Pulmonary embolism is a condition, in which a thrombus, air bubble, fat from a fractured bone or particles of other materials (such as lipid substances from an atherosclerotic plaque) reach by the way of blood circulation any pulmonary blood vessel and occlude it.
As a result, respiration turns less efficient. Air can enter the lungs freely, but oxygenation (enrichment of blood with oxygen) is impaired because of compromised blood flow.
This is an emergency situation requiring immediate diagnosis and treatment.
Symptoms may include: sudden shortness of breath, chest pain, rapid pulse rate, low blood pressure, cough (sometimes bloody cough) and more.
In some instances, pulmonary embolism can have no symptoms or only unspecific manifestations, which makes the proper diagnosis difficult.
The majority of pulmonary emboli stem from deep veins of the lower extremities.
Factors increasing the risk of deep vein thrombosis are: prolonged immobility (as, for example, during long distance flights), recent surgical procedures, malignant diseases, trauma of lower extremities, previous history of thrombosis in the lower extremities and congenital or acquired hypercoagulability states.