Prevention and Treatment of Venous Thromboembolism Key Clinical Questions
03. Should patients with CAC be treated, and if so, how?
a. HOMERuN institutions
The guidelines of institutions within the HOMERuN collaborative on the approach to treatment of CAC varied widely. First, most protocols did not directly address using blood products to correct laboratory findings of a coagulopathy with the only mention coming from three protocols (14%) which specifically recommending against empiric blood product transfusion without clinical evidence of bleeding. More commonly, guidelines addressed approaches to VTE prophylaxis as it pertained to CAC. All guidelines (21 total) reviewed recommended at minimum that standard dose prophylaxis for VTE be given to all patients with COVID-19 without a contraindication to anticoagulation. Beyond this base level of agreement, approaches to anticoagulation varied widely and included: four protocols (19%) which directly recommended against empiric anticoagulation based on laboratory evidence of coagulopathy (elevated D-dimer or fibrinogen) in contrast to three protocols (14%) which recommended consideration of empiric therapeutic anticoagulation based on elevated D-dimer or fibrinogen alone. Nine protocols (43%) recommended escalation from standard prophylaxis to higher or intermediate dosed anticoagulation based on laboratory findings (most commonly elevated D-dimer) in combination with high-risk clinical factors.
b. What is Known
Very little is known about appropriate treatment for CAC. As above, the most widely accepted expert opinion appears to be that all patients with COVID-19 without a contraindication to anticoagulation should receive standard dose VTE prophylaxis, although there is currently no evidence to directly inform this stance.
c. What is Not Known
There is currently no evidence that any specific approach to treatment is effective in reducing the thrombotic complications seen in patients with COVID-19, and further it is unclear if escalating degrees of VTE prophylaxis or more aggressive measures such as therapeutic anticoagulation or even thrombolysis are beneficial in patients with evidence of CAC or if they lead to iatrogenic harm.