Abstract 12181: Pulmonary Embolism Outcomes After Discharge From the Emergency Department: The CVRN VTE Study

Background: Patients with acute pulmonary embolism (PE) have conventionally been hospitalized for initial management and initiation of anticoagulants. However, recently developed risk scores have been able to identify patients at low risk for poor PE outcomes. We compared short-term outcomes of patients with acute PE discharged from the emergency department (ED) compared to hospitalized patients with PE. METHODS: We used electronic databases from Kaiser Permanente Northern California, an integrated healthcare delivery system, from January 1, 2004 to December 31, 2010. We identified patients aged ≥ 21 years discharged with an incident primary diagnosis code of PE during an ED visit or inpatient hospitalization, and who were prescribed anticoagulants within 7 days of discharge. We excluded patients with prior venous thromboembolism diagnoses or prior anticoagulant prescriptions. Clinical, utilization, and mortality data were obtained from automated clinical databases. We compared 30-day mortality and readmission rates between ED and hospitalized patients with PE using multivariable logistic regression RESULTS: We identified 4598 patients with a primary diagnosis of PE who were discharged on anticoagulants. The majority, 4325 (94%), were hospitalized and 292 (6.3%) were discharged from the ED. Hospitalized patients with PE were on average older (age 63.7 vs. 61.5, p=0.05) and more likely to have at least one risk factor for worse outcome after PE (age > 80, history of cancer, or cardiopulmonary disease): 62.6% vs. 55.8%, p=0.02. ED patients had somewhat lower 30-day mortality compared to hospitalized patients (0.7% vs. 2.4%, p=0.06), and significantly lower 30-day readmission rates (11% vs. 23%, p≤0.01). After adjusting for age, sex, and comorbid conditions, there was no significant difference in 30-day mortality between ED and hospitalized patients (adjusted odds ratio = 1.0 [0.9-1.0]), while 30-day readmission was significantly lower in ED patients (adjusted odds ratio = 0.9 [0.8-0.9]). Conclusions: Approximately 1 in 16 patients with acute PE were safely discharged directly from the ED. This suggests that a subgroup of patients identified as lower risk with PE may be managed as outpatients.