What criteria should be used to decide whether to send a newly diagnosed pulmonary embolism (PE) patient to the emergency room (ER) or manage them as an outpatient?

Deciding Between ER Transfer vs. Outpatient Management for Newly Diagnosed PE

Use validated risk stratification tools (PESI/sPESI or Hestia criteria) combined with mandatory exclusion criteria to determine disposition—patients with sPESI score of 0 or PESI class I/II who meet no exclusion criteria can be safely managed outpatient with appropriate infrastructure in place. 1, 2

Step 1: Apply Risk Stratification Tools

Start with one of these validated approaches:

• Simplified PESI (sPESI): Score of 0 indicates low risk with 30-day mortality of approximately 1.0-1.1% 2
• PESI Score: Class I/II indicates low risk with 30-day mortality ≤1.6% and 3.6% respectively 2
• Hestia Criteria: A pragmatic exclusion checklist that identifies patients unsuitable for outpatient care 2

If the patient scores as low-risk by these tools, proceed to Step 2. If intermediate or high-risk, send to ER. 1

Step 2: Screen for Mandatory Exclusion Criteria

Hemodynamic Instability (Any of these → ER)

• Heart rate >110 bpm 1, 2
• Systolic blood pressure <100 mmHg 1, 2
• Oxygen saturation <90% on room air 1, 2
• Requirement for inotropes, critical care, thrombolysis, or embolectomy 1

Active Bleeding or High Bleeding Risk (Any of these → ER)

• Recent gastrointestinal bleed or surgery 1, 2
• Previous intracranial bleeding 1
• Uncontrolled hypertension 1
• Severe thrombocytopenia 2

Medical Contraindications (Any of these → ER)

• Already on full-dose anticoagulation at time of PE diagnosis 1, 3
• Chronic kidney disease stage 4 or 5 (eGFR <30 mL/min) 1, 3
• Severe liver disease 1, 3
• Heparin-induced thrombocytopenia within the last year where heparin is the only option 1
• Severe pain requiring opiates 1, 2
• Other medical comorbidities requiring hospital admission 1

Social and Logistical Factors (Any of these → ER)

• Inability to return home or inadequate home care 1, 2
• Lack of telephone communication 1, 2
• Concerns about medication compliance 1, 2
• Patient does not feel well enough to go home 2

Step 3: Verify Required Infrastructure Exists

Do not attempt outpatient management unless ALL of these are in place:

• Consultant or senior clinician (ST3+ or equivalent) review before discharge 1, 2
• Same-day access to anticoagulation medications (preferably DOACs like apixaban or rivaroxaban) 2, 3
• 24-hour emergency contact number and written instructions for readmission 1
• Formal review (telephone or face-to-face) at least once during the first week after discharge 1, 2
• Robust local protocol for follow-up and monitoring 2

Step 4: Consider Additional Risk Markers (Optional Refinement)

If RV dilation is present on CT or echocardiography in an otherwise low-risk patient:

• Measure cardiac biomarkers (BNP, NT-proBNP, or high-sensitivity troponin) 1, 2
• Normal biomarkers → can proceed with outpatient management 1
• Elevated biomarkers → admit for observation 1

Important caveat: Do not use RV dilation alone to exclude patients from outpatient management—biomarkers provide additional stratification. 2

Common Pitfalls to Avoid

• Don't skip risk stratification: Using clinical gestalt alone without validated tools increases misclassification risk 1, 2
• Don't perform routine bleeding risk scores beyond the exclusion criteria listed above in patients deemed low-risk by PESI/sPESI/Hestia 1, 2
• Don't discharge without same-day anticoagulation: Patients must leave with medication in hand, not prescriptions to fill later 2
• Don't use PESI/sPESI in pregnant patients: These scores are not validated in pregnancy—all pregnant patients with PE should have consultant review and discussion with maternity services 1

Evidence Supporting Safety of Outpatient Management

When properly selected, outpatient management demonstrates excellent safety:

• 90-day recurrent VTE rate: 0.6% 1
• 90-day major bleeding rate: 0.6% 1
• 90-day all-cause mortality: 0.6% 1
• VTE-related and hemorrhage-related mortality: 0% (upper 95% CI 0.62%) 4

These outcomes are non-inferior to inpatient management when appropriate selection criteria are applied. 1, 4

Anticoagulation Choice for Outpatients

Prefer direct oral anticoagulants (DOACs) as first-line therapy:

• Apixaban or rivaroxaban: Single-drug regimen, no bridging required 1, 2, 3
• Dabigatran or edoxaban: Require initial LMWH bridging 1, 2

DOACs eliminate INR monitoring needs and facilitate early discharge compared to warfarin. 3

Special Consideration: Early Discharge for Initially Admitted Patients

Patients admitted with intermediate-risk PE (PESI class III) can be considered for early discharge when they meet low-risk criteria (PESI class I/II or sPESI score 0) within 48 hours, though senior review is necessary before discharge. 1