Prevention and Treatment of Venous Thromboembolism Key Clinical Questions
02. What labs should be ordered on admission, and how should these be followed?
a. HOMERuN institutions
The majority of protocols (71%) recommended specific laboratory testing on admission. There was good consensus that a complete blood count, PT/aPTT, D-dimer, and fibrinogen should be checked on admission and monitored through admission. Depending on severity of illness, recommendations for frequency of monitoring ranged from daily in critically ill patients to as infrequently as every 72 hours in less acutely ill patients.
b. What is Known
Very little is known about the prognostic value of any specific laboratory. General consensus appears to be that a low D-dimer in patients with COVID-19 with otherwise low suspicion for VTE remains reliable for ruling out thrombosis.
c. What is Not Known
Much more is unknown than known currently regarding the utility of laboratory tests of coagulation and thrombosis. While there is evidence that patients with elevated D-dimer (>3-6x ULN) have worse clinical outcomes in COVID-19, it is not clear if this is secondary to undiagnosed thrombosis or simply a marker for more severe systemic infection and inflammation.2,4,13
Key Clinical Questions
- Akima S, McLintock C, Hunt BJ. RE: ISTH interim guidance to recognition and management of coagulopathy in COVID-19. J Thromb Haemost. 2020;18(8):2057-2058. doi:10.1111/jth.14853
- COVID-19 Resources. Accessed August 24, 2020. https://www.hematology.org:443/covid-19
- Tang N, Bai H, Chen X, Gong J, Li D, Sun Z. Anticoagulant treatment is associated with decreased mortality in severe coronavirus disease 2019 patients with coagulopathy. J Thromb Haemost. 2020;18(5):1094-1099. doi:10.1111/jth.14817