Direct oral anticoagulants; a review for the non-specialist

Thrombin inhibitors and direct factor Xa inhibitors represent a major breakthrough in the field of anticoagulation pharmacotherapy. These novel agents have replaced warfarin as the oral anticoagulant of choice in certain indications, as they possess equal or superior efficacy and better safety profiles. They have a quick onset of action, predictable pharmacokinetic properties and minimal drug and food interactions. So they do not require frequent blood monitoring and dose adjustments as with warfarin. Considering all the advantages, there seems to be a rapid increase in the number of patients who are started on these novel anticoagulants. In this review, we highlight the pharmacology of these direct oral anticoagulants and the evidence-based indications for their use. We aim to provide a clinical overview for the non-specialist who may be called upon to manage a patient who is currently on one of these novel anticoagulants.

Postoperative Bleeding Complications in Patients on Novel Oral Anticoagulants and Vitamin K Antagonist Following an Invasive Dental Procedure - A Review of Literature

The incidence of thromboembolic diseases is high. It is one of the leading causes of death and disability. Anticoagulants are used for preventing or reducing blood clot formation and treatment of other related thrombotic disorders. Vitamin K antagonists (VKA) were developed more than 60 years ago. Warfarin is the most commonly used VKA. The drawbacks of vitamin K antagonists were that it requires frequent monitoring and dose adjustments, food and drug interactions, narrow therapeutic range, diet restrictions. For the past 15 years, various new drugs have been introduced to overcome the disadvantages of vitamin K antagonists. In 2008, a new group of anticoagulants were introduced. They are known as novel anticoagulants (NOAC) or direct oral anticoagulants. They include dabigatran, apixaban, rivaroxaban and edoxaban. The major issue with NOAC is difficulty in monitoring the dose. A literature search was done on this topic. It is very important for the dentists to know the bleeding complications in patients under anticoagulant therapy. The dental treatment of patients who tend to have an increased risk of bleeding due to the use of anticoagulants and / or antiplatelet drugs raises a challenge in the daily practice of dental professionals. According to current evidence, there is no significant difference in postoperative bleeding between novel anticoagulants and vitamin K antagonists. The risk of thromboembolic events on stopping the anticoagulants should be assessed. Local haemostatic measures are shown to suffice to control possible bleeding secondary to dental treatments. KEY WORDS Anticoagulants; Apixaban; Dabigatran; Dentistry; Edoxaban; Rivaroxaban.

Thromboelastogram-Guided Resuscitation for Patients with Traumatic Brain Injury on Novel Anticoagulants

Traumatic brain injuries in patients on antithrombotic agents carry significant morbidity. Initial therapy is centered around reversal of these agents. The thromboelastogram (TEG) maps the clotting cascade to guide reversal. A retrospective chart review was conducted for 118 patients presenting with a traumatic brain injury while on antithrombotics. Patients were divided between those who received a TEG on arrival and those who did not. The primary endpoint was overall mortality. Secondary endpoints included blood product utilization, and outcomes associated with specific novel anticoagulants. Mortality in the control group was 20.3 per cent compared with 18.5 per cent in the TEG group ( P = 0.81). For less severe injuries, the control group mortality was 3.8 per cent and the TEG group mortality was 8.7 per cent ( P = 0.64). For more severe injuries, mortality in the control versus TEG groups were 31.6 per cent and 25.8 per cent, respectively ( P = 0.73). Blood product utilization was significantly lower in the TEG group ( P = 0.002). Overall mortality was not significantly different between the groups. However, when stratified by severity of injury, mortality was reduced in the TEG-guided group in severely injured patients. Blood product utilization was significantly reduced with TEG-guided reversal. Trauma centers can improve the utilization of blood products in reversal of antithrombotics with the use of TEG.