Triage guidelines for emergency heart patients studied

Aug 30 2007

Two new studies led by researchers at the University of Iowa and the Department of Veterans Affairs Iowa City Health Care System provide reassuring findings for patients evaluated in the emergency room for possible acute coronary syndrome (ACS) and the physicians who treat them.

ACS is a medical term for a group of potentially life-threatening heart conditions including unstable angina and heart attack. Chest pain, shortness of breath and nausea are symptoms of possible ACS, and almost five million Americans are seen each year in emergency rooms with these symptoms. In such cases, emergency room physicians must determine which patients should be admitted for more tests and observation and which patients can be discharged safely. Among those requiring hospitalization, physicians must also decide if the patient needs to be admitted to a specialty cardiology bed.

One study, published in July 19 online issue of Medical Decision Making, finds that patients who were triaged in accordance with standard guidelines for management of possible ACS tended to do better than those who were not.

These triage guidelines are based on the best available evidence and expert opinion and are used to varying degrees. However, treating physicians may choose to deviate from the guidelines recommendations at their discretion.

"It is often assumed that practice guidelines are having the desired effect on clinical care, but without taking a closer look at the data we don't really know if that is the case," said David Katz, M.D., associate professor of internal medicine in the UI Roy J. and Lucille A. Carver College of Medicine, and epidemiology in the UI College of Public Health.

The second study, published online Aug. 29 in the Annals of Emergency Medicine, found that patients with suspected ACS who are admitted to the hospital from the emergency department have similar outcomes whether they are admitted to cardiology units or non-cardiology units.

For the first study, Katz and his colleagues investigated the safety and utility of the Agency for Health Care Policy and Research (AHCPR) Unstable Angina Practice Guideline, which recommend discharge of low-risk patients and admission of intermediate- to high-risk patients to a monitored bed. Using medical records from 7,466 adults who came to the emergency departments with symptoms of possible ACS and who participated in three clinical effectiveness trials during 1993-2001, the research team used the guidelines to divide the patients into two groups -- low-risk and intermediate- to high-risk. They then compared outcomes for patients who were treated in accordance with the AHCPR triage guidelines against those who were not.

"Our analysis was reassuring in the sense that low-risk patients who were triaged based on the guideline recommendations had similar outcomes as those who were admitted. Discharge was not associated with a higher risk of death and did not increase the need for emergency care or hospitalization during 30-day follow-up in low-risk patients," said Katz, who also is a staff physician and researcher with the VA Iowa City Health Care System and its Center for Research in the Implementation of Innovative Strategies and Practices (CRIISP), and lead author of both studies.

"Among the intermediate- to high-risk group, we determined that those who were admitted were less likely to revisit the emergency room within 30 days, but otherwise the outcomes were similar to patients who were not triaged in agreement with the guidelines," he added.

Katz did sound a note of caution regarding discharge of low-risk patients. Although discharge did not lead to adverse consequences, about 2 percent of these patients subsequently were found to have ACS. This is similar to what has been shown in previous studies. Katz and his colleagues suggest that the finding demonstrates the need for special precautions such as arranging timely follow-up clinic visits for discharged low-risk patients or performing additional diagnostic studies in the emergency department prior to discharge.

The second study examined a subgroup of patients who had been admitted to the hospital for evaluation of possible ACS. Of these 544 patients, 372 were admitted to cardiology and 172 were admitted to non-cardiology units. The researchers assessed whether patients received recommended therapy in the emergency department and during hospitalization; patients were also assessed in terms of 30-day outcome. Although the cardiology patients received more aggressive testing and treatment than the non-cardiology patients, the overall outcomes were very similar.

"Emergency physicians and patients admitted for evaluation of possible ACS should be reassured that the patients do not receive inferior care if they are initially admitted to a non-cardiology service," Katz said.