Prevalence of Deep Vein Thrombosis among COVID-19 Patients using Colour Doppler Ultrasound in a Tertiary Care Centre of Central India: A Prospective Cohort Study

Introduction: Acute respiratory disease, Coronavirus Disease 2019 (COVID-19) is an infectious and potentially fatal respiratory disease. Increase in the inflammatory response, hypoxia, immobilisation are suggested mechanisms of procoagulant state. Deep Vein Thrombosis (DVT) and pulmonary emboli are common and often silent. Venous duplex ultrasound help in determination of the presence, extent, age of the thrombus and its attachment to venous wall.

Aim: To evaluate the prevalence of DVT by colour doppler ultrasound in lower limbs of mild to severe clinical categories of COVID-19 patients.

Materials and Methods: A time-bound, hospital-based prospective cohort study was conducted in the Department of Radiodiagnosis, MY Hospital, Indore, Madhya Pradesh, India, between March 2021 and February 2022. Study comprised 2200 cases of COVID-19 positive patients with elevated D-dimer levels i.e., >0.5 ng/mL and colour doppler imaging for lower limb. The clinical (co-morbidities, clinical severity) and radiological data (compressibility, colour flow) were studied and analysed using Statistical Package for the Social Sciences (SPSS) software version 25.0.

Results: In the present study, there were 1144 (53%) males and 1056 (47%) females. Out of 2200 patients, 792 (36%) patients showed presence of DVT. The most prevalent age group was 36-55 years having 506 (63.9%) patients. Majority of DVT positive patients were suffering with hypertension and diabetes i.e., 261 (33%) and 372 (47%) patients, respectively. Most commonly affected vein in DVT was Common Femoral Vein (CFV) in 704 (88.9%) patients. Superficial veins thrombosis was also associated with DVT affecting Short Saphenous Vein (SSV) in 439 (55.4%) patients and Great Saphenous Vein (GSV) in 221 (27.9%) patients.

Conclusion: There was a high prevalence of DVT among COVID-19 positive patients. Colour doppler ultrasound has provided an excellent aid in the diagnosis of DVT.