An audit of patients' compliance with the standards for warfarin therapy

Abstract

INTRODUCTION AND OBJECTIVES: Warfarin is an oral anticoagulant with complex pharmacokinetics and pharmacodynamics. Therefore close monitoring is essential. Strict adherence to therapy depends on the patient's knowledge regarding anticoagulation. The objective was to assess patients' essential knowledge on warfarin with regard to anticoagulation therapy. METHODS: An audit was conducted over 6 months at Colombo North Teaching Hospital. 50 consecutive patients, of both genders, who had been on warfarin for at least 1 month were recruited. Their knowledge of warfarin therapy was evaluated using a 10 item questionnaire. Results were analyzed and compared against standards. RESULTS: Male:female ratio was 4:6 and mean age was 59.7 years. 46 % of patients had completed education up to Ordinary Level, 6% had never attended school. Indications for warfarin included: VTE 46 %, atrial fibrillation 28%, chronic cardiac dysfunction 22%, prosthetic heart valves 2%, and pulmonary hypertension 2%. 62% knew their current dose of warfarin, 4% were aware of their therapeutic INR, 68% knew what remedial action should be taken in the event of a haemorrhage, 48% were aware of effects of over anticoagulation, 22% were aware of effects of subtherapeutic anticoagulation, 86% were aware of interference of green leaves with therapy, 40% were aware ofNSAID affect anticoagulation, 70% were aware of alcohol effect on anticoagulation. CONCLUSION: As results did not meet standards, we suggest there should be better patient education regarding warfarin therapy. Patient information leaflets as well as information of this audit be made aware to teams concerned for better care of patients.