What is the initial approach for managing pulmonary embolism (PE)?

Initial Management of Pulmonary Embolism

The initial approach for managing pulmonary embolism (PE) should include risk stratification using validated clinical scores (PESI, sPESI, or Hestia criteria), followed by appropriate anticoagulation and determination of treatment setting based on risk assessment. 1

Risk Stratification

Risk stratification is essential to determine the appropriate treatment setting and intensity:

1. Use validated clinical risk scores:

   • Pulmonary Embolism Severity Index (PESI)
   • Simplified PESI (sPESI)
   • Hestia criteria

2. Risk categories:

   • Low risk: PESI class I/II, sPESI 0, or meeting Hestia criteria
   • Intermediate risk: PESI class III or higher, sPESI ≥1
   • High risk: Hemodynamically unstable (SBP <100 mmHg, HR >110 bpm)

Exclusion Criteria for Outpatient Management

Even if low-risk by scoring systems, patients should be hospitalized if any of these are present 1:

• Hemodynamic instability (HR >110 bpm, SBP <100 mmHg)
• Oxygen saturations <90% on room air
• Active bleeding or high bleeding risk
• Already on full-dose anticoagulation
• Severe pain requiring opiates
• Medical comorbidities requiring admission
• Severe renal or liver disease
• History of HIT within past year
• Social factors limiting home care

Anticoagulation Therapy

1. For hemodynamically stable patients:

   • Direct oral anticoagulants (DOACs) are preferred first-line:
     • Apixaban: 10 mg BID for 7 days, then 5 mg BID
     • Rivaroxaban: 15 mg BID for 21 days, then 20 mg daily
     • Dabigatran: After 5 days of LMWH, 150 mg BID
     • Edoxaban: After 5 days of LMWH, 60 mg daily

2. For hemodynamically unstable patients:

   • Intravenous unfractionated heparin (UFH) is preferred:
     • Initial bolus: 80 IU/kg
     • Maintenance: 18 IU/kg/hour
     • Adjust to maintain APTT 1.5-2.5× control

3. For patients with cancer:

   • Traditionally LMWH was preferred, but recent evidence supports DOACs in most cancer patients 2

Treatment Setting Decision

1. Outpatient management for low-risk patients (PESI I/II or sPESI 0) without exclusion criteria 1

   • Ensure robust follow-up pathway exists
   • Patient must be able to understand treatment and return if symptoms worsen
   • Provide clear instructions and emergency contact information

2. Inpatient management for:

   • Intermediate or high-risk patients
   • Patients with any exclusion criteria for outpatient management
   • Patients with RV dysfunction or elevated cardiac biomarkers

Special Considerations

1. Hemodynamically unstable patients:

   • Consider thrombolysis, surgical embolectomy, or catheter-directed interventions 1
   • Apixaban is not recommended as initial treatment for hemodynamically unstable PE patients 3

2. Right ventricular dysfunction:

   • If RV dilatation is identified on imaging in otherwise low-risk patients, consider measuring cardiac biomarkers (BNP, NT-proBNP, hsTnI or hsTnT)
   • Normal biomarkers may allow outpatient management
   • Elevated biomarkers should prompt inpatient observation 1

3. Early discharge consideration:

   • Patients initially admitted with intermediate risk (PESI class III) can be considered for early discharge when they improve to low risk (PESI class I/II or sPESI 0) 1

Common Pitfalls to Avoid

1. Missing PE diagnosis in:

   • Elderly patients
   • Patients with severe cardiorespiratory disease
   • Patients with isolated dyspnea without other symptoms 1

2. Inappropriate outpatient management of patients with:

   • Elevated cardiac biomarkers
   • RV dysfunction without biomarker assessment
   • Social factors limiting adherence to treatment

3. Inadequate anticoagulation monitoring:

   • For patients on heparin, check APTT 4-6 hours after initial bolus
   • After dose changes, recheck APTT 6-10 hours later
   • For stable patients on therapeutic anticoagulation, monitor daily 1

By following this structured approach to PE management, clinicians can ensure appropriate risk stratification, treatment setting decisions, and anticoagulation therapy to optimize patient outcomes and reduce mortality.