Continuing antithrombotic treatment in patients undergoing invasive procedures

In what patients should antithrombotic treatment be continued despite surgery or invasive procedures?

Wendy Lim, MD: Typically, when we think about whether one should continue or discontinue antithrombotic therapy around invasive procedures or surgery, one has to balance the clotting risk, or the risk of thromboembolic events, if we are to stop the anticoagulant versus the risk of bleeding associated with the procedure.

If we elect to continue anticoagulation, it is typically for procedures where the bleeding risk is low. Importantly, if the bleeding is to occur, it occurs in a site that is visible and compressible. Examples of that would be minor dental procedures: few teeth extracted—2 or less—root canals, periodontal or gum surgery; or surgery such as cataract surgery, where typically when one operates in that area, the lens is avascular, so there is no cutting of vessels and a low bleeding risk.

For procedures, it would be things such as thoracentesis, paracentesis, or endoscopy where there is no biopsy or no polypectomy to be done. Typically, a lot of those procedures are looking for biopsy, and that is why we will often encounter a request to stop anticoagulants in those situations. But if it is simply done with the intent not to do any biopsies, it does not have to be discontinued.

There are limited studies examining whether one should stop anticoagulants. I think we assume that for most surgeries they are going to be causing bleeding to occur. But interestingly, there are some randomized studies looking at implantable cardiac devices, specifically pacemaker insertion and implantable cardioverter-defibrillator (ICD) or defibrillators. In those studies they compared patients who discontinued anticoagulants and bridged that period of time with low-molecular-weight heparin in the case of warfarin therapy, or they used one of the direct oral anticoagulants. They compared stopping the anticoagulant to continuing the anticoagulant through the procedure and found that hematoma over the site was less in the case of warfarin. They had to stop the other study a bit earlier because of insufficient numbers but suggested that you can continue on with anticoagulants for those particular procedures.

Those are generally the ones I would say that you can perform with anticoagulants without needing to discontinue.