflammatory processes are being explored for their potential to provide objective measures in the evaluation of TBI, from prehospital care to rehabilitation. By understanding the pathways involved, we could be able to improve diagnostic accuracy, guide management, and prevent long-term disability. We listed some of the recent advances in this translational, intriguing, fast-growing field. Although the knowledge gaps are still significant, some markers are showing promising results and could be helping patients in the near future.

Crosstalk between brain, lung and heart in critical care

Extracerebral complications, especially pulmonary and cardiovascular, are frequent in brain-injured patients and are major outcome determinants. Two major pathways have been described: brain-lung and brain-heart interactions. Lung injuries after acute brain damages include ventilator-associated pneumonia (VAP), acute respiratory distress syndrome (ARDS) and neurogenic pulmonary œdema (NPE), whereas heart injuries can range from cardiac enzymes release, ECG abnormalities to left ventricle dysfunction or cardiogenic shock. The pathophysiologies of these brain-lung and brain-heart crosstalk are complex and sometimes interconnected. This review aims to describe the epidemiology and pathophysiology of lung and heart injuries in brain-injured patients with the different pathways implicated and the clinical implications for critical care physicians.

Causal Link between Ventricular Ectopy and Concussion

We present a unique case study report of a male individual with a history of mild nonischaemic cardiomyopathy, with no ventricular ectopy, that at the age of 76 years sustained multiple concussions (i.e., mild traumatic brain injury) within a week of each other. Concussion symptoms included cognitive difficulties, "not feeling well," lethargy, fatigue, and signs of depression. He was later medically diagnosed with postconcussion syndrome. The patient, WJT, was referred for cardiac and neurological assessment. Structural neuroimaging of the brain (MRI) was unremarkable, but electrocardiography (ECG) assessments using a 24-hour Holter monitor revealed significant incidence of ventricular ectopy (9.4%; 9,350/99,836 beats) over a period of 5-6 months after injury and then a further increase in ventricular ectopy to 18% (15,968/88,189 beats) during the subsequent 3 months. The patient was then prescribed Amiodarone 200 mg, and his ventricular ectopy and concussion symptoms completely resolved simultaneously within days. To the authors' knowledge, our study is the first to show a direct link between observable and documented cardiac dysregulation and concussion symptomology. Our study has important implications for both cardiac patients and the patients that sustain a concussion, and if medically managed with appropriate pharmacological intervention, it can reverse ventricular ectopy and concussion symptomology. More research is warranted to investigate the mechanisms for this dramatic and remarkable change in cardiac and cerebral functions and to further explore the brain-heart interaction and the intricate autonomic interaction that exists between the extrinsic and intracardiac nervous systems.

Troponin I as an early biomarker of cardiopulmonary parameters during the first 24 h of intensive care unit treatment in isolated traumatic brain injury patients

OBJECTIVE

Cardiopulmonary (CP) complications are well-known phenomena after an isolated traumatic brain injury (iTBI) and they may be associated with an elevated serum troponin I (TnI) value. However, the influence of an elevated TnI level on CP parameters within the first 24 h after an iTBI is still unknown. The current study was conducted to assess the associations between the initial TnI value on admission and CP parameters during the first 24 h of intensive care unit (ICU) treatment in iTBI patients.

PATIENTS AND METHODS

A total of 288 patients with iTBIs, who were admitted to our emergency department between January 2010 and November 2016 were retrospectively analyzed. Blood samples were taken on admission to determine TnI value. Each patient's demographic data, treatment regime, computed tomography results, and intra-hospital outcomes were evaluated, as well as several CP parameters, within the first 24 h of ICU treatment. The entire study population was stratified into patients with an initial TnI elevation (TnI positive) and without an initial TnI elevation (TnI negative).

RESULTS

Increased TnI values on admission were found in 59 (20.5%) patients. There were significant correlations between an initially elevated TnI value and a lower Glasgow Coma Scale score (p = 0.003), higher head Abbreviated Injury Scale score (p<0.0001), and higher Acute Physiology and Chronic Health Evaluation II score (p = 0.005) on admission, as well as a lower Glasgow Outcome Scale score (p = 0.0002) and higher modified Rankin Scale score (p = 0.0001) at discharge. In addition, a significantly higher norepinephrine application rate (NAR) (p<0.0001) and inspiratory oxygen fraction (FiO2) (p = 0.028) were needed in the TnI positive group.

CONCLUSION

Patients with elevated TnI values on admission require more circulation support (NAR and FiO2) within the first 24 h of ICU treatment after an iTBI. Therefore, the TnI may be a useful biomarker to improve ICU treatment of these patients.

Comparative analysis for the implication of serum cardiac troponin measurements by conventional versus high-sensitivity assays in patients with traumatic brain injury

BACKGROUND

Stress-induced myocardial injury is not well-studied in patients with head injury. We aimed to assess the prognostic implication of positive (+ve) Troponins (Tn) measurements by conventional (cTnT) versus High-Sensitivity (HsTnT) assay in patients with traumatic brain injury (TBI).

METHODS

A retrospective analysis was conducted for patients who were admitted with TBI. Patient demographics, clinical presentation, troponin assay results, TBI lesions, and hospital outcomes were analyzed and compared based on troponin assay (cTnT versus HsTnT).

RESULTS

Across the study period, 654 patients with TBI had troponin levels measured within 24 h postinjury (cTnT=252 and HsTnT=402). The mean age was 31 years and 46% had positive troponins. There were 147 deaths (22.5%); of them 54% had +ve HsTnT, 23% had +ve cTnT, 16% had -ve cTnT and 7% had -ve HsTnT). When the troponins were tested ≤4 h postinjury, the mortality was 10.2% in patients with -ve cTnT and 4% in patients with -ve HsTnT. There was no documented obvious direct trauma to the heart. Overall, patients with positive troponins had lower Glasgow Coma Scale (GCS), higher Injury Severity Scores and higher rates of brain edema (P=0.001), pneumonia and sepsis (P=0.001) than those with negative troponin results. In two different models, multivariate regression analysis showed that +ve cTnT and +ve HsTnT were independent predictors of mortality (OR 4.02, 95% CI: 1.72-9.39) and (OR 4.31; 95% CI: 1.76-10.57); respectively, after adjusting for age, injury severity scores, GCS at ED, head AIS, pneumonia, ARDS, surgical interventions, and chest injury.

CONCLUSIONS

Although the positivity of any troponin assay is associated with high mortality post-TBI, the use of HsTnT relatively outperforms the conventional troponin assay for early risk stratification and detection of stress-induced myocyte injury in patients with TBI.

Early cardiovascular function and associated hemodynamics in adults with isolated moderate-severe traumatic brain injury: A pilot study

BACKGROUND

While cardiac dysfunction has been described following traumatic brain injury (TBI), its association with systemic and cerebral hemodynamics is not known. We examined the contemporaneous relationship between early cardiac function with systemic and cerebral hemodynamic parameters after moderate-severe TBI.

METHODS

Bedside transthoracic echocardiography (TTE) and transcranial Doppler (TCD) ultrasonography were performed within 24 h in patients > 18 years with isolated moderate-severe TBI. Systemic hemodynamic parameters were quantified using routine monitoring [heart rate and mean arterial pressures (MAP)] and calculation from echocardiographic data [stroke volume index (SVI), cardiac index (CI), and systemic vascular resistance index (SVRI)]. Systolic dysfunction was defined using TTE as global longitudinal strain (GLS) > -16%. Mean middle cerebral artery velocity (FVm) was the measure of cerebral hemodynamics and quantified using TCD.

RESULTS

Among 15 patients [mean age 43 ± 13 years, GCS 5 ± 3, 73% male], 15 TTE and 15 TCD exams were performed simultaneously. Five (33%) patients had systolic dysfunction, with significantly worse GLS (median [IQR] -12.1% [-14.1, -12] vs. -19.1% [-19.9, -17.7], p = 0.004). Median (IQR) MAP was 97 (89, 107) mmHg, SVI (29.0 [20.5, 31.0] mL m^-2), and CI (2.83 [2.05, 3.10] L/min m^-2) were low to normal, while SVRI (2704 dyne sec/cm⁵ m^-2 [2210, 4084]) was normal to high. None of the patients had abnormal TCDs. Higher GLS (reduced systolic function) was associated with lower SVI (r² = 0.274, p = 0.03) but not other parameters.

CONCLUSION

Systemic hemodynamic parameters were consistent with an early catecholamine-excess state. While reduced systolic function was associated with lower SVI, there was no relationship with reduced cerebral perfusion, possibly due to normal MAP.

Elevated serum cardiac troponin and mortality in acute pulmonary embolism: Systematic review and meta-analysis

OBJECTIVES

To evaluate whether elevated levels of cardiac troponin increases the risk of mortality in patients with acute PE.

METHODS

We conducted a systematic review and meta-analysis with rigorous statistical evaluation using publications (2000-2018) from Cochrane Library, MEDLINE, PubMed, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), WHO International Clinical Trials Registry Platform, and Google Scholar databases. We searched for retrospective, prospective, and randomized controlled trials (RCT) or quasi-RCT studies that assessed the effect of elevated troponin versus normal levels on the outcomes of PE. The main outcome of interest was all-cause mortality. Extracted data included authors, the origin of studies, source population, study settings and duration, inclusion/exclusion criteria, data sources and measurement, sample size, and mortality. Data heterogeneity was assessed using the Cochrane Q homogeneity test with a significance set at p < 0.10. If the studies were statistically homogeneous, a fixed effect model was selected.

RESULTS

Out of 1825 references, 46 analytical studies were included with a total of 10842 patients with PE. The effect of elevated troponin on mortality had a pooled odd ratio (OR) of 4.33 for all studies, 3.7for HsTnT, 14.81 for HsTnI, 7.85 for cTnT, 2.81 for cTnI, 9.02 for low-risk PE and 4.80 for 90-day mortality. The pooled negative likelihood ratios for all-cause mortality using HsTnI, cTnI and cTnT assay were 0.21, 0.33 and 0.65, respectively.

CONCLUSION

Regardless of the troponin assay, pooled analysis indicates that elevated troponin is significantly associated with higher mortality in patients with PE.

Significance of Cardiac Troponin I Elevation in Traumatic Brain Injury Patients

Background

Myocardial dysfunction is frequently described as an underlying cause of mortality in traumatic brain injury (TBI) known as brain-cardiac link. However the impact on prognosis of a disease remains uncertain.

Objectives

The current study aimed at investigating the correlation between TBI and cardiac troponin I (cTnI) rise and in-hospital mortality rate among patients with TBI.

Methods

In the current prospective study TBI patients with abbreviated injury scale score (AIS) > 3 and Glasgow coma scale (GCS) score ≤ 8 with cTnI measurement within the first 24 hours of admission were evaluated. Chi-square, Kruskal-Wallis, Mann-Whitney U and Logistic Regression tests were used for data analysis.

Results

A total of 166 eligible patients were studied .The mean age of the cases was 37.64 ± 17.21 years, largely under 65 (93.4%) and male (86.7%).The most common injuries were cerebral contusion (35.1%), while motor vehicle crash (MVC) was the most common cause of injuries (83.73%); 59 % of the patients showed detectable cTnI concentrations within 24 hours of admission; 65.7% of the patients expired; they showed higher levels of cTnI compared to survivors that showed lower levels, 0.148 ± 0.074 vs 0.057 ± 0.055, respectively (P < 0.001). Moreover, a significant association was observed between mortality rate and lower admission GCS 3.49 ± 1.08 vs 6.79 ± 1.66, respectively (P < 0.001).

Conclusions

Increased cTnI levels could be a predictor of mortality among patients with TBI. Its measurement and investigation for therapeutic strategies could lead to better management of these cases.

Predictive value of positive high-sensitivity troponin T in intubated traumatic brain injury patients

OBJECTIVEThe clinical relevance of high-sensitivity troponin T (HsTnT) in trauma patients is not well explored. In this study, the authors aimed to study the predictive value of serum HsTnT in intubated patients who had sustained traumatic brain injury (TBI).METHODSA retrospective analysis was conducted for all intubated TBI patients between 2010 and 2014 at a national level 1 trauma center. Data were analyzed and compared based on the HsTnT status on admission (group 1, negative results; and group 2, positive results). Receiver operating characteristic curves were used to determine sensitivity, specificity, and cutoff level of HsTnT to predict mortality. Time to earlier discharge from hospital or death was modeled using Cox proportional hazard models to describe the relationship between HsTnT and in-hospital mortality.RESULTSOf the 826 intubated TBI patients, 490 underwent HsTnT testing; 65.7% had positive HsTnT results. Patients in group 2 had a higher Injury Severity Score (p = 0.001) and head Abbreviated Injury Scale (AIS) score (p = 0.004) than those in group 1. In addition, group 2 patients were more likely to have lower Glasgow Coma Scale scores (p = 0.001) and more likely to experience intraventricular hemorrhage, brain edema, pneumonia, and sepsis (p = 0.001). HsTnT values positively correlated with head AIS score (r = 0.19, p = 0.001) and varied by the type of lesion and time to death. Ventilator days and length of hospital stay were more prolonged in group 2 patients (p = 0.001). Area under the curve (AUC) analysis showed that HsTnT ≥ 26.5 ng/L predicted all-cause mortality (AUC 0.75, 95% CI 0.699-0.801) with 80% sensitivity. Positive HsTnT was an independent predictor of mortality in multivariate models (adjusted OR 3.10, 95% CI 1.308-7.351) even after excluding chest injury (adjusted OR 4.18, 95% CI 1.320-13.231).CONCLUSIONSPositive HsTnT results are associated with poor outcomes in intubated patients with TBI. In this subset of patients, measuring serum HsTnT on admission is a useful tool for early risk stratification and expedited care; however, further prospective studies are warranted.

Serum cardiac troponins as prognostic markers in patients with traumatic and non-traumatic brain injuries: A meta-analysis

OBJECTIVE

The association between brain injury and elevated serum cardiac troponin (cTn) remains poorly understood. We conducted a systematic review and meta-analysis to evaluate whether elevated cTn increases the risk of mortality in patients with traumatic (TBI) or non-traumatic brain injury (NT-BI).

METHODS

Cochrane Library, MEDLINE, PubMed, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), WHO International Clinical Trials Registry Platform, and Google scholar databases, and clinicaltrials.gov were searched for a retrospective, prospective and randomized clinical trials (RCT) or quasi-RCT studies that assessed the effect of elevated cTn (conventional or high sensitive assay) on the outcomes of brain injury patients. The main outcome of interest was mortality. Two authors independently abstracted the data using a data collection form. Results from different studies were pooled for analysis, whenever appropriate. The total number of patients pooled was 2435, of which 916 had elevated cTn and 1519 were in control group.

RESULTS

Out of 691 references identified through the search, 8 analytical studies met inclusion criteria. Among both types of brain injuries, an elevated cTn was associated with a higher mortality with an overall pooled odd ratio (OR) of 3.37 (95% CI 2.13-5.36). The pooled OR for mortality was 3.31 (95% CI 1.99-5.53) among patients with TBI and 3.36 (95% CI 1.32-8.6) among patients with NT-BI.

CONCLUSIONS

Pooled analysis indicates that elevated cTn is significantly associated with a high mortality in patients with TBI and NT-BI. Prospective clinical trials are needed to support these findings and to inform a biomarker risk stratification regardless of the mechanism of injury.