title: Root cause analysis of delays to discharge for patients held for serial cardiac troponin levels.
abstract: OBJECTIVE
  Emergency department (ED) patients with symptoms of cardiac ischemia often require a second cardiac troponin (cTn) measurement to rule out non-ST elevation myocardial infarction. We measured the total turnaround time and the component event times following the ordering of the second cTn level to ED discharge to identify root causes of delays.
  
  
  METHODS
  We reviewed a random sample of ED discharges following a second normal cTn measurement and recorded associated event times. The central tendency of time intervals is reported as median and mean number of minutes with interquartile ranges (IQRs) and 95% confidence intervals, respectively.
  
  
  RESULTS
  From 9,656 eligible cases, we randomly selected 226 for data collection. The median number of minutes for each event are as follows: from ordering the second cTn measurement to the time of ED discharge was 90 minutes (IQR 65-120); for blood collection from the time the collection was ordered for was 0 minutes (IQR -12-0); from blood collection to the time the blood was transported to the laboratory was 9 minutes (IQR 2-19); laboratory process duration was 44 minutes (IQR 39-52); from when the results were available to the time the patient was discharged was 30 minutes (IQR 15-52).
  
  
  CONCLUSIONS
  For ED patients discharged following two normal cTn levels, the laboratory processing time and time from the result being available to the time of ED discharge represent the longest modifiable time periods to reduce ED length of stay.
authors.forename: Julian
authors.initials: J
authors.lastname: James Owen
authors.forename: Andrew
authors.initials: A
authors.lastname: Worster
authors.forename: Barbara
authors.initials: B
authors.lastname: Marie Waines
authors.forename: James
authors.initials: J
authors.lastname: Ward
authors.forename: Peter
authors.initials: P
authors.lastname: Kavsak
authors.forename: Stephen
authors.initials: S
authors.lastname: Hill
mesh_terms: D001800:Blood Specimen Collection; D057210:Delayed Diagnosis / Q000706:statistics & numerical data; D004636:Emergency Service, Hospital / Q000458:organization & administration*; D006801:Humans; D009203:Myocardial Infarction / Q000175:diagnosis*; D010865:Pilot Projects; D060891:Root Cause Analysis; D014336:Troponin / Q000097:blood*
chemical_list: D014336:Troponin