Postprocedural management of warfarin therapy

For a guide to deciding whether and when to interrupt warfarin therapy, whether to use bridging therapy, and when to restart warfarin therapy if it is interrupted, see Stepwise approach to periprocedural use of warfarin. Ensure that postprocedural venous thromboembolism prophylaxis has been considered in the bridging therapy management plan; see Venous thromboembolism: prophylaxis for information.

If haemostasis has been achieved, consider restarting warfarin at the patient’s preprocedural dose within 24 hours of the procedure (this is usually the night of, or the night after, the procedure)Doherty, 2017Douketis, 2022.

For patients with atrial fibrillation taking warfarin for stroke prevention, or those with a mechanical heart valve, do not use postprocedural bridging therapy if the patient has a low or intermediate thromboembolic event riskKovacs, 2021. Even if these patients are at high thromboembolic event risk, the harm–benefit balance for postprocedural bridging therapy is not clear—only consider postprocedural bridging therapy if there is a low bleeding risk or a prolonged period when warfarin is withheld (eg no oral intake)Douketis, 2022Halvorsen, 2022.

For patients taking warfarin for prevention or treatment of venous thromboembolism (VTE) (particularly patients with high-risk antiphospholipid syndrome), postprocedural bridging therapy is recommended until warfarin achieves a therapeutic effect. This is important because after starting warfarin it takes several days for circulating coagulation factors to decrease, and the rapid fall in protein C and S levels initially increases prothrombotic potential. Consider consulting a haematologist regarding postprocedural bridging therapy in these patientsDouketis, 2022.

If postprocedural bridging therapy is considered appropriate and haemostasis has been achieved, add a parenteral anticoagulant to warfarin therapy 24 hours after a procedure with a low- to moderate-bleeding risk, or 48 to 72 hours following a procedure with a high bleeding riskDouketis, 2022Halvorsen, 2022. Stop the parenteral anticoagulant when the INR is 2 or more.

Before giving postprocedural bridging therapy, seek expert advice. Examples of dosage regimens are:

If using unfractionated heparin for postprocedural bridging therapy, it may be appropriate to use the same dose that was therapeutic before the procedure (if unfractionated heparin was given). Consult a local protocol for activated partial thromboplastin time (APTT) target values or seek specialist haematologist advice.