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Preventing blood clots when people are in hospital

A blood clot, also called a venous thromboembolism, can be a serious condition. If it forms inside a vein (often in the leg) it’s called a deep vein thrombosis, or DVT. If a piece of the blood clot travels to the lungs it can cause a blockage called a pulmonary embolism, or PE. Together these 2 conditions cause thousands of deaths each year. People in hospital have a higher chance of blood clots because when someone is unwell or not moving around their blood may not be flowing well. Blood clots can be prevented in hospital as long as some simple steps are always followed.

We want this guideline to protect people in hospital from blood clots by making sure:  

  • everyone has their risk of blood clots checked when they are admitted to hospital (including mental health units), whatever type of treatment they are having
  • each person’s risk check is used to decide whether they need treatment to prevent clots, for example blood-thinning medicines, compression stockings or foot pumps
  • if people need blood-thinning medicines to stop clots, they have their risk of bleeding checked first
  • staff explain how important it is for people to stick to their treatments after leaving hospital because a blood clot can develop weeks later.

Making decisions together

Decisions about treatment and care are best when they are made together. Your healthcare professional should give you clear information, talk with you about your options and listen carefully to your views and concerns.

They should make sure you understand how to:

  • help protect yourself against blood clots while you are in hospital – for example by staying active and walking around if you can, or flexing the muscles in your legs if you are bed bound
  • look out for possible signs of a blood clot after you leave hospital – for example, a blood clot in the lungs can cause difficulty breathing or pain in the chest
  • continue any treatments you have been given, like how to wear the compression stockings correctly, take your medicines or where to go for your injections.

Ask your healthcare professional for more advice about how to lower your risk of blood clots during and after your hospital stay.

Read more about making decisions about your care.

Where can I find out more?

The NHS website has more information about blood clots.

Find your nearest local Healthwatch.

The organisations below can give you more advice and support.

NICE is not responsible for the content of these websites.

We wrote this guideline with people who have been affected by blood clots and staff who treat and support them. All the decisions are based on the best research available.

ISBN: 978-1-4731-2872-9

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