Blood Clots

What is a blood clot?

Symptoms of a blood clot

Because blood clots can cause serious health problems, it is important to recognize the signs and symptoms of a blood clot. These signs and symptoms may vary, depending on the location of the clot in the body.

Deep vein thrombosis (DVT): If the blood clot is in a deep vein, usually in a leg or arm, signs and symptoms may include: 

• Pain or tenderness 
• Swelling 
• Warmth 
• Redness or discoloration of the skin 

Pulmonary embolism: If the blood clot travels to the lungs, signs and symptoms may include:

• Chest pain
• Shortness of breath, trouble breathing, or pain when breathing
• Rapid heartbeat or heart racing
• Unexplained cough or coughing up blood

Stroke: If the blood clot travels to the brain, signs and symptoms may include:

• One-sided numbness or weakness in the face, arms, or legs 
• Sudden, strong headache
• Confusion
• Dizziness or balance problems
• Vision changes
• Trouble speaking or understanding speech
• Face drooping, often on one side, or trouble smiling
• Drooling

When to seek emergency help

A blood clot can be a medical emergency. Call 911 or go to the emergency room right away if your child has any signs of pulmonary embolism, stroke, or sudden severe swelling or pain.

Causes of blood clots and risk factors

Certain factors can increase your child’s risk of a blood clot. These include:

• Recent surgery or injury
• Long periods of inactivity or bedrest
• Having a central venous catheter (central line)
• Certain illnesses, such as infection, chronic inflammatory diseases, cancer, sickle cell disease, or blood disorders
• Clotting disorders (thrombophilia), which increase the risk of blood clots
• Some medicines, such as certain types of hormone therapy or birth control pills
• Obesity
• Smoking
• Family history of blood clots

Diagnosis of blood clots

Blood clots are diagnosed based on your child’s medical history, physical exam, and test results. Tests may include blood tests and imaging tests. 

Blood tests may include a complete blood count (CBC) and a D-dimer test. A D-dimer test measures protein fragments that are released when blood clots break down.  

Imaging tests may include an ultrasound or CT scan to examine blood vessels and check for a blood clot. 

Treatment of blood clots

The treatment for a blood clot is based on your child’s medical history, where the clot is, and what caused it.  

Medicines called anticoagulants (blood thinners) are the main treatment for blood clots. In some cases, medicines may be used to dissolve the clot, or a procedure may be needed to remove it. 

Your child may need additional tests to monitor the blood clot. 

Post-thrombotic syndrome (PTS) 

Post-thrombotic syndrome (PTS) is a potential long-term complication following a deep vein thrombosis. PTS is caused by damage to a blood vessel after a blood clot. 

Signs and symptoms of post-thrombotic syndrome may include: 

• Pain 
• Swelling 
• Itching 
• Skin discoloration  

In the severe form, post-thrombotic syndrome can cause sores or ulcers on the skin. These can be hard to heal. 

These signs and symptoms can be similar to signs of a blood clot. Seek medical care if the symptoms persist, get worse, or if you are unsure of the cause. 

Ways to help manage post-thrombotic syndrome include: 

• Take anticoagulant medicine as prescribed to treat the clot and reduce the risk for complications. 
• Wear compression stockings if recommended. 
• Be physically active. 
• If swelling develops, elevate the affected arm or leg above the heart as recommended by your care team. 

How to prevent blood clots

Not all blood clots can be prevented. But there are steps you can take to help lower your child's risk. Ways to help prevent blood clots include: 

• Encourage your child to move around and avoid sitting or lying in one position for long periods when possible. 
• Make sure your child drinks enough fluids. Staying hydrated can help support healthy blood flow. 
• Help your child maintain a healthy weight through healthy eating and regular physical activity. 
• Do not allow smoking or vaping around your child and encourage teens not to use tobacco products. 
• Follow all instructions for medicines, including blood thinners if prescribed. 
• If your child has a central line, follow line care instructions and watch for signs of infection. 
• Keep follow-up appointments and let the care team know about any new symptoms. 

Talk to your care team about your child’s risk for blood clots and the signs and symptoms to watch for. Always follow the instructions given by your care team to prevent and manage blood clots.  

Questions to ask your care team

• What is my child’s risk of blood clots? 
• How can I reduce my child’s risk of getting a blood clot? 
• What blood clot symptoms should I watch for? 
• How are blood clots treated?  
• When should I call the care team? 
• What symptoms mean I should call 911 or go to the emergency room? 
• If my child takes a blood thinner, what bleeding symptoms should I watch for? 
• Does my child need follow-up tests or imaging? 

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