Abstract: objective To evaluate the rationality of warfarin application in hospitalized patients, as well as the safety and adherence when they leaved hospital, obtain foundation for further research. Methods A sophisticated research was conducted on all patients who were admitted to the department of cardiology from Jan. 1st, 2015 to Dec. 31st, 2015 and had record of warfarin usage. In the research, we analyzed their cases retrospectively and systematically, assessing the rationality of their warfarin application in hospital. We also investigated their specific warfarin usage and their intervals of repeated International Normalized Ratio (INR) testing by telephone follow-up method, assessing the safety and adherence of their warfarin application at discharge time. Results A total of 139 patients (65 males and 74 females, ages ranging from 36 to 74, average age (68.52±10.02)) were enrolled in this research. When hospitalized, 38.30% of the patients had large-range warfarin dose adjustment, 76 patients had reasonable INR testing results and 63 had unreasonable results. When leaving the hospital, only 32.59% of the patients met the INR intensity goals, 42.98% of the patients were advised by their doctors to determine blood coagulation function on specific dates at discharge time. Among the 122 patients (17 patients unable to contact) who were investigated by phone calls at discharge time, 9 patients stopped taking pills without doctors' instructions, 8 patients had adverse reactions, and 64.76 % of patients' latest INR met targets. Conclusion The main problems of warfarin application are as follows: determined INR infrequently when hospitalized, low ratio of meeting target INR intensity when leaving hospital, and weak adherence of regular INR monitoring. Medication education and long-term telephone follow-up on patients may improve the safety and adherence of warfarin application.

Key words: anticoagulant, warfarin, rationality, safety, adherence