Which scoring system can help identify low-risk Venous Thromboembolism (VTE) patients suitable for outpatient management?

Pulmonary Embolism Severity Index (PESI) is the Optimal Scoring System for Identifying Low-Risk VTE Patients for Outpatient Management

The Pulmonary Embolism Severity Index (PESI) or its simplified version (sPESI) is the most validated and reliable scoring system to identify low-risk VTE patients suitable for outpatient management. 1

Comparison of Risk Stratification Tools

PESI Score

• Most extensively validated scoring system for PE risk stratification
• Classifies patients into five risk classes (I-V)
• PESI class I (very low risk) and II (low risk) patients have 30-day mortality rates of ≤1.6% and 3.6%, respectively 1
• Excellent discrimination with AUC of 0.77-0.87 in validation studies 1
• Identifies approximately 49% of PE patients as low-risk candidates for outpatient management 2

Simplified PESI (sPESI)

• Streamlined version of PESI with only 6 variables:
  • Age >80 years (1 point)
  • Cancer (1 point)
  • Chronic cardiopulmonary disease (1 point)
  • Pulse ≥110 bpm (1 point)
  • Systolic blood pressure <100 mmHg (1 point)
  • Oxygen saturation <90% (1 point)
• Score of 0 = low risk; ≥1 = higher risk
• Identifies approximately 22-33% of PE patients as low-risk 3
• 30-day mortality in low-risk patients is only 0.5-1.0% 3
• Non-inferior to original PESI in predicting outcomes 1

Other Scoring Systems in the Question

1. CHAD2DS2-VASc score: Designed to assess stroke risk in atrial fibrillation, not for VTE risk stratification

2. Pulmonary Embolism Rule-Out Criteria (PERC): Used to rule out PE in low-risk patients with suspected PE, not to risk-stratify confirmed PE cases for outpatient management

3. Wells Criteria: Used to determine pre-test probability of PE in patients with suspected PE, not for risk stratification after PE diagnosis

Evidence Supporting PESI/sPESI for Outpatient Management

• British Thoracic Society guidelines specifically recommend PESI or sPESI for identifying low-risk PE patients suitable for outpatient management (Grade B recommendation) 1, 4

• Mayo Clinic Proceedings confirms that the simplified PESI is "an easy-to-use risk stratification tool to help discern which patients with PE may be treated as outpatients" 1

• Low-risk patients identified by PESI/sPESI have:

  • Very low 30-day mortality (0.5-1.1%) 3
  • Low rates of recurrent VTE (1.3%) 3
  • Low rates of major bleeding (1.1%) 3

• Recent studies show that 33.7-49.7% of PE admissions could potentially be managed as outpatients based on PESI/sPESI risk stratification 2

Implementation in Clinical Practice

• Electronic health record-based automated PESI calculators have been developed to facilitate real-time risk assessment in emergency departments, with 95.4% accuracy in distinguishing low vs. high-risk patients 5

• For patients initially admitted with intermediate risk (PESI class III), reassessment at 48 hours can identify those who have improved to low risk (PESI class I/II) and may be candidates for early discharge 1

Common Pitfalls to Avoid

• Failing to use validated risk assessment tools like PESI/sPESI when determining disposition for PE patients
• Not considering social factors that might affect outpatient management success
• Inadequate follow-up planning for outpatients
• Not reassessing initially higher-risk patients who may become eligible for early discharge

Algorithm for PE Outpatient Management Decision-Making

1. Calculate PESI or sPESI score for all hemodynamically stable PE patients
2. If PESI class I-II or sPESI = 0, assess for exclusion criteria:
   • Oxygen saturation <90%
   • Systolic BP <100 mmHg
   • Active bleeding or high bleeding risk
   • Need for opiates for pain control
   • Severe renal failure (CrCl <30 mL/min)
   • Social barriers to treatment adherence or follow-up
3. If no exclusion criteria, initiate outpatient management with appropriate anticoagulation (preferably DOAC)
4. Ensure robust follow-up pathway with scheduled appointment within 1-2 weeks

By systematically applying the PESI or sPESI scoring system, clinicians can confidently identify low-risk PE patients who can be safely managed as outpatients, reducing unnecessary hospitalizations while maintaining excellent outcomes.