The Impact of Unstable Angina Guidelines in the Triage of Emergency Department Patients with Possible Acute Coronary Syndrome

OBJECTIVE: The primary aim of this study is to determine whether implementing the Agency for Health Care Policy and Research (AHCPR) Unstable Angina Practice Guideline improves emergency physician's decision making in patients with symptoms of possible acute coronary syndrome (ACS), including those for whom the diagnosis of unstable angina is uncertain. METHODS: The authors conducted a prospective guideline implementation trial with pre-post design in the emergency departments of 1 university hospital and 1 university-affiliated community teaching hospital from January 2000 to May 2001. They enrolled 1140 adults who presented with chest pain or other symptoms of possible ACS. The intervention included the following: 1) physician training in use of the AHCPR risk groups, 2) algorithm for risk stratification, and 3) group feedback. To determine how accurately physicians interpreted the guideline algorithm, the authors compared their risk ratings with actual guideline risk groups. RESULTS: No significant difference in physician triage decisions was observed between baseline and intervention periods. Analysis of physician's risk ratings during the intervention period revealed low overall concordance with actual guideline risk groups (kappa = 0.31); however, physician's risk ratings showed superior discrimination in identifying patients with confirmed ACS (receiver operating characteristic [ROC] area .81 v. .74, P = 0.008). Strict adherence to guideline recommendations would have resulted in hospitalizing 9% more non-ACS patients without lowering the rate of missed ACS. CONCLUSION: Implementation of the AHCPR guideline did not improve triage decisions in emergency department patients with possible ACS. Assessing physician triage solely based on concordance with the AHCPR guideline may not accurately reflect the quality of patient care.