Low-Risk Pulmonary Embolism Management

Introduction to Outpatient Management

The American College of Chest Physicians recommends outpatient treatment for patients with low-risk pulmonary embolism, provided they meet specific eligibility criteria and have access to appropriate follow-up care, with a strong recommendation despite low certainty of evidence 1

The European Respiratory Society and other guidelines suggest using PESI (Pulmonary Embolism Severity Index) class I/II, with 30-day mortality rates of ≤1.6% and 3.6% respectively, for risk stratification 4
The British Thoracic Society recommends using simplified PESI (sPESI) score of 0, with 30-day mortality of approximately 1.0-1.1%, for risk stratification 4
The European Respiratory Society suggests using Hestia criteria, a pragmatic list of exclusion criteria, for risk stratification 2, 3

Patients must not have physiologic instability, including heart rate >110 bpm, systolic blood pressure <100 mmHg, oxygen saturation <90% on room air, or severe pain requiring opiates, to be eligible for outpatient treatment 2, 3
Patients must not have medical contraindications, including active bleeding or recent major bleeding risk, already on full-dose anticoagulation, severe renal failure, severe liver disease, or severe thrombocytopenia, to be eligible for outpatient treatment 2, 3, 5
Patients must not have social and logistical factors, including inability to return home or inadequate home care, lack of telephone communication, concerns about medication compliance, or patient does not feel well enough to go home, to be eligible for outpatient treatment 2, 3, 5

A robust pathway for follow-up and monitoring must exist, with access to prompt outpatient care if symptoms worsen, consultant or senior clinician review before discharge, and access to medications, including anticoagulation, for safe outpatient management 1, 2, 5

Outpatient management has been shown to have similar 90-day all-cause mortality, major bleeding, and recurrent PE rates compared to inpatient management, with no difference in outcomes 1
A landmark randomized controlled trial demonstrated that among 171 outpatients with low-risk PE, only 0.6% developed recurrent VTE within 90 days, with mean hospital stay of just 0.5 days compared to 3.9 days for inpatients 1

Direct oral anticoagulants (DOACs), such as apixaban or rivaroxaban, are recommended as first-line therapy for outpatient treatment of low-risk PE, with a strong recommendation and moderate-certainty evidence showing similar efficacy but improved safety profile 1
Dabigatran or edoxaban may also be used, but require initial LMWH bridging 1, 4

Do not rely solely on imaging findings, such as RV dilation on CT or echocardiography, to exclude patients from outpatient management, but consider measuring cardiac biomarkers (BNP/troponin) for additional risk stratification if RV dilation is present 2, 3
Do not perform routine bleeding risk scores beyond the exclusion criteria in patients deemed low-risk by PESI/sPESI/Hestia 2, 3
Do not discharge patients without same-day anticoagulation, with immediate access to anticoagulation medications before leaving the emergency department 1, 4