Trauma-induced coagulopathy: Mechanisms and clinical management.

Introduction: Trauma-induced coagulopathy (TIC) is a form of coagulopathy unique to trauma patients and is associated with increased mortality. The complexity and incomplete understanding of TIC have resulted in controversies regarding optimum management. This review aims to summarise the pathophysiology of TIC and appraise established and emerging advances in the management of TIC.

Methods: This narrative review is based on a literature search (MEDLINE database) completed in October 2020. Search terms used were "trauma induced coagulopathy", "coagulopathy of trauma", "trauma induced coagulopathy pathophysiology", "massive transfusion trauma induced coagulopathy", "viscoelastic assay trauma induced coagulopathy", "goal directed trauma induced coagulopathy and "fibrinogen trauma induced coagulopathy'.

Results: TIC is not a uniform phenotype but a spectrum ranging from thrombotic to bleeding phenotypes. Evidence for the management of TIC with tranexamic acid, massive transfusion protocols, viscoelastic haemostatic assays (VHAs), and coagulation factor and fibrinogen concentrates were evaluated. Although most trauma centres utilise fixed-ratio massive transfusion protocols, the "ideal" transfusion ratio of blood to blood products is still debated. While more centres are using VHAs to guide blood product replacement, there is no agreed VHA-based transfusion strategy. The use of VHA to quantify the functional contributions of individual components of coagulation may permit targeted treatment of TIC but remains controversial.

Conclusion: A greater understanding of TIC, advances in point-of-care coagulation testing, and availability of coagulation factors and fibrinogen concentrates allows clinicians to employ a more goal-directed approach. Still, hospitals need to tailor their approaches according to available resources, provide training and establish local guidelines.