摘要
Hypercoagulability associated with COVID-19 infection increases risks for either venous or arterial thrombotic events(ATEs)or both.1 For hospitalised patients with COVID-19,the incidence of venous thromboembolism(VTE)was 4.5%2;the rate among patients with crit-ical illness was 27.9%as compared with those not critically ill(7.1%).The exact mechanism of COVID-19-related thrombotic events is unclear.However,it may partially be related to Virchow triad:alternation of blood flow(stasis),vascular endothelial injury by SARS-CoV 2 virus and alteration of the constituents of the blood including inherited or acquired hypercoagulable state.Therefore,it is a challenge to evaluate the thromboembolic risk,select an appropriate antithrombotic agent and decide on the doses and duration of therapy in these patients.Several international and American societies have published clinical guidelines that reviewed evaluation of coagulation abnormalities in patients with COVID-19.3-6 To balance the risk of bleeding and preventing or treating thromboembolic events,a simplified practical summarisation is needed.
