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FAQ: What You Should Know About Blood Clots

October 12, 2022

Thrombosis is a pathological blood clot in a blood vessel that once formed slows or blocks normal blood flow throughout the body. It can affect anyone, anytime, anywhere –but can be preventable! It’s important to know your risk level and familiarize yourself with the signs and symptoms including swelling and pain, chest pain, discoloration and warmth at clot site, numbness on one side of the body, sudden shortness of breath, coughing up blood and a rapid or irregular heart rate. Our team from the Thrombosis Program, part of the Center for Cancer and Blood Disorders at Lurie Children’s, answer questions about blood clots below.

What is a blood clot?

When a blood clot forms abnormally within a vessel, or in a place where it is not needed, it is called a thrombus. Blood clots that form in veins are different from clots that occur in arteries.

  • Clots in Arteries: Blood clots that form in arteries lead to stroke, transient ischemic attack (TIA, also known as a mini-stroke) or heart attack.
  • Clots in Veins: When a clot, or thrombus, forms in the large veins (usually in the arms or legs) it is a condition called deep venous thrombosis (DVT). If left untreated, these clots can grow, break and/or travel in the blood stream. A clot traveling in the blood stream is called an embolus. When an embolus gets stuck in the arteries of the lungs, it is a condition called a pulmonary embolism (PE). Sometimes, a PE can form in the lung without signs of a DVT.

What causes a blood clot to form where it isn’t needed?

A blood clot may form when blood flow slows down too much, or if there is damage to the vein. A person’s blood may also be more likely to form clots because of an inherited or acquired condition.

What are the risk factors for developing a blood clot in children or adolescents?

  • Hospitalization – bed rest, little motion for extended periods
  • Catheter in a big vein (a catheter is a piece of plastic tubing put into a vein or artery)
  • Medical conditions – cancer, lupus and others
  • Surgery or injury
  • Previous history of a blood clot or a family history of blood clots
  • Clotting disorder (inherited or acquired)
  • Obesity
  • Birth control pills (containing estrogen)
  • Pregnancy
  • Cigarette smoking
  • Travel — long plane/car trips without movement
  • Dehydration

What is the treatment?

To treat blood clots (a thrombus or an embolus) doctors prescribe blood thinners, called anticoagulants. The goals of this treatment are to prevent new clots from forming, prevent the growth of the existing clot and allow the body to dissolve the clot and heal.

Do people recover completely?

Most people recover completely from a blood clotting event. However, in some patients the clot may go away only partially, or not go away at all. Some people don’t recover completely because the clot damaged the valves within the vein. This can lead to a variety of symptoms called post thrombotic syndrome (PTS). Symptoms of PTS include continued pain, aching or cramping, swelling, discolored skin, eczema and skin ulcers. Doctors may prescribe compression stockings to help prevent PTS.

What are the symptoms of a blood clot?

The typical symptoms of DVT and PE are explained below. Symptoms of a blood clot can range from mild to severe, and in a few instances there may be no symptoms at all.

Pulmonary embolism (PE) A clot traveling in the blood stream is called an embolus. When an embolus gets stuck in the arteries of the lungs, it is a condition called a pulmonary embolism (PE).

PE symptoms include shortness of breath, chest pain (which may be worse with deep breath), an unexplained cough, rapid heart beat.

Deep vein thrombosis (DVT) When a clot, or thrombus, forms in the large veins (usually in the arms or legs) it is a condition called deep venous thrombosis (DVT).

DVT symptoms include pain, swelling, discoloration (bluish, purplish or reddish skin).

Tips to help prevent DVT/PE

  • Move around as soon as possible after having been confined to bed, such as after surgery, illness or injury.
  • When sitting for long periods of time — such as when traveling for more than four hours — get up and walk around every two to three hours. If you cannot get up to walk, stretch your lower legs.
  • Drink plenty of water to stay hydrated, and avoid drinking anything with alcohol or caffeine in it.
  • Exercise regularly, maintain a healthy weight and don’t smoke.
  • If you or your child have risk factors for blood clots, talk to your doctor about graduated compression stockings or medication (blood thinners) to prevent or treat DVT.
  • Blood clots can be hard to diagnose in youth and infants, as it can mimic other conditions. If you have a family history of blood clots, please talk to your doctors.

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