Safety of outpatient treatment in acute pulmonary embolism

Introduction: Data regarding outpatient treatment of pulmonary embolism (PE) is scarce. This study evaluates the safety of outpatient management of acute PE. Methods: This is a retrospective cohort study of consecutive patients presenting at the Ottawa Hospital with acute PE diagnosed between 1 January 2007 and 31 December 2008. PE was defined as an arterial filling defect on CTPA or a high probability V/Q scan. Patients were managed as outpatients if they were hemodynamically stable, did not require supplemental oxygenation and did not have contraindications to low-molecular-weight heparin therapy. Results: In this cohort of 473 patients with acute PE, 260 (55.0%) were treated as outpatients and 213 (45.0%) were admitted to the hospital. The majority of the patients were admitted because of severe comorbidities (45.5%) or hypoxia (22.1%). No outpatient died of fatal PE during the 3-month follow-up period. At the end of follow-up, the overall mortality was 5.0% (95% CI, 2.7-8.4%). The rates of recurrent venous thromboembolism (VTE) in outpatients were 0.4% (95% CI, 0.0-2.1%) and 3.8% (95% CI, 1.9-7.0%) within 14 days and 3 months, respectively. The rates of major bleeding episodes were 0% (95% CI, 0-1.4%) and 1.5% (95% CI, 0.4-3.9%) within 14 days and 3 months, respectively. Four (1.5%) outpatients were admitted to the hospital within 14 days. Conclusions: A majority of patients with acute PE can be managed as outpatients with a low risk of mortality, recurrent VTE and major bleeding episodes.