Important data sources and applications of ED measures and how they can impact the practice of emergency medicine
As emergency department leaders, it is critical that emergency physicians understand the national data sources available to improve the local emergency system and the functions of the department. This column will review the most important sources and applications of ED performance measures and how they should impact the practice of emergency medicine, including your personal practice. These critical data elements are important for all emergency physicians as discussions evolve regarding the value of emergency care with hospital leaders, community decision makers, and the designers of the future health system.
ED Performance Focused Data Sources
The Emergency Department Benchmarking Alliance (EDBA), founded in 1994, has 20 years of experience in defining ED performance measures, cohorts, and mechanisms for improving the management of EDs. The EDBA annual data survey produces a small number of well-defined performance measures and descriptive elements of the ED. The alliance now comprises 1,000 EDs from every state, and every volume and acuity, that serve 40 million patients. Emergency physicians can find trends in performance measures related to ED size, flow, acuity, disposition, productivity, use of diagnostic tools, and space utilization.
The Centers for Disease Control and Prevention (CDC) initiated a study in 1992 to investigate the types of patients being served in EDs, their medical characteristics, and the disposition of the patients at the end of the visit. The National Hospital Ambulatory Medical Care Survey (NHAMCS) is a wealth of information on emergency medicine in America. The CDC sampling and analysis process takes some time, so the latest available is the 2010 data report, which is based on a sampling of 34,936 ED patient-care reports from 357 EDs. National population census data are used to estimate utilization of ED services by populations. The survey has almost 20 years of annual data, which have been used to identify important trends for emergency physicians and regulatory leaders.
The surveys collectively report on the success of 50 years of prevention programs to which emergency physicians have made tremendous contributions. There has been little recognition of the success in preventing premature death related to trauma, burns, and cardiac arrest. The surveys make it apparent that prevention is working in the emergency population, with ED visits related to injuries continuing to shrink. These now represent about 29 percent of ED patient encounters.
EDs are serving more high-acuity patients and more patients who are arriving in an ambulance. The combined effects of these trends are that ED visits have increased over 12 years from 369 visits per 1,000 population to 428 per 1,000. There is no indicator that points to decreased utilization of emergency services. The ED population is aging, which is in line with the demographics of the country. The ED visit rate for persons older than 65 is much higher than for those younger than 65. As this population group is going to boom for years, emergency physicians must plan for higher ED volumes and design departments that are friendlier to a senior population.
A significant increase in ED utilization is also occurring for patients with mental health and chemical use presentations. The NHAMCS report is finding an increased number of patients seen for mental health reasons, and their disposition is often difficult and time consuming. An examination of the NHAMCS database reveals that about half of patient transfers from EDs are for mental health treatment. This is a significant burden on emergency physicians and the organizations that must move these patients safely between sites.
Matching the increase in acuity is the need for further hospital-based service at the end of ED visits. A growing percentage of hospital admissions are funneled through the ED. The EDBA data indicate that 68 percent of all hospital inpatients are processed through the ED. In many hospitals, especially those in community settings, the number is 80 percent or greater. Clearly, the ED is the front door to the hospital!
The growing volume of patients also reflects the position of the ED as the diagnostic center for the American medical community. The need for precision in defining patient needs has resulted in increased use of diagnostic tools in the ED, especially diagnostic imaging. The use of diagnostic testing has changed dramatically over the last 20 years, according to surveys on ED practice. Some diagnostic tests have almost completely disappeared. Arterial blood gases were used in many patients in 1992 and now have completely disappeared due to low utilization.
The use of other diagnostic tests has increased. CT scans increased in usage from about 2.4 percent of visits in 1992 to about 16 percent in 2010. The EDBA uses a different collection and reporting methodology and found that CT use, as measured by the number of CT procedures performed per 100 patients, plateaued in 2008 at about 23 procedures per 100 patients and has now decreased to about 20 CT procedures per 100 patients. Plain diagnostic X-rays, of which about 50 percent are chest X-rays, were performed on about 42 percent of patients in 1992 and have since decreased to about 35 percent in 2010.
ECG utilization has increased from a rate of 13 uses per 100 patients in 1992 to about 26 in 2010.
The most common medicine used in the ED was promethazine prior to about 2007, when it was replaced by ondansetron, which came off patent protection in 2006, dropping the cost to hospitals significantly. Both drugs were used about 12 times per 100 patients. The changeover was also boosted due to the unusual black box warning on promethazine in 2009.
As we progress to a significantly revised health care system in America, emergency physicians must be facile in their knowledge of ED performance measures and be prepared to explain the value of emergency care to the health system. This column will explain the data elements available for emergency physicians to develop the reports on high-quality and cost-efficient care provided in EDs.
James J. Augustine, MD, FACEP, is director of clinical operations at EMP in Canton, Ohio; clinical associate professor of Emergency Medicine at Wright State University in Dayton, Ohio; vice president of the Emergency Department Benchmarking Alliance; and on the ACEP Board of Directors.
- The Emergency Department Benchmarking Alliance. Information is available at: www.EDBenchmarking.org
- The calendar year 2010 Emergency Department Summary Tables are available at: http://www.cdc.gov/nchs/data/ahcd/nhamcs_emergency/2010_ed_web_tables.pdf. The CDC data tables are now published without an analysis. It is important to archive the 2007 report for use as a reference when looking at the data tables in later years. It is available at: http://www.cdc.gov/nchs/data/nhsr/nhsr026.pdf.