Deep Vein Thrombosis in Non-ICU COVID-19 Patients: An Additional Risk

Abstract

Introduction: Venous thromboembolism (VTE) encompasses two conditions, deep vein thrombosis (DVT) and pulmonary embolism (PE). Patients admitted to the intensive care unit (ICU) are at highest thrombotic risk. The incidence of VTE in COVID-19 patients is not definitely established, with studies reporting an incidence rate of 25 - 27%. Discussion: As the COVID-19 pandemic progresses, studies are reporting increased incidence of VTE in COVID-19 patients admitted in ICU. But there are not many studies reporting the incidence of DVT in non-ICU COVID-19 patients. Elevated levels of D-dimer indicate hypercoagulability, but it can also indicate inflammation. 68% of hospitalized COVID-19 patients had elevated D-dimer levels. Thus, D-dimer level at the time of admission does not co-relate with the development of VTE or its related complications in COVID-19 patients. One study reported that out of the total number of non-ICU COVID-19 patients who had signs or symptoms suggestive of DVT, 50% were detected to be positive on compression ultrasound scan. While some studies and international guidelines recommend the administration of LMWH in all hospitalized COVID-19 patients, some studies recommend that the physicians should closely monitor patients for development of signs and symptoms of DVT, and perform prompt diagnostic tests to aid early diagnosis and initiate anticoagulation. Hence, the treatment protocols vary widely across institutions, and the decision of thromboprophylaxis is also made on a case-by-case basis. Conclusion: Further studies are needed to establish the incidence of DVT in non-ICU patients, the predictive value of d-dimer levels to detect DVT risk, and an optimal therapeutic regimen of prophylactic anti-coagulant therapy in these patients.