Treatment of Pulmonary Embolism
For patients diagnosed with pulmonary embolism, anticoagulation should be initiated without delay, with NOACs (apixaban, dabigatran, edoxaban, or rivaroxaban) recommended over vitamin K antagonists for most patients, while high-risk PE patients with hemodynamic instability should receive systemic thrombolytic therapy. 1
Risk Stratification
Risk stratification is essential for determining appropriate treatment:
- High-risk PE: Characterized by hemodynamic instability (systolic hypotension or cardiogenic shock) 2
- Intermediate-risk PE: Right ventricular dysfunction and/or myocardial injury without hemodynamic instability 2
- Low-risk PE: Hemodynamically stable without evidence of right ventricular dysfunction or myocardial injury 2
Treatment Algorithm Based on Risk Stratification
High-Risk PE (with hemodynamic instability)
- Initiate unfractionated heparin (UFH) immediately, including a weight-adjusted bolus injection 1, 2
- Administer systemic thrombolytic therapy unless contraindicated 1, 2
- For patients with contraindications to thrombolysis or in whom thrombolysis has failed:
- Consider norepinephrine and/or dobutamine for hemodynamic support 1, 3
- Extracorporeal membrane oxygenation (ECMO) may be considered in cases of refractory circulatory collapse or cardiac arrest 1
Intermediate or Low-Risk PE
- Initiate anticoagulation without delay while diagnostic workup is in progress 1
- For parenteral anticoagulation, low molecular weight heparin (LMWH) or fondaparinux is recommended over UFH 1
- For oral anticoagulation, a non-vitamin K antagonist oral anticoagulant (NOAC) such as apixaban, dabigatran, edoxaban, or rivaroxaban is preferred over vitamin K antagonists (VKAs) 1, 4
- If VKAs are used, overlap with parenteral anticoagulation until an INR of 2.5 (range 2.0-3.0) is reached 1
- Rescue thrombolytic therapy is recommended only if hemodynamic deterioration occurs during anticoagulation treatment 1
- Routine use of primary systemic thrombolysis is not recommended in intermediate or low-risk PE 1, 2
Specific Anticoagulation Considerations
- Rivaroxaban for PE treatment: 15 mg twice daily with food for the first 21 days, followed by 20 mg once daily with food 4
- NOACs are contraindicated in patients with severe renal impairment, during pregnancy and lactation, and in patients with antiphospholipid antibody syndrome 1
- Duration of anticoagulation typically ranges from 3-6 months for provoked PE (with temporary risk factors) to indefinite treatment for unprovoked PE 5, 6
Inferior Vena Cava (IVC) Filters
- IVC filters should be considered in patients with:
- Routine use of IVC filters is not recommended 1
Respiratory Support
- Administer supplemental oxygen to patients with SaO2 <90% 3
- For patients not responding to conventional oxygen supplementation, consider high-flow oxygen via nasal cannula 3
- Non-invasive ventilation should be considered if high-flow oxygen is insufficient 3
- Invasive mechanical ventilation should be reserved for cases of extreme instability 3, 7
Early Discharge Considerations
- Carefully selected patients with low-risk PE should be considered for early discharge and continuation of treatment at home, if proper outpatient care and anticoagulant treatment can be provided 1
Common Pitfalls to Avoid
- Delaying anticoagulation while awaiting confirmatory testing in patients with high clinical suspicion 3
- Using aggressive fluid challenges in PE patients with right ventricular dysfunction, which can worsen hemodynamics 3, 7
- Failing to consider rescue thrombolysis in patients with worsening hypoxemia and hemodynamic deterioration despite anticoagulation 3
- Premature discontinuation of anticoagulation, which increases the risk of recurrent thrombotic events 4, 6