How to screen and diagnose deep venous thrombosis (DVT) in patients hospitalized for or suspected of COVID-19 infection, outside the intensive care units

Abstract

Introduction: The Coronavirus disease-2019 outbreak (COVID-19) has been declared a pandemic by the World Health Organization. Studies report both a severe inflammatory syndrome and a procoagulant state in severe COVID-19 cases, with an increase of venous thromboembolism, including pulmonary embolism (PE) and deep vein thrombosis (DVT). In this context, we discuss the use of doppler ultrasonography (DUS) in the screening and diagnosis of DVT in ambulatory and hospitalized patients with, or suspected of having, COVID-19, outside the intensive care unit (ICU).

Material and methods: Non-systematic review of the literature.

Results: In patients hospitalized for or suspected of COVID-19 infection with the presence of either (a) DVT clinical symptoms, (b) a strong DVT clinical probability (Wells score>2) or (c) elevated D-dimer levels without DVT clinical symptoms and without PE on lung CT angio-scan, DVT should be investigated with DUS. In the presence of PE diagnosed clinically and/or radiologically, additional systematic DVT screening using DUS is not recommended during the COVID-19 pandemic. The use of 4-points compression DUS for DVT screen and diagnosis is the most appropriate method in this context.

Discussion: Systematic DUS for DVT screening in asymptomatic COVID patients is not recommended unless the patient is in the ICU. This would increase the risk of unnecessarily exposing medical staff to SARS-CoV-2 and monopolizing limited resources during this period.

Keywords: COVID-19 associated coagulopathy; COVID-19 pandemic; Doppler ultrasound; Four-points compression ultrasound; Pulmonary embolism; Venous thromboembolism; Wells score.

Figure 1

CT angiogram performed in a 57-year-old patient who tested positive for SARS-CoV-2 in April 2020 and was hospitalized in the infectious disease unit for acute respiratory failure. Left panel: typical of COVID-19 images of the parenchymal window showing ground glass opacities in the lung bases. Right panel: mediastinal window showing the presence of a small endoluminal defect in the right lower lobe sub-segment indicative of a pulmonary embolism.

Figure 2

Linear probe compression test, mode B, cross section on the popliteal fossa. The popliteal vein can be compressed, thereby confirming that this is not a site of thrombosis. The artery is not compressible. PV: popliteal vein, PA: popliteal artery, SSV: small saphenous vein.