Pulmonary embolism

Pulmonary embolism refers to a blockage in one or more of the pulmonary arteries in the lungs. 

A doctor showing an x-ray to a patient

In most cases its causes include blood clots that originate in the deep veins in the legs (deep vein thrombosis or DVT), which travel from the legs (or from other parts of the body, that is, arms or pelvis, but the latter is rare) to the lungs. 

In some cases, material other than a blood clot can cause the blockage in the pulmonary artery, including air bubbles, a section of a tumour, or fatty tissue from the marrow of a broken long bone. 

What are its symptoms?

Pulmonary embolism symptoms include the following:

  • Chest pain that worsens when you breathe deeply (with associated infarction, or tissue death caused by lack of oxygen, of the lung), and also angina-like chest pain (heavy, crushing pain in the centre of the chest)
  • Shortness of breath that worsens with exertion
  • Cough with blood or blood-streaked phlegm
  • Leg pain and/or swelling
  • Cyanosis (bluish discolouration of the skin and mucous membranes)
  • Fever
  • Profuse sweating
  • Dizziness

A pulmonary embolism can be life threatening, so seek medical attention immediately should you have any of these symptoms.

How is it diagnosed? 

A pulmonary embolism diagnosis will involve a thorough physical exam, and a comprehensive discussion of your medical history and risk factors. This will help determine which tests your doctor would choose to perform. These tests may include:

  • A blood test: This can establish the presence of a clot-dissolving substance known as D-dimer, high levels of which may indicate an increased likelihood of blood clots.
  • Ultrasound: A scan using high-frequency sounds waves is used to check for blood clots in the thigh veins.
  • CT (computerised tomography) scan: 3D images of the lungs are created using a spiral CT scan that can detect abnormalities with greater precision.
  • A pulmonary angiogram: This is the most accurate way to diagnose pulmonary embolism as it provides a clear picture of the blood flow in the arteries in the lungs. It is only performed if other tests are inconclusive – as there are potentially serious risks involved with the procedure. 

What are your treatment options? 

Pulmonary embolism treatment aims to prevent the blood clot from getting any bigger, dissolving the clot and new clots from forming. 

Treatment options include:

  • Anticoagulation medication or blood thinners may be administered – this prevents new clots from forming. Heparin is a well-known anticoagulant that can be injected into a vein or under the skin. It may be overlapped with warfarin, which is an oral blood thinner. 
  • Surgical treatment involves removing life-threatening blood clots using a catheter that is threaded through the blood vessels.
  • For those patients who are unable to take anticoagulants or they don’t work quickly enough, a vein filter may be place in the body’s main vein (the inferior vena cava) that goes from the legs to the right side of your heart. 

Can it be prevented? 

Anyone may develop blood clots, but there are certain factors that increase the risk:

  • A family history
  • Heart disease
  • Certain cancers may increase substances in the body that promote blot clotting
  • Being immobile, for example, being confined to bed after surgery, or sitting in a cramped position for lengthy trips
  • Surgery: Being immobile during surgery or tissue debris that enters the bloodstream increase the risk of blood clots forming. Anyone undergoing a surgery that may result in DVT is usually given medication to prevent clot formation before and after surgery.
  • Other risk factors include smoking, being overweight, pregnancy and supplemental oestrogen in birth control pills and hormone replacement therapy (HRT)

For more info

The Heart and Stroke Foundation South Africa

IMAGE CREDIT: 123rf.com

The accuracy of this information was checked and approved by physician Dr Thomas Blake in June 2016