Introduction: Novel oral anticoagulants (NOACs) have at least equivalent efficacy compared to standard anticoagulants with similar bleeding risk. Optimal management strategies for bleeding complications associated with NOACs are currently unestablished.Materials and Methods: A working group comprising haematologists and vascular medicine specialists representing the major institutions in Singapore was convened to produce this consensus recommendation. A Medline and EMBASE search was conducted for articles related to the 3 available NOACs (dabigatran, rivaroxaban, apixaban), bleeding and its management. Additional information was obtained from the product monographs and bibliographic search of articles identified. Results: The NOACs still has substantial interactions with a number of drugs for which concomitant administration should best be avoided. As they are renally excreted, albeit to different degrees, NOACs should not be prescribed to patients with creatinine clearance of <30 mLs/min. Meticulous consideration of risk versus benefits should be exercised before starting a patient on a NOAC. In patients presenting with bleeding, risk stratification of the severity of bleeding as well as identification of the source of bleeding should be performed. In life-threatening bleeds, recombinant activated factor VIIa and prothrombin complex may be considered although their effectiveness is currently unsupported by firm clinical evidence. The NOACs have varying effect on the prothrombin time and activated partial thromboplastin time which has to be interpreted with caution. Routine monitoring of drug level is not usually required. Conclusion: NOACs are an important advancement in antithrombotic management and careful patient selection and monitoring will permit optimisation of their potential and limit bleeding events.
Novel oral anticoagulants (NOACs) are designed to overcome the limitations of existing anticoagulants, and have been shown in clinical trials to be viable alternatives to heparins and vitamin K antagonists. Three NOACs are currently registered in Singapore. Rivaroxaban (Bayer Schering Pharma AG, Germany), an oral factor Xa inhibitor (anti-Xa), is approved for prophylaxis against venous thromboembolism (VTE) in orthopaedic
surgery, prevention of stroke and systemic embolism in patients with non-valvular atrial fi brillation (NVAF) and treatment of acute deep vein thrombosis (DVT) as well as prevention of recurrent DVT and pulmonary embolism (PE). Dabigatran (Boehringer Ingelheim, Germany), an oral direct thrombin inhibitor (DTI), is indicated for orthopaedic VTE prophylaxis and prevention of stroke and systemic embolism in NVAF. A second anti-Xa, apixaban (Bristol Myers Squibb, USA), has been approved for VTE prophylaxis in orthopaedic surgery and prevention of stroke and systemic embolism in NVAF.
This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.