Optimal Amount of Anticoagulation to Prevent Thrombosis in Critically Ill Patients with COVID-19? 2023

NEJM Journal Watch

Aaron J. Calderon, MD, FACP, SFHM, reviewing Labbé V et al. JAMA Intern Med 2023 Mar 22

Hospitalized patients with COVID-19 have substantial risk for thrombosis. In previous studies, researchers have examined the optimal level of anticoagulation to prevent thrombosis without incurring excess bleeding risk in hospitalized and critically ill patients. Guidelines largely recommend prophylactic dosing (e.g., 40-mg enoxaparin) for patients in intensive care and therapeutic dosing for those on the wards (Blood Adv 2021; 5:3951. opens in new tab and NIH COVID-19 Treatment Guidelines: Antithrombotic Therapy. opens in new tab).

In this open-label, randomized, multicenter trial of 334 patients in France, researchers evaluated all-cause mortality and time to clinical improvement in patients admitted for COVID-19–related pneumonia and hypoxemia. Almost all patients (90%) were in intensive care, and pulmonary embolism was ruled out for all patients. All patients received standard-dose prophylactic anticoagulation, high-dose prophylactic anticoagulation (2× the standard dose), or therapeutic anticoagulation.

All-cause mortality and time to clinical improvement were similar among the three groups. However, compared with standard-dose prophylactic anticoagulation, high-dose prophylactic anticoagulation lowered the incidence of a composite secondary outcome (i.e., thrombosis, bleeding, and all-cause death), primarily due to a fourfold lower thrombosis rate (20% vs. 5%) with no excess major bleeding. Therapeutic anticoagulation did not provide further benefit over high-dose prophylactic anticoagulation.