Antithrombin levels and heparin responsiveness during veno-arterial extracorporeal membrane oxygenation: a prospective single-center cohort study
Background. Unfractionated heparin, administered during veno-arterial extracorporeal membrane oxygenation to prevent thromboembolic events, largely depend on plasma antithrombin for its antithrombotic effects. Decreased heparin responsiveness seems frequent on extracorporeal membrane oxygenation however its association with acquired antithrombin deficiency is poorly understood. Our objective was to describe longitudinal changes in plasma antithrombin levels during extracorporeal membrane oxygenation support and evaluate the association between antithrombin levels and heparin responsiveness. We hypothesized that extracorporeal membrane oxygenation support would be associated with acquired antithrombin deficiency and related decreased heparin responsiveness.Methods. Adults receiving veno-arterial extracorporeal membrane oxygenation were prospectively included. All patients received continuous intravenous unfractionated heparin using a standardized protocol (target anti-Xa 0.3-0.5 IU.mL –