Lean Six Sigma Methods Reduce and Sustain Troponin Turnaround Time (TAT) for Emergency Department Patients

Abstract

Heart disease is the leading cause of death in Illinois, and accounts for nearly 25% of all deaths in the US. Rapid lab testing for troponin as a biochemical marker for myocardial infarction (MI) is Emergency medicine standard of care, with goal for turnaround time (TAT) to results within 60 minutes. Our system (70,000 annual emergency visits and 47.8 average daily troponin tests performed) could not reliably meet this benchmark, with 33% of results being posted in greater than 60 minutes during baseline (1.9 Sigma). Emergency department troponin point of care testing was suggested to reduce TAT, however, at increased cost and sacrificing accuracy and standardization. Lean Six Sigma methods were used to define, measure, analyze, improve, and control the process. Baseline time for centrifugation and analysis averaged 55.4 minutes (SD = 3.77). Some specimens were processed twice due to interfering substances leading to centrifugation times over twenty minutes for a ten minute cycle. Improvements included: new collection tubes to reduce spurious results; a $3000 high speed tabletop 3-minute cycle centrifuge replaced the traditional tenminute spin device; and auto-verification and posting technology was validated and activated. Results showed decrease in daily average TAT to 33.2 minutes (SD = 2.25), a 40% improvement. New process met TAT benchmark 96% of the time (3.25 Sigma). The control plan has maintained stability of improvements since May 2012. Lean six sigma methods produced a significant and sustained system change marked by faster Troponin TAT, enhanced patient outcomes, reduced length of stay, increased patient, staff, and physician satisfaction, and annual cost avoidance of $291,000 for unnecessary point of care testing.