Screening for venous thromboembolism in patients with COVID-19

Abstract

Pulmonary thromboembolism and deep venous thrombosis occur frequently in hospitalised patients with COVID-19, the prevalence increases on the intensive care unit (ICU) and is very high in patients on extracorporeal membrane oxygenation (ECMO). We undertook a literature review to assess the usefulness of screening for peripheral venous thrombosis or pulmonary thrombosis in patients admitted with COVID-19. Outside of the ICU setting, D-dimer elevation on presentation or marked increase from baseline should alert the need for doppler ultrasound scan of the lower limbs. In the ICU setting, consideration should be given to routine screening with doppler ultrasound, given the high prevalence of thrombosis in this cohort despite standard anticoagulant thromboprophylaxis. However, absence of lower limb thrombosis on ultrasound does not exclude pulmonary venous thrombosis. Screening with CT pulmonary angiography (CTPA) is not justified in patients on the general wards, unless there are clinical features and/or marked elevations in markers of COVID-19-associated coagulopathy. However, the risk of pulmonary embolism or pulmonary thrombosis in ICU patients is very high, especially in patients on ECMO, where studies that employed routine screening for thrombosis with CT scanning have uncovered up to 100% incidence of pulmonary thrombosis despite standard anticoagulant thromboprophylaxis. Therefore, in patients at low bleeding risk and high clinical suspicion of venous thromboembolism, therapeutic anticoagulation should be considered even before screening, Our review highlights the need for increased vigilance for VTE, with a low threshold for doppler ultrasound and CTPA in high risk in-patient cohorts, where clinical features and D-dimer levels may not accurately reflect the occurrence of pulmonary thromboembolism.

The risk of venous thromboembolism and blood hyperlactatemia is associated with increased mortality among critically ill patients with Covid‐19

“…28 Microvascular thromboses are difficult to evaluate and often impossible to differentiate from other causes of organ dysfunction without autopsies. 29 Consistent with the literature, 20 this research also found that blood hyperlactatemia has been significantly associated with high mortality risk among critically ill Covid-19 patients in Saudi Arabia. A recent systematic literature review explored the possible association between increased blood lactate levels and mortality in Covid-19 patients and compared lactate values between Covid-19 and non-Covid-19 patients.…”

Predictive value of inflammatory and coagulation biomarkers for venous thromboembolism in COVID-19 patients

“…On one side, clinical features and symptoms of Covid-19 pneumonia and VTE greatly overlap, preventing us from assessing effectively the pre-test probability of VTE in Covid-19 patients [22,23]. On the other, D-dimer, which has a great negative predictive value for VTE in general population [24], is usually elevated in Covid-19 patients even in absence of VTE [8,[25][26][27].…”

Routine screening for pulmonary embolism in COVID-19 patients at the emergency department: impact of D-dimer testing followed by CTPA

“…Patients with COVID-19 are at increased risk of developing pulmonary embolism (PE) [ 1 – 4 ]. However, symptoms of COVID-19 and PE overlap, resulting in diagnostic challenges in patients presenting to the emergency department (ED) [ 5 , 6 ]. CT pulmonary angiography (CTPA) is considered the gold standard for PE, but performing this test in all COVID-19 patients would be logistically challenging, and lead to considerable costs and unnecessary exposure to radiation and contrast agents.…”