Aims: Maintaining international normalized ratios (INRs) within the therapeutic range for patients on oral anticoagulant therapy is a tough task. Physician practices have a vital bearing on safe management in these patients. We sought to assess the knowledge base of clinicians in our hospital regarding oral anticoagulant treatment.
Methods: A retrospective review of 3152 consecutive INRs in patients on outpatient oral anticoagulant treatment (OAT) was carried out over a 16 month period. To assess clinician practices, we performed a questionnaire survey (20 questions) on various aspects of OAT among 65 clinicians (response rate--89%).
Results: 76.3% of the INRs were in the sub-therapeutic range, 19.1% in the therapeutic range while 4.6% INRs were beyond therapeutic range. Fifty five completed questionnaires were returned by 24 consultants and 35 residents. Knowledge of clinicians regarding the loading dose of the oral anticoagulant, target INR range, the colour of the tablet was not adequate with 21, 28 and 23 correct responses respectively. Documentation of dietary and drug history was inadequate with 13 and 38 responses respectively. Patient education was limited to only verbal information to patients on anticoagulation. Most clinicians performed baseline screens before starting therapy. Although majority of clinicians (41) reported haemorrhagic complications in patients, just under one-third (28.8%) clinicians encountered thrombosis more often. Significant differences between the knowledge of consultants and residents was only found in responses for the correct loading dose (p < 0.0007) and the laboratory methodology in use for PT/INR determination (p < 0.04).
Conclusions: Knowledge base of clinicians regarding oral anticoagulant management was unsatisfactory. A tendency to under-dose patients was observed. There is need for stricter adherence to accepted guidelines of anticoagulant therapy with particular emphasis on patient education.