Pulmonary embolism

March 2017


Definition


A pulmonary embolism is caused by the blockage of a pulmonary artery by a blood clot. The clot fixes itself in 9 of 10 cases in the wall of a deep vein of the abdomen, pelvis or lower limb, before migrating into the bloodstream and stopping in a pulmonary artery. Pulmonary embolism is the cause of many deaths. Its appearance can be induced by:
  • blood clotting disorders;
  • a long trip spent sitting (on a plane, in a car?);
  • an orthopedic surgery
  • prolonged immobilization;
  • pregnancy or childbirth;
  • an increase in the total volume of red blood cells (polycythemia);
  • cancer;
  • cardiac or respiratory failure.

Symptoms


Circulatory failure and respiratory failure are the possible consequences of a pulmonary embolism. According to its severity, it may also have the following symptoms:
  • anxiety;
  • tachycardia;
  • a slight fever;
  • a stabbing or a "stitch" chest pain;
  • difficulty breathing, which may be accompanied by bloody sputum;
  • and sometimes cardiac arrest.

Signs of venous thrombosis of the leg are sometimes associated and strengthen the suspected diagnosis: a swollen and painful limb that is hot to the touch in comparison to the other leg. These signs are often noticed best on the calf.

Diagnosis


The diagnosis is based on signs described by the patient. A clinical examination is generally little helpful, but one may notice:
  • a rapid pulse;
  • a weak pulse;
  • the absence of abnormality in auscultation of the lungs;
  • signs of deep vein thrombosis.

To confirm the diagnosis, a chest X-ray and an electrocardiogram may be initially prescribed. A blood test with a D-dimer measuring will eliminate the diagnosis of pulmonary embolism when the results come back normal. Often, a Doppler ultrasound of the lower limbs is performed to look for venous thrombosis. If there are any worrying signs, a lung scan or an angiography scan (scan with opacification of vessels) will confirm the diagnosis.

Treatment


Hospitalization is essential in the case of a pulmonary embolism. It will allow for an ongoing assessment and optimal treatment to avoid any further complications. The patient is given oxygen and is administered anticoagulants to prevent the emergence of new clots or the spread of clots already present. In the most severe cases, surgery may be performed. After recovery, the patient will need to take blood thinners for several months or even for life.

Prevention


Prevention can be assured through:
  • walking and moving legs during prolonged periods of inactivity (air travel ...);
  • an early rehabilitation after a risky surgery;
  • wearing stockings to promote circulation to the lower limbs and to prevent the occurrence of thrombosis;
  • the administration, if at risk, of preventive doses of anticoagulants;
  • management of all cardiovascular risk factors: smoking, high cholesterol, obesity, diabetes or hypertension.

Related

Original article published by . Translated by Jeff.
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