Pharmacy-Based Model Enabling Patient Self-Monitoring of Warfarin: Development and Evaluation

International research has established that patient self-monitoring (PSM) represents the gold standard for warfarin management. However PSM is not well established in Australia. This project aims to develop and implement a program to enable Australians taking warfarin to be provided with the necessary training and support to perform PSM. A total of 30 patients will be involved in this trial, which will be conducted in NSW and Tasmania. Selected community pharmacies will identify participants according to a set of criteria which includes a willingness of the consumer to participate, a previous history of warfarin usage of at least 6 months and consent of the consumer's general practitioner (GP). Participants will be supplied with comprehensive education on warfarin and their disease state by a trained accredited pharmacist who will provide an education session with the aid of a warfarin manual developed by the project team. This manual and additional warfarin educational material, also developed by the project team, will be given to consumers for later reference. A pre-validated warfarin questionnaire will be used to assess the consumer's warfarin knowledge. They will then be trained to use a point of care (POC) device, which measures the International Normalised Ratio (INR), by an accredited pharmacist and this will usually involve one 2 hour session within the consumer's home. The consumer must demonstrate proficiency with this device by providing two separate INR readings that are within 15% of a laboratory result taken on the same day. In each instance this will involve the consumer performing a test INR measurement, which takes about three minutes and involves placing a drop of capillary blood on a test strip in the POC device, followed on the same day by their GP taking a sample of their venous blood for pathology testing. Once they have been trained to perform PSM, consumers will use the POC unit to measure their INR. An INR measurement will be taken every 2 weeks and the result obtained will be supplied to their GP, for warfarin dosage adjustment, over a period of 6 months. In addition, if considered appropriate, GPs can direct their patients to provide more frequent INR results or to have pathology confirmation of results obtained using the POC device at any time during this study. Data on clinical outcomes such as minor and major bleeding will be collected as well as the percentage of time spent by participants in the target INR range. These results will be compared with outcomes obtained over a 6 month pre-trial period for participating consumers.