Abstract WP169: Thromboelastography as a Biomarker of Emergent Direct-Acting Oral Anticoagulant Reversal With Prothrombin Complex Concentrates for Intracranial Hemorrhage

Abstract

Prothrombin complex concentrates (PCCs) are used to emergently reverse direct-acting oral anticoagulant (DOAC) activity. PCCs are recommended as an alternative to recombinant coagulation factor-Xa to reverse anticoagulation activity of apixaban or rivaroxaban. Measuring the degree of anticoagulation reversal in this population is limited. Thromboelastography (TEG) has been used to detect the presence of DOAC plasma levels in patients chronically taking a DOAC but has not been utilized to measure the effect on anticoagulant activity after PCC administration. We aimed to determine whether TEG R-time is useful in detecting the impact of PCC administration on anticoagulation activity in patients with anti-factor Xa-associated intracranial hemorrhage (ICH). We prospectively evaluated the utility of TEG to assess anticoagulation activity after factor Xa inhibitor reversal with 4-factor PCC. Adults with ICH taking apixaban or rivaroxaban were included. Patients were excluded if their last known dose of anticoagulation was >48 hours prior to arrival, had known apixaban or rivaroxaban blood levels <20 ng/mL, or had the following comorbidities: hepatic failure, hereditary disorders of hemostasis, polytrauma, or pregnancy. TEG samples were collected before PCC administration (if available), and 0.5, 12, and 24 hours after PCC administration. Thirty-one patients were enrolled between November 2022 and August 2023. The median PCC dose was 24.5 units/kg (IQR 20.3-26.9 units/kg; n=29). Nine patients received anticoagulation reversal after baseline TEG collection; the remainder received anticoagulation reversal at transferring facilities. Baseline R-time was negatively correlated with time since last dose of DOAC (n=9). A median decrease in R-time of 0.8 minutes after PCC (IQR -1.6 - 0.3; n=8) was found in patients with baseline TEG collection. R-time rebounded by a median of 0.75 minutes (IQR 0.2-2.0; n=8) from 0.5 hours to 12 hours after PCC administration (n=8). TEG R-time, a measure that inversely correlates with the degree of anticoagulant effect, rapidly decreases after PCC in patients taking DOACs that present with acute ICH. TEG R-time rebounds 12 hours after PCC administration. TEG-R time may be a useful biomarker in DOAC reversal with PCC.