6.2 Pulmonary Embolism Flashcards
Define embolism
Movement of material rom one part of the circulation to another
Define pulmonary embolism
Thrombus entering the right side of the heart and pulmonary arteries
What things can be embolised?
Thrombus Air Fat Tumour Amniotic fluid Bullet
What happens if AF gets into lung?
Causes an inflammatory response which can lead to acute respiratory distress
What % of PE arise from DVT in legs?
90%
Which veins for DVTs usually arise from?
Popliteal vein
(And more proximal veins including pelvic veins
What are some risk factors for thromboembolism?
Age >40 years, surgery >30 mins, obesity, cancer, pregnancy, long haul travel >4hrs, prolonged immobilisation, previous thromboembolism, heart failure, contraceptive pill, HRT, thrombophilia
What three things could cause PE?
Right ventricular overload
Respiratory failure
Pulmonary infarction
What happens in right ventricular overload?
> 30% of pulmonary arterial bed occluded
Pulmonary artery pressure increases
Leads to RV dilation and stain
Inotropes released to maintain BP cause pulmonary artery vasoconstriction
Why may someone get respiratory failure?
Areas of ventilation perfusion mismatch
Low RV output
What is a feature of pleuretic pain?
Worse on inspiration
What are some symptoms of PE?
Dysopnea Pleuretic chest pain Cough Substernal chest pain - RV struggling Haemoptysis Syncope Unilateral leg pain
What are some differential diagnoses of PE?
MI
Pneumothorax
Pneumonia/pleurisy
What physical signs may be seen in PE?
Pleural rub
Raised JVP
What investigations should be done in PE?
CXR
ECG
Blood gases
D dimer
