The Choice between Plasma-Based Common Coagulation Tests and Cell-Based Viscoelastic Tests in Monitoring Hemostatic Competence: Not an either-or Proposition.

There has been a significant interest in the last decade in the use of viscoelastic tests (VETs) to determine the hemostatic competence of bleeding patients. Previously, common coagulation tests (CCTs) such as the prothrombin time (PT) and partial thromboplastin time (PTT) were used to assist in the guidance of blood component and hemostatic adjunctive therapy for these patients. However, the experience of decades of VET use in liver failure with transplantation, cardiac surgery, and trauma has now spread to obstetrical hemorrhage and congenital and acquired coagulopathies. Since CCTs measure only 5 to 10% of the lifespan of a clot, these assays have been found to be of limited use for acute surgical and medical conditions, whereby rapid results are required. However, there are medical indications for the PT/PTT that cannot be supplanted by VETs. Therefore, the choice of whether to use a CCT or a VET to guide blood component therapy or hemostatic adjunctive therapy may often require consideration of both methodologies. In this review, we provide examples of the relative indications for CCTs and VETs in monitoring hemostatic competence of bleeding patients.

A Case Series of Thromboelastography-Guided Anticoagulation in COVID-19 Patients with Inherited and Acquired Hypercoagulable States.

One of the complications of the novel coronavirus disease 2019 (COVID-19) is hypercoagulability. For this reason, patients presenting with COVID-19 are often put on therapeutic or intermediate anticoagulation upon hospitalization. A common issue of this anticoagulation is the progression to hypocoagulability resulting in hemorrhage. Therefore, monitoring the hemostatic integrity of critically ill COVID-19 patients is of utmost importance. In this case series, we present the cases of three coagulopathic COVID-19 patients whose anticoagulation was guided by thromboelastography (TEG). In each case, TEG permitted the clinical team to simultaneously prevent thrombotic and hemorrhagic events, a difficult task for COVID-19 patients admitted to the intensive care unit. The first two cases illustrate the utility of TEG to guide anticoagulant dosing for COVID-19 patients when the activated partial thromboplastin time (aPTT) is inaccurate. The first case was a severely ill COVID-19 patient with end-stage renal disease and a falsely elevated aPTT secondary to hypertriglyceridemia. The second case was a severely ill COVID-19 patient with chronic pulmonary disease who demonstrated a falsely elevated aPTT due to polycythemia and hemoconcentration. In both cases, TEG was sensitive to the hypercoagulability caused by the metabolic derangements which enabled the goal-directed titration of anticoagulants. The last case depicts a severely ill COVID-19 patient with an inherited factor V Leiden mutation who required abnormally high dosing to achieve therapeutic anticoagulation, guided by TEG. Hypercoagulopathic COVID-19 patients are difficult to anticoagulate without development of hypocoagulopathy. Treatment of these patients demands goal-directed therapy by diligent laboratory monitoring. This can be accomplished by the use of TEG coupled with aPTT to guide anticoagulation. This case series illustrates the necessity for active hemostatic monitoring of critically ill COVID-19 patients.

Thromboelastography-Guided Anticoagulant Therapy for the Double Hazard of Thrombohemorrhagic Events in COVID-19: A Report of 3 Cases.

BACKGROUND The novel coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), often manifests a coagulopathy in severely ill patients, which may cause hemorrhage and/or thrombosis of varying severity. This report comprises the cases of 3 patients with COVID-19-associated coagulopathy who were evaluated with thromboelastography (TEG) and activated partial thromboplastin time (aPTT) to enable personalized anticoagulant therapy. CASE REPORT Three patients presented with COVID-19 pneumonia, confirmed by reverse transcription-polymerase chain reaction, who developed thrombohemorrhagic coagulopathy.Case 1: A 72-year-old woman on long-term warfarin therapy for a history of venous thromboembolism developed a right upper lobe pulmonary embolus, despite an international normalized ratio of 6.4 and aPTT of 120.7 s. TEG enabled successful anticoagulation with heparin, and her pulmonary infarct was no longer present 2 weeks later.Case 2: A 55-year-old woman developed a rectus sheath hematoma while on heparin, and TEG demonstrated increased fibrinolysis despite COVID-19 patients more commonly undergoing fibrinolytic shutdown.Case 3: A 43-year-old woman had significant thrombus burden while severely hypocoagulable according to laboratory testing. As the venous thrombi enlarged in a disseminated intravascular coagulopathic-like state, the heparin dose was escalated to achieve a target aPTT of 70 to 80 s, resulting in a flat line TEG tracing. CONCLUSIONS These 3 cases of COVID-19 pneumonia with complex and varied clinical histories demonstrated the clinical value of TEG combined with the measurement of aPTT to facilitate personalized anticoagulation, resulting in good clinical outcomes.

Impact of a clinical pharmacist on ultrasound-guided venous thromboembolism screening in hospitalized COVID-19 patients: a pilot prospective study.

BACKGROUND: The recognition, prevention and treatment of venous thromboembolism (VTE) remains a major challenge in the face of the recent COVID-19 pandemic which has been associated with significant cardiovascular, renal, respiratory and hematologic complications related to hypercoagulability. There has been little literature thus far on the utility of screening ultrasound and the role of the clinical pharmacist in treating these patients. METHODS: We present a prospective pilot program of thirty-one consecutive COVID-19 patients who were provided four extremity screening ultrasounds for VTE on admission. This was coordinated by a clinical pharmacist as part of a multidisciplinary approach. Quantitative and qualitative data were recorded with the goal of describing the utility of the clinical pharmacist in ultrasound screening. Data collected include demographics, information on clinical symptoms or signs at presentation, and laboratory and radiologic results during the hospitalization from each individual electronic medical record. RESULTS: Nine of the thirty-one patients presented with VTE. Of the nine patients, there were twenty-two total clotted vessels, all of which were asymptomatic. The clinical pharmacist, as the coordinator for a multidisciplinary COVID-19 associated coagulopathy management team, drafted a screening and treatment protocol for anticoagulation prophylaxis and therapy of VTE after ultrasound findings. CONCLUSION: VTE screening of hospitalized COVID-19 patients reveals a significant number of asymptomatic VTEs and justifies diagnostic, prophylactic, and treatment measures coordinated by a clinical pharmacist.