Safety of Oral Anticoagulants Registry

Purpose and Rationale: Until recently, warfarin was the only oral anticoagulant (OAC) available in the US, and a substantial infrastructure has developed around its management. Over the past five years, four non-Vitamin-K antagonist oral anticoagulants (NOAC) have been approved by the FDA. The NOACs are associated with generally fewer and less severe bleeding complications, and shorter half-lives, often making management of bleeding that complicates the use of these agents less problematic than similar episodes associated with warfarin. Bleeding during NOAC therapy does occur, and patients taking NOACs sometimes require procedures that cannot be delayed, for which good hemostasis is desirable, and therefore the NOAC may delay or complicate care. The challenge of this latter issue is compounded by the lack of readily available, rapid-turnaround quantitative assays for measuring the magnitude of anticoagulation effect associated with NOAC use. From a safety perspective, the large warfarin infrastructure does not translate into useful support for use of the new NOACs; their anticoagulation impact cannot be readily monitored by simple, quick tests. In October 2015 the first specific reversal agent for a NOAC was approved, but it is useful only for dabigatran; at present, there is no specific reversal agent for anti-Xa NOACs. Emergency care providers face many concerns and insecurities regarding the safety of warfarin and the NOACs, while working in a highly pressurized care environment, often with limited patient history and little time to consider treatment options. Because of the unique position of the hospital ED in the US healthcare continuum, it is frequently the initial site of care for patients on OACs who develop bleeding complications. In all clinical settings, there tends to be a standardized, international normalized ratio (INR)-driven pathway for the management of warfarin-related bleeds. Many EDs and hospital pharmacies are now trying to establish similarly standardized, though not evidence-driven, pathways for NOAC-related bleeding, and eagerly await the availability of additional specific reversal agents to use in such patients. The ED represents the key sentinel surveillance point for assessing the clinical and economic impact of bleeding concerns and complications attributable to OAC therapy. Other bleeding issues that impact the pace and nature of medical and surgical care occur in the inpatient setting, especially the ICU and surgical suite. Taken together, the hospital setting (ED plus inpatient) offers a 360-degree view of the scope, significance, and cost of OAC-related bleeds and bleeding concerns. This registry is proposed as a large, prospective, multicenter study that identifies the clinical and economic impact of safety concerns around OAC use on evaluation and management strategies in the ED and on the inpatient units of participating hospitals. The eventual aim will be to use these data to inform the gradual development of a new, protocolized safety standard in the management of OACs in the ED.