LAUSR

Objectives We evaluated rotational thromboelastometry (ROTEM) tracings in 44 critically ill coronavirus disease 2019 (COVID-19) patients, to determine whether there is a viscoelastic fingerprint and to test the hypothesis that the diagnosis and prediction of venous thromboembolism (VTE) would be enhanced by the addition of ROTEM testing. Measurements and Main Results ROTEM values reflected an increase in clot strength for the EXTEM, INTEM, and FIBTEM assays beyond the reference range. No hyperfibrinolysis was noted. Fibrinolysis shutdown was present but did not correlate with thrombosis. 32% (14/44) of patients experienced a thrombotic episode. For every 1 mm increase of FIBTEM maximum clot formation (MCF), the odds of developing thrombosis increased 20% (95% confidence interval (CI), 0-40%, p=0.043), whereas for every 1,000 ng/mL increase in D-dimer, the odds of thrombosis increased by 70% (95% CI, 20%-150%, p=0.004), after adjustment for age and sex (AUC 0.96, 95% CI, 0.90 - 1.00). There was a slight, but significant improvement in model performance after adding FIBTEM MCF and EXTEM clot formation time (CFT) to D-dimer in a multivariable model (p=0.04). Conclusions D-dimer concentrations were more predictive of thrombosis in our patient population than any other parameter. ROTEM confirmed the hypercoagulable state of COVID-19 intensive care unit patients. FIBTEM MCF and EXTEM CFT increased the predictability for thrombosis compared to only using D-dimer. ROTEM analysis is most useful in augmenting the information provided by the D-dimer concentration for VTE risk assessment when the D-dimer concentration is between 1,625-6,900 ng/dL, but the enhancement is modest. Fibrinolysis shutdown did not correlate with thrombosis.