Phlegmasia cerulea dolens associated with acute coronavirus disease 2019 pneumonia despite supratherapeutic warfarin anticoagulation.

Patients with acute coronavirus disease 2019 (COVID-19) respiratory infection are associated with concomitant thromboembolic complications and a hypercoagulable state. Although these mechanisms are not completely understood, unique alterations in the serum markers for hemostasis and thrombosis have been detected. A high index of suspicion is required by vascular surgeons for patients presenting with this novel virus. We present the case of a 51-year-old man with acute COVID-19 pneumonia who developed phlegmasia cerulea dolens despite chronic warfarin therapy and a supratherapeutic international normalized ratio.