Pulmonary embolism Flashcards
What is a pulmonary embolism?
Occlusion of pulmonary arteries, mostly due to
- Blood EMbolus (DVT)
- Might be due to other causes
What is the epidemiology of a PE?
What are most pulmonary emoli caused by?
Blood clot
- 95% venous embolus, mostly derived from
- Deep Vein Thrombosis,
- possibly right atrium in patient with AF
Other that a blood emboli, what are other causes for a pulmonary embolism?
- Might be due to other embolus (e.g. fat, air, amniotic fluid, tumor, mycotic etc,)
- Fat embolus mainly due to larger surgical procedures
What are the risk factors for the development of a pulmonary embolism?
- Risk factors for development of DVT
- Endothelial damage
- Stasis
- Hypercoagulability
- Arrythmias
- Immobility and surgical patients
- Oral contraceptive Pill
- Heart Failure
- Malignancy
- Obesity
What are symptoms of a small PE?
What are sympotms of a Moderate PE?
Sudden onset
- dyspnoea
- Pleuritic chest pain
- cough
- haemoptysis
What are possible sympotms for a big PE?
Sudden onset
- dyspnoea
- pleuritic chest pain
- cough
- haemoptosis
- +
- shock
- collapse
- acute Right Heart failure and sudden death
Whar are clinical findings in a patient with a medium sized pulmonary embolus?
- Tachycardia
- Tachypnoea
- low Sats (despite O2 therapy)
- Pleural rub
What is a plueural rub sound?
What does it indicate?
Pleural rub=
- sound created by pleural linings rubbing together
- sounds like walking on fresh snow
- Sing of pleural inflammation
- due to loss of pleural fluid
Commonly found in
- Pneumonia
- PE
What are the pathophysiological problems that arise from a pulmonary embolism?
- Infarction and inflammation of pleura
- Cardiac compromise
- Impaired gas exchange
- Hyperventilation
What does infarction and inflammation of the pleural lead to in a PE?
- Leading pleuritic pain and haemoptysis
- Surfactant disfuction
Explain the effects of a PE on the cardiovascular system
- Infarction –> Ventilation/perfusion mismatch and pulmonary artery hypoxia –> constriction of pulmonary arteries –> acute pulmonary hypertension –> Forward right heart failure with decreased CO –>
What does an ABG look like in a patient with PE?
- Classig findings:
- hypoxaemia
- Hypocapnia (hyperventilation)
But might be different
- (e.g. showing mixed acidosis due to
Which investigations would you do in a patient with suspected PE?
- Wells score/Geneva Score
- ABG
- hypoxaemia
- Hypocapnia
- CT pulmonary angio (gold standart for diagnosis)
- CXR to exclude other causes
- Depending on likelyhood of differentials
- D-dimer
- Thrombophilia screen
- Doppler of lower limb: to determine/ find Venous embolism
- ECG
What is the Wells score?
Score to assess likelyhood of a person having a PE
What are findings of a PE on a CXR?
Most commonly: Unspecific signs
- pleural effusion
- cardiomegaly
- atelectasis
More specific findings are rare but include
- Hampton hump (shallow wedge-shaped opacity in lung periphery)
- and Westermark sign (sharp pulmonary vessel with distal hypoperfusion).
What is atelectasis?
Radiological sign, showing collapse or incomplete expansion of pulmonary parenchyma.
