Abstract Number: PB0184
Meeting: ISTH 2021 Congress
Theme: COVID and Coagulation » COVID and Coagulation, Clinical
Background: The optimal prophylaxis for prevention of venous thromboembolism (VTE) in critically ill COVID-19 patients with acute kidney injury (AKI) is uncertain. Low-molecular-weight heparins are mainly excreted by the kidney and AKI may predispose to bioaccumulation with increased risk of bleeding. Dose adjustment or switch to unfractionated heparin is generally recommended, based on low quality evidence.
Aims: To describe trough anti-Xa activity in critically ill patients with and without AKI receiving prophylaxis with intermediate dose nadroparin.
Methods: This was a prospective cohort study including critically ill COVID-19 patients receiving intermediate dose nadroparin (5700IU once daily). Trough anti-Xa levels were measured twice weekly 20-25 hours after the previous dose. AKI was defined according to guideline criteria using serum creatinine and renal replacement therapy. The main outcome was the proportion of patients with bioaccumulation, defined as a trough anti-Xa level >0.2IU/mL at any time, in which case the dose had to be reduced. In patients with AKI and repeated measurements we calculated the range of trough anti-Xa values as a proxy for within-patient variation.
Results:
There were 234 trough anti-Xa measurements in 108 patients. In twenty-four patients 36 measurements were made during AKI. Two patients had evidence of bioaccumulation on a single measurement, 1 with and 1 without AKI (Figure 1). In 20 patients who had AKI and repeated measurements, the median range of anti-Xa values was 0.05IU/mL (IQR <0.04IU/mL – 0.08IU/mL; lowest range <0.04IU/mL; highest range 0.20IU/mL, Figure 2). Four patients had major bleeding events during hospital stay (2.4%; 95%CI 0.04%-8.9%) but none while on intermediate dose nadroparin.
Trough anti-Xa level according to acute kidney injury stage
Repeated trough anti-Xa levels in twenty patients with acute kidney injury
Conclusions: Bioaccumulation was rare in critically ill patients with AKI who received intermediate dose nadroparin for thrombosis prophylaxis. These data suggest there is no need for dose adjustment nor monitoring of nadroparin prophylaxis in patients with COVID-19 and AKI. The selected population may limit generalization to other patients.
To cite this abstract in AMA style:
Eck R, van Leur J, Lukens M, Bult W, Gans R, Meijer K, Keus F. Anti-factor Xa Activity after Intermediate Dose Nadroparin for Thrombosis Prophylaxis in Critically Ill COVID-19 Patients with and without Acute Kidney Injury [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/anti-factor-xa-activity-after-intermediate-dose-nadroparin-for-thrombosis-prophylaxis-in-critically-ill-covid-19-patients-with-and-without-acute-kidney-injury/. Accessed December 8, 2021.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/anti-factor-xa-activity-after-intermediate-dose-nadroparin-for-thrombosis-prophylaxis-in-critically-ill-covid-19-patients-with-and-without-acute-kidney-injury/