Quality Improvement Program Improves Time in Therapeutic Range for Hemodialysis Recipients Taking Warfarin

INTRODUCTION: Studies have shown that achieving a time in therapeutic range (TTR) for warfarin of greater than 60% is associated with a lower risk of bleeding. However, many patients on hemodialysis (HD) do not achieve this target. METHODS: We audited TTR achievement at the in-center HD unit of our hospital in 2017 and found that only 40% of patients had achieved a TTR >60%. We aimed to improve the percentage of HD patients achieving target TTR within 2 years. We reported each patient's individualized trend in quarterly TTR to their primary warfarin prescriber as an audit-feedback report. These reports were generated, disseminated, and subsequently improved following a series of plan-do-study-act cycles. We then used statistical process control to assess for changes in the percentage of HD patients achieving target TTR over time. RESULTS: In the primary analysis, 28 patients were included in the baseline period, and 46 were included in the intervention period. At baseline, the percentage of patients achieving a TTR >60% varied between 33% and 45% (mean ± SD, 40% ± 5%); post-intervention, this metric improved and varied between 52% and 71% (mean ± SD, 61% ± 8%). In time-series analysis, there was evidence of statistically significant variation between the 2 periods and evidence of sustained improvement. CONCLUSIONS: A quality improvement program consisting of an audit-feedback report that raises awareness of the quality gap in TTR achievement can result in substantial improvement in the safe and efficacious administration of warfarin to patients receiving maintenance hemodialysis.