Root cause analysis of laboratory delays to an emergency department

Abstract

The Q-Probes study has identified benchmark interinstitutional laboratory median turnaround times (TAT) of 25 min for hemoglobin and 36 min for potassium. Our objectives were to measure the emergency department (ED)/laboratory TAT and other relevant laboratory processing and reporting times, and to identify root causes of laboratory delay. A flow chart was developed for the ordering, collecting, analyzing, and reporting of laboratory results. Time intervals were prospectively recorded for complete blood count (CBC) and K + in a cross-sectional study, using the flow chart, and defined as follows: TAT was the interval from blood draw (BD) to ED report; BD time was the interval from order processing to BD; and order processing time was the interval from physician ordering to the unit coordinator processing the orders. Median times with interquartile ranges are reported. CBC TAT was 38 min (29–51.5), and K + TAT 58 min (45–76.5). Order processing time was 7 min (4–15). The laboratory assistant BD time was 17 min (8–30) for CBC and 15 min (7.75–31.25) for K + as compared to 0 min for a nurse, yet the venipuncture method (laboratory assistant technique) had a recollection rate of 1% ( 1 93 ) due to hemolysis vs. 20% ( 19 95 ) via the i.v. catheter (nurse technique). Of stat ED blood work, 24% was for admitted patients held in the ED. Laboratory reporting times are delayed with these root causes: laboratory assistant availability; recollection rate; volume of tests for ED admitted patients; and order processing time.