(Acute & Emergency) (Haematology) (Clinical Imaging) (Respiratory)

Overview

• Life-threatening condition caused by a thrombi which embolizes to the lungs via the inferior vena cava, and occludes the pulmonary vasculature
• Risk Factors → Increasing Age, DVT, Recent Surgery, Bed Rest >5 days, Previous VTE or FH of VTE, Active Malignancy, Recent Trauma, Pregnancy, COCP
• Virchow's Triad can lead to DVT & PE → Vessel wall damage, Venous Stasis, Hypercoagulability

Making Diagnosis

Clinical Features:

• Dyspnoea (SOB)
• Sudden pleuritic chest pain (acute pain aggravated by coughing, swallowing or deep inspiration) → normally localised to one side of the chest
• Tachycardia and Tachypnoea → especially in absence of any respiratory signs
  • Tachypnoea = most common clinical sign
• Signs of DVT → unilateral painful leg swelling
• Cough, Fever, Haemoptysis

Investigations:

• CT Pulmonary Angiography (CTPA) → wells score >4. preferred investigation for definitive confirmation, can see thrombus in pulmonary artery
  • CT Chest showing PE
  • V/Q scan is preferred if the patient has renal impairment, contrast allergy or is pregnant. Identifies areas of ventilation and perfusion mismatch, indicating area of infarcted lung.
• D-Dimer → wells score ≤4. for non-pregnant patients. Elevated. Consider if probability of PE is low. ****
  • If raised → do CTPA
  • If negative → consider alternative diagnosis