Proteomics of Coagulopathy Following Injury Reveals Limitations of Using Laboratory Assessment to Define Trauma-Induced Coagulopathy to Predict Massive Transfusion

Injury induced endotheliopathy: overview, diagnosis, and management

PURPOSE OF REVIEW

This review aims to examine recent advances in the understanding of injury-induced endotheliopathy and therapeutics to mitigate its development in critically injured patients.

RECENT FINDINGS

Clinical studies have clearly demonstrated that syndecan-1 ectodomains can be found in circulation after various types of trauma and injury and correlates with worse outcomes. As the mechanisms of endotheliopathy are better understood, pathologic hyperadhesive forms of von Willebrand factor, along with a relative deficiency of its cleaving enzyme, a disintegrin and metalloprotease with thrombospondin type I motifs, member 13 (ADAMTS13), have emerged as additional biomarkers. Therapeutics to date have focused primarily on the protective effects of fresh frozen plasma and its constituents to restore the glycocalyx. Human recombinant ADAMTS13 holds promise, as do synthetic variants of heparan sulfate and activated protein C, although all data to date are preclinical.

SUMMARY

Injury-induced endotheliopathy represents an important pathologic response to trauma. Key biomarkers, such as syndecan-1, can aid in the diagnosis, but testing is not yet available clinically. As the mechanisms of endotheliopathy are better understood, therapeutics are being identified and show promise. To date, plasma has been the most widely studied; however, like all therapeutics for injury-induced endotheliopathy, it has primarily been studied in the preclinical setting.

TRAUMA-INDUCED COAGULOPATHY: PREVALENCE AND ASSOCIATION WITH MORTALITY PERSIST 20 YEARS LATER

ABSTRACT

Introduction: A 2003 landmark study identified the prevalence of early trauma-induced coagulopathy (eTIC) at 28% with a strong association with mortality of 8.9%. Over the last 20 years, there have been significant advances in both the fundamental understanding of eTIC and therapeutic interventions. Methods: A retrospective cohort study was performed from 2018 to 2022 on patients ≥18 using prospectively collected data from two level 1 trauma centers and compared to data from 2003. Demographics, laboratory data, and clinical outcomes were obtained. Results: There were 20,107 patients meeting criteria: 65% male, 85% blunt, mean age 54 ± 21 years, median Injury Severity Score 10 (10, 18), 8% of patients were hypotensive on arrival, with an all-cause mortality 6.0%. The prevalence of eTIC remained high at 32% in patients with an abnormal prothrombin time and 10% with an abnormal partial thromboplastin time, for an overall combined prevalence of 33.4%. Coagulopathy had a major impact on mortality over all injury severity ranges, with the greatest impact with lower Injury Severity Score. In a hybrid logistic regression/Classification and Regression Trees analysis, coagulopathy was independently associated with a 2.1-fold increased risk of mortality (95% confidence interval 1.5-2.9); the predictive quality of the model was excellent [area under the receiver operating characteristic curve (AUROC) 0.932]. Conclusion: The presence of eTIC conferred a higher risk of death across all disease severities and was independently associated with a greater risk of death. Biomarkers of coagulopathy associated with eTIC remain strongly predictive of poor outcome despite advances in trauma care.

The pathophysiology of pelvic ring injuries: a review

Traumatic pelvic ring injuries continue to represent a major challenge due to the high rates of post-injury mortality of around 30-40% in the peer-reviewed literature. The main root cause of potentially preventable mortality relates to the delayed recognition of the extent of retroperitoneal hemorrhage and post-injury coagulopathy. The understanding of the underlying pathophysiology of pelvic trauma is predicated by classification systems for grading of injury mechanism and risk stratification for developing post-injury coagulopathy with subsequent uncontrolled exsanguinating hemorrhage. This review article elaborates on the current understanding of the pathophysiology of severe pelvic trauma with a focus on the underlying mechanisms of retroperitoneal bleeding and associated adverse outcomes.

Rapid clearing CT-001 restored hemostasis in mice with coagulopathy induced by activated protein C

BACKGROUND

Activated protein C (APC) is one of the mechanisms contributing to coagulopathy, which is associated with high mortality. The counteraction of the APC pathway could help ameliorate bleeding. However, patients also transform frequently from a hemorrhagic state to a prothrombotic state at a later time. Therefore, a prohemostatic therapeutic intervention should take this thrombotic risk into consideration.

OBJECTIVES

CT-001 is a novel factor VIIa (FVIIa) with enhanced activity and desialylated N-glycans for rapid clearance. We assessed CT-001 clearance in multiple species and its ability to reverse APC-mediated coagulopathic blood loss.

METHODS

The N-glycans on CT-001 were characterized by liquid chromatography-mass spectrometry. Three species were used to evaluate the pharmacokinetics of the molecule. The potency and efficacy of CT-001 under APC pathway-induced coagulopathic conditions were assessed by coagulation assays and bleeding models.

RESULTS

The N-glycosylation sites of CT-001 had high occupancy of desialylated N-glycans. CT-001 exhibited 5 to 16 times higher plasma clearance in human tissue factor knockin mice, rats, and cynomolgus monkeys than wildtype FVIIa. CT-001 corrected the activated partial thromboplastin time and thrombin generation of coagulopathic plasma to normal in in vitro studies. In an APC-mediated saphenous vein bleeding model, 3 mg/kg of CT-001 reduced bleeding time in comparison with wildtype FVIIa. The correction of bleeding by CT-001 was also observed in a coagulopathic tail amputation severe hemorrhage mouse model. The efficacy of CT-001 is independent of the presence of tranexamic acid, and the combination of CT-001 and tranexamic acid does not lead to increased thrombogenicity.

CONCLUSION

CT-001 corrected APC pathway-mediated coagulopathic conditions in preclinical studies and could be a potentially safe and effective procoagulant agent for addressing APC-mediated bleeding.

Omics markers of platelet transfusion in trauma patients

BACKGROUND

Even in the era of the COVID-19 pandemic, trauma remains the global leading cause of mortality under the age of 49. Trauma-induced coagulopathy is a leading driver of early mortality in critically ill patients, and transfusion of platelet products is a life-saving intervention to restore hemostasis in the bleeding patient. However, despite extensive functional studies based on viscoelastic assays, limited information is available about the impact of platelet transfusion on the circulating molecular signatures in trauma patients receiving platelet transfusion.

MATERIALS AND METHODS

To bridge this gap, we leveraged metabolomics and proteomics approaches to characterize longitudinal plasma samples (n = 118; up to 11 time points; total samples: 759) from trauma patients enrolled in the Control Of Major Bleeding After Trauma (COMBAT) study. Samples were collected in the field, in the emergency department (ED), and at intervals up to 168 h (7 days) post-hospitalization. Transfusion of platelet (PLT) products was performed (n = 30; total samples: 250) in the ED through 24 h post-hospitalization. Longitudinal plasma samples were subjected to mass spectrometry-based metabolomics and proteomics workflows. Multivariate analyses were performed to determine omics markers of transfusion of one, two, three, or more PLT transfusions.

RESULTS

Higher levels of tranexamic acid (TXA), inflammatory proteins, carnitines, and polyamines were detected in patients requiring PLT transfusion. Correlation of PLT units with omics data suggested sicker patients required more units and partially overlap with the population requiring transfusion of packed red blood cell products. Furthermore, platelet activation was likely increased in the most severely injured patients. Fatty acid levels were significantly lower in PLT transfusion recipients (at time of maximal transfusion: Hour 4) compared with non-recipients, while carnitine levels were significantly higher. Fatty acid levels restore later in the time course (e.g., post-PLT transfusion).

DISCUSSION

The present study provides the first multi-omics characterization of platelet transfusion efficacy in a clinically relevant cohort of trauma patients. Physiological alterations following transfusion were detected, highlighting the efficacy of mass spectrometry-based omics techniques to improve personalized transfusion medicine. More specialized clinical research studies focused on PLT transfusion, including organized pre and post transfusion sample collection and limitation to PLT products only, are required to fully understand subsequent metabolomic and proteomic alterations.