Correcting Low R Time on TEG with Activated Coagulation
Understanding Low R Time on TEG
- A low R time on TEG with activated coagulation is often associated with anticoagulant therapy, particularly with direct oral anticoagulants (DOACs) or vitamin K antagonists (VKAs), and can be corrected with prothrombin complex concentrate (PCC) and intravenous vitamin K 1, 2
- Normal R time typically ranges from 5-10 minutes, with values below this range suggesting hypercoagulability, which may increase thrombotic risk 3
Diagnostic Approach
- Assess the patient's medication history, particularly for anticoagulants, to guide the diagnostic approach for low R time on TEG 1, 2
- For patients on DOACs, specific assays such as diluted thrombin time (dTT) or ecarin clotting time (ECT) for dabigatran, and anti-Xa activity for rivaroxaban/apixaban, may provide additional information 2, 4
Treatment Algorithm for Low R Time
- For patients on vitamin K antagonists (VKAs), administer prothrombin complex concentrate (PCC) along with intravenous vitamin K, with dosing guided by INR level and clinical urgency 1
- For patients on direct oral anticoagulants (DOACs), consider idarucizumab (Praxbind) for dabigatran, and andexanet alfa or PCC for factor Xa inhibitors (rivaroxaban, apixaban) 2, 4
Monitoring Response
- Repeat TEG 15-30 minutes after intervention to assess response, targeting normalization of R time (typically 5-10 minutes) 3
- Monitor for signs of bleeding or thrombosis after intervention for low R time on TEG 1