Abstract Coagulopathy and thrombosis associated with coronavirus disease 2019 (COVID-19) represent a major issue in the management of this disease. In the past months, clinical studies have demonstrated that COVID-19 patients present with a particular hypercoagulable state, in which a markedly increased D-dimer concomitant with increased levels of fibrinogen are observed. This hypercoagulable state leads to an increased risk of thrombosis, which seems to be higher among those patients with critical symptoms of COVID-19. The best therapeutic approach to prevent thrombotic events in COVID-19 has not been determined yet and several questions regarding thromboprophylaxis therapy, such as the time to initiate anticoagulation, type of anticoagulant and dose regimen, have emerged among physicians. To address these concerns, several medical societies have published position papers to provide the opinion of thrombosis experts on the management of coagulopathy and thrombosis associated with COVID-19. In line with this, the Latin America Cooperative Group of Hemostasis and Thrombosis (Grupo CLAHT) has constituted a panel of experts in thrombosis and hemostasis to discuss the available data on this topic. The aim of this review is to summarize the current evidence regarding hemostatic impairment and thrombotic risk in COVID-19 and to provide a carefully revised opinion of Latin American experts on the thromboprophylaxis and management of thrombotic events and coagulopathy in patients with suspected COVID-19.

Resumen La coagulopatía y la trombosis asociadas a la enfermedad por coronavirus 2019 (COVID-19) representan un problema importante en el manejo de esta enfermedad. Los estudios clínicos de los últimos meses han demostrado que los pacientes con COVID-19 presentan un estado de hipercoagulabilidad particular, en el que se observa un aumento notable del dímero D concomitante con niveles elevados de fibrinógeno. El estado de hipercoagulabilidad conduce a un mayor riesgo de trombosis, que parece ser mayor entre aquellos pacientes con síntomas críticos de COVID-19. El mejor enfoque terapéutico para prevenir los eventos trombóticos en esta nueva enfermedad aún no se ha determinado y han surgido varias preguntas con respecto a la tromboprofilaxia, como el momento adecuado para iniciar la anticoagulación, el tipo de anticoagulante y el régimen de dosis. Para abordar estas preocupaciones, varias sociedades médicas han publicado artículos de posición para brindar la opinión de expertos en trombosis sobre el manejo de la coagulopatía y trombosis asociadas a COVID-19. El Grupo Cooperativo Latinoamericano de Hemostasia y Trombosis (Grupo CLAHT) ha convocado a un panel de expertos en trombosis y hemostasia para discutir los datos disponibles sobre este tema. El objetivo de esta revisión es resumir la evidencia actual con respecto al deterioro hemostático y el riesgo trombótico en el COVID-19 y proporcionar una opinión cuidadosamente revisada de los expertos latinoamericanos sobre la tromboprofilaxis y el manejo de eventos trombóticos y coagulopatía en pacientes con sospecha de COVID-19.

ABSTRACT Hemostatic abnormalities and thrombotic risk associated with coronavirus disease 2019 (COVID-19) are among the most discussed topics in the management of this disease. The aim of this position paper is to provide the opinion of Brazilian experts on the thromboprophylaxis and management of thrombotic events in patients with suspected COVID-19, in the sphere of healthcare in Brazil. To do so, the Brazilian Society of Thrombosis and Hemostasis (BSTH) and the Thrombosis and Hemostasis Committee of the Brazilian Association of Hematology, Hemotherapy and Cellular Therapy (ABHH) have constituted a panel of experts to carefully review and discuss the available evidence about this topic. The data discussed in this document was reviewed by May 9, 2020. Recommendations and suggestions reflect the opinion of the panel and should be reviewed periodically as new evidence emerges.