Pulmonary Embolism

• What is a pulmonary embolism (PE)?


  A blood clot in the pulmonary arterial vasculature
• How does a pulmonary embolism typically occur?


  It typically occurs when part of a lower limb deep vein thrombosis (DVT) breaks off and travels to the lungs
• What are key symptoms of a pulmonary embolism?


  Sudden-onset shortness of breath, pleuritic chest pain, and haemoptysis
• What signs may indicate a deep vein thrombosis (DVT) in a patient with PE?


  Unilateral leg swelling
• What investigations are important if a PE is suspected?


  ECG, chest X-ray, CT pulmonary angiogram (CTPA), and echocardiogram
• What is the purpose of a D-dimer blood test in suspected PE cases?


  To risk stratify and help rule out PE
• What is the emergency management for a massive PE?

  Resuscitation and thrombolysis
• What does the PE Severity Index (PESI) score assess?


  Severity of PE based on 11 factors
• What are the estimated 30-day mortality rates for different PESI risk categories?


  0.7% in very low risk to 25% in very high risk patients
• What indicates a high-risk patient in the context of PE?

  Haemodynamic instability and elevated troponin levels
• What is the typical triad of symptoms for PE?


  Sudden-onset shortness of breath, pleuritic chest pain, and haemoptysis
• What does the presence of cough without haemoptysis indicate?


  Cough may also be present without haemoptysis
• What symptoms indicate a massive PE?


  Syncope or pre-syncope
• What examination findings may indicate massive PE?

  Hypotension, cyanosis, and signs of right heart strain
• What might a small PE result in during examination?


  A normal examination
• What is the Wells score used for?


  To risk stratify patients with a suspected PE
• How many points are given for clinical signs and symptoms of a DVT in the Wells score?


  3 points
• What does a Wells score of 4 or less indicate?


  PE unlikely, do a D-dimer
• What should be done if a D-dimer is raised?


  Further investigate with a CTPA
• What might an ECG show in a massive PE?


  Evidence of right-heart strain
• What is the classic S1Q3T3 pattern?


  Deep S waves in lead I, pathological Q waves in lead III, and inverted T waves in lead III
• What does a D-dimer test indicate?


  It is not a specific test but has a 95% negative predictive value
• What might a full blood count (FBC) show in underlying malignancy?


  It may show anaemia or thrombocytosis
• What imaging test is the diagnostic test of choice for a PE?


  CT pulmonary angiogram (CTPA)
• What might a chest X-ray show in a PE?

  Fleischner sign, Hampton's hump, or Westermark sign
• What is the role of a V/Q scan?


  Preferred in severe renal impairment or contrast allergy
• What is the conservative management for hypoxic patients?

  Oxygen therapy
• What should be done for low-risk patients with PE?


  They may be suitable for discharge with anticoagulation and outpatient follow-up
• What is the duration of anticoagulation treatment for a provoked PE?


  3 months (3-6 months if active cancer)
• What is the treatment for massive PE?


  Thrombolysis with an IV bolus of Alteplase
• What is the risk associated with thrombolysis in massive PE?


  There is a risk of haemorrhage
• What is embolectomy used for?


  In patients with a massive PE when thrombolysis is contraindicated
• What is catheter-directed thrombolysis used for?

  In specialist centres for patients with a high bleeding risk
• Why is the presence of right ventricular strain significant in PE patients?


  It is an important marker for high-risk patients
• What should be done for patients with a Wells score greater than 4?


  They are likely to have a PE and should be further investigated
• What are the two main approaches to managing PE?


  Conservative and medical approaches