Study: Who uses an ambulance?

By Art Hsieh, EMS1 Editorial Advisor

During the past decade, ambulance diversion from overcrowded emergency departments and hospitals has been a great topic of discussion among EMS personnel. Many providers have been diverted from their original receiving hospitals; there have been cases where an ambulance may spend more than an hour on the road “searching” for an open emergency department, changing directions multiple times as hospitals opened and closed their doors to ambulance traffic.

Researchers from Harbor-UCLA Medical Center and UC Berkeley School of Public Health looked at which patients may be most impacted by these diversions. Using a national database they looked at the demographics of 30,000 patients who were transported by ambulance and studied whether “at risk” populations of the elderly, the uninsured, and racial/ethnic populations, and the critically ill, disproportionately utilized ambulance transport as compared to the general population. They found several key data points:

1. The association between race/ethnicity and ambulance usage was not significant. In another words, patients from an ethnic minority background were not more likely to use an ambulance transport as compared to Caucasian patients.
2. Among critically ill patients, Latinos were slightly less likely to use an ambulance when compared to other ethnic groups. Possible explanations for lower ambulance utilization
   by Latinos, according to the researchers, are decreased awareness of availability of emergency services, concerns over ambulance bills, or fear of deportation among undocumented residents.
3. Patients covered by Medicare were far more likely to use an ambulance as compared to those patients covered by private insurance.
4. Calls for ambulance transport rose with the age of the patients studied. This points to increasing demand for EMS as our nation’s population continues to age. The proportion of U.S. residents aged 65 years and older is expected to increase from 12 percent in 2006 to 16 percent in 2020, according to the study, and the need for ambulance transport can be expected to increase concomitantly. The increasing demands on ambulance transport and EDs from an aging population indicate that ambulance diversion is likely to worsen and the elderly will be most affected, the researchers said.
5. Patients with critical conditions, as defined by the study were more likely to use an ambulance than those with noncritical conditions.
6. Nearly 50 percent of critical ill patients did not use an ambulance for transport. This is remarkably similar to the statistic regarding patients experiencing heart attacks.

There are several implications to this study. First, ambulance diversion may disproportionately impact several subgroups of the population, namely patients with Medicare insurance or public insurance, the uninsured, the elderly, and the critically ill disproportionately. As the authors point out, this requires more study.

Second, there is no information that indicates whether critically ill patients may be positively or negatively impacted by ambulance diversion.

Finally, barely half of critically ill patients call for an ambulance, when they need it the most. We can help increase this number through better community outreach and educational efforts.