Thromboembolism is one of the major complications after primary elective total hip and knee replacement surgery (resulting in considerable preventable morbidity and mortality) 1 and in patients with nonvalvular atrial fibrillation (AF; leading to cerebral ischemic stroke and systemic embolism). 2 Limitations of the conventional regimes for prophylaxis of venous thromboembolism with low-molecular-weight heparin (LMWH) include bleeding hematoma, local allergy, heparin-induced thrombocytopenia

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... I and type II, transient increase of liver enzymes, and the requirement for parenteral administration. 3 Anticoagulation in patients with AF using vitamin K antagonists (VKA) reduces the incidence of ischemic stroke and systemic embolism and mortality, but severe bleeding complications, including intracranial hemorrhage, may occur. 4 Also, VKA usage requires frequent dose adjustments to maximize the time in the therapeutic range of international normalized ratio values between 2 and 3. 5,6 Many interactions with food and drugs and the slow onset and offset of action of VKAs necessitate simultaneous administration of unfractionated heparins or LMWHs during induction of anticoagulation as well as during discontinuation of anticoagulation. The new oral anticoagulants (NOACs) have Keywords ► new oral anticoagulants ► dabigatran ► rivaroxaban ► point-of-care method ► urine Abstract Rivaroxaban and dabigatran are new oral anticoagulants (NOACs) that inhibit directly factor Xa and thrombin, respectively. These NOACs effectively prevent thromboembolic complications using fixed doses without the need for dose adjustment according to laboratory results. About 60% of rivaroxaban is cleared from circulation by glomerular filtration, 30% of which is excreted as active drug. About 80% of dabigatran is excreted into urine as active compound. Accordingly, both NOACs can be determined in urine by means of chromatographic methods. Only a few laboratories are able to perform such methods, and results are not available within short time frames. New methods have to be developed to obtain results within minutes and possibly as point-of-care (POC) techniques. This testing may be useful for special patient populations such as those with acute deterioration of renal function due to any disease, before surgical interventions, during unexpected bleeding or thrombotic episodes while on therapy with NOACs, the oldest and youngest populations, pregnancy, suspicion of overdose and intoxication, and to determine adherence to therapy. Here we describe results of a POC qualitative assay using urine samples from patients on treatment with dabigatran and rivaroxaban.