How is a patient's management guided by their Pulmonary Embolism (PE) score?

Management of Pulmonary Embolism Based on PE Score

Low-risk PE patients (PESI Class I/II or sPESI=0) should be managed as outpatients with direct oral anticoagulants (apixaban or rivaroxaban), while intermediate-risk patients (PESI Class III or higher) require inpatient management with standard anticoagulation and close monitoring, and high-risk patients (hemodynamically unstable) need immediate inpatient management with consideration of thrombolytic therapy. 1, 2

Risk Stratification Framework

The PESI score stratifies patients into five classes (I-V) based on 11 clinical variables including age, vital signs, comorbidities, and clinical findings. 3, 2 The score demonstrates excellent discriminatory power with area under the ROC curve of 0.77-0.87 for predicting 30-day mortality. 3, 2

Key mortality rates by PESI class:

• Class I (very low risk): ≤1.6% 30-day mortality 3, 2
• Class II (low risk): 3.6% 30-day mortality 3, 2
• Classes III-V (intermediate to high risk): 7.1% to 23.9% 30-day mortality 3

The simplified PESI (sPESI) uses six binary variables (age >80, cancer, chronic cardiopulmonary disease, pulse ≥110, systolic BP <100, oxygen saturation <90%), with a score of 0 identifying low-risk patients with 30-day mortality of 1.0-1.1%. 3, 1

Management Algorithm by Risk Category

Low-Risk Patients (PESI I/II or sPESI=0)

Outpatient management is appropriate when exclusion criteria are absent. 1, 2 Mandatory exclusion criteria include: physiologic instability, active bleeding or recent major bleeding risk, severe renal impairment, and social factors precluding safe discharge. 1

Anticoagulation options for outpatient management:

• Single-drug regimens: apixaban or rivaroxaban (preferred, no LMWH lead-in required) 1, 2
• LMWH bridge regimens: LMWH plus dabigatran or LMWH plus edoxaban 2

Critical implementation requirements:

• Same-day anticoagulation initiation before discharge 1
• Consultant or senior clinician review before discharge 2
• Robust pathway for follow-up and monitoring 3, 2
• Same-day investigation ideally completed 2

Intermediate-Risk Patients (PESI III or Higher with sPESI ≥1)

Inpatient management with standard anticoagulation and close monitoring is required. 1, 4 These patients need further stratification based on right ventricular dysfunction and cardiac biomarkers. 1

Initial anticoagulation strategy:

• Start anticoagulation immediately without waiting for complete diagnostic confirmation 4
• Use LMWH or fondaparinux for most intermediate-risk patients 4
• Reserve unfractionated heparin for high bleeding risk or severe renal dysfunction 4

Transition to oral anticoagulation:

• DOACs (apixaban, dabigatran, edoxaban, rivaroxaban) strongly preferred over vitamin K antagonists 4
• Apixaban and rivaroxaban offer single-drug regimens without LMWH lead-in 4
• Dabigatran and edoxaban require initial parenteral anticoagulation before transitioning 4

Monitoring and escalation:

• Close monitoring for clinical deterioration with assessment of RV function by imaging or biomarkers 4
• Routine primary thrombolysis is NOT recommended for stable intermediate-risk PE 4
• Rescue thrombolytic therapy is strongly recommended if hemodynamic deterioration develops despite anticoagulation 4
• Recalculate PESI at 48 hours (PESI-48) to identify candidates for early discharge 4

Hemodynamic support if needed:

• Supplemental oxygen for hypoxemia (SaO2 <90%), but avoid aggressive fluid challenges which may worsen RV failure 4
• Vasopressor support with norepinephrine and/or dobutamine if hemodynamic compromise develops, signaling need for rescue thrombolysis 4

High-Risk Patients (Hemodynamically Unstable)

Immediate inpatient management with consideration of thrombolytic therapy is required. 3, 1 Overwhelming consensus supports treating hemodynamically unstable patients with confirmed PE when benefits outweigh risks. 3

Critical Exceptions and Nuances

Right heart thrombus represents a critical exception where anatomic location significantly impacts prognosis, with mortality of 21% versus 11% without right heart thrombi. 1 Thrombolytic therapy is the only treatment independently associated with decreased mortality in this subset. 1

Concomitant DVT is an adverse prognostic factor independently associated with 30-day all-cause mortality (OR 1.9,95% CI 1.5-2.4). 1

Additional biomarkers for risk refinement:

• High-sensitivity troponin and sPESI combination may identify extremely low-risk patients (0% complicated outcomes when both sPESI=0 and hsTnT <14 pg/mL) 3
• However, sPESI alone had 100% negative predictive value in some cohorts, so adding hsTnT may not improve identification of very low-risk patients 3

Common Pitfalls to Avoid

Do not rely solely on RV dilation on imaging to exclude patients from outpatient management. 1 If RV dilation is present, measure cardiac biomarkers (BNP/troponin) for additional risk stratification. 1

Do not use routine bleeding risk scores beyond the exclusion criteria already outlined for patients deemed low-risk by PESI/sPESI. 1

Do not discharge patients without same-day anticoagulation. 1

Do not delay anticoagulation while awaiting complete diagnostic confirmation in intermediate-risk patients. 4

Do not prescribe DOACs to patients with severe renal impairment, pregnancy, or antiphospholipid syndrome. 4

Do not use routine thrombolysis in stable intermediate-risk patients, as bleeding risk outweighs benefit. 4