Thrombelastography and tromboelastometry in assessing coagulopathy in trauma

Abstract

Death due to trauma is the leading cause of lost life years worldwide, with haemorrhage being responsible for 30-40% of trauma mortality and accounting for almost 50% of the deaths the initial 24 h. On admission, 25-35% of trauma patients present with coagulopathy, which is associated with a several-fold increase in morbidity and mortality. The recent introduction of haemostatic control resuscitation along with emerging understanding of acute post-traumatic coagulability, are important means to improve therapy and outcome in exsanguinating trauma patients. This change in therapy has emphasized the urgent need for adequate haemostatic assays to monitor traumatic coagulopathy and guide therapy. Based on the cell-based model of haemostasis, there is emerging consensus that plasma-based routine coagulation tests (RCoT), like prothrombin time (PT) and activated partial thromboplastin time (APTT), are inappropriate for monitoring coagulopathy and guide therapy in trauma. The necessity to analyze whole blood to accurately identify relevant coagulopathies, has led to a revival of the interest in viscoelastic haemostatic assays (VHA) such as Thromboelastography (TEG®) and Rotation Thromboelastometry (ROTEM®). Clinical studies including about 5000 surgical and/or trauma patients have reported on the benefit of using the VHA as compared to plasma-based assays, to identify coagulopathy and guide therapy.This article reviews the basic principles of VHA, the correlation between the VHA whole blood clot formation in accordance with the cell-based model of haemostasis, the current use of VHA-guided therapy in trauma and massive transfusion (haemostatic control resuscitation), limitations of VHA and future perspectives of this assay in trauma.

How I treat patients with massive hemorrhage

“…The trace is divided into parts that reflect different stages of the hemostatic process (clotting time, kinetics, strength, and lysis) with slightly different nomenclature for TEG and ROTEM. 22 BLOOD 58 This is in alignment with the findings of the Prospective, Observational, Multicenter, Major Trauma Transfusion (PROMMTT) study reporting that early balanced plasma was associated with decreased 6-hour mortality, whereas this was not the case for receiving delayed but gradually balanced transfusion ratios. 59,60 This notion was further corroborated by Rawdan and colleagues, who reported that moving thawed plasma from the blood bank to the emergency department, enabling early balanced blood product transfusion, was associated with a reduction in overall blood product use and a 60% decrease in odds of 30-day mortality.…”

“…These studies demonstrate superiority of VHA to monitor and guide hemostatic resuscitation compared with conventional coagulation tests, resulting in reduced transfusion requirements, need for re-do surgery, and mortality. 22,23 Furthermore, The Scientific and Standardization Committee of the International Society on Thrombosis and Haemostasis recommended in 2013 the use of VHA-guided hemostatic therapy also in actively bleeding patients with hemophilia. 24 It should be noted that the standard VHA tests, TEG and ROTEM, cannot measure pharmacological platelet inhibition and thus identify bleeding secondary to aspirin and/or adenosine 59-diphosphate receptor inhibitors such as clopidogrel, effient, or ticagrelor.…”

The simultaneous occurrence of both hypercoagulability and hypofibrinolysis in blood and serum during systemic inflammation, and the roles of iron and fibrin(ogen)

“…We show how this provides insight into hypofibrinolysis associated with inflammation (6) and how fibrinogen packaging (7) is changed during inflammation. Here we also discuss various substances and molecules (8) that may influence clot structure and also the relationship between hypercoagulability and fibrosis (9 106,109,[112][113][114][120][121][122][123][124] to the effect that results can be reasonably comparable in some circumstances but for detailed studies of specific effects it is probably wise to standardise on a particular instrument or technique.…”

Evidence Supporting the Use of Recombinant Activated Factor VII in Congenital Bleeding Disorders

“…[51][52][53][54][60][61][62][63][64][65][66][67][68][69][70][71] The scientific rationale for this superiority was delineated by Rivard et al,72 who demonstrated a correlation between total thrombus generation over a period of time, as evaluated by TEG, and the concentration of generated thrombin-antithrombin complexes. Coagulation-factor deficiency and/or t hrombocytopenia/pathy likely results in impaired thrombin generation, thus reducing the clot formation and stability, which is indicated by an abnormal TEG tracing.…”