Ability of Fibrin Monomers to Predict Progressive Hemorrhagic Injury in Patients with Severe Traumatic Brain Injury

ABO blood type and functional neurological outcome in patients with severe traumatic brain injury

BACKGROUND

The ABO blood system has been involved in the pathogenesis of several diseases, including coagulopathy and bleeding complications. In trauma patients, blood type A has been associated with acute respiratory distress syndrome, and recently, blood type O has been associated with all-cause mortality. The purpose of this study was to assess the association between ABO blood types and long-term functional outcomes in critically ill patients with severe traumatic brain injury (TBI).

METHODS

We conducted a single-center, retrospective, observational study including all patients admitted to the intensive care unit with severe TBI (defined as a Glasgow Coma Scale score of ≤8) between January 2007 and December 2018. Patient characteristics and outcomes were extracted from a prospective registry of all intubated patients admitted to the intensive care unit for TBI. ABO blood types were retrospectively retrieved from patient medical records. The association between ABO blood type (A, B, AB, and O) and unfavorable functional outcome (defined by a Glasgow Outcome Scale score between 1 and 3) 6 months after injury was assessed in univariate and multivariate analysis.

RESULTS

A total of 333 patients meeting the inclusion criteria were included. There were 151 type O (46%), 131 type A (39%), 37 type B (11%), and 12 type AB patients (4%). No significant differences in baseline demographic, clinical, or biological characteristics were observed between blood types. The prevalence of unfavorable outcome was significantly different between the four groups. After adjustment for confounders, blood type O was significantly associated with unfavorable outcome at 6 months (odds ratio, 1.97; confidence interval [1.03-3.80]; p = 0.042). The prevalence of coagulopathy or progressive hemorrhagic injury was not statistically different between blood types ( p = 0.575 and p = 0.813, respectively).

CONCLUSION

Blood type O appears to be associated with unfavorable long-term functional outcome in critically ill patients with severe TBI. Further studies are needed to detail the mechanism underlying this relationship.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level IV.

Severe trauma patients requiring undelayable combined cranial and extracranial surgery: A scoping review of an emerging concept

Objectives

Although patients suffering from severe traumatic brain injury (sTBI) and severe trauma patients (STP) have been extensively studied separately, there is scarce evidence concerning STP with concomitant sTBI. In particular, there are no guidelines regarding the emergency surgical management of patients presenting a concomitant life-threatening intracranial hematoma (ICH) and a life-threatening non-compressible extra-cranial hemorrhage (NCEH).

Materials and Methods

A scoping review was conducted on Medline database from inception to September 2021.

Results

The review yielded 138 articles among which 10 were retained in the quantitative analysis for a total of 2086 patients. Seven hundrer and eighty-seven patients presented concomitant sTBI and extra-cranial severe injuries. The mean age was 38.2 years-old and the male to female sex ratio was 2.8/1. Regarding the patients with concomitant cranial and extra-cranial injuries, the mean ISS was 32.1, and the mean AIS per organ were 4.0 for the head, 3.3 for the thorax, 2.9 for the abdomen and 2.7 for extremity. This review highlighted the following concepts: emergency peripheric osteosynthesis can be safely performed in patients with concomitant sTBI (grade C). Invasive intracranial pressure monitoring is mandatory during extra-cranial surgery in patients with sTBI (grade C). The outcome of STP with concomitant sTBI mainly depends on the seriousness of sTBI, independently from the presence of extra-cranial injuries (grade C). After exclusion of early-hospital mortality, the impact of extra-cranial injuries on mortality in patients with concomitant sTBI is uncertain (grade C). There are no recommendations regarding the combined surgical management of patients with concomitant ICH and NCEH (grade D).

Conclusion

This review revealed the lack of evidence for the emergency surgical management of patients with concomitant ICH and NCEH. Hence, we introduce the concept of combined cranial and extra-cranial surgery. This damage-control surgical strategy aims to reduce the time spent with intracranial hypertension and to hasten the admission in the intensive care unit. Further studies are required to validate this concept in clinical practice.

PEGylated Polyester Nanoparticles Trigger Adverse Events in a Large Animal Model of Trauma and in Naı̈ve Animals: Understanding Cytokine and Cellular Correlations with These Events

Intravenously infusible nanoparticles to control bleeding have shown promise in rodents, but translation into preclinical models has been challenging as many of these nanoparticle approaches have resulted in infusion responses and adverse outcomes in large animal trauma models. We developed a hemostatic nanoparticle technology that was screened to avoid one component of the infusion response: complement activation. We administered these hemostatic nanoparticles, control nanoparticles, or saline volume controls in a porcine polytrauma model. While the hemostatic nanoparticles promoted clotting as marked by a decrease in prothrombin time and both the hemostatic nanoparticles and controls did not active complement, in a subset of the animals, hard thrombi were found in uninjured tissues in both the hemostatic and control nanoparticle groups. Using data science methods that allow one to work across heterogeneous data sets, we found that the presence of these thrombi correlated with changes in IL-6, INF-alpha, lymphocytes, and neutrophils. While these findings might suggest that this formulation would not be a safe one for translation for trauma, they provide guidance for developing screening tools to make nanoparticle formulations in the complex milieux of trauma as well as for therapeutic interventions more broadly. This is important as we look to translate intravenously administered nanoparticle formulations for therapies, particularly considering the vascular changes seen in a subset of patients following COVID-19. We need to understand adverse events like thrombi more completely and screen for these events early to make nanomaterials as safe and effective as possible.

Radiomics Features on Computed Tomography Combined With Clinical-Radiological Factors Predicting Progressive Hemorrhage of Cerebral Contusion

Background

Traumatic brain injury (TBI) is the main cause of death and severe disability in young adults worldwide. Progressive hemorrhage (PH) worsens the disease and can cause a poor neurological prognosis. Radiomics analysis has been used for hematoma expansion of hypertensive intracerebral hemorrhage. This study attempts to develop an optimal radiomics model based on non-contrast CT to predict PH by machine learning (ML) methods and compare its prediction performance with clinical-radiological models.

Methods

We retrospectively analyzed 165 TBI patients, including 89 patients with PH and 76 patients without PH, whose data were randomized into a training set and a testing set at a ratio of 7:3. A total of 10 different machine learning methods were used to predict PH. Univariate and multivariable logistic regression analyses were implemented to screen clinical-radiological factors and to establish a clinical-radiological model. Then, a combined model combining clinical-radiological factors with the radiomics score was constructed. The area under the receiver operating characteristic curve (AUC), accuracy and F1 score, sensitivity, and specificity were used to evaluate the models.

Results

Among the 10 various ML algorithms, the support vector machine (SVM) had the best prediction performance based on 12 radiomics features, including the AUC (training set: 0.918; testing set: 0.879) and accuracy (training set: 0.872; test set: 0.834). Among the clinical and radiological factors, the onset-to-baseline CT time, the scalp hematoma, and fibrinogen were associated with PH. The radiomics model's prediction performance was better than the clinical-radiological model, while the predictive nomogram combining the radiomics features with clinical-radiological characteristics performed best.

Conclusions

The radiomics model outperformed the traditional clinical-radiological model in predicting PH. The nomogram model of the combined radiomics features and clinical-radiological factors is a helpful tool for PH.

Extended Coagulation Profiling in Isolated Traumatic Brain Injury: A CENTER-TBI Analysis

BACKGROUND

Trauma-induced coagulopathy in traumatic brain injury (TBI) remains associated with high rates of complications, unfavorable outcomes, and mortality. The underlying mechanisms are largely unknown. Embedded in the prospective multinational Collaborative European Neurotrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study, coagulation profiles beyond standard conventional coagulation assays were assessed in patients with isolated TBI within the very early hours of injury.

METHODS

Results from blood samples (citrate/EDTA) obtained on hospital admission were matched with clinical and routine laboratory data of patients with TBI captured in the CENTER-TBI central database. To minimize confounding factors, patients with strictly isolated TBI (iTBI) (n = 88) were selected and stratified for coagulopathy by routine international normalized ratio (INR): (1) INR < 1.2 and (2) INR ≥ 1.2. An INR > 1.2 has been well adopted over time as a threshold to define trauma-related coagulopathy in general trauma populations. The following parameters were evaluated: quick's value, activated partial thromboplastin time, fibrinogen, thrombin time, antithrombin, coagulation factor activity of factors V, VIII, IX, and XIII, protein C and S, plasminogen, D-dimer, fibrinolysis-regulating parameters (thrombin activatable fibrinolysis inhibitor, plasminogen activator inhibitor 1, antiplasmin), thrombin generation, and fibrin monomers.

RESULTS

Patients with iTBI with INR ≥ 1.2 (n = 16) had a high incidence of progressive intracranial hemorrhage associated with increased mortality and unfavorable outcome compared with patients with INR < 1.2 (n = 72). Activity of coagulation factors V, VIII, IX, and XIII dropped on average by 15-20% between the groups whereas protein C and S levels dropped by 20%. With an elevated INR, thrombin generation decreased, as reflected by lower peak height and endogenous thrombin potential (ETP), whereas the amount of fibrin monomers increased. Plasminogen activity significantly decreased from 89% in patients with INR < 1.2 to 76% in patients with INR ≥ 1.2. Moreover, D-dimer levels significantly increased from a mean of 943 mg/L in patients with INR < 1.2 to 1,301 mg/L in patients with INR ≥ 1.2.

CONCLUSIONS

This more in-depth analysis beyond routine conventional coagulation assays suggests a counterbalanced regulation of coagulation and fibrinolysis in patients with iTBI with hemostatic abnormalities. We observed distinct patterns involving key pathways of the highly complex and dynamic coagulation system that offer windows of opportunity for further research. Whether the changes observed on factor levels may be relevant and explain the worse outcome or the more severe brain injuries by themselves remains speculative.

Association between serum calcium level and hemorrhagic progression in patients with traumatic intraparenchymal hemorrhage: Investigating the mediation and interaction effects of coagulopathy

In this study, we investigate the association of serum calcium with coagulopathy and hemorrhagic progression contusion (HPC) in patients with traumatic intraparenchymal hemorrhage (tIPH), and further explored the interaction and mediation effect between serum calcium as well as coagulopathy on HPC. Retrospective analyses of patients with tIPH admitted to the First Affiliated Hospital of Wenzhou Medical University between January 2016 to December 2019. The clinical data, coagulation parameters, and serum calcium levels were collected for further analysis. Multivariate logistic regression analysis was applied to identify the association of serum calcium level with coagulopathy and HPC. Causal mediation analysis (CMA) and additive interaction model were used to estimate the interaction and mediation effect between serum calcium as well as coagulopathy on HPC. Additionally, we repeated the analysis using corrected calcium. A total of 473 patients were included in this study. Of these, 54 (11.4%) patients had hypocalcemia at admission, 105 (22.2%) presented with coagulopathy, and 187 (39.5%) experienced HPC. Admission serum calcium level in patients presented with coagulopathy and HPC were 8.84 [IQR: 8.44-9.40] and 8.92 [IQR: 8.48-9.40] mg/dL respectively, which were significantly lower than that of patients without (9.10 [IQR: 8.68-9.88] and 9.12 [IQR: 8.72-9.89] mg/dL; all p < 0.001). Multivariate logistic regression analysis identified that hypocalcemia emerged as an independent risk factor for coagulopathy and HPC. However, no significant interaction was detected between hypocalcemia and coagulopathy. CMA showed that the mediator coagulopathy explained 24.4% (95% CI: 4.7-65.0%; p = 0.006) of the association between hypocalcemia and HPC. Moreover, comparable results were held using corrected calcium as well. Admission serum calcium level is associated with the HPC for patients with tIPH and this relationship is partially mediated by coagulopathy, but no significant interaction is detected. Further studies are needed to validate the findings and explore its mechanisms.

Severe Trauma Patients Requiring Undelayable Combined Cranial and Extra-Cranial Surgery: A Proof-of-Concept Monocentric Study

INTRODUCTION

To date, there is no evidence concerning the emergency surgical management of severe trauma patients (STP) with severe traumatic brain injury (STBI) presenting a life-threatening intracranial hematoma and a concomitant extra-cranial noncompressible active bleeding. Current guidelines recommend stopping the extra-cranial bleeding first. Nevertheless, the long-term outcome of STP with STBI mainly depends from intracranial lesions. Thus, we propose a combined damage-control surgical strategy aiming to reduce the time spent with intracranial hypertension and to hasten the admission in the intensive care unit. The main objective of the study is to evaluate the benefits of combined cranial and extra-cranial surgery of STP on the long-term outcome.

MATERIALS AND METHODS

We retrospectively searched through the database of STBI of a level 1 trauma center facility (Sainte-Anne Military Teaching Hospital, Toulon, France) from 2007 until 2021 looking for patients who benefited from combined cranial and extra-cranial surgery in an acute setting.

RESULTS

The research yielded 8 patients. The mean age was 35 years old (±14) and the male to female sex ratio was 1.7/1. The trauma mechanism was a fall in 50% of the cases and a traffic accident in 50% of the cases. The median Glasgow coma scale score was 8 (IQR 4) before intubation. The median Injury Severity Score was 41 (IQR 16). Seven patients (88%) presented hypovolemic shock upon admission. Six patients (75%) benefited from damage-control laparotomy among, whom 4 (67%) underwent hemostatic splenectomy. One patient benefited from drainage of tension pneumothorax, and one patient benefited from external fixator of multiple limb fractures. Seven patients (88%) benefited from decompressive craniectomy for acute subdural hematoma (5 patients) or major brain contusion (2 patients). One patient (12%) benefited from craniotomy for epidural hematoma. Three patients presented intraoperative profound hypovolemic shock. Six patients (75%) presented a favorable neurologic outcome with minor complications from extra-cranial surgeries and 2 patients died (25%).

CONCLUSION

Performing combined life-saving cranial and extra-cranial surgery is feasible and safe as long as the trauma teams are trained according to the principles of damage control. It may be beneficial for the neurologic prognostic of STP with STBI requiring cranial and extra-cranial surgery.

Pathophysiology of Coagulopathy Induced by Traumatic Brain Injury Is Identical to That of Disseminated Intravascular Coagulation With Hyperfibrinolysis

Background: Traumatic brain injury (TBI)-associated coagulopathy is a widely recognized risk factor for secondary brain damage and contributes to poor clinical outcomes. Various theories, including disseminated intravascular coagulation (DIC), have been proposed regarding its pathomechanisms; no consensus has been reached thus far. This study aimed to elucidate the pathophysiology of TBI-induced coagulopathy by comparing coagulofibrinolytic changes in isolated TBI (iTBI) to those in non-TBI, to determine the associated factors, and identify the clinical significance of DIC diagnosis in patients with iTBI.

Methods: This secondary multicenter, prospective study assessed patients with severe trauma. iTBI was defined as Abbreviated Injury Scale (AIS) scores ≥4 in the head and neck, and ≤2 in other body parts. Non-TBI was defined as AIS scores ≥4 in single body parts other than the head and neck, and the absence of AIS scores ≥3 in any other trauma-affected parts. Specific biomarkers for thrombin and plasmin generation, anticoagulation, and fibrinolysis inhibition were measured at the presentation to the emergency department (0 h) and 3 h after arrival.

Results: We analyzed 34 iTBI and 40 non-TBI patients. Baseline characteristics, transfusion requirements and in-hospital mortality did not significantly differ between groups. The changes in coagulation/fibrinolysis-related biomarkers were similar. Lactate levels in the iTBI group positively correlated with DIC scores (rho = −0.441, p = 0.017), but not with blood pressure (rho = −0.098, p = 0.614). Multiple logistic regression analyses revealed that the injury severity score was an independent predictor of DIC development in patients with iTBI (odds ratio = 1.237, p = 0.018). Patients with iTBI were further subdivided into two groups: DIC (n = 15) and non-DIC (n = 19) groups. Marked thrombin and plasmin generation were observed in all patients with iTBI, especially those with DIC. Patients with iTBI and DIC had higher requirements for massive transfusion and emergency surgery, and higher in-hospital mortality than those without DIC. Furthermore, DIC development significantly correlated with poor hospital survival; DIC scores at 0 h were predictive of in-hospital mortality.

Conclusions: Coagulofibrinolytic changes in iTBI and non-TBI patients were identical, and consistent with the pathophysiology of DIC. DIC diagnosis in the early phase of TBI is key in predicting the outcomes of severe TBI.