Diverting Patients Away From Crowded EDs Tied to Higher Mortality Rates

High levels of ambulance diversion -- which occurs when overcrowded emergency departments temporarily close to traffic -- are associated with a 3% higher risk of death among patients experiencing heart attacks, according to a study published in the Journal of the American Medical Association, HealthDay/USA Today reports (Preidt, HealthDay/USA Today, 6/13).

Ambulance diversion is a common tactic used to reduce ED overcrowding. In the U.S., one ambulance is rerouted away from the nearest hospital every minute, according to the National Center for Health Statistics (Joelving, Reuters, 6/13).

For the study, Renee Hsia of UC-San Francisco and other researchers examined data from 2000 to 2005 for 13,860 Medicare beneficiaries who were admitted to EDs for heart attack symptoms in one of four California counties: Los Angeles, San Francisco, San Mateo or Santa Clara. Within each hospital, they compared death rates across varying levels of ED crowding.

Key Findings

According to the study, ambulance traffic on average was rerouted from the nearest ED to another hospital about 7.9 hours daily.

Researchers also found that patients whose nearest ED diverted ambulances for 12 hours or more had a death rate of 19% after one month, compared with a 15% death rate among those who received care at the nearest hospital.

The gap persisted after three months, nine months and one year (HealthDay/USA Today, 6/13).

Conclusions

The study authors noted that the evidence was inconclusive and proved only an "association" between higher death rates and ambulance diversion (Reuters, 6/13).

Researchers also suggested that targeted interventions are needed to adequately distribute resources to decrease ED overcrowding and ambulance diversion, so patients are not adversely affected (HealthDay/USA Today, 6/13).