Bleeding & Dabigatran

Bleeding with Dabigatran 

I could not be more thrilled to see all the new oral anticoagulation options emerge.  Warfarin can be difficult to manage due to its many drug interactions and need for frequent monitoring.  One of the questions that seems to have arisen with some of the new oral anticoagulants if our patients are being placed in additional risk of a thromboembolic event or a bleed due to our inability to monitor levels and predict drug effect in certain patient populations.

Dabigatran is a direct thrombin inhibitor marketed in 2010 for prevention of stroke in atrial fibrillation.  While no difference in bleeding was seen with the 150mg twice daily dose compared to warfarin, the medication is not risk free.

The Food and Drug Administration (FDA) is currently reviewing case reports of bleeding with the manufacturer, Boehringer Ingelheim, to develop better monitoring and risk assessment strategies.

Unlike warfarin, there is currently no reversal method for the effects of dabigatran save for emergency dialysis.  The author of an editorial published in The New England Journal of Medicine expresses concern over the poor outcomes of patients taking dabigatran admitted for trauma.  While warfarin is far from perfect, we are able to reverse some of its effects with the administration of vitamin K.

Patients are at a greater risk of bleeding if they are 75 years old or greater, have kidney problems, or have a history of stomach bleeding.  In patients with renal dysfunction, the risk of bleeding is greater even with the reduced dose.  Renal function should be monitored frequently in these patients.

References:

Bleeding with dabigatran. Cotton BA, McCarthy JJ, Holcomb JB.  Acutely injured patients on dabigatran.  The New England Journal of Medicine 2011;365(21):2039-40.