Utility of Thromboelastography and velocity curve derivative in diagnosing COVID-19 associated coagulopathy.

BACKGROUND: COVID-19 associated coagulopathy (CAC) can either be localized or systemic hypercoagulable state with increased risk of thromboembolism. This study looked into the usefulness of Thromboelastography (TEG) and the velocity curve (V-curve) derivative from TEG in diagnosing and differentiating different stages of CAC. MATERIALS AND METHODS: A prospective single cohort study of RT-PCR confirmed COVID-19 patients was carried out for 2 weeks. Severe COVID-19 patients in the adult critical care units with a TEG report were recruited for the study. Citrated kaolin TEG was performed on the day of admission before anticoagulation. TEG parameters included were R and K time, alpha angle, maximum amplitude, clotting index, lysis at 30 min. The first-degree velocity curve of TEG is plotted as V-curve which extrapolates thrombus generation potential. Parameters analyzed were the maximum rate of thrombus generation as well as thrombus generated (TG). RESULTS: The study included 43 patients with an average age of 58.34 (±15.35). TEG as well as V-curve of all the patients were hypercoagulable compared with age-matched reference range. We had 79.06% of patients in hypercoagulable stage. The mortality rate was 32.56% and 30.23% developed thrombotic incidents. Patients who succumbed to death had prolonged PT, aPTT, MA, Ly30, with a reduced TG (p < .05). The presence of fibrinolysis was associated with thromboembolism (OR = 6.76, CI = 1.48-25.82). Repeat TEG was done randomly in 11 patients and revealed a persistent hypercoagulable stage with increasing fibrinolysis activity. CONCLUSION: TEG is a useful tool in diagnosing and categorizing Coagulopathy associated with COVID-19.

Coagulation Disorders in Sepsis and COVID-19-Two Sides of the Same Coin? A Review of Inflammation-Coagulation Crosstalk in Bacterial Sepsis and COVID-19.

Sepsis is a major cause of morbidity and mortality worldwide. Sepsis-associated coagulation disorders are involved in the pathogenesis of multiorgan failure and lead to a subsequently worsening prognosis. Alongside the global impact of the COVID-19 pandemic, a great number of research papers have focused on SARS-CoV-2 pathogenesis and treatment. Significant progress has been made in this regard and coagulation disturbances were once again found to underlie some of the most serious adverse outcomes of SARS-CoV-2 infection, such as acute lung injury and multiorgan dysfunction. In the attempt of untangling the mechanisms behind COVID-19-associated coagulopathy (CAC), a series of similarities with sepsis-induced coagulopathy (SIC) became apparent. Whether they are, in fact, the same disease has not been established yet. The clinical picture of CAC shows the unique feature of an initial phase of intravascular coagulation confined to the respiratory system. Only later on, patients can develop a clinically significant form of systemic coagulopathy, possibly with a consumptive pattern, but, unlike SIC, it is not a key feature. Deepening our understanding of CAC pathogenesis has to remain a major goal for the research community, in order to design and validate accurate definitions and classification criteria.

The procoagulant pattern of patients with COVID-19 acute respiratory distress syndrome.

BACKGROUND: Few observations exist with respect to the pro-coagulant profile of patients with COVID-19 acute respiratory distress syndrome (ARDS). Reports of thromboembolic complications are scarce but suggestive for a clinical relevance of the problem. OBJECTIVES: Prospective observational study aimed to characterize the coagulation profile of COVID-19 ARDS patients with standard and viscoelastic coagulation tests and to evaluate their changes after establishment of an aggressive thromboprophylaxis. METHODS: Sixteen patients with COVID-19 ARDS received a complete coagulation profile at the admission in the intensive care unit. Ten patients were followed in the subsequent 7 days, after increasing the dose of low molecular weight heparin, antithrombin levels correction, and clopidogrel in selected cases. RESULTS: At baseline, the patients showed a pro-coagulant profile characterized by an increased clot strength (CS, median 55 hPa, 95% interquartile range 35-63), platelet contribution to CS (PCS, 43 hPa; interquartile range 24-45), fibrinogen contribution to CS (FCS, 12 hPa; interquartile range 6-13.5) elevated D-dimer levels (5.5 µg/mL, interquartile range 2.5-6.5), and hyperfibrinogenemia (794 mg/dL, interquartile range 583-933). Fibrinogen levels were associated (R2  = .506, P = .003) with interleukin-6 values. After increasing the thromboprophylaxis, there was a significant (P = .001) time-related decrease of fibrinogen levels, D-dimers (P = .017), CS (P = .013), PCS (P = .035), and FCS (P = .038). CONCLUSION: The pro-coagulant pattern of these patients may justify the clinical reports of thromboembolic complications (pulmonary embolism) during the course of the disease. Further studies are needed to assess the best prophylaxis and treatment of this condition.

Questions about COVID-19 associated coagulopathy: possible answers from the viscoelastic tests.

Abnormal coagulation parameters are often observed in patients with coronavirus disease 2019 (COVID-19) and the severity of derangement has been associated with a poor prognosis. The COVID-19 associated coagulopathy (CAC) displays unique features that include a high risk of developing thromboembolic complications. Viscoelastic tests (VETs), such as thromboelastometry (ROTEM), thromboelastography (TEG) and Quantra Hemostasis Analyzer (Quantra), provide "dynamic" data on clot formation and dissolution; they are used in different critical care settings, both in hemorrhagic and in thrombotic conditions. In patients with severe COVID-19 infection VETs can supply to clinicians more information about the CAC, identifying the presence of hypercoagulable and hypofibrinolysis states. In the last year, many studies have proposed to explain the underlying characteristics of CAC; however, there remain many unanswered questions. We tried to address some of the important queries about CAC through VETs analysis.

Management of the thrombotic risk associated with COVID-19: guidance for the hemostasis laboratory.

Coronavirus disease 2019 (COVID-19) is associated with extreme inflammatory response, disordered hemostasis and high thrombotic risk. A high incidence of thromboembolic events has been reported despite thromboprophylaxis, raising the question of a more effective anticoagulation. First-line hemostasis tests such as activated partial thromboplastin time, prothrombin time, fibrinogen and D-dimers are proposed for assessing thrombotic risk and monitoring hemostasis, but are vulnerable to many drawbacks affecting their reliability and clinical relevance. Specialized hemostasis-related tests (soluble fibrin complexes, tests assessing fibrinolytic capacity, viscoelastic tests, thrombin generation) may have an interest to assess the thrombotic risk associated with COVID-19. Another challenge for the hemostasis laboratory is the monitoring of heparin treatment, especially unfractionated heparin in the setting of an extreme inflammatory response. This review aimed at evaluating the role of hemostasis tests in the management of COVID-19 and discussing their main limitations.