ABSTRACT
Venous thromboembolism (VTE), including deep vein thrombosis and pulmonary embolism, is an important complication in patients hospitalized in intensive care units (ICU). Thromboprophylaxis is mainly performed with Low Molecular Weight Heparin (LMWH) and, in some specific patients, with Unfractionated Heparin (UFH). These intensive units are an environment where individual patient variability is extreme and where traditional antithrombotic protocols are frequently ineffective. This was known for a long time, but the hospitalization of many patients with COVID-19 inflammatory storms suddenly highlighted this knowledge. It is therefore reasonable to propose variable antithrombotic prevention protocols based initially on a series of individual criteria (weight, BMI, and thrombotic risks). Secondly, they should be adjusted by the monitoring of anticoagulant activity, preferably by measuring the anti-Xa activity. However, we still face unresolved questions, such as once- or twice-daily LMWH injections, monitoring at the peak and/or trough, and poorly defined therapeutic targets. Equally surprisingly, we observed a lack of standardization of the anti-Xa activity kits.
ABSTRACT
It is now reported that coronavirus disease 2019 ICU patients are at increased risk of thrombosis. Expert opinion and scientific societies recommend a higher dose of low-molecular-weight heparin, but definitive data is lacking. We report our adapted thromboprophylaxis practice of low-molecular-weight heparin administration in coronavirus disease 2019 ICU patients. One-hundred six measurements in 19 ICU patients were collected. Despite enoxaparin 60 mg once daily, only two measurements of the trough anti-Xa were in the upper end of prophylactic range. Anti-Xa activity peaks increased significantly after administration, but all measurements were under the optimal prophylactic ranges. Despite an adapted protocol, three of the 19 patients (16%) developed venous thromboembolism. We show in coronavirus disease 2019 ICU patients, despite higher prophylactic low-molecular-weight heparin administration due to body mass index, anti-Xa activity was well below peak serum levels in our cohort of critically ill coronavirus disease 2019 patients. This evaluation suggests the need for rapid studies on adequate thromboprophylaxis in these patients.