What are pulmonary emboli?
- These are clots which have formed in the deep veins, have broken off and been carried through the right side of the heart to the lungs.
- PE may cause the patients to:
– complain of central chest pain or pleuritic pain associated with deep breaths
– become breathless, coughing, to be agitated and distressed - On examination they may be cyanosed with low oxygen saturation, have an increased respiratory rate, raised heart rate (tachycardic), low blood pressure (hypotensive)
- An ECG and chest X-Ray may be abnormal but the diagnosis is best confirmed with a CT pulmonary angiogram or Ventilation/Perfusion isotope (V/Q) scan
- Like DVT, patients may have pulmonary emboli without symptoms and many others with less dramatic symptoms may be misdiagnosed as having a chest infection, pneumonia or heart failure
- Pulmonary emboli may cause the patient to collapse and die suddenly
- A pulmonary embolus should be suspected in any stroke patient who becomes breathless or hypoxic
Pulmonary emboli and the factors of Virchow’s Triad
Pulmonary embolism – blocking pulmonary arteries, lung damage.
Pyramid diagram depicts relationship between three elements of thrombosis: stagnant blood flow, injury to the blood vessel, and sticky blood.
- Low flow or stagnation of the blood which occurs in immobile patients, or those with weakness of the leg muscles.
- Injury to the veins due for example to surgery.
- Thick or sticky blood (hyercoagulable) which may occur in dehydration, with infection or malignancy.
Page last reviewed: 21 Apr 2020
