Ambulance diversion is not associated with low acuity patients attending Perth metropolitan emergency departments

To examine the relationship between ambulance diversion and low acuity patient (LAP) attendances to EDs.

Comparison of LAP attendance rates at inner metropolitan EDs and outer metropolitan EDs using a previously validated methodology.

The percentage of LAP attendances was lower at inner metropolitan EDs (11.4%, 95% CI 11.3-11.6) compared to outer metropolitan hospitals (22.9%, 95% CI 22.6-23.2, P < 0.001). The proportion of LAP attendances was slightly higher at both inner and outer metropolitan hospitals after-hours compared to working hours. Average daily LAP attendances per inner metropolitan hospital (13.4 attendances, 95% CI 13.2-13.6) which averaged 89.2 min of diversion daily (95% CI 88.7-89.7) were lower than at outer metropolitan hospitals (19.3 attendances, 95% CI 19.0-19.6, P < 0.001), which averaged 12.4 min of diversion daily (95% CI 12.1-12.5, P < 0.001).

Inner metropolitan hospitals experience low LAP attendance rates. Attempts to further reduce LAP attendance rates at Perth inner metropolitan hospitals have limited scope to reduce ambulance diversion.