A structured, computer-order algorithm for emergency department chest pain patients reduces missed diagnoses of acute coronary syndrome and decreases admission rate

Introduction: Many emergency departments (ED) utilize unstructured, individualized approaches to patients with chest pain. Estimates of the rate of missed diagnoses of acute coronary syndrome (ACS) range from 2% to 5%. We sought to reduce this rate by developing an algorithm that would provide a structured approach in managing chest pain patients. Methods: A formalized ED chest pain evaluation process was developed and provided to emergency physicians (EP). The elements were encouraged but not mandatory and included computer-order entry that prompted EKGs and cardiac biomarkers on ED arrival and 6 hours later and facilitated scheduling of outpatient stress EKGs or radionuclide scans within 48 hours for patients with no objective ischemia. Patients felt to be at clinical risk or those with positive tests were referred to cardiology. At the EPs discretion, very low-risk patients could be discharged before 6 hours. A single-centre cohort of chest pain patients enrolled in 2006 was compared with a historical unstructured cohort from the same site from June 2000 to April 2001. The primary outcome was the rate of missed diagnosis of ACS at 30 days, defined as discharge from the ED with a non-ACS diagnosis but a subsequent ACS event within 30 days. Results: Both groups were similar in age, gender, and vital signs. ACS prevalence was 21.2% (398/1819) in the historic and 11.1% (124/1117) in the intervention cohort. The 30-day missed ACS rate fell from 5.3% (21/398) to 0% (0/124). The admission rate for patients with no ACS decreased from 18.3% to 6.7%, and similar proportions (21.2% v. 19.8%) of patients were discharged from the ED within 3 hours. Five patients died in each group, and the rates of coronary interventions were 11.7% and 6.8%, respectively. Conclusion: In a cohort of ED patients with undifferentiated chest pain, the intervention protocol resulted a reduction in the 30-day missed ACS rate, while decreasing admissions. Keywords: acute coronary syndromes, computerized physician order entry, diagnostic error