Russels viper venom (RVV) clotpro essay correlates with anti-xa activity during veno-venous ecmo

Introduction: The ClotPro system (enicor GmbH, Germany) is a novel rotational viscoelastic analyzer that assesses the coagulation cascade through different reagents. Russels Viper Venom (RVV) is a direct activator of fX to fXa, and it is mostly employed to monitor direct oral anticoagulants. IN test evaluates the intrinsic pathway of coagulation via ellagic acid addition. The ability of these tests to monitor heparin administration during veno-venous ECMO (vvECMO)-compared to the gold standard anti-Xa activity-is to be cleared. Objective: To evaluate the correlation of RVV and IN test clotting time (CT) with anti-Xa activity during unfractioned heparin (UFH) administration in vvECMO. Methods: Intensive care unit (ICU) patients undergoing vvECMO and continuous UFH administration were enrolled. Standard coagulation tests, anti-Xa activity, RVV and IN test were simultaneously conducted. Results: Eight patients were enrolled (September 2020-February 2021), for a total of 53 observations (5 [2-9] per patient). SARS-CoV2 infection was the main diagnosis (50%), followed by Legionella pneumonia, HSV pneumonia, bridge to lung transplantation and COPD relapse. Age was 54.0 [42.5-60.5] years old, body mass index was 26.6 [24.1-28.5] kg/m2. Prolongation of RVV and IN CT was observed in our cohort (see Table 1 for the main study findings), and it was found to be strongly correlated to plasma anti-Xa activity (Figures 1, 2). Conclusions: RVV and IN test clotting time at ClotPro system might be used for anti-coagulation monitoring during vvECMO and UFH administration. Further studies are needed for clinical translatability of these findings.