Should the dose or duration of anticoagulants for the prevention of venous thrombosis be increased in patients with COVID-19 while we are awaiting the results of clinical trials?

Venous thrombosis is a frequent complication of coronavirus disease 2019, particularly in patients with severe disease on intensive care units. A high rate of thrombosis is seen despite the use of standard doses of prophylactic low-molecular weight heparin. This has led to the suggestion that increased doses of prophylactic anticoagulation should be tried. There are now several clinical studies in progress of increased intensity anticoagulation and other therapeutic interventions aimed at trying to reduce the rate of thrombosis. While the results of these studies are awaited some units have already introduced increased doses of anticoagulants for primary prevention of venous thrombosis into clinical practice. This article debates whether that is appropriate or whether we should only be using increased doses of anticoagulants within the context of clinical trials.