Pharmacy-managed anticoagulation: Assessment of in-hospital efficacy and evaluation of financial impact and community acceptance

Abstract

The dangers of thrombosis are well known and yet current therapy presents a paradox; effective methods of pharmacological anticoagulation are available, but underemployed. The risks associated with the use of anticoagulants, especially warfarin, and the requirement of meticulous dosing with subsequent vigilant monitoring provides some explanation for this discrepancy. Efforts have been made to address this incongruity and increase anticoagulation treatment while mitigating complications; these include the development of dosing nomograms, patient self-monitoring of anticoagulation status, and increased pharmacist participation in anticoagulation management. Although the latter option has proven effective in outpatient clinics, its in-hospital application has received less attention. Therefore, our primary goal was to review the published literature to evaluate the efficacy of in-hospital, pharmacy-managed anticoagulation. In addition, our secondary goals were to assess the potential financial benefit and community acceptance of such pharmacist management. Potentially relevant studies were identified by searching PubMed; however, because some pharmacy journals are not included in this database, we also used internet search engines to locate articles. We subsequently employed the Science Citation Index to find additional papers that had referenced articles identified by our initial searches. Several pilot studies, focusing primarily on adherence to warfarin dosing guidelines, found general equivalence between pharmacist and physician management and specifically illustrated the potential benefit gained simply through adherence to protocols. Nevertheless, these studies frequently lacked appropriate statistical analysis and examined small, and often heterogeneous, patient groups. Larger comparative studies also possessed some of the same flaws; however, taken together the equivalence and, in some cases improvement, in patient outcomes (e.g., greater control of International Normalized Ratios and decreased length of hospital stay) that they demonstrated suggest the value of increased pharmacist participation in anticoagulation therapy. Studies using heparin-based anticoagulation reported similar positive findings and hence support the warfarin results. Both published studies examining financial implications of in-hospital pharmacy management indicated potential for considerable savings. Finally, although we identified no in-hospital studies of community acceptance, positive survey results indicted that the majority of physicians and patients accepted pharmacy-managed outpatient anticoagulation. The reported outcomes of pharmacy-managed in-hospital anticoagulation therapy appear at least equal, and sometimes superior, to those obtained through standard care; however, the lack of large well-designed trials prevents drawing definitive conclusions. Nevertheless, the continued and likely increased future need for anticoagulation in general and warfarin therapy in particular suggests that increased pharmacist involvement could enhance the quality of patient care.