Traumatic brain injury is not associated with coagulopathy out of proportion to injury in other body regions

A metabolomic and proteomic analysis of pathologic hypercoagulability in traumatic brain injury patients after dura violation

BACKGROUND

The coagulopathy of traumatic brain injury (TBI) remains poorly understood. Contradictory descriptions highlight the distinction between systemic and local coagulation, with descriptions of systemic hypercoagulability despite intracranial hypocoagulopathy. This perplexing coagulation profile has been hypothesized to be due to tissue factor release. The objective of this study was to assess the coagulation profile of TBI patients undergoing neurosurgical procedures. We hypothesize that dura violation is associated with higher tissue factor and conversion to a hypercoagulable profile and unique metabolomic and proteomic phenotype.

METHODS

This is a prospective, observational cohort study of all adult TBI patients at an urban, Level I trauma center who underwent a neurosurgical procedure from 2019 to 2021. Whole blood samples were collected before and then 1 hour following dura violation. Citrated rapid and tissue plasminogen activator (tPA) thrombelastography (TEG) were performed, in addition to measurement of tissue factory activity, metabolomics, and proteomics.

RESULTS

Overall, 57 patients were included. The majority (61%) were male, the median age was 52 years, 70% presented after blunt trauma, and the median Glasgow Coma Score was 7. Compared with pre-dura violation, post-dura violation blood demonstrated systemic hypercoagulability, with a significant increase in clot strength (maximum amplitude of 74.4 mm vs. 63.5 mm; p < 0.0001) and a significant decrease in fibrinolysis (LY30 on tPAchallenged TEG of 1.4% vs. 2.6%; p = 0.04). There were no statistically significant differences in tissue factor. Metabolomics revealed notable increases in metabolites involved in late glycolysis, cysteine, and one-carbon metabolites, and metabolites involved in endothelial dysfunction/arginine metabolism/responses to hypoxia. Proteomics revealed notable increase in proteins related to platelet activation and fibrinolysis inhibition.

CONCLUSION

A systemic hypercoagulability is observed in TBI patients, characterized by increased clot strength and decreased fibrinolysis and a unique metabolomic and proteomics phenotype independent of tissue factor levels.

Multiplate Platelet Function Testing upon Emergency Room Admission Fails to Provide Useful Information in Major Trauma Patients Not on Platelet Inhibitors

Platelet dysfunction is a suggested driver of trauma-induced coagulopathy. However, there is still a paucity of data regarding the impact of injury pattern on platelet function and the association of platelet dysfunction on transfusion requirements and mortality. In this retrospective cohort study, patients were grouped into those with isolated severe traumatic brain injury (TBI group), those with major trauma without TBI (MT group), and a combination of both major trauma and traumatic brain injury (MT + TBI group). Platelet function was assessed by whole blood impedance aggregometry (Multiplate^®, MP). Three different platelet activators were used: adenosine-diphosphate (ADP test), arachidonic acid (ASPI test), and thrombin activated peptide-6 (TRAP test). Blood transfusion requirements within 6 h and 24 h and the association of platelet dysfunction on mortality was investigated. A total of 328 predominantly male patients (75.3%) with a median age of 53 (37–68) years and a median ISS of 29 (22–38) were included. No significant difference between the TBI group, the MT group, and the MT + TBI group was detected for any of the investigated platelet function tests. Unadjusted and adjusted for platelet count, the investigated MP assays revealed no significant group differences upon ER admission and were not able to sufficiently predict massive transfusion, neither within the first 6 h nor for the first 24 h after hospital admission. No association between platelet dysfunction measured by MP upon ER admission and mortality was observed. Conclusion: Injury pattern did not specifically impact platelet function measurable by MP. Platelet dysfunction upon ER admission measurable by MP was not associated with transfusion requirements and mortality. The clinical relevance of platelet function testing by MP in trauma patients not on platelet inhibitors is questionable.

Critical traumatic brain injury is associated with worse coagulopathy

OBJECTIVES

As thromboelastography (TEG) becomes the standard of care in patients with hemorrhagic shock (HS), an association between concomitant traumatic brain injury (TBI) and coagulopathy by TEG parameters is not well understood and is thus investigated.

METHODS

Retrospective analysis of trauma registry data at a single level 1 trauma center of 772 patients admitted with head Abbreviated Injury Scale (AIS) score of 3 and TEG studies between 2014 and 2017. Patients were stratified to moderate-severe TBI by head AIS scores of 3 and 4 (435 patients) and critical TBI by head AIS score of 5 (328 patients). Hemorrhagic shock was defined by base deficit of 4 or shock index of 0.9. Statistical analysis with unpaired t tests compared patients with critical TBI with patients with moderate-severe TBI, and patients were grouped by presence or absence of HS. A comparison of TBI data with conventional coagulation studies was also evaluated.

RESULTS

In the setting of HS, critical TBI versus moderate-severe TBI was associated with longer R time (p = 0.004), longer K time (p < 0.05), less acute angle (p = 0.001), and lower clot strength and stability (maximum amplitude [MA]) (p = 0.01). Worse TBI did not correlate with increased fibrinolysis by clot lysis measured by the percentage decrease in amplitude at 30 minutes after MA (p = 0.3). Prothrombin time and international normalized ratio failed to demonstrate more severe coagulopathy, while partial thromboplastin time was found to correlate with severity of TBI (p = 0.01). In patients with critical TBI, the presence of HS correlated with a statistically significant worsening of all parameters (p < 0.05) except for clot lysis measured by the percentage decrease in amplitude at 30 minutes after MA (LY-30).

CONCLUSION

Thromboelastography demonstrates that, with and without hemorrhagic shock, critical TBI correlates with a significant worsening of traumatic coagulopathy in comparison with moderate/severe TBI. In HS, critical TBI correlates with impaired clot initiation, impaired clot kinetics, and impaired platelet-associated clot strength and stability versus parameters found in moderate-severe TBI. Hemorrhagic shock correlates with worse traumatic coagulopathy in all evaluated patient groups with TBI. Conventional coagulation studies underestimate TBI-associated coagulopathy. Traumatic brain injury-associated coagulopathy is not associated with fibrinolysis.

LEVEL OF EVIDENCE

Prognostic/epidemiological, level IV; prognostic/epidemiological, level III.

Thromboelastography is a Marker for Clinically Significant Progressive Hemorrhagic Injury in Severe Traumatic Brain Injury

BACKGROUND

Coagulopathy in traumatic brain injury (TBI) is associated with increased risk of poor outcomes, but accurate prediction of clinically significant progressive hemorrhagic injury (PHI) in patients with severe TBI remains a challenge. Thromboelastography (TEG) is a real-time test of whole blood coagulation that provides dynamic information about global hemostasis. This study aimed to identify differences in TEG values between patients with severe TBI who did or did not experience clinically significant PHI.

METHODS

This was a single-center retrospective cohort study of adult patients with severe TBI. Patients were eligible for inclusion if initial Glasgow coma scale (GCS) was ≤ 8 and baseline head computed tomography (CT) imaging and TEG were available. Exclusion criteria included receipt of hemostatic agents prior to TEG. PHI was defined as bleeding expansion on CT within 24 h associated with 2-point drop in GCS, neurosurgical intervention, or mortality within 24 h. The primary endpoint was TEG value differences between patients with and without PHI. Secondary endpoints included differences in conventional coagulation tests (CCTs) between groups.

RESULTS

Of the 526 patients evaluated, 141 met inclusion criteria. The most common reason for exclusion was lack of baseline TEG and receipt of reversal product prior to TEG. Sixty-four patients experienced PHI in the first 24 h after presentation. K time (2.03 min vs. 1.33 min, P = 0.035) and alpha angle (65° vs. 69°, P = 0.015) were found to be significantly different in patients experiencing PHI. R time (5.25 min vs. 4.71 min), maximum amplitude (61 mm vs. 63 mm), and clot lysis at 30 min after maximum clot strength (3.5% vs. 1.7%) were not significantly different between groups. Of the CCTs, only activated partial thromboplastin time (30.3 s vs. 27.6 s, P = 0.014) was found to be different in patients with PHI.

CONCLUSIONS

Prolonged K time and narrower alpha angle were found to be associated with developing clinically significant PHI in patients with severe TBI. Despite differences detected in alpha angle, median values in both groups were within normal reference ranges. These abnormalities may reflect pathologic hypoactivity of fibrinogen, and further study is warranted to evaluate TEG-guided cryoprecipitate administration in this patient population.

Injury Severity, Arrival Physiology, Coagulopathy, and Outcomes Among the Youngest Trauma Patients

BACKGROUND

Although physiologic differences exist between younger and older children, pediatric trauma analyses are weighted toward older patients. Trauma-induced coagulopathy, determined by rapid thrombelastography (rTEG), is a predictor of outcome in trauma patients, but the significance of rTEG values among very young trauma patients remains unknown. Our objective was to identify the prehospital or physiologic factors, including rTEG values, that were associated with mortality in trauma patients younger than 5 y old.

MATERIALS AND METHODS

Patients younger than 5 y old that met the highest-level trauma activation criteria at an academic children's hospital from 2010-2016 were included. Data regarding demographics, pre-hospital management, laboratory values, injury severity, and outcome were queried. Univariate and multivariate analyses were performed comparing survivors and non-survivors.

RESULTS

A total of 356 patients were included. 60% were male, and the median age was 3 y (IQR 1-4). Overall mortality was 13% (n = 45); brain injury (91%) and hemorrhage (9%) were the causes of death. Compared to survivors, rTEG values in nonsurvivors showed longer activated clotting time and slower speed of clot formation. Clot strength was also decreased in nonsurvivors. On stepwise regression modeling, rTEG values were not significant predictors of mortality. Admission base deficit, arrival temperature, and head injury severity were identified as independent predictors of mortality.

CONCLUSIONS

While rTEG identified coagulopathy in trauma patients < 5 y old, it was not an independent predictor of mortality. Our findings suggest that trauma providers should pay close attention to admission base deficit, arrival temperature, and head injury severity when managing the youngest trauma patients.

Do all cardiac surgery patients benefit from antifibrinolytic therapy?

BACKGROUND

In trauma patients, the recognition of fibrinolysis phenotypes has led to a re-evaluation of the risks and benefits of antifibrinolytic therapy (AF). Many cardiac patients also receive AF, but the distribution of fibrinolytic phenotypes in that population is unknown. The purpose of this hypothesis-generating study was to fill that gap.

METHODS

Seventy-eight cardiac surgery patients were retrospectively reviewed. Phenotypes were defined as hypofibrinolytic (LY30 <0.8%), physiologic (0.8%-3.0%), and hyperfibrinolytic (>3%) based on thromboelastogram.

RESULTS

The population was 65 ± 10-years old, 74% male, average body mass index of 29 ± 5 kg/m² . Fibrinolytic phenotypes were distributed as physiologic = 45% (35 of 78), hypo = 32% (25 of 78), and hyper = 23% (18 of 78). There was no obvious effect of age, gender, race, or ethnicity on this distribution; 47% received AF. For AF versus no AF, the time with chest tube was longer (4 [1] vs. 3 [1] days, p = .037), and all-cause morbidity was more prevalent (51% vs. 25%, p = .017). However, when these two groups were further stratified by phenotypes, there were within-group differences in the percentage of patients with congestive heart failure (p = .022), valve disease (p = .024), on-pump surgery (p < .0001), estimated blood loss during surgery (p = .015), transfusion requirement (p = .015), and chest tube output (p = .008), which highlight other factors along with AF that might have affected all-cause morbidity.

CONCLUSION

This is the first description of the prevalence of three different fibrinolytic phenotypes and their potential influence on cardiac surgery patients. The use of AF was associated with increased morbidity, but because of the small sample size and treatment allocation bias, additional confirmatory studies are necessary. We hope these present findings open the dialog on whether it is safe to administer AFs to cardiac surgery patients who are normo- or hypofibrinolytic.

Implementation of Thromboelastometry for Coagulation Management in Isolated Traumatic Brain Injury Patients Undergoing Craniotomy

BACKGROUND Coagulopathy (CP) is a modifiable factor linked with secondary brain damage and poor outcome of traumatic brain injury (TBI). A shift towards goal-directed coagulation management has been observed recently. We investigated whether rotational thromboelastometry (ROTEM) based management could be successfully implemented in TBI patients and improve outcomes. MATERIAL AND METHODS A prospective, case-control study was performed. Adult patients with isolated TBI requiring craniotomy were included in this study. All patients underwent standard coagulation tests (SCT). Patients were identified as either in control group or in case group. Patients in the case group were additionally tested with ROTEM to specify their coagulation status. Management of the patients in the control group was based on SCT, whereas management of patients in the case group was guided by ROTEM. Outcome measures were as follows: CP rate, protocol adhesion, blood loss, transfusions, progressive hemorrhagic injury (PHI), re-intervention, Glasgow coma score (GCS) and Glasgow outcome score (GOS) at discharge, and in-hospital mortality. RESULTS There were 134 patients enrolled (65 patients in the control group and 69 patients in the case group). Twenty-six patients in the control group (40%) were found to be coagulopathic (control-CP subgroup) and 34 patients in the case group (49.3%) were found to be coagulopathic (case-CP subgroup). Twenty-five case-CP patients had ROTEM abnormalities triggering protocolized intervention, and 24 of them were treated. Overall ROTEM-based protocol adhesion rate was 85.3%. Postoperative ROTEM parameters of case-CP patients significantly improved, and the number of coagulopathic patients decreased. The incidence of PHI (control versus case group) and neurosurgical re-intervention (control-CP versus case-CP subgroup) was in favor of ROTEM guidance (P<0.05). Mortality and GCS and GOS at discharge did not differ significantly between groups. CONCLUSIONS ROTEM led to consistent coagulation management, improved clot quality, and decreased incidence of PHI and neurosurgical re-intervention. Further studies are needed to confirm benefits of ROTEM in cases of TBI.

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.

Impact of Traumatic Brain Injury on Clinical Institute Withdrawal Assessment Use in Trauma Patients: A Descriptive Study

BACKGROUND

Alcohol withdrawal syndrome (AWS) and traumatic brain injury (TBI) present with similar signs and symptoms, yet their treatment strategies differ greatly. AWS treatment includes the Clinical Institute Withdrawal Assessment (CIWA) protocol, which grades withdrawal signs and symptoms. A major purpose of CIWA is to guide the addition and titration of central nervous system (CNS) depressants, most commonly benzodiazepines. Conversely, best practice is to avoid these same CNS depressants in the setting of TBI. Thus, patients with TBI presenting with AWS risk may receive undesirable interventions that could worsen outcome.

OBJECTIVE

To describe the relationship of TBI diagnosis with CIWA protocol scores and intervention implementation.

DESIGN

Retrospective cohort observational study.

SETTING

Single university-based, level one trauma center.

PATIENTS

Three hundred seventy-five patients with head trauma or AWS classification, identified through the trauma center's trauma registry.

INTERVENTIONS

CIWA protocol and related medication use.

MAIN OUTCOME MEASURES

Frequency of elevated CIWA score, length of CIWA administration, and medication administration incidence were abstracted from patients' medical records.

RESULTS

The percentage of elevated CIWA scores increased significantly with TBI severity, from 4.5%(0-60) in the No TBI group, up to 12.5% (0-36) in the Mild TBI group, 27.1% (0-57) in the Moderate TBI group, and 50.0% (14-77) in the Severe TBI group. Nominally, lorazepam use showed a similar pattern of escalation with TBI severity, but it did not reach statistical significance. Haloperidol use did significantly escalate with higher TBI severity. No group differences were observed for total lorazepam equivalents or length on the CIWA protocol.

CONCLUSIONS

TBI diagnosis and higher TBI severity level correlate with higher CIWA scores, but neither increased nor decreased benzodiazepine usage was observed. Antipsychotic use did escalate with TBI diagnosis and severity. The risks versus benefits of minimizing benzodiazepines in patients with TBI who are at risk for AWS warrant future study.

A new era of thromboelastometry

Severe hemorrhage with necessity of allogeneic blood transfusion is common complication in intensive care unit and is associated with increased morbidity and mortality. Prompt recognition and treatment of bleeding causes becomes essential for the effective control of hemorrhage, rationalizing the use of allogeneic blood components, and in this way, preventing an occurrence of their potential adverse effects. Conventional coagulation tests such as prothrombin time and activated partial thromboplastin time present limitations in predicting bleeding and guiding transfusion therapy in critically ill patients. Viscoelastic tests such as thromboelastography and rotational thromboelastometry allow rapid detection of coagulopathy and goal-directed therapy with specific hemostatic drugs. The new era of thromboelastometry relies on its efficacy, practicality, reproducibility and cost-effectiveness to establish itself as the main diagnostic tool and transfusion guide in patients with severe active bleeding.

Geriatric trauma

PURPOSE OF REVIEW

The landscape of trauma is changing due to an aging population. Geriatric patients represent an increasing number and proportion of trauma admissions and deaths. This review explores recent literature on geriatric trauma, including triage criteria, assessment of frailty, fall-related injury, treatment of head injury complicated by coagulopathy, goals of care, and the need for ongoing education of all surgeons in the care of the elderly.

RECENT FINDINGS

Early identification of high-risk geriatric patients is imperative to initiate early resuscitative efforts. Geriatric patients are typically undertriaged because of their baseline frailty being underappreciated; however, centers that see more geriatric patients do better. Rapid reversal of anticoagulation is important in preventing progression of brain injury. Anticipation of difficult disposition necessitates early involvement of physical therapy for rehabilitation and case management for appropriate placement.

SUMMARY

Optimal care of geriatric trauma patients will be based on the well established tenets of trauma resuscitation and injury repair, but with distinct elements that address the physiological and anatomical challenges presented by geriatric patients.

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.

Normalization of coagulopathy is associated with improved outcome after isolated traumatic brain injury

Acute traumatic coagulopathy (ATC) has been reported in the setting of isolated traumatic brain injury (iTBI) and is associated with poor outcomes. We aimed to evaluate the effectiveness of procoagulant agents administered to patients with ATC and iTBI during resuscitation, hypothesizing that timely normalization of coagulopathy may be associated with a decrease in mortality. A retrospective review of the Alfred Hospital trauma registry, Australia, was conducted and patients with iTBI (head Abbreviated Injury Score [AIS] ⩾3 and all other body AIS <3) and coagulopathy (international normalized ratio ⩾1.3) were selected for analysis. Data on procoagulant agents used (fresh frozen plasma, platelets, cryoprecipitate, prothrombin complex concentrates, tranexamic acid, vitamin K) were extracted. Among patients who had achieved normalization of INR or survived beyond 24hours and were not taking oral anticoagulants, the association of normalization of INR and death at hospital discharge was analyzed using multivariable logistic regression analysis. There were 157 patients with ATC of whom 68 (43.3%) received procoagulant products within 24hours of presentation. The median time to delivery of first products was 182.5 (interquartile range [IQR] 115-375) minutes, and following administration of coagulants, time to normalization of INR was 605 (IQR 274-1146) minutes. Normalization of INR was independently associated with significantly lower mortality (adjusted odds ratio 0.10; 95% confidence interval 0.03-0.38). Normalization of INR was associated with improved mortality in patients with ATC in the setting of iTBI. As there was a substantial time lag between delivery of products and eventual normalization of coagulation, specific management of coagulopathy should be implemented as early as possible.

Acute Fibrinolysis Shutdown after Injury Occurs Frequently and Increases Mortality: A Multicenter Evaluation of 2,540 Severely Injured Patients

BACKGROUND

Fibrinolysis is a physiologic process that maintains microvascular patency by breaking down excessive fibrin clot. Hyperfibrinolysis is associated with a doubling of mortality. Fibrinolysis shutdown, an acute impairment of fibrinolysis, has been recognized as a risk factor for increased mortality. The purpose of this study was to assess the incidence and outcomes of fibrinolysis phenotypes in 2 urban trauma centers.

STUDY DESIGN

Injured patients included in the analysis were admitted between 2010 and 2013, were 18 years of age or older, and had an Injury Severity Score (ISS) > 15. Admission fibrinolysis phenotypes were determined by the clot lysis at 30 minutes (LY30): shutdown ≤ 0.8%, physiologic 0.9% to 2.9%, and hyperfibrinolysis ≥ 3%. Logistic regression was used to adjust for age, arrival blood pressure, ISS, mechanism, and facility.

RESULTS

There were 2,540 patients who met inclusion criteria. Median age was 39 years (interquartile range [IQR] 26 to 55 years) and median ISS was 25 (IQR 20 to 33), with a mortality rate of 21%. Fibrinolysis shutdown was the most common phenotype (46%) followed by physiologic (36%) and hyperfibrinolysis (18%). Hyperfibrinolysis was associated with the highest death rate (34%), followed by shutdown (22%), and physiologic (14%, p < 0.001). The risk of mortality remained increased for hyperfibrinolysis (odds ratio [OR] 3.3, 95% CI 2.4 to 4.6, p < 0.0001) and shutdown (OR 1.6, 95% CI 1.3 to 2.1, p = 0.0003) compared with physiologic when adjusting for age, ISS, mechanism, head injury, and blood pressure (area under the receiver operating characteristics curve 0.82, 95% CI 0.80 to 0.84).

CONCLUSIONS

Fibrinolysis shutdown is the most common phenotype on admission and is associated with increased mortality. These data provide additional evidence of distinct phenotypes of coagulation impairment and that individualized hemostatic therapy may be required.

Fibrinogen and base excess levels as predictive markers of the need for massive blood transfusion after blunt trauma

Background

Assessment blood consumption and trauma-associated severe hemorrhage scores are useful for predicting the need for massive transfusion (MT) in severe trauma patients. However, fibrinogen (Fbg) and base excess (BE) levels might also be useful indicators for the need for MT. We evaluated the accuracy of prediction for MT of the scoring system vs. Fbg and BE.

Methods

The subjects of this retrospective single center observational study were patients with injury severity score ≥16 trauma, divided into a non-MT group and an MT group. We compared variables, including the scoring system (comprising vital signs and focused assessment with sonography for trauma; FAST) and Fbg between the groups. We then performed a multiple logistic regression modeling and a receiver operating characteristic analysis to clarify which value was the most useful predictive indicator for MT.

Results

There were 114 patients in the non-MT group and 39 in the MT group. The level of Fbg and BE were independent predictors of MT. The area under the curve values for Fbg and BE were 0.765 and 0.845, respectively, and the optimal cutoff values of Fbg and BE were 211 mg/dL and −1.4, respectively.

Conclusions

Fbg and BE levels can be used as an independent predictor for MT.

A meta-analysis to determine the effect of coagulopathy on intracranial haematoma progression in adult patients with isolated blunt head trauma

Coagulopathy following isolated traumatic brain injury is a well-recognised complication especially in patients with severe head injury. Intracranial haematoma progression is a major adverse factor affecting outcome in patients with traumatic brain injury. Coagulopathy is an important risk factor for haematoma progression. The aim of this meta-analysis was to determine the magnitude of effect of coagulopathy on intracranial haematoma progression in patients with isolated traumatic brain injury. Studies comparing patients with traumatic brain injury, coagulopathy and haematoma progression to patients with traumatic brain injury, haematoma progression and no coagulopathy were identified. The search was performed using Medline via the PubMed interface; no limits were placed on the language. In total 12 studies were identified as being suitable for the meta-analysis. Significant heterogeneity was present between the studies as demonstrated by an I2 = 80.185. The fixed effects model was considered to be the preferred model and this produced a pooled odds ratio of 6.897 (95% confidence interval: 5.495–8.655). The results of this meta-analysis show that traumatic brain injury-induced coagulopathy is a significant factor in haematoma progression in patients with isolated traumatic brain injury.

Predicting progressive hemorrhagic injury from isolated traumatic brain injury and coagulation

BACKGROUND

Progressive hemorrhagic injury (PHI) in traumatic brain injury (TBI) patients is associated with poor outcomes. Early prediction of PHI is difficult yet vital. We hypothesize that TBI subtype and coagulation would be predictors of PHI.

METHODS

This was a retrospective analysis of highest level activation adult trauma patients with evidence of TBI (head Abbreviated Injury Scale ≥3). Coagulopathy was determined using rapid thrombelastography (r-TEG), complete blood counts, and conventional coagulation tests obtained on arrival. Patients were dichotomized into PHI and stable groups based on head computerized CT. Subtypes of TBI included subdural hematoma, intraparenchymal contusions (IPC), subarachnoid hemorrhage, epidural hematoma, and combined. Data are reported as median values with interquartile range (IQR). Multivariate logistic regression was used to assess the effect of subtype and coagulation on PHI.

RESULTS

We included 279 isolated TBI patients who met study criteria. There were 157 patients (56%) who experienced PHI; 122 (44%) were stable on repeat CT. Patients with PHI were older, had fewer hospital-free days, and higher mortality (all P < .001). No differences were noted in r-TEG parameters between groups; however, coagulopathy and age were independent predictors of progression in all subtypes (odds ratio [OR], 1.81; 95% CI, 1.09-3.01 [P = .021]; OR, 1.02, 95% CI, 1.01-1.04 [P = .006]). Controlling for age, Glasgow Coma Scale score, and coagulopathy, patients with IPC were more likely to experience PHI (OR, 4.49; 95% CI, 2.24-8.98; P < .0001).

CONCLUSION

This study demonstrates that older patients with coagulation abnormalities and IPC on admission are more likely to experience PHI, identifying a target population for earlier therapies.

Brain-derived microparticles induce systemic coagulation in a murine model of traumatic brain injury

Traumatic brain injury (TBI) is associated with coagulopathy, although it often lacks 2 key risk factors: severe bleeding and significant fluid resuscitation associated with hemorrhagic shock. The pathogenesis of TBI-associated coagulopathy remains poorly understood. We tested the hypothesis that brain-derived microparticles (BDMPs) released from an injured brain induce a hypercoagulable state that rapidly turns into consumptive coagulopathy. Here, we report that mice subjected to fluid percussion injury (1.9 ± 0.1 atm) developed a BDMP-dependent hypercoagulable state, with peak levels of plasma glial cell and neuronal BDMPs reaching 17 496 ± 4833/μL and 18 388 ± 3657/μL 3 hours after TBI, respectively. Uninjured mice injected with BDMPs developed a dose-dependent hyper-turned hypocoagulable state measured by a progressively prolonged clotting time, fibrinogen depletion, and microvascular fibrin deposition in multiple organs. The BDMPs were 50 to 300 nm with intact membranes, expressing neuronal or glial cell markers and procoagulant phosphatidylserine and tissue factor. Their procoagulant activity was greater than platelet microparticles and was dose-dependently blocked by lactadherin. Microparticles were produced from injured hippocampal cells, transmigrated through the disrupted endothelial barrier in a platelet-dependent manner, and activated platelets. These data define a novel mechanism of TBI-associated coagulopathy in mice, identify early predictive markers, and provide alternative therapeutic targets.