Over the past month we have been looking at some different ways to measure and describe how a trauma system is performing.  In the world of performance improvement the general belief is that you have to look at a number of different measures in order to be able to describe how the system is performing.  Here goes: 

  • Over-Triage – In 2011, 35% of patients treated at a level I trauma center had minor injury and went home after being treated in the emergency department.  Most folks would consider this result to be on the high side (for the way we measure it). 
  • Under Triage –In 2011, 27% of patients with moderate to severe injuries were treated at a hospital that was not specially designated to handle their injuries.  This is considered to be a too high a percentage of patients not being taken to trauma centers.  Generally you aim for around 5% under triage. 
  • Z Statistic – Blunt: Between 2008 and 2011 there were a total of 50,036 blunt trauma patients treated at the seven level I trauma centers. The Z-statistic results suggest that there were more survivors than expected (0.54 additional survivors for every 100 patients) and fewer deaths than expected (14%).  These are really good results and show that our level I trauma centers are doing a good job caring for blunt injuries. 
  • Z Statistic – Penetrating: Between 2008 and 2011 there were a total of 7,957 penetrating injury patients treated at the seven level I trauma centers The Z-statistic results suggest that there were more survivors than expected (0.3 excess survivors over every 100 patients) and that the number of deaths was the same as expected. These are also pretty good results; we are better than average for penetrating injuries once a patient gets to the level I trauma center. 
  • ED Dwell Time: From 2008 to 2011, the average length of time patients stayed in the level IV emergency department before being transported to a level I trauma center was about 3 hours.  This result shows that we can be more efficient in transferring patients to the level I trauma center. 

What do these results tell us?  A few things:  1) we need to make sure that moderate and severely injured patients get to the right trauma center and that more minor injured patients stay at their local hospitals (our EMS medical directors and EMS Regions will play a key role in making that happen); 2) our level I trauma centers need to keep up the good work with blunt patients and see if they can raise the bar for penetrating injuries; and 3) our level I trauma centers need to reach out to the level IV trauma centers and help them reduce the time it takes to transfer trauma patients. 

We’ll continue our work with the State Trauma Advisory Board, the EMS Council, the Medical Direction Commission and the Trauma and EMS Performance Improvement Standing Committee to track and improve the Arizona trauma System.