When clots from deep venous system break off and travel to the lungs, Pulmonary Embolism (PE) occurs.
Most emboli arise from Ileo-femoral thrombosis, may also come from pelvic and upper extremity veins.
- Lower extremity venous disease
- Congestive Heart Failure (CHF)
- Recent surgery
- Family history
- Previous Deep Venous Thrombosis (DVT)
- Oral Contraceptive Pills (OCP) use
- Hypercoagulable state (factor V Leiden, antiphospholipid antibody, protein C and S deficiency)
- Fat embolus
- Air embolus
- Amniotic fluid embolism
- > 50% of PE are undiagnosed
- 90% of PE arises from a lower extremity DVT
- 50% of patients presenting with DVT have concomitant PE
Virchow’s triad indicates increased the risk of thrombus formation, endothelial trauma, stasis, and hypercoagulability.
Signs and Symptoms:
- Pleuritic chest pain
- A cough
- Haemoptysis due to pulmonary infarction
- Calf tenderness
- Homan’s sign (pain with plantar flexion)
- Signs of acute right heart dysfunction
- Pulmonary Angiogram
- Ventilation-Perfusion Ratio (V/Q) scan
- Helical (Spiral) CT
- Lower Extremity Venous Duplex Scanning
- Arterial Blood Gas (ABG)
- Chest X-Ray
- ECG: normal or tachycardia, may see S1Q3T3 or RV strain.
- Oxygen therapy.
- Anti-coagulation: IV Heparin or LMWH (less bleeding, improved mortality) when PE is clinically suspected; coumadin therapy should follow for at least 6 months and may need to be continued indefinitely depending on the underlying cause.
- IVC filter: consider if anticoagulants are contraindicated, recurrent embolism despite anticoagulation, massive PE, or poor baseline cardiac or pulmonary status.
- Systemic Thrombolytic Therapy: consider in massive PE with Hypotension or refractory hypoxemia
- Pulmonary Embolectomy: occasionally used in refractory hypotension and proven pulmonary emboli.
- IV Fluids, Norepinephrine, consider thrombolysis or surgery.