A pulmonary embolism occurs suddenly. It happens when any main pulmonary artery or its branches are blocked by any bodily material. Generally, this blockage occurs due to some migrated blood clots from the legs as legs are the common site where clots are formed in the body. Other reasons for this are bone marrow fat is thrown into the bloodstream when long bones are fractured, amniotic fluids, and air bubbles.
The normal signs with which a pulmonary embolism presents itself are rapid breathing, chest pain when inspiring, rapid or irregular pulse, abnormally low blood pressure, and mild fever. Other pulmonary embolism symptoms include profuse sweating, cyanosis, dizziness, and in severe cases, passing out. Unlike cardiac problems, these pulmonary embolism symptoms increase on exertion.
Diagnosis is mostly done on the basis of medical history and clinical condition. The common tests are blood for oxygen and carbon dioxide and for a substance called a D dimer which dissolves clots. Markers of genetic tendencies are also tested. A low value of D dimer helps eliminate embolism from consideration. Auscultation of the chest may give an idea of an infarct. A spiral CT scan can confirm the diagnosis. Chest X-ray helps eliminate diseases with similar symptoms. An MRI, though expensive, is generally reserved for those who cannot undergo CT scans like pregnant ladies. A duplex ultrasound scan is used to detect clots in the veins of the legs and thighs.
Treatment of pulmonary embolism is aimed at preventing further formation of clots. Anticoagulants such as heparin are given. The body normally dissolves the clots. However, in the case of larger clots, drugs called thrombolytics, capable of dissolving clots, are given as an intravenous infusion. The very big thrombi sometimes need to be removed surgically. The venous filter is sometimes used in patients who cannot take anticoagulants or they do not work fast enough. A catheter is threaded up the inferior vena cave, the vein that brings blood from the lower body and filter is placed in an appropriate place. This prevents clots from traveling to critical organs.