ABSTRACT
Background: Continuous renal replacement therapy in the treatment of patients with active COVID-19 is frequently complicated by thrombosis in the extracorporeal circuit resulting in reduced filter lifespan, necessitating a revisited anticoagulation strategy. Methods: The standard regional citrate anticoagulation dose of 2.2 mmol/l was increased to a starting dose of 3.0 mmol/l and routine thrombosis prophylaxis with low-molecular-weight heparin was adjusted from a single dose of nadroparin 2850 IU to 5700 IU twice daily. In a non-randomised cohort study, the efficacy of high-dose anticoagulation was compared with a control group with standard anticoagulation. Results: Eleven COVID-19 patients requiring continuous renal replacement therapy were included, 42 filter sets in the control group and 37 filter sets in the high-dose anticoagulation group. The median filter lifespan was 48 hours in the high-dose anticoagulation compared with 18 hours in the control group (p<0.001). No significant effect on ionised calcium levels was observed in the high-dose group. Conclusion: The combination of high-dose regional citrate anticoagulation and increased-dose LMWH appears to prolong filter lifespan in patients with COVID-19.
ABSTRACT
INTRODUCTION: Coagulopathy in Coronavirus disease 2019 (covid-19) has been demonstrated by an increase in D-dimer, prothrombin time (PT), fibrinogen and factor VIII. Venous thromboembolic events are a common abnormality in patients with covid-19. We evaluate the results of intensive care unit (ICU) thrombosis prophylaxis of 5700 international unit (IU) nadroparin low molecular weight heparin (LMWH) twice daily. METHODS: After introduction of this high-dose pharmacological thrombosis prophylaxis twice weekly anti-factor Xa (anti Xa) concentrations and results from routine laboratory and viscoelastic hemostatic tests in 16 ICU covid-19 patients were evaluated. RESULTS: During one week, median peak anti Xa activities were 0.38 [0.16-0.45] and 0.38 [0.20-0.58] at time point 1 and 2 respectively. Laboratory coagulation tests showed PT, AT and platelet count (PltC) values within normal range and markedly increased D-dimer and fibrinogen levels. Viscoelastic tests showed a maximum clot strength just above normal reference value, while fibrin clot strength was strongly increased. The overall contribution of fibrin to clot strength was high with 71 [56-85]%. CONCLUSION: Anti Xa activity was within the target range of pharmacodynamic endpoint for covid-19 patients but viscoelastic tests still demonstrated a procoagulant pattern.