What is the management of pulmonary embolism at the Respiratory Pulmonary Disease Area (RPDA)?

Management of Pulmonary Embolism

Initiate anticoagulation immediately upon suspicion of PE while diagnostic workup proceeds, unless the patient is actively bleeding or has absolute contraindications. 1

Initial Assessment and Risk Stratification

The cornerstone of PE management is rapid risk stratification based on hemodynamic stability, which determines treatment intensity and mortality risk 1, 2:

• High-risk PE: Hemodynamic instability (sustained hypotension, shock, or cardiac arrest) 1
• Intermediate-risk PE: Hemodynamically stable but with RV dysfunction and elevated cardiac biomarkers 1
• Low-risk PE: Hemodynamically stable without RV dysfunction 1

For patients presenting with hemodynamic instability, perform bedside transthoracic echocardiography immediately to differentiate high-risk PE from other acute life-threatening conditions 1

Acute Management by Risk Category

High-Risk PE (Hemodynamically Unstable)

Systemic thrombolytic therapy is the first-line treatment for high-risk PE and should be administered immediately. 1, 2

Anticoagulation:

• Initiate unfractionated heparin (UFH) without delay, including a weight-adjusted bolus injection 1
• UFH is preferred over LMWH in high-risk PE due to its rapid reversibility and shorter half-life 1

Thrombolytic regimens 1:

• rtPA: 100 mg over 2 hours, OR 0.6 mg/kg over 15 minutes (maximum 50 mg) 1
• Streptokinase: 250,000 IU loading dose over 30 minutes, followed by 100,000 IU/h over 12-24 hours 1

Hemodynamic support 3:

• Norepinephrine and/or dobutamine should be considered for vasopressor support 1, 3
• Avoid aggressive fluid challenges, as this may worsen right ventricular failure 3

Alternative reperfusion strategies when thrombolysis is contraindicated or fails 1:

• Surgical pulmonary embolectomy is recommended 1
• Percutaneous catheter-directed treatment should be considered 1
• ECMO may be considered in combination with surgical embolectomy or catheter-directed treatment for refractory circulatory collapse or cardiac arrest 1

Intermediate-Risk and Low-Risk PE (Hemodynamically Stable)

Anticoagulation strategy:

For parenteral anticoagulation, LMWH or fondaparinux is recommended over UFH for most hemodynamically stable patients. 1

For oral anticoagulation, NOACs (apixaban, dabigatran, edoxaban, or rivaroxaban) are recommended in preference to VKAs in eligible patients. 1

NOAC dosing for PE treatment 4, 5:

• Apixaban: 10 mg twice daily for 7 days, then 5 mg twice daily 4
• Rivaroxaban: 15 mg twice daily for 21 days, then 20 mg once daily 5
• Both should be taken with food for optimal absorption 4, 5

VKA alternative 1:

• When VKAs are used, overlap with parenteral anticoagulation for ≥5 days until INR reaches 2.0-3.0 for 2 consecutive days 1
• Target INR of 2.5 (range 2.0-3.0) 1

Rescue therapy for hemodynamic deterioration:

• Rescue thrombolytic therapy is recommended for patients who deteriorate hemodynamically despite anticoagulation 1
• Surgical embolectomy or catheter-directed treatment should be considered as alternatives if thrombolysis is contraindicated or fails 1

Routine systemic thrombolysis is NOT recommended in intermediate- or low-risk PE, as the PEITHO trial demonstrated increased bleeding risk without clear mortality benefit in stable patients 1

Supportive Care

Oxygen therapy 3:

• Administer supplemental oxygen to all patients with SaO2 <90% 3
• Escalate oxygen delivery as needed: conventional oxygen → high-flow nasal cannula → non-invasive ventilation 3
• Reserve invasive mechanical ventilation for extreme instability, as positive pressure may worsen RV failure 3

If intubation becomes necessary 3:

• Use tidal volumes of approximately 6 mL/kg lean body weight 3
• Keep end-inspiratory plateau pressure <30 cm H2O 3
• Apply positive end-expiratory pressure cautiously 3
• Avoid anesthetic drugs that cause hypotension 3

Duration of Anticoagulation

All patients with PE require therapeutic anticoagulation for at least 3 months. 1

After initial 3-6 months, reassess and decide on extended therapy 1:

• Discontinue after 3 months in patients with first PE secondary to a major transient/reversible risk factor (e.g., surgery) 1, 2
• Continue indefinitely in patients with recurrent VTE not related to a major transient risk factor 1
• Continue indefinitely with VKA (not NOACs) in patients with antiphospholipid antibody syndrome 1

For extended anticoagulation after ≥6 months of treatment, consider reduced-dose regimens 1:

• Apixaban 2.5 mg twice daily 1, 4
• Rivaroxaban 10 mg once daily 1, 5

Special Considerations

NOAC contraindications 1:

• Severe renal impairment (CrCl <30 mL/min for rivaroxaban; <25 mL/min for apixaban) 1
• Pregnancy and lactation 1
• Antiphospholipid antibody syndrome 1

IVC filters 1:

• Should be considered only in patients with absolute contraindications to anticoagulation 1
• Should be considered in cases of PE recurrence despite therapeutic anticoagulation 1
• Routine use is NOT recommended 1

Early discharge 1:

• Carefully selected low-risk PE patients should be considered for early discharge and home treatment if proper outpatient care can be provided 1

Follow-Up Care

Routinely re-evaluate all patients 3-6 months after acute PE 1, 2:

• Assess for signs of VTE recurrence, bleeding complications, or persistent dyspnea 1
• Screen for chronic thromboembolic pulmonary hypertension (CTEPH) in symptomatic patients 1
• Refer patients with persistent symptoms and mismatched perfusion defects to a pulmonary hypertension/CTEPH expert center 1

Implement an integrated care model to ensure optimal transition from hospital to ambulatory care 1, 2

Critical Pitfalls to Avoid

• Never delay anticoagulation while awaiting diagnostic confirmation in patients with intermediate or high clinical probability 1, 2
• Do not measure D-dimers in patients with high clinical probability, as normal results do not safely exclude PE 1, 2
• Avoid aggressive fluid resuscitation in PE patients with RV dysfunction, as this worsens hemodynamics 3
• Do not overlook right-to-left shunting through a patent foramen ovale as a cause of refractory hypoxemia 3
• Do not fail to consider rescue thrombolysis in patients with worsening hypoxemia and hemodynamic deterioration despite anticoagulation 3
• Do not routinely use IVC filters or systemic thrombolysis in intermediate/low-risk PE 1, 2