Abstract Number: PB0062
Meeting: ISTH 2022 Congress
Theme: COVID and Coagulation » COVID and Coagulation, Clinical
Background: Critically-ill COVID-19 patients on UFH present with heparin resistance (defined as >35.000 IU/day) to reach target aPTT or aXa. APTT is the conventional method as aXa is time consuming and not widely available. APTT or aXa relate differently to doses of UFH, which questions their validity in COVID-19 disease. Whole-blood rotational thromboelastometry (ROTEM) INTEM/HEPTEM clotting time (CT) ratio could be a more functional alternative.
Aims: Observational study comparing ROTEM INTEM/HEPTEM CT ratio, aPTT and anti-Xa in mechanically ventilated COVID-19 patients on UFH/LMWH.
Methods: We studied a subcohort (n=106/232) of mechanically ventilated COVID-19 patients of the MaastrICCht cohort. We measured ROTEM, aPTT and aXa on UFH (n=18) or therapeutic LMWH ( n=88). Patients received UFH (ECMO/renal replacement therapy) or therapeutic LMWH (venous thromboembolism/cardiac arrhythmia). ROC and Linear regression analyses were assessed for diagnostic characteristics and associations.
Results: INTEM/HEPTEM CT ratio was significantly higher in UFH-patients (1.4 [1.3-1.4]) compared to LMWH-patients (1.0 [1.0-1.1], p < 0.001) (Table 1). Furthermore, ROC analysis showed an AUC of 0.935 for INTEM/HEPTEM CT ratio, 0.775 for aPTT and 0.632 for aXa, suggesting that INTEM/HEPTEM CT ratio detects presence of UFH more accurately than aPTT and aXa. At an INTEM/HEPTEM CT cut-off of 1.1, sensitivity was 87.5% and specificity was 86.3% for the detection of UFH. Both APTT and aXa were positively associated with INTEM/HEPTEM CT ratio (β(95%CI) 0.006(0.004-0.008) and 0.153 (0.071-0.234) respectively, Table 2).Only, the association between aXa and INTEM/HEPTEM CT ratio was significantly stronger (p=0.006) in UFH-patients (β(95%CI) 0.310 (0.001-0.619), compared to LMWH-patients (β(95%CI) 0.094 (0.053-0.135).
Conclusion(s): ROTEM INTEM/HEPTEM CT ratio can detect the presence of UFH opposed to the presence of therapeutic LMWH in mechanically ventilated COVID-19 patients. INTEM/HEPTEM CT ratio was dependent on aPTT, irrespective of UFH or LMWH use. The association between aXa and INTEM/HEPTEM CT ratio was significantly stronger in patients on UFH than LMWH.
To cite this abstract in AMA style:
Schulting L, Hulshof A, Mulder M, Sels J, ten Cate H, van der Horst I, van Bussel B, Henskens Y. Rotational thromboelastometry in heparin monitoring in critical COVID-19 disease. [abstract]. https://abstracts.isth.org/abstract/rotational-thromboelastometry-in-heparin-monitoring-in-critical-covid-19-disease/. Accessed March 21, 2024.« Back to ISTH 2022 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/rotational-thromboelastometry-in-heparin-monitoring-in-critical-covid-19-disease/