Is Anti-Factor Xa Associated With Outcome in Patients With Critical COVID-19 on Low-Molecular-Weight Heparin?

Karolinska Institutet1,520 enrolled

Overview

Patients with critical COVID-19 are hyper-coagulable and optimal thromboprophylaxis treatment differs with stage and severity. The most commonly used drug for thromboprophylaxis in the intensive care unit (ICU) is low-molecular-weight heparin (LMWH). In contrast to unfractionated heparins, the effects of LMWH usually do not require monitoring. Exceptions from this are when elimination of LMWH is impaired, extremes in age and weight, to identify deviations from predicted pharmacokinetics, and if there is an unexpected clinical response. The unexpected high incidence of thromboembolic complications among patients with critical COVID-19 compared to critically ill non-COVID-19 patients could motivate monitoring. The activity of LMWH is monitored by quantifying the presence of anti-Factor Xa (aFXa). The aim of this study is to investigate if the level and the monitoring frequency of aFXa is associated to mortality, thrombosis and bleeding in patients with critical COVID-19 treated with LMWH and therefore could be used as a potential tool to guide LMWH-treatment.

Study Type

OBSERVATIONAL

Enrollment

1,520

Conditions

Covid19 Thromboembolism Bleeding

Interventions

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients with critical COVID-19 and respiratory failure * Positive SARS-CoV-2 test * LMWH-effect monitored by aFXa, as a trough or peak value, after at least four doses at a twice daily regime Exclusion Criteria: * Diagnosed thromboembolism or major bleeding during their COVID-illness prior to ICU-admission or as a reason or contributing factor for the ICU-admission. * Transferred to or from an ICU in other hospital/region making data collection regarding baseline data/outcomes not possible

Outcomes

Primary Outcomes

Mortality

90-day mortality

Time frame: 90 days from ICU admission

Secondary Outcomes

Thromboembolic events

Thromboembolic events are defined as the cumulative proportion of pulmonary embolism (PE), ischemic stroke and deep venous thrombosis (DVT). PE must be verified by computed tomography or by clinical suspicion as cause of deterioration combined with findings of acute strain of the right heart on echocardiography. Ischemic stroke must be verified by computed tomography. DVT must by verified by ultrasound or by computed tomography.

Time frame: 28 days from ICU-admission

Bleeding events

Bleeding events are categorized according to the World health organization (WHO) bleeding scale: 1) Petechiae, tissue hematoma, oropharyngeal bleeding, 2) Mild blood loss, hematemesis, macroscopic hematuria, hemoptysis, joint bleeding, 3) Gross blood loss requiring red blood cell transfusion and/or hemodynamic instability, 4) Debilitating blood loss, severe hemodynamic instability, fatal bleeding, or central nervous system bleeding.