What is the recommended treatment for a patient diagnosed with pulmonary embolism?

Treatment of Pulmonary Embolism

For patients diagnosed with pulmonary embolism (PE), immediate anticoagulation therapy is the cornerstone of treatment, with risk stratification determining the specific approach. 1

Risk Stratification

• PE is classified into three risk categories that guide treatment decisions 1:
  • High-risk (massive): Hemodynamic instability (hypotension, shock)
  • Intermediate-risk (submassive): Hemodynamically stable with right ventricular dysfunction or elevated cardiac biomarkers
  • Low-risk: Hemodynamically stable without right ventricular dysfunction

Initial Management

High-Risk PE

• Initiate unfractionated heparin (UFH) immediately with a weight-adjusted bolus injection 1
• Administer systemic thrombolytic therapy as the primary reperfusion strategy 1
• Consider surgical pulmonary embolectomy when thrombolysis is contraindicated or has failed 1
• Percutaneous catheter-directed treatment should be considered as an alternative when thrombolysis is contraindicated or has failed 1
• Provide hemodynamic support with norepinephrine and/or dobutamine 1, 2
• Extracorporeal membrane oxygenation (ECMO) may be considered in patients with refractory circulatory collapse or cardiac arrest 1

Intermediate-Risk or Low-Risk PE

• Begin anticoagulation immediately while diagnostic workup is in progress if clinical suspicion is high or intermediate 1, 3
• For parenteral anticoagulation, low molecular weight heparin (LMWH) or fondaparinux is preferred over UFH for most patients 1
• For patients eligible for oral anticoagulation, direct oral anticoagulants (DOACs) such as apixaban, dabigatran, edoxaban, or rivaroxaban are recommended over vitamin K antagonists (VKAs) 1, 3, 4
• If VKAs are used, overlap with parenteral anticoagulation until an INR of 2.0-3.0 is reached 1
• Rescue thrombolytic therapy is indicated for patients who develop hemodynamic deterioration while on anticoagulation 1
• Routine use of primary systemic thrombolysis is not recommended for intermediate or low-risk PE 1, 5

Special Considerations

• DOACs are contraindicated in patients with severe renal impairment, during pregnancy and lactation, and in patients with antiphospholipid antibody syndrome 1, 4
• Inferior vena cava (IVC) filters should be considered only in patients with absolute contraindications to anticoagulation or with recurrent PE despite adequate anticoagulation 1
• Routine use of IVC filters is not recommended 1
• Carefully selected low-risk PE patients may be considered for early discharge and home treatment if proper outpatient care and anticoagulation can be provided 1, 3

Oxygen Therapy and Respiratory Support

• Provide supplemental oxygen for patients with SaO₂ <90% 2
• Consider high-flow oxygen via nasal cannula if conventional oxygen supplementation is insufficient 2
• Use non-invasive ventilation before resorting to invasive mechanical ventilation 2
• If intubation becomes necessary, use low tidal volumes (6 mL/kg) and maintain plateau pressure <30 cm H₂O 2

Duration of Treatment

• Administer therapeutic anticoagulation for at least 3 months to all PE patients 3
• After 3 months, reassess the risk-benefit ratio for continued anticoagulation based on risk factors for recurrence 3

Common Pitfalls to Avoid

• Delaying anticoagulation while awaiting diagnostic confirmation in patients with high clinical probability 3, 6
• Using DOACs in patients with severe renal impairment or antiphospholipid antibody syndrome 1, 4
• Administering aggressive fluid challenges in PE patients with right ventricular dysfunction 2
• Failing to consider rescue thrombolysis in patients with worsening hypoxemia and hemodynamic deterioration despite anticoagulation 1, 2
• Losing patients to follow-up after initial treatment, risking missed diagnosis of chronic thromboembolic pulmonary hypertension 3