Early Coagulopathy After Traumatic Brain Injury: The Role of Hypoperfusion and the Protein C Pathway

Role of the admission muscle injury indicators in early coagulopathy, inflammation and acute kidney injury in patients with severe multiple injuries

BACKGROUNDS

Coagulopathy, inflammation and organ failure are common complications in trauma patients. This study aimed to explore the possible role of muscle injury indicators in early coagulopathy, systemic inflammatory response syndrome (SIRS), and acute kidney injury (AKI) in patients with severe multiple trauma.

METHODS

A retrospective analysis was performed using trauma center patient data from 2020 to 2023. The incidence of coagulopathy, SIRS and AKI in patients with multiple injuries were assessed. The relationship between Myoglobin, creatine kinase (CK), lactate dehydrogenase (LDH) and trauma severity was investigated, and the influence of these three muscle injury indicators on patient adverse outcomes was analyzed.

RESULTS

A total of 312 patients with severe multiple injuries were included in this study, with an average age of 51.7 and a median Injury Severity Score (ISS) of 22.5. Among them, 115 patients developed coagulopathy, 169 patients developed SIRS, 26 patients developed AKI, and 11 patients died during hospitalization. We found that Myoglobin (r = 0.225, P < 0.001), CK (r = 0.204, P < 0.001), LDH (r = 0.175, P = 0.002) were positively correlated with ISS. Myoglobin is an independent risk factor for coagulopathy (OR = 1.90, 95%CI: 1.45-2.49), SIRS (OR = 1.41, 95%CI: 1.10-1.79), and AKI (OR = 4.17, 95%CI: 2.19-7.95). CK is an independent risk factor for coagulopathy (OR = 1.30, 95%CI: 1.00-1.67), while LDH is an independent risk factor for SIRS (OR = 1.49, 95%CI: 1.17-1.89) and AKI (OR = 2.30, 95%CI: 1.43-3.69). Especially for AKI, Myoglobin had a good predictive effect (AUC = 0.804, 95%CI:0.716-0.891). The best cut-off value is when the Myoglobin value is 931.11 µg/L, at which point the sensitivity is 61.53% and the specificity is 87.41%.

CONCLUSIONS

The admission muscle injury index can predict trauma complications such as AKI, early coagulation disease, and SIRS, especially AKI. Compared to CK and LDH, admission myoglobin can predict complications remarkably, even better than ISS, especially AKI. Routine testing of muscle injury indicators upon admission is meaningful and can help physicians identify and prevent the occurrence of complications.

Coagulopathy at admission in traumatic brain injury and its association with hematoma progression: A systematic review and meta-analysis of 2411 patients

Progressive hemorrhagic injury (PHI) is a frequent complication of traumatic brain injury (TBI). This study aims to investigate the impact of coagulation factors (platelet [PLT], prothrombin time [PT], activated partial thromboplastin time [aPTT], international normalized ratio 1, fibrinogen [Fg], D-dimer [Dd], and fibrin [Fib]) at admission and PHI development through a comprehensive systematic review and meta-analysis based on PRISMA 2020 guideline. Databases including PubMed, Scopus, Web of Science, and Embase were searched up to March 2024. Controlled observational studies examining the relationship between coagulation tests at admission and PHI in isolated TBI cases were included. Risk of bias was assessed using the Joanna Briggs Institute (JBI) checklist, and statistical analyses were performed using Stata software, employing Hedge's g to measure effect sizes. Sixteen studies encompassing 2411 TBI patients were included. Significant associations were found between decreased PLT (g = -0.243, P = 0.007), increased aPTT (g = 0.117, P = 0.037), increased INR (g = 0.217, P = 0.0202), elevated Dd levels (g = 1.57, P = 0.0084), and decreased Fg levels (g = -0.26, P = 0.0001) with the risk of developing PHI. PT showed no significant effect on PHI risk (g = 0.19, P = 0.0372). Our results suggest that elevated INR, Dd levels, and aPTT are linked to an increased risk of PHI. Conversely, higher PLT and Fg levels appear to be associated with a reduced PHI risk. Notably, Dd demonstrated stronger predictive power for PHI.

Neurodegenerative Disorders in the Context of Vascular Changes after Traumatic Brain Injury

Traumatic brain injury (TBI) results from external biomechanical forces that cause structural and physiological disturbances in the brain, leading to neuronal, axonal, and vascular damage. TBIs are predominantly mild (65%), with moderate (10%) and severe (25%) cases also prevalent. TBI significantly impacts health, increasing the risk of neurodegenerative diseases such as dementia, post injury. The initial phase of TBI involves acute disruption of the blood–brain barrier (BBB) due to vascular shear stress, leading to ischemic damage and amyloid-beta accumulation. Among the acute cerebrovascular changes after trauma are early progressive hemorrhage, micro bleeding, coagulopathy, neurovascular unit (NVU) uncoupling, changes in the BBB, changes in cerebral blood flow (CBF), and cerebral edema. The secondary phase is characterized by metabolic dysregulation and inflammation, mediated by oxidative stress and reactive oxygen species (ROS), which contribute to further neurodegeneration. The cerebrovascular changes and neuroinflammation include excitotoxicity from elevated extracellular glutamate levels, coagulopathy, NVU, immune responses, and chronic vascular changes after TBI result in neurodegeneration. Severe TBI often leads to dysfunction in organs outside the brain, which can significantly impact patient care and outcomes. The vascular component of systemic inflammation after TBI includes immune dysregulation, hemodynamic dysfunction, coagulopathy, respiratory failure, and acute kidney injury. There are differences in how men and women acquire traumatic brain injuries, how their brains respond to these injuries at the cellular and molecular levels, and in their brain repair and recovery processes. Also, the patterns of cerebrovascular dysfunction and stroke vulnerability after TBI are different in males and females based on animal studies.

Risk factors for thromboembolic complications in isolated severe head injury

PURPOSE

Patients with traumatic brain injury (TBI) are at high risk for venous thromboembolism (VTE). The aim of the present study is to identify factors independently associated with VTE events. Specifically, we hypothesized that the mechanism of penetrating head trauma might be an independent factor associated with increased VTE events when compared with blunt head trauma.

METHODS

The ACS-TQIP database (2013-2019) was queried for all patients with isolated severe head injuries (AIS 3-5) who received VTE prophylaxis with either unfractionated heparin or low-molecular-weight heparin. Transfers, patients who died within 72 h and those with a hospital length of stay < 48 h were excluded. Multivariable analysis was used as the primary analysis to identify independent risk factors for VTE in isolated severe TBI.

RESULTS

A total of 75,570 patients were included in the study, 71,593 (94.7%) with blunt and 3977 (5.3%) with penetrating isolated TBI. Penetrating trauma mechanism (OR 1.49, CI 95% 1.26-1.77), increasing age (age 16-45: reference; age > 45-65: OR 1.65, CI 95% 1.48-1.85; age > 65-75: OR 1.71, CI 95% 1.45-2.02; age > 75: OR 1.73, CI 95% 1.44-2.07), male gender (OR 1.53, CI 95% 1.36-1.72), obesity (OR 1.35, CI 95% 1.22-1.51), tachycardia (OR 1.31, CI 95% 1.13-1.51), increasing head AIS (AIS 3: reference; AIS 4: OR 1.52, CI 95% 1.35-1.72; AIS 5: OR 1.76, CI 95% 1.54-2.01), associated moderate injuries (AIS = 2) of the abdomen (OR 1.31, CI 95% 1.04-1.66), spine (OR 1.35, CI 95% 1.19-1.53), upper extremity (OR 1.16, CI 95% 1.02-1.31), lower extremity (OR 1.46, CI 95% 1.26-1.68), craniectomy/craniotomy or ICP monitoring (OR 2.96, CI 95% 2.65-3.31) and pre-existing hypertension (OR 1.18, CI 95% 1.05-1.32) were identified as independent risk factors for VTE complications in isolated severe head injury. Increasing GCS (OR 0.93, CI 95% 0.92-0.94), early VTE prophylaxis (OR 0.48, CI 95% 0.39-0.60) and LMWH compared to heparin (OR 0.74, CI 95% 0.68-0.82) were identified as protective factors for VTE complications.

CONCLUSION

The identified factors independently associated with VTE events in isolated severe TBI need to be considered in VTE prevention measures. In penetrating TBI, an even more aggressive VTE prophylaxis management may be justified as compared to that in blunt.

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.

Dynamics of neutrophil-to-lymphocyte ratio can be associated with clinical outcomes of children with moderate to severe traumatic brain injury: A retrospective observational study

BACKGROUND

The neutrophil to lymphocyte ratio (NLR) has been reported to be associated with clinical outcomes of patients with severe traumatic brain injury (TBI). This study aimed to evaluate the correlation between the dynamics of NLR and clinical outcomes of pediatric patients with moderate to severe TBI.

METHODS

We retrospectively evaluated the clinical data of a total of 374 pediatric patients with moder-ate to severe TBI who were treated in our department between May 2016 and May 2020. Clinical and laboratory data including the NLR upon admission and the NLR on hospital day four were collected. Poor clinical outcome was defined as Glasgow Outcome Scale (GOS) of 1-3. Multivariable logistic regression analyses were performed to investigate the correlation between the dynamics of NLR and clinical outcome.

RESULTS

Three hundred seventy-four pediatric patients (mean age 7.37 ± 3.11, 52.7% male) were evaluated. Based on the ROC curves, a value of 5 was determined as the NLR cut-off value. The corresponding cutoff value for delta NLR was 1. The Glasgow Coma Scale (GCS) (OR, 3.42; 95% CI: 1.88-5.28; P <0.001), the light reflex (OR, 1.79; 95% CI: 1.34- 2.84; P = 0.027), the Rotterdam CT score (OR, 2.71; 95% CI: 1.72-4.13; P = 0.021), and delta NLR (OR, 1.71; 95% CI: 1.13- 2.52; P = 0.034) were identified as independent predictors for unfavorable outcomes in multivariable logistic regression analysis.

CONCLUSIONS

The result of the present study suggest that delta NLR could be a predictor of poor clinical outcome of pediatrics with moderate to severe TBI. This cost-effective and easily available biomarker could be used to predict clinical outcomes in these patients.

Credibility of the Neutrophil-to-Lymphocyte Count Ratio in Severe Traumatic Brain Injury

Traumatic brain injury (TBI) is one of the leading causes of morbidity and mortality worldwide. The consequences of a TBI generate the activation and accumulation of inflammatory cells. The peak number of neutrophils entering into an injured brain is observed after 24 h; however, cells infiltrate within 5 min of closed brain injury. Neutrophils release toxic molecules including free radicals, proinflammatory cytokines, and proteases that advance secondary damage. Regulatory T cells impair T cell infiltration into the central nervous system and elevate reactive astrogliosis and interferon-γ gene expression, probably inducing the process of healing. Therefore, the neutrophil-to-lymphocyte ratio (NLR) may be a low-cost, objective, and available predictor of inflammation as well as a marker of secondary injury associated with neutrophil activation. Recent studies have documented that an NLR value on admission might be effective for predicting outcome and mortality in severe brain injury patients.

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.

Relationship between admission coagulopathy and prognosis in children with traumatic brain injury: a retrospective study

BACKGROUND

Coagulopathy in adult patients with traumatic brain injury (TBI) is strongly associated with unfavorable outcomes. However, few reports focus on pediatric TBI-associated coagulopathy.

METHODS

We retrospectively identified children with Glasgow Coma Scale ≤ 13 in a tertiary pediatric hospital from April 2012 to December 2019 to evaluate the impact of admission coagulopathy on their prognosis. A classification and regression tree (CART) analysis using coagulation parameters was performed to stratify the death risk among patients. The importance of these parameters was examined by multivariate logistic regression analysis.

RESULTS

A total of 281 children with moderate to severe TBI were enrolled. A receiver operating characteristic curve showed that activated partial thromboplastin time (APTT) and fibrinogen were effective predictors of in-hospital mortality. According to the CART analysis, APTT of 39.2 s was identified as the best discriminator, while 120 mg/dL fibrinogen was the second split in the subgroup of APTT ≤ 39.2 s. Patients were stratified into three groups, in which mortality was as follows: 4.5 % (APTT ≤ 39.2 s, fibrinogen > 120 mg/dL), 20.5 % (APTT ≤ 39.2 s and fibrinogen ≤ 120 mg/dL) and 60.8 % (APTT > 39.2 s). Furthermore, length-of-stay in the ICU and duration of mechanical ventilation were significantly prolonged in patients with deteriorated APTT or fibrinogen values. Multiple logistic regression analysis showed that APTT > 39.2 s and fibrinogen ≤ 120 mg/dL was independently associated with mortality in children with moderate to severe TBI.

CONCLUSIONS

We concluded that admission APTT > 39.2 s and fibrinogen ≤ 120 mg/dL were independently associated with mortality in children with moderate to severe TBI. Early identification and intervention of abnormal APTT and fibrinogen in pediatric TBI patients may be beneficial to their prognosis.

Trauma-induced coagulopathy

Uncontrolled haemorrhage is a major preventable cause of death in patients with traumatic injury. Trauma-induced coagulopathy (TIC) describes abnormal coagulation processes that are attributable to trauma. In the early hours of TIC development, hypocoagulability is typically present, resulting in bleeding, whereas later TIC is characterized by a hypercoagulable state associated with venous thromboembolism and multiple organ failure. Several pathophysiological mechanisms underlie TIC; tissue injury and shock synergistically provoke endothelial, immune system, platelet and clotting activation, which are accentuated by the 'lethal triad' (coagulopathy, hypothermia and acidosis). Traumatic brain injury also has a distinct role in TIC. Haemostatic abnormalities include fibrinogen depletion, inadequate thrombin generation, impaired platelet function and dysregulated fibrinolysis. Laboratory diagnosis is based on coagulation abnormalities detected by conventional or viscoelastic haemostatic assays; however, it does not always match the clinical condition. Management priorities are stopping blood loss and reversing shock by restoring circulating blood volume, to prevent or reduce the risk of worsening TIC. Various blood products can be used in resuscitation; however, there is no international agreement on the optimal composition of transfusion components. Tranexamic acid is used in pre-hospital settings selectively in the USA and more widely in Europe and other locations. Survivors of TIC experience high rates of morbidity, which affects short-term and long-term quality of life and functional outcome.

Fibrinolytic Activation in Patients with Progressive Intracranial Hemorrhage after Traumatic Brain Injury

Progression of intracranial hemorrhage (PICH) is a significant cause of secondary brain injury in patients with traumatic brain injury (TBI). Previous studies have implicated a variety of mediators that contribute to PICH. We hypothesized that patients with PICH would display either a hypocoagulable state, hyperfibrinolysis, or both. We conducted a prospective study of adult trauma patients with isolated TBI. Blood was obtained for routine coagulation assays, platelet count, fibrinogen, thrombelastography, markers of thrombin generation, and markers of fibrinolysis at admission and 6, 12, 24, and 48 h. Univariate analyses were performed to compare baseline characteristics between groups. Linear regression models were created, adjusting for baseline differences, to determine the relationship between individual assays and PICH. One hundred forty-one patients met entry criteria, of whom 71 had hemorrhage progression. Patients with PICH had a higher Injury Severity Score and Abbreviated Injury Scale score (head), a lower Glasgow Coma Scale score, and lower plasma sodium on admission. Patients with PICH had higher D-dimers on admission. After adjusting for baseline differences, elevated D-dimers remained significantly associated with PICH compared to patients without PICH at admission. Hypocoagulation was not significantly associated with PICH in these patients. The association between PICH and elevated D-dimers early after injury suggests that fibrinolytic activation may contribute to PICH in patients with TBI.

A Selection of Trauma Scores Might Not Correlate with Coagulation Factor Activity following Multiple Injuries: A Retrospective Observational Study from a Level 1 Trauma Center

Loss and dilution of coagulation factors have been observed following multiple trauma. Timely recognition of reduced clotting factor activity might facilitate therapeutic action to restore normal coagulation function. This study investigates the potential role of some well-known trauma scores in predicting coagulation factor activity after multiple injuries. A dataset comprising the coagulation factor activities of 68 multiply injured adult patients was analyzed. The following trauma scores were evaluated: AIS, ISS, NISS, GCS, RTS, TRISS, RISC, and TASH score. To investigate the effect of trauma severity with respect to a single anatomic injury location, two groups according to the AIS (<3 vs. ≥3 points) were formed. Differences between these two groups were analyzed for five different body regions (head, thorax, abdomen, pelvis, extremities) using the Mann–Whitney U-test. Spearman's rank correlation coefficient rho was calculated to reveal possible relationships between trauma scores and clotting factor activities. The analysis showed clearly reduced clotting factor activities with a significant reduction of FII (83 vs. 50%; P = .021) and FV (83 vs. 46%; P = .008) for relevant (AIS ≥ 3 points) pelvic injuries. In contrast, traumatic brain injury according to the AIS head or the GCS does not appear to lead to a significant decrease in coagulation factor activities. Furthermore, the other scores studied show at best a fair correlation with coagulation factor activity. In this context, the RTS score seems to be the most suitable. Additionally, the predictive value of the TASH score, which was specifically developed to predict the need for mass transfusion, was also limited in this study. We would like to explicitly point out that this is not a criticism of the trauma scores, since they were developed in a completely different context.

Global Characterisation of Coagulopathy in Isolated Traumatic Brain Injury (iTBI): A CENTER-TBI Analysis

BACKGROUND

Trauma-induced coagulopathy in patients with traumatic brain injury (TBI) is associated with high rates of complications, unfavourable outcomes and mortality. The mechanism of the development of TBI-associated coagulopathy is poorly understood.

METHODS

This analysis, embedded in the prospective, multi-centred, observational Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study, aimed to characterise the coagulopathy of TBI. Emphasis was placed on the acute phase following TBI, primary on subgroups of patients with abnormal coagulation profile within 4 h of admission, and the impact of pre-injury anticoagulant and/or antiplatelet therapy. In order to minimise confounding factors, patients with isolated TBI (iTBI) (n = 598) were selected for this analysis.

RESULTS

Haemostatic disorders were observed in approximately 20% of iTBI patients. In a subgroup analysis, patients with pre-injury anticoagulant and/or antiplatelet therapy had a twice exacerbated coagulation profile as likely as those without premedication. This was in turn associated with increased rates of mortality and unfavourable outcome post-injury. A multivariate analysis of iTBI patients without pre-injury anticoagulant therapy identified several independent risk factors for coagulopathy which were present at hospital admission. Glasgow Coma Scale (GCS) less than or equal to 8, base excess (BE) less than or equal to - 6, hypothermia and hypotension increased risk significantly.

CONCLUSION

Consideration of these factors enables early prediction and risk stratification of acute coagulopathy after TBI, thus guiding clinical management.

Factors associated with the progression of traumatic intracranial hematoma during interventional radiology to establish hemostasis of extracranial hemorrhagic injury in severe multiple trauma patients

Aim

To identify factors affecting the progression of traumatic intracranial hemorrhagic injury (t‐ICH) during interventional radiology (IVR) for the hemostasis of extracranial hemorrhagic injury.

Methods

This was a retrospective comparative study. Fifty‐two patients with t‐ICH who underwent hemostasis using IVR for extracranial trauma at our institute were included. Clinical and computed tomography scan data were collected to investigate factors associated with t‐ICH progression.

Results

Fifty‐two subjects (36 men/16 women) with a mean age of 70.9 ± 19.2 years were analyzed. The mean Injury Severity Score was 34.9 ± 11.2. In 29 patients (55.7%), t‐ICH progressed during IVR. Hematoma progression frequently occurred in patients with acute subdural hematoma (56.2%) and traumatic intracerebral hematoma/hemorrhagic brain contusion (66.6%). Factors associated with t‐ICH progression included age (P = 0.029), consciousness level at admission (P = 0.001), Revised Trauma Scale (P = 0.036), probability of survival (P = 0.043), platelet count (P = 0.005), fibrinogen level (P = 0.016), hemoglobin level (P = 0.003), D‐dimer level (P = 0.046), and red blood cell transfusion volume (P = 0.023).

Conclusion

Aggressive correction of anemia, thrombocytopenia, and low fibrinogen levels in severe consciousness disturbance patients with acute subdural hematoma and traumatic intracerebral hematoma/hemorrhagic brain contusion could improve the prognosis after IVR for hemostasis of extracranial hemorrhagic injuries.

Von Willebrand factor as a thrombotic and inflammatory mediator in critical illness

The endothelial exocytosis of high-molecular-weight multimeric von Willebrand factor (vWF) may occur in critical illness states, including trauma and sepsis, leading to the sustained elevation and altered composition of plasma vWF. These critical illnesses involve the common process of sympathoadrenal activation and loss of the endothelial glycocalyx. As a prothrombotic and proinflammatory molecule that interacts with the endothelium, the alterations exhibited by vWF in critical illness have been implicated in the development and damaging effects of downstream pathologies, such as disseminated intravascular coagulation and systemic inflammatory response syndrome. Given the role of vWF in these pathologies, there has been a recent push to further understand how the molecule may be involved in the pathophysiology of related diseases, such as trauma-induced coagulopathy and acute renal injury, which are also known to develop secondarily to critical illness states. Elucidation of the role of vWF across the broader spectrum of generalized pathologies may provide a basis for the development of novel preventative and restorative measures, while also bolstering the scaffold of more widely used treatments, such as the administration of plasma-containing blood products.

Severe traumatic brain injury is associated with a unique coagulopathy phenotype

BACKGROUND

Traumatic brain injury (TBI) patients present on a spectrum from hypocoagulability to hypercoagulability, depending on the injury complexity, severity, and time since injury. Prior studies have found a unique coagulopathy associated with TBI using conventional coagulation assays such as INR; however, few studies have assessed the association of TBI and coagulopathy using viscoelastic assays that comprehensively evaluate the coagulation in whole blood. This study aims to reevaluate the TBI-specific trauma-induced coagulopathy using arrival thrombelastography. Because brain tissue is high in key procoagulant molecules, we hypothesize that isolated TBI is associated with procoagulant and hypofibrinolytic profiles compared with injuries of the torso, extremities, and polytrauma, including TBI.

METHODS

Data are from the prospective Trauma Activation Protocol study. Activated clotting time (ACT), angle, maximum amplitude (MA), 30-minute percent lysis after MA (LY30), and functional fibrinogen levels (FFLEV) were recorded. Patients were categorized into isolated severe TBI (I-TBI), severe TBI with torso and extremity injuries (TBI + TORSO/EXTREMITIES), and isolated torso and extremity injuries (I-TORSO/EXTREMITIES). Poisson regression was used to adjust for multiple confounders.

RESULTS

Overall, 572 patients (48 I-TBI, 45 TBI + TORSO/EXTREMITIES, 479 I-TORSO/EXTREMITIES) were included in this analysis. The groups differed in INR, ACT, angle, MA, and FFLEV but not in 30-minute percent lysis. When compared with I-Torso/Extremities, after adjustment for confounders, severe I-TBI was independently associated with ACT less than 128 seconds (relative risk [RR], 1.5; 95% confidence interval [CI], 1.1-2.2), angle less than 65 degrees (RR, 2.2; 95% CI, 1.4-3.6), FFLEV less than 356 (RR, 1.7; 95% CI, 1.2-2.4) but not MA less than 55 mm, hyperfibrinolysis, fibrinolysis shutdown, or partial thromboplastin time (PTT) greater than 30.

CONCLUSION

Severe I-TBI was independently associated with a distinct coagulopathy with delayed clot formation but did not appear to be associated with fibrinolysis abnormalities. Low fibrinogen and longer ACT values associated with I-TBI suggest that early coagulation factor replacement may be indicated in I-TBI patients over empiric antifibrinolytic therapy. Mechanisms triggering coagulopathy in TBI are unique and warrant further investigation.

LEVEL OF EVIDENCE

Retrospective cohort study, prognostic, level III.

Coagulopathy after hemorrhagic traumatic brain injury, an observational study of the incidence and prognosis

Background

Traumatic brain injury is associated with high rates of mortality and morbidity. Trauma patients with a coagulopathy have a 10-fold increased mortality risk compared to patients without a coagulopathy. The aim of this study was to identify the incidence of coagulopathy and relate early coagulopathy to clinical outcome in patients with traumatic intracranial hemorrhages.

Methods

Between September 2015 and December 2016, 108 consecutive cranial trauma patients with traumatic intracranial hemorrhages were included in this study. To assess the relationship between patients with a coagulopathy and outcome, a chi-squared test was performed.

Results

A total of 29 out of the 108 patients (27%) with a traumatic intracranial hemorrhage developed a coagulopathy within 72 h after admission. Overall, a total of 22 patients (20%) died after admission of which ten were coagulopathic at emergency department presentation. Early coagulopathy in patients with traumatic brain injury is associated with progression of hemorrhagic injury (odds ratio 2.4 (95% confidence interval 0.8–8.0)), surgical intervention (odds ratio 2.8 (95% confidence interval 0.87–9.35)), and increased in-hospital mortality (odds ratio 23.06 (95% confidence interval 5.5–95.9)).

Conclusion

Patients who sustained a traumatic intracranial hemorrhage remained at risk for developing a coagulopathy until 72 h after trauma. Patients who developed a coagulopathy had a worse clinical outcome than patients who did not develop a coagulopathy.

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

BACKGROUND

Progressive hemorrhagic injury (PHI) is common in patients with severe traumatic brain injury (TBI) and is associated with poor outcomes. TBI-associated coagulopathy is frequent and has been described as risk factor for PHI. This coagulopathy is a dynamic process involving hypercoagulable and hypocoagulable states either one after the other either concomitant. Fibrin monomers (FMs) are a direct marker of thrombin action and thus reflect coagulation activation. This study sought to determine the ability of FM to predict PHI after severe TBI.

METHODS

We conducted a prospective, observational study including all severe TBI patients admitted in the trauma center. Between September 2011 and September 2016, we enrolled patients with severe TBI into the derivation cohort. Between October 2016 and December 2018, we recruited the validation cohort on the same basis. Study protocol included FM measurements and standard coagulation test at admission and two computed tomography (CT) scans (upon arrival and at least 6 h thereafter). A PHI was defined by an increment in size of initial lesion (25% or more) or the development of a new hemorrhage in the follow-up CT scan. Multivariate logistic regression analysis was applied to identify predictors of PHI.

RESULTS

Overall, 106 patients were included in the derivation cohort. Fifty-four (50.9%) experienced PHI. FM values were higher in these patients (151 [136.8-151] vs. 120.5 [53.3-151], p < 0.0001). The ROC curve demonstrated that FM had a fair accuracy to predict the occurrence of PHI with an area under curve of 0.7 (95% CI [0.6-0.79]). The best threshold was determined at 131.7 μg/ml. In the validation cohort of 54 patients, this threshold had a negative predictive value of 94% (95% CI [71-100]) and a positive predictive value of 49% (95% CI [32-66]). The multivariate logistic regression analysis identified 2 parameters associated with PHI: FM ≥ 131.7 (OR 6.8; 95% CI [2.8-18.1]) and Marshall category (OR 1.7; 95% CI [1.3-2.2]). Coagulopathy was not associated with PHI (OR 1.3; 95% CI [0.5-3.0]). The proportion of patients with an unfavorable functional neurologic outcome at 6-months follow-up was higher in patients with positive FM: 59 (62.1%) versus 16 (29.1%), p < 0.0001.

CONCLUSIONS

FM levels at admission had a fair accuracy to predict PHI in patients with severe TBI. FM values ≥ 131.7 μg/ml are independently associated with the occurrence of PHI.

Trauma-induced coagulopathy: The past, present, and future

Trauma remains a leading cause of death worldwide, and most early preventable deaths in both the civilian and military settings are due to uncontrolled hemorrhage, despite paradigm advances in modern trauma care. Combined tissue injury and shock result in hemostatic failure, which has been identified as a multidimensional molecular, physiologic and clinical disorder termed trauma-induced coagulopathy (TIC). Understanding the biology of TIC is of utmost importance, as it is often responsible for uncontrolled bleeding, organ failure, thromboembolic complications, and death. Investigations have shown that TIC is characterized by multiple phenotypes of impaired hemostasis due to altered biology in clot formation and breakdown. These coagulopathies are attributable to tissue injury and shock, and encompass underlying endothelial, immune and inflammatory perturbations. Despite the recognition and identification of multiple mechanisms and mediators of TIC, and the development of targeted treatments, the mortality rates and associated morbidities due to hemorrhage after injury remain high. The purpose of this review is to examine the past and present understanding of the multiple distinct but highly integrated pathways implicated in TIC, in order to highlight the current knowledge gaps and future needs in this evolving field, with the aim of reducing morbidity and mortality after injury.

Diagnostic and therapeutic approach in adult patients with traumatic brain injury receiving oral anticoagulant therapy: an Austrian interdisciplinary consensus statement

There is a high degree of uncertainty regarding optimum care of patients with potential or known intake of oral anticoagulants and traumatic brain injury (TBI). Anticoagulation therapy aggravates the risk of intracerebral hemorrhage but, on the other hand, patients take anticoagulants because of an underlying prothrombotic risk, and this could be increased following trauma. Treatment decisions must be taken with due consideration of both these risks. An interdisciplinary group of Austrian experts was convened to develop recommendations for best clinical practice. The aim was to provide pragmatic, clear, and easy-to-follow clinical guidance for coagulation management in adult patients with TBI and potential or known intake of platelet inhibitors, vitamin K antagonists, or non-vitamin K antagonist oral anticoagulants. Diagnosis, coagulation testing, and reversal of anticoagulation were considered as key steps upon presentation. Post-trauma management (prophylaxis for thromboembolism and resumption of long-term anticoagulation therapy) was also explored. The lack of robust evidence on which to base treatment recommendations highlights the need for randomized controlled trials in this setting.

The procoagulant molecule plasminogen activator inhibitor-1 is associated with injury severity and shock in patients with and without traumatic brain injury

BACKGROUND

Traumatic injury is associated with an increased risk of coagulopathy and venous thrombosis. plasminogen activator inhibitor-1 (PAI-1) is a procoagulant molecule that inhibits tPA/uPA, thrombomodulin, and activated protein C. We hypothesized that elevated PAI-1 levels would be associated with increased Injury Severity Score (ISS) in injured patients with and without traumatic brain injury and that PAI-1 levels would vary with injury type.

METHODS

We retrospectively analyzed demographic, ISS, and hemodynamic data from a prospectively collected database. Patients with traumatic injury requiring intensive care unit admission (n = 268) were classified as multiple injuries, isolated body, or isolated head based on Abbreviated Injury Severity score. Admission PAI-1 levels were quantified using a Luminex analyte platform. Univariate tests for association informed the construction of a multivariate model of the relationship between PAI-1 and ISS.

RESULTS

Plasminogen activator inhibitor-1 positively associated with ISS (p < 0.0001) and was highest in patients with ISS greater than 35 (p < 0.0001). Plasminogen activator inhibitor-1 was significantly different between multiple injuries, isolated body, and isolated head patients (p < 0.0001). On univariate analysis, age (p = 0.0011), hypotension (p = 0.0076), and alcohol intoxication (p = 0.0024) were all positively associated with PAI-1 level. Admission international normalized ratio was not associated with PAI-1 level (p = 0.638). After adjusting for age, sex, hypotension, and alcohol intoxication, higher PAI-1 levels were associated with higher ISS (p < 0.0001).

CONCLUSION

Elevated PAI-1 at admission is associated with higher ISS. This association is more pronounced in patients with hypotension. These findings suggest that PAI-1 levels may reflect the burden of endothelial damage and platelet activation after injury.

LEVEL OF EVIDENCE

Prognostic, level III.

Neuroanesthesiology Update

We provide a synopsis of innovative research, recurring themes, and novel experimental findings pertinent to the care of neurosurgical patients and critically ill patients with neurological diseases. We cover the following broad topics: general neurosurgery, spine surgery, stroke, traumatic brain injury, monitoring, and anesthetic neurotoxicity.

Activated protein C plays no major roles in the inhibition of coagulation or increased fibrinolysis in acute coagulopathy of trauma-shock: a systematic review

Background

The pathophysiological mechanisms of acute coagulopathy of trauma-shock (ACOTS) are reported to include activated protein C-mediated suppression of thrombin generation via the proteolytic inactivation of activated Factor V (FVa) and FVIIIa; an increased fibrinolysis via neutralization of plasminogen activator inhibitor-1 (PAI-1) by activated protein C. The aims of this study are to review the evidences for the role of activated protein C in thrombin generation and fibrinolysis and to validate the diagnosis of ACOTS based on the activated protein C dynamics.

Methods

We conducted systematic literature search (2007–2017) using PubMed, the Cochrane Database of Systematic Reviews (CDSR), and the Cochrane Central Register of Controlled Trials (CENTRAL). Clinical studies on trauma that measured activated protein C or the circulating levels of activated protein C-related coagulation and fibrinolysis markers were included in our study.

Results

Out of 7613 studies, 17 clinical studies met the inclusion criteria. The levels of activated protein C in ACOTS were inconsistently decreased, showed no change, or were increased in comparison to the control groups. Irrespective of the activated protein C levels, thrombin generation was always preserved or highly elevated. There was no report on the activated protein C-mediated neutralization of PAI-1 with increased fibrinolysis. No included studies used unified diagnostic criteria to diagnose ACOTS and those studies also used different terms to refer to the condition known as ACOTS.

Conclusions

None of the studies showed direct cause and effect relationships between activated protein C and the suppression of coagulation and increased fibrinolysis. No definitive diagnostic criteria or unified terminology have been established for ACOTS based on the activated protein C dynamics.

Electronic supplementary material

The online version of this article (10.1186/s12959-018-0167-3) contains supplementary material, which is available to authorized users.

Neutrophils in traumatic brain injury (TBI): friend or foe?

Our knowledge of the pathophysiology about traumatic brain injury (TBI) is still limited. Neutrophils, as the most abundant leukocytes in circulation and the first-line transmigrated immune cells at the sites of injury, are highly involved in the initiation, development, and recovery of TBI. Nonetheless, our understanding about neutrophils in TBI is obsolete, and mounting evidences from recent studies have challenged the conventional views. This review summarizes what is known about the relationships between neutrophils and pathophysiology of TBI. In addition, discussions are made on the complex roles as well as the controversial views of neutrophils in TBI.

Low Plasma ADAMTS13 Activity Is Associated with Coagulopathy, Endothelial Cell Damage and Mortality after Severe Paediatric Trauma

Decrease of plasma activity of ADAMTS13, a metalloenzyme that cleaves von Willebrand factor (VWF) and prevents adhesion and aggregation of platelets, has been reported early after onset of systemic inflammation resulting from infections and after severe trauma. Here, we determined whether trauma-induced systemic (sterile) inflammation would be associated with a reduction of plasma ADAMTS13 activity in paediatric patients and its association with disease severity and outcome. Paediatric patients (n = 106) with severe trauma at a level 1 paediatric trauma centre between 2014 and 2016 were prospectively enrolled. Blood samples were collected upon arrival and at 24 hours and analysed for plasma levels of ADAMTS13 activity, VWF antigen, collagen binding activity, human neutrophil peptides (HNP) 1-3, coagulation abnormalities, endothelial glycocalyx damage and clinical outcome. Plasma samples were also collected for similar measurements from 52 healthy paediatric controls who underwent elective minor surgery. The median age of patients was 9 years with 81% sustaining blunt trauma. The median injury severity score was 22 and the mortality rate was 11%. Plasma levels of ADAMTS13 activity were significantly lower and plasma levels of VWF antigen and HNP 1-3 proteins were significantly higher for paediatric trauma patients on admission and at 24 hours when compared with controls. Finally, the lowest plasma ADAMTS13 activity was found in patients who died from their injuries. We conclude that relative plasma deficiency of ADAMTS13 activity may be associated with more severe traumatic injury, significant endothelial glycocalyx damage, coagulation abnormalities and mortality after severe trauma in paediatric patients.

Factor VIIa administration in traumatic brain injury: an AAST-MITC propensity score analysis

BACKGROUND

Recombinant factor VIIa (rFVIIa) has been used off-label as an adjunct in the reversal of warfarin therapy and management of hemorrhage after trauma. Only a handful of these reports are rigorous studies, from which results regarding safety and effectiveness have been mixed. There remains no clear consensus as to the role of rFVIIa in traumatic brain injury (TBI).

METHODS

Eleven level 1 trauma centers provided clinical data and head CT scans of patients with a Glasgow Coma Scale (GCS) score of ≤13 and radiographic evidence of TBI. A propensity score (PS) to receive rFVIIa in those surviving ≥2 days was calculated for each patient based on patient demographics, comorbidities, physiology, Injury Severity Score, admission GCS score, and treatment center. Patients receiving rFVIIa within 24 hours of admission were matched to patients who did not receive rFVIIa for outcomes assessment. Subgroup analysis evaluated patients with primary head injury with PS matching.

RESULTS

There were 4284 patient observations; 129 received rFVIIa. Groups were comparable after matching. No differences in mortality or morbidity were found. Improvement in GCS score from admission to discharge was less among those receiving rFVIIa (5.5 vs. 2.4; P value 0.001); however, there was no difference in average GCS score at discharge. No significant differences in outcomes were identified in patients with isolated TBI receiving rFVIIa.

DISCUSSION

rFVIIa in early management of TBI is not associated with a decreased risk of mortality or morbidity, and may negatively impact recovery and functional status at discharge in the severely injured patient with polytrauma.

LEVEL OF EVIDENCE

Level III.

STUDY TYPE

Therapeutic/care management.

Sympathoadrenal Activation is Associated with Acute Traumatic Coagulopathy and Endotheliopathy in Isolated Brain Injury

Background:

Acute coagulopathy after traumatic brain injury (TBI) involves a complex multifactorial hemostatic response that is poorly characterized. Objectives: To examine early posttraumatic alterations in coagulofibrinolytic, endothelial, and inflammatory blood biomarkers in relation to sympathetic nervous system (SNS) activation and 6-month patient outcomes, using multivariate partial least-squares (PLS) analysis.

Patients and Methods:

A multicenter observational study of 159 adult isolated TBI patients admitted to the emergency department at an urban level I trauma center, was performed. Plasma concentrations of 6 coagulofibrinolytic, 10 vascular endothelial, 19 inflammatory, and 2 catecholamine biomarkers were measured by immunoassay on admission and 24 h postinjury. Neurological outcome at 6 months was assessed using the Extended Glasgow Outcome Scale. PLS-discriminant analysis was used to identify salient biomarker contributions to unfavorable outcome, whereas PLS regression analysis was used to evaluate the covariance between SNS correlates (catecholamines) and biomarkers of coagulopathy, endotheliopathy, and inflammation.

Results:

Biomarker profiles in patients with an unfavorable outcome displayed procoagulation, hyperfibrinolysis, glycocalyx and endothelial damage, vasculature activation, and inflammation. A strong covariant relationship was evident between catecholamines and biomarkers of coagulopathy, endotheliopathy, and inflammation at both admission and 24 h postinjury.

Conclusions:

Biomarkers of coagulopathy and endotheliopathy are associated with poor outcome after TBI. Catecholamine levels were highly correlated with endotheliopathy and coagulopathy markers within the first 24 h after injury. Further research is warranted to characterize the pathogenic role of SNS-mediated hemostatic alterations in isolated TBI.

Comparative Study of Derangement of Coagulation Profile between Adult and Pediatric Population in Moderate to Severe Traumatic Brain Injury: A Prospective Study in a Tertiary Care Trauma Center

Object:

Coagulopathy is a common occurrence following traumatic brain injury (TBI). There are various studies showing incidence and risk factors of coagulopathy and their correlation with poor outcome in adult as well as paediatric age groups. Exact incidence, associated risk factors, treatment guideline for coagulopathy and its impact on outcome are still lacking. In our study we compared the adults and paediatric age groups TBI patients for incidence and risk factors of coagulopathy and its impact on outcome.

Methods:

Prospective study of 200 patients including 152 adult patients (age > 18 years) and 48 paediatric (Age < 18 years) patients of TBI admitted in intensive care unit of trauma centre of a tertiary care centre was performed from august 2015 to march 2016. Both population were further subdivided into moderate TBI and severe TBI as per Glasgow coma score (GCS). Patient with long bone injury, chest injury and abdominal injuries, coagulation disorder, liver disease, medical disease like diabetes mellitus and hypertension were excluded from study. Coagulation profile were compared in the both groups (Adult and paediatric) and correlated with the outcome. Chi- Square test, student t test and Odds ratios were used for statistical analysis.

Results:

Mean age among the adult and paediatric population were 37.89 ± 11.88 years and 11.41 ± 5.90, respectively. Among the patient with moderate TBI, coagulopathy was seen in 30% patients of adult TBI whereas it was 12.5% among the paediatric TBI (P = 0.185). Among the severe TBI group coagulopathy was observed in 68.03% and 37.5% of adult and paediatric age group respectively (P = 0.0016). There was significant correlation found between midline shift and coagulopathy in the paediatric age group (P = 0.022; OR - 4.58). E. There was significant association of coagulopathy and contusion on CT scan among the adult population (P = 0.007; OR - 3.487) found whereas no such correlation were observed in paediatric population.

Conclusion:

Coagulopathy was significantly higher among the adult patient with severe TBI as compare to paediatric patient with severe TBI. There was no statistically significant difference in mortality among patients of both the age groups with coagulopathy.

Non- Neurological Complications after Traumatic Brain Injury: A Prospective Observational Study

Introduction and Aims

Recognizing and treating nonneurological complications occurring in traumatic brain injury (TBI) patients during intensive care unit (ICU) stay are challenging. The aim is to estimate various nonneurological complications in TBI patients. The secondary aim is to see the effect of these complications on ICU stay, disability, and mortality.

Materials and Methods

This was a prospective observational study at the neuro-ICU of a Level-I trauma center. A total of 154 TBI patients were enrolled. The period of the study was from admission to discharge from ICU or demise. Inclusion criteria were patients aged >16 years and patients with severe TBI (Glasgow coma score [GCS] ≤8). Nonneurological complications were frequent in TBI patients.

Results

We observed respiratory complications to be the most common (61%). Other complications, in the decreasing order, included dyselectrolytemia (46.1%), cardiovascular (34.4%), coagulopathy (33.1%), sepsis (26%), abdominal complications (17.5%), and acute kidney injury (AKI, 3.9%). The presence of systemic complications except AKI was found to be significantly associated with increased ICU stay. Most of the patients of AKI died early in ICU. Respiratory dysfunction was found to be independently associated with 3.05 times higher risk of worsening clinical condition (disability) (P < 0.018). The presence of cardiovascular complications during ICU stay (4.2 times, P < 0.005), AKI (24.7 times, P < 0.02), coagulopathy (3.13 times, P < 0.047), and GCS <6 (4.2 times, P < 0.006) of TBI was independently associated with significantly increased risk of ICU mortality.

Conclusion

TBI patients tend to have poor outcome due to concomitant nonneurological complications. These have significant bearing on ICU stay, disability, and mortality.

Acute Traumatic Coagulopathy Accompanying Isolated Traumatic Brain Injury is Associated with Worse Long-Term Functional and Cognitive Outcomes

BACKGROUND

Approximately one-third of patients with isolated traumatic brain injury (iTBI) present with acute traumatic coagulopathy (ATC). ATC is associated with increased morbidity and mortality. Its effects on long-term functional and cognitive outcomes are not as well characterized.

METHODS

Data from the Citicoline Brain Injury Treatment Trial (COBRIT) were analyzed retrospectively. Exclusion criteria were renal failure or malignancy, and any extracranial injury severity score >3. ATC was defined as INR > 1.3, PTT > 38 s, or platelets < 100 K, determined at baseline, and during the first 7 days of hospitalization.

RESULTS

Six hundred forty-seven patients were included; 21 % were found to have ATC. Highest incidence occurred at baseline, and Day Two. Forty-two percent of ATC patients had a GCS < 8, compared with 11.3 % of non-ATC patients (p < 0.001). A significantly higher proportion of ATC patients was transfused blood products, required greater than 4L of fluids, demonstrated hyperthermia and hypothermia, were hypotensive and demonstrated elevated lactate when compared to non-ATC patients. In-hospital mortality, mean hospital length of stay, incidence of DVT and seizures were also significantly higher in ATC patients. A significantly lower portion of ATC patients had good outcomes on the GOS-E (i.e., score > 6), and the DRS (i.e., score < 2) at 180 days, for which ATC was found to be an independent predictor with binary logistic regression. ATC patients also performed significantly worse on several components of the CVLT-II at 180 days.

CONCLUSIONS

ATC accompanying iTBI is associated with worse functional and cognitive outcomes at 180 days.

Acute Management of Traumatic Brain Injury

Traumatic brain injury (TBI) is a leading cause of death and disability in patients with trauma. Management strategies must focus on preventing secondary injury by avoiding hypotension and hypoxia and maintaining appropriate cerebral perfusion pressure (CPP), which is a surrogate for cerebral blood flow. CPP can be maintained by increasing mean arterial pressure, decreasing intracranial pressure, or both. The goal should be euvolemia and avoidance of hypotension. Other factors that deserve important consideration in the acute management of patients with TBI are venous thromboembolism, stress ulcer, and seizure prophylaxis, as well as nutritional and metabolic optimization.

Prehospital plasma resuscitation associated with improved neurologic outcomes after traumatic brain injury

BACKGROUND

Trauma-related hypotension and coagulopathy worsen secondary brain injury in patients with traumatic brain injuries (TBIs). Early damage control resuscitation with blood products may mitigate hypotension and coagulopathy. Preliminary data suggest resuscitation with plasma in large animals improves neurologic function after TBI; however, data in humans are lacking.

METHODS

We retrospectively identified all patients with multiple injuries age >15 years with head injuries undergoing prehospital resuscitation with blood products at a single Level I trauma center from January 2002 to December 2013. Inclusion criteria were prehospital resuscitation with either packed red blood cells (pRBCs) or thawed plasma as sole colloid resuscitation. Patients who died in hospital and those using anticoagulants were excluded. Primary outcomes were Glasgow Outcomes Score Extended (GOSE) and Disability Rating Score (DRS) at dismissal and during follow-up.

RESULTS

Of 76 patients meeting inclusion criteria, 53% (n = 40) received prehospital pRBCs and 47% (n = 36) received thawed plasma. Age, gender, injury severity or TBI severity, arrival laboratory values, and number of prehospital units were similar (all p > 0.05). Patients who received thawed plasma had an improved neurologic outcome compared to those receiving pRBCs (median GOSE 7 [7-8] vs. 5.5 [3-7], p < 0.001). Additionally, patients who received thawed plasma had improved functionality compared to pRBCs (median DRS 2 [1-3.5] vs. 9 [3-13], p < 0.001). Calculated GOSE and DRS scores during follow-up, median 6 [5-7] months, demonstrated increased function in those resuscitated with thawed plasma compared to pRBCs by both median GOSE (8 [7-8] vs. 6 [6-7], p < 0.001) and DRS (0 [0-1] vs. 4 [2-8], p < 0.001).

CONCLUSION

In critically injured trauma patients with TBI, early resuscitation with thawed plasma is associated with improved neurologic and functional outcomes at discharge and during follow-up compared to pRBCs alone. These preliminary data support the further investigation and use of plasma in the resuscitation of critically injured TBI patients.

LEVEL OF EVIDENCE

Therapeutic, level V.

Hyperfibrinolysis in severe isolated traumatic brain injury may occur without tissue hypoperfusion: a retrospective observational multicentre study

BACKGROUND

Hyperfibrinolysis is a critical complication in severe trauma. Hyperfibrinolysis is traditionally diagnosed via elevated D-dimer or fibrin/fibrinogen degradation product levels, and recently, using thromboelastometry. Although hyperfibrinolysis is observed in patients with severe isolated traumatic brain injury (TBI) on arrival at the emergency department (ED), it is unclear which factors induce hyperfibrinolysis. The present study aimed to investigate the factors associated with hyperfibrinolysis in patients with isolated severe TBI.

METHODS

We conducted a multicentre retrospective review of data for adult trauma patients with an injury severity score ≥ 16, and selected patients with isolated TBI (TBI group) and extra-cranial trauma (non-TBI group). The TBI group included patients with an abbreviated injury score (AIS) for the head ≥ 4 and an extra-cranial AIS < 2. The non-TBI group included patients with an extra-cranial AIS ≥ 3 and head AIS < 2. Hyperfibrinolysis was defined as a D-dimer level ≥ 38 mg/L on arrival at the ED. We evaluated the relationships between hyperfibrinolysis and injury severity/tissue injury/tissue perfusion in TBI patients by comparing them with non-TBI patients.

RESULTS

We enrolled 111 patients in the TBI group and 126 in the non-TBI group. In both groups, patients with hyperfibrinolysis had more severe injuries and received transfusion more frequently than patients without hyperfibrinolysis. Tissue injury, evaluated on the basis of lactate dehydrogenase and creatine kinase levels, was associated with hyperfibrinolysis in both groups. Among patients with TBI, the mortality rate was higher in those with hyperfibrinolysis than in those without hyperfibrinolysis. Tissue hypoperfusion, evaluated on the basis of lactate level, was associated with hyperfibrinolysis in only the non-TBI group. Although the increase in lactate level was correlated with the deterioration of coagulofibrinolytic variables (prolonged prothrombin time and activated partial thromboplastin time, decreased fibrinogen levels, and increased D-dimer levels) in the non-TBI group, no such correlation was observed in the TBI group.

CONCLUSIONS

Hyperfibrinolysis is associated with tissue injury and trauma severity in TBI and non-TBI patients. However, tissue hypoperfusion is associated with hyperfibrinolysis in non-TBI patients, but not in TBI patients. Tissue hypoperfusion may not be a prerequisite for the occurrence of hyperfibrinolysis in patients with isolated TBI.

Characterization of distinct coagulopathic phenotypes in injury: Pathway-specific drivers and implications for individualized treatment

BACKGROUND

International normalized ratio (INR) and partial thromboplastin time (PTT) are used interchangeably to diagnose acute traumatic coagulopathy but reflect disparate activation pathways. In this study, we identified injury/patient characteristics and coagulation factors that drive contact pathway, tissue factor pathway (TF), and common pathway dysfunction by examining injured patients with discordant coagulopathies. We hypothesized that patients with INR/PTT discordance reflect differing phenotypes representing contact versus tissue factor pathway perturbations and that characterization will provide targets to guide individualized resuscitation.

METHODS

Plasma samples were prospectively collected from 1,262 critically injured patients at a single Level I trauma center. Standard coagulation measures and an extensive panel of procoagulant and anticoagulant factors were assayed and analyzed with demographic and outcome data.

RESULTS

Fourteen percent of patients were coagulopathic on admission. Among these, 48% had abnormal INR and PTT (BOTH), 43% had isolated prolonged PTT (PTT-CONTACT), and 9% had isolated elevated INR (INR-TF). PTT-CONTACT and BOTH had lower Glasgow Coma Scale score than INR-TF (p < 0.001). INR-TF had decreased factor VII activity compared with PTT-CONTACT, whereas PTT-CONTACT had decreased factor VIII activity compared with INR-TF. All coagulopathic patients had factor V deficits, but activity was lowest in BOTH, suggesting an additive downstream effect of disordered activation pathways. Patients with PTT-CONTACT received half as much packed red blood cell and fresh frozen plasma as did the other groups (p < 0.001). Despite resuscitation, mortality was higher for coagulopathic patients; mortality was highest in BOTH and higher in PTT-CONTACT than in INR-TF (71%, 60%, 41%; p = 0.04).

CONCLUSIONS

Discordant phenotypes demonstrate differential factor deficiencies consistent with dysfunction of contact versus tissue factor pathways with additive effects from common pathway dysfunction. Recognition and treatment of pathway-specific factor deficiencies driving different coagulopathic phenotypes in injured patients may individualize resuscitation and improve outcomes.

LEVEL OF EVIDENCE

Prognostic/epidemiological study, level II.

Coagulopathy in the Setting of Mild Traumatic Brain Injury: Truths and Consequences

Mild traumatic brain injury (mTBI) is a common, although poorly-defined clinical entity. Despite its initially mild presentation, patients with mTBI can rapidly deteriorate, often due to significant expansion of intracranial hemorrhage. TBI-associated coagulopathy is the topic of significant clinical and basic science research. Unlike trauma-induced coagulopathy (TIC), TBI-associated coagulopathy does not generally follow widespread injury or global hypoperfusion, suggesting a distinct pathogenesis. Although the fundamental mechanisms of TBI-associated coagulopathy are far from clearly elucidated, several candidate molecules (tissue plasminogen activator (tPA), urokinase plasminogen activator (uPA), tissue factor (TF), and brain-derived microparticles (BDMP)) have been proposed which might explain how even minor brain injury can induce local and systemic coagulopathy. Here, we review the incidence, proposed mechanisms, and common clinical tests relevant to mTBI-associated coagulopathy and briefly summarize our own institutional experience in addition to identifying areas for further research.

Activated Protein C Drives the Hyperfibrinolysis of Acute Traumatic Coagulopathy

BACKGROUND

Major trauma is a leading cause of morbidity and mortality worldwide with hemorrhage accounting for 40% of deaths. Acute traumatic coagulopathy exacerbates bleeding, but controversy remains over the degree to which inhibition of procoagulant pathways (anticoagulation), fibrinogen loss, and fibrinolysis drive the pathologic process. Through a combination of experimental study in a murine model of trauma hemorrhage and human observation, the authors' objective was to determine the predominant pathophysiology of acute traumatic coagulopathy.

METHODS

First, a prospective cohort study of 300 trauma patients admitted to a single level 1 trauma center with blood samples collected on arrival was performed. Second, a murine model of acute traumatic coagulopathy with suppressed protein C activation via genetic mutation of thrombomodulin was used. In both studies, analysis for coagulation screen, activated protein C levels, and rotational thromboelastometry (ROTEM) was performed.

RESULTS

In patients with acute traumatic coagulopathy, the authors have demonstrated elevated activated protein C levels with profound fibrinolytic activity and early depletion of fibrinogen. Procoagulant pathways were only minimally inhibited with preservation of capacity to generate thrombin. Compared to factors V and VIII, proteases that do not undergo activated protein C-mediated cleavage were reduced but maintained within normal levels. In transgenic mice with reduced capacity to activate protein C, both fibrinolysis and fibrinogen depletion were significantly attenuated. Other recognized drivers of coagulopathy were associated with less significant perturbations of coagulation.

CONCLUSIONS

Activated protein C-associated fibrinolysis and fibrinogenolysis, rather than inhibition of procoagulant pathways, predominate in acute traumatic coagulopathy. In combination, these findings suggest a central role for the protein C pathway in acute traumatic coagulopathy and provide new translational opportunities for management of major trauma hemorrhage.

Blood transfusion indications in neurosurgical patients: A systematic review

Neurosurgical procedures can be complicated by significant blood losses that have the potential to decrease tissue perfusion to critical brain tissue. Red blood cell transfusion is used in a variety of capacities both inside, and outside, of the operating room to prevent untoward neurologic damage. However, evidence-based guidelines concerning thresholds and indications for transfusion in neurosurgery remain limited. Consequently, transfusion practices in neurosurgical patients are highly variable and based on institutional experiences. Recently, a paradigm shift has occurred in neurocritical intensive care units, whereby restrictive transfusion is increasingly favored over liberal transfusion but the ideal strategy remains in clinical equipoise. The authors of this study perform a systematic review of the literature with the objective of capturing the changing landscape of blood transfusion indications in neurosurgical patients.

Management of neurologic complications of coagulopathies

Coagulopathy is common in intensive care units (ICUs). Many physiologic derangements lead to dysfunctional hemostasis; these may be either congenital or acquired. The most devastating outcome of coagulopathy in the critically ill is major bleeding, defined by transfusion requirement, hemodynamic instability, or intracranial hemorrhage. ICU coagulopathy often poses complex management dilemmas, as bleeding risk must be tempered with thrombotic potential. Coagulopathy associated with intracranial hemorrhage bears directly on prognosis and outcome. There is a paucity of high-quality evidence for the management of coagulopathies in neurocritical care; however, data derived from studies of patients with intraparenchymal hemorrhage may inform treatment decisions. Coagulopathy is often broadly defined as any derangement of hemostasis resulting in either excessive bleeding or clotting, although most typically it is defined as impaired clot formation. Abnormalities in coagulation testing without overt clinical bleeding may also be considered evidence of coagulopathy. This chapter will focus on acquired conditions, such as organ failure, pharmacologic therapies, and platelet dysfunction that are associated with defective clot formation and result in, or exacerbate, intracranial hemorrhage, specifically spontaneous intraparenchymal hemorrhage and traumatic brain injury.

Relationship between tissue perfusion and coagulopathy in traumatic brain injury

BACKGROUND

Traumatic brain injury (TBI)-related coagulopathy appears to be most prevalent in patients with tissue hypoperfusion, but evidence for this association is scarce. This study investigated the relationship between tissue perfusion and hemostatic derangements in TBI patients.

MATERIALS AND METHODS

Coagulation parameters were measured on emergency department admission in patients with TBI (head abbreviated injury scale ≥ 3). The level of hypoperfusion was simultaneously assessed by near-infrared spectroscopy (NIRS) at the forehead and arm, and by base excess and lactate. Coagulopathy was defined as an international normalized ratio > 1.2 and/or activated partial thromboplastin time > 40 s and/or thrombocytopenia (<120 × 10(9)/L).

RESULTS

TBI patients with coagulopathy (42%) had more signs of tissue hypoperfusion as indicated by increased lactate levels (2.1 [1.1-3.2] mmol/L versus 1.2 [1.0-1.7] mmol/L; P = 0.017) and a larger base deficit (-3.0 [-4.6 to -2.0] mmol/L versus -0.1 [-2.5 to 1.8] mmol/L; P < 0.001). There was no difference in the cerebral or somatic tissue oxygenation index. However, there was a distinct trend toward a moderate inverse association between the cerebral tissue oxygenation index and D-dimer levels (r=-0.40; P = 0.051) as marker of fibrinolysis. The presence of coagulopathy was associated with an increased inhospital mortality rate (45.5% versus 6.7%; P = 0.002).

CONCLUSIONS

This is the first study to investigate the relationship between hemostatic derangements and tissue oxygenation using NIRS in TBI patients. This study showed that TBI-related coagulopathy is more profound in patients with metabolic acidosis and increased lactate levels. Although there was no direct relationship between tissue oxygenation and coagulopathy, we observed an inverse relationship between NIRS tissue oxygenation levels and fibrinolysis.

Influence of surgical bleeding on the relationship between admission coagulopathy and risk of massive transfusion: lesson from 704 severe trauma patients

BACKGROUND

This study hypothesized that the relationship between early coagulopathy and massive transfusion (MT) in trauma was highly dependent on the presence of surgical bleeding.

METHODS

Consecutive severe trauma patients admitted to our institution over a 4-year period were included in this retrospective study. Surgical bleeding was defined as an injury requiring an invasive endovascular or surgical haemostatic procedure. The ability of prothrombin time ratio (PTr) and activated partial thromboplastin time ratio (aPTTr) to predict MT (≥10 units of packed red blood cells during the first 24 h) was determined by ROC curves. The strength of association and interaction between PTr, surgical bleeding and MT was assessed using a logistic regression analysis.

RESULTS

Among the 704 patients included (ISS 21·0 ± 16·2), MT rate was higher in patients with surgical bleeding than in those with no surgical bleeding (47% vs. 5%; P < 0·001). The global performance of PTr and aPTTr to predict MT was only fair in our study population (AUCs 0·83 and 0·81). MT rate was widely higher in the surgical bleeding group whatever the severity of coagulopathy (P < 0·001). PTr was found to be significantly associated with TM [PTr ≥ 1·5, OR 23·6 (95% CI 13·4-41·7); PTr 1·2-1·5, OR 3·0 (95% CI 1·7-5·3)]. Corresponding ORs were reduced after adjusting for the surgical bleeding: 12·1 (95% CI 6·5-22·5) and 2·1 (95% CI 1·2-4·0), respectively. However, no significant interaction was found regression models.

CONCLUSION

The strength of association between MT and coagulation status on admission was found strongly influenced by surgical bleeding. The admission coagulopathy monitoring in trauma patients without considering the surgical bleeding does not allow a reliable determination of MT probability.