Using Lean Six Sigma methodologies to reduce risk of warfarin medication omission at hospital discharge

Unintended omission of warfarin, an anticoagulant used to prevent and treat thromboembolic events, can lead to serious medical complications. These complications include increased medical costs, hospitalisations and significant patient harm, including increased risk of thrombosis and mortality. Chart review of discharged patients at our institution revealed an average of one patient/month with warfarin omitted from the discharge plan despite intention to continue therapy. Lean Six Sigma methodology was used to improve the process. A system alert was implemented in the electronic health record to alert providers of patients who received warfarin during admission, the discharge medication reconciliation was complete, and there was no prescription for warfarin. Date and time of last warfarin dose and international normalised ratio were included in the alert. Providers had the option to return to the chart to update the discharge medication plan and add the warfarin prescription or to choose an appropriate over-ride reason. The number of patients discharged without an intended warfarin prescription following alert implementation was reduced from 10.5% (4/38) to 0% (0/40) (two proportion test, p=0.03). Alert tracking enhanced the ability to identify patients at risk for warfarin omissions. Process sustainability has been achieved by embedding system alerts in the electronic health record to trigger process steps.