Rerouting ambulances away from overcrowded emergency departments is linked to a 3 percent higher risk of death in heart attack patients, according to a new study published in the Journal of the American Medical Association (JAMA). ‘Now we actually have empirical evidence to show crowding affects patients in a very real way,’ said lead study author, Dr. Renee Hsia, an emergency physician at the University of California, San Francisco in a Reuters article.

Researchers surveyed nearly 14,000 Medicare patients with acute myocardial infarction and 149 emergency departments in California between 2000 and 2005 and found that patients who were diverted for at least 12 hours by the nearest ED were associated with increased mortality (30-day, 90-day, 9-month, and 1-year).

Ambulance diversion is a practice in which hospitals temporarily close off services to new patients typically because their emergency department is already filled to capacity and/or limited staffing reasons. In 2009, Massachusetts was the first state to issue a ban on ambulance diversion. Early reports showed that the ban has not negatively affected patient waiting times, according to the study.

Researchers concluded that ambulance diversion does not only affect the diverted patients but also patients receiving care while the ED is on diversion status […]