Will Diversion of Less Urgent Patients Reduce Emergency Department Access Block?

1. Grant Innes^, Raul Martinez+, Michael Johnson+, Eric Grafstein*+^Alberta Health Services (Calgary), +Vancouver Coastal Health; *Providence Health Care and St. Paul's Hospital Will Diversion of Less Urgent Patients Reduce Emergency Department Access Block?

2. Disclosure • I do not have an affiliation (financial or otherwise) with any commercial organization that may have a direct or indirect connection to the content of my presentation.

3. Background • Emergency department (ED) overcrowding, better termed access block, is a situation where patients cannot access emergency care because all ED stretchers are occupied. • Many health experts believe that diversion of less urgent pts to other care locations (e.g. urgicentres) is an important part of the solution to access block. • Our objective was to estimate the impact of less urgent patient diversion on ED access block in an urban Canadian hospital, and compare that against other initiatives.

4. Methods • We captured arrival and departure times, triage acuity levels and disposition for all pts seen over a one-year period at an urban tertiary ED. • Based on a 2-week observation of actual pt placements, we found that all admitted pts and 60% of non-admitted pts required a stretcher: • all CTAS1-2, • 79% of CTAS 3-4 • 0% CTAS 5.

5. Methods • Using a simulation model queuing system, we conducted a scenario analysis to determine how many stretchers were required to assure a 90% access rate (stretcher available for patients who need one 90% of the time). • We then modeled the impact of diverting 10% or 50% of CTAS level 4-5 patients and of reducing ED boarding times for admitted patients to 10 or 6 hrs.

6. Results • During the study period, 62,100 patients were treated, including 30,040 CTAS 1-3 patients, and 32,060 CTAS 4-5 patients. • The model predicted that, at baseline, with an average admitted patient boarding time (LOS) of 15.5 hours, 50 ED stretchers would be required to achieve a 90% access rate.

7. Baseline State Access Rate vs. Stretcher Capacity ADM LOS=15.5 hr 50 str for 90% access

8. Access Rate vs. Stretcher Capacity 10% less urgent pts removed Access Rate vs. Stretcher Capacity ADM LOS=15.5 hr 50 str for 90% access

9. Access Rate vs. Stretcher Capacity 50% of less urgent patients removed Access Rate vs. Stretcher Capacity With no reduction in ADM pt LOS, access curve does not shift ADM LOS=15.5 hr 47 str for 90% access

10. Access Rate vs. Stretcher Capacity Baseline State Access Rate vs. Stretcher Capacity ADM LOS=15.5 hr 50 str for 90% access

11. Access Rate vs. Stretcher Capacity ADM Patient LOS reduced to 10 hr Access Rate vs. Stretcher Capacity ADM LOS=10 hours 38 str for 90% access

12. Access Rate vs. Stretcher Capacity ADM Patient LOS reduced to 6 hr Access Rate vs. Stretcher Capacity With red’n in ADM patient LOS, access curve does shift ADM LOS=6 hours 33 str for 90% access

13. Access Rate vs. Stretcher Capacity ADM Patient LOS reduced to 6 hr Access Rate vs. Stretcher Capacity ADM pt LOS= 6 hrs, AND 50% less urgent patients removed ADM LOS=6 hours 30 str for 90% access

14. Results: Number of Stretchers required to achieve 90% access target

15. Discussion • removing 10% of CTAS 4-5 visits had no impact on ED stretcher requirement, • removing 50% of less urgent patients reduced ED stretcher requirement by 6%. • reducing admitted pt boarding time to 10 hrs reduced stretcher requirement by 24%. • reducing admitted patient boarding time to 6 hours reduced stretcher requirement by 32%. • CTAS 4-5 patients less often need stretchers and occupy stretchers for less time, they have little impact on access for urgent and emergent patients

16. Limitations • Model outputs are highly dependent on input assumptions. These may vary in different settings • % of patients requiring stretcher varies by site • Local practice (e.g. SJH Model) • Specific problems (e.g. CTAS 4 pts for sed’n/I+D) • Cannot model the complexity of real ED operations and ED contingency responses • Didn’t consider how long pt needs stretcher, and whether pts removed from stretchers • Does not consider new ED processes (RAZ)

17. Conclusion Simulation modeling using real patient arrival and departure data suggests that diverting less urgent patients to non-ED settings will have minimal impact on patient access to ED care, while reducing ED LOS (boarding times) for admitted patients will have a large impact