Applications of rotational thromboelastometry in heparin monitoring in critical COVID-19 disease: Observations in the Maastricht Intensive Care COVID cohort.

Background: Critically ill COVID-19 patients are at risk for venous thromboembolism (VTE). Therefore, they receive thromboprophylaxis and, when appropriate, therapeutic unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH). To monitor heparins in COVID-19 disease, whole-blood rotational thromboelastometry (ROTEM) may be a promising alternative to the aPTT and anti-Xa assays.
Objective: To evaluate the ROTEM INTEM/HEPTEM ratios in mechanically ventilated COVID-19 patients treated with UFH and therapeutic LMWH.
Material and Methods: A subcohort of mechanically ventilated COVID-19 patients of the prospective Maastricht Intensive Care Covid (MaastrICCht) cohort was studied. Anti-Xa, aPTT, and ROTEM measurements following treatment with UFH or therapeutic dose of LMWH (nadroparin) were evaluated using uni- and multivariable linear regression analysis and receiver operating characteristics.
Results: A total of 98 patients were included, of which 82 were treated with UFH and 16 with therapeutic LMWH. ROTEM-measured INTEM/HEPTEM CT ratio was higher in patients using UFH (1.4 [1.3-1.4]) compared to patients treated with LMWH (1.0 [1.0-1.1], p < 0.001). Both the aPTT and anti-Xa were associated with the CT ratio. However, the β-regression coefficient (95%CI) was significantly higher in patients on UFH (0.31 (0.001-0.62)) compared to therapeutic LMWH (0.09 (0.05-0.13)) for comparison with the anti-Xa assay. Furthermore, ROC analysis demonstrated an area under the curve for detecting UFH of 0.936(0.849-1.00), 0.851(0.702-1.000), and 0.645(0.465-0.826) for the CT ratio, aPTT, and anti-Xa, respectively.
Conclusion: The ROTEM INTEM/HEPTEM CT ratio appears a promising tool to guide anticoagulant therapy in ICU patients with COVID-19 disease, but associations with clinical endpoints are currently lacking.
Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Renke H. Olie has received research support and honoraria from 10.13039/100004326Bayer, 10.13039/100004319Pfizer/BMS, Leo Pharma, Portola, and 10.13039/100004339Sanofi. Hugo ten Cate received funding for research from 10.13039/100004326Bayer and 10.13039/100004319Pfizer, is a stakeholder in Coagulation Profile, is a consultant for Alveron, and has served on advisory boards for 10.13039/100004326Bayer, 10.13039/100004319Pfizer, Daiichi, Leo, and Gilead. Yvonne Henkens has received ROTEM cartridges free of charge for previous research unrelated to the current manuscript. All others report no conflicts of interest.
(© 2023 Published by Elsevier Ltd.)