Preventing hospital-associated blood clots

This leaflet explains about blood clots which can happen during or after illness, hospital admission and surgery.

What are hospital-associated blood clots?

A hospital-associated blood clot happens in patients when they are in hospital, and can happen up to 90 days after they leave hospital. There are two kinds.

1. Deep-vein thrombosis (DVT): a DVT is a blood clot (also known as thrombosis) that forms in a deep vein, most commonly in your leg or pelvis. It may cause no symptoms at all or cause swelling or discoloration of the leg – red, purple or blue changes – and pain.
2. Pulmonary embolism (PE): if all or part of the clot breaks free and passes through your blood vessels, it can reach your lungs. This is called a PE. Symptoms include coughing (with blood stained phlegm), chest pain and breathlessness or collapse.
3. Health professionals use the term venous thromboembolism (VTE), to cover both DVT and PE.

If you develop any of these symptoms either in hospital or after you go home, please get medical advice immediately.

Are blood clots common?

Blood clots happen in the general population in about 1000 people every year. You may have heard about people getting a DVT after flying, but you are much more likely to get a blood clot after going into hospital. In fact, about two-thirds of all blood clots happen during or in the 90 days after a stay in hospital.

Although these risks are still small, the consequences can be serious. Blood clots can lead to long-term medical problems such as permanent swelling in the leg, varicose veins and even leg ulcers. They can even lead to death.

The government knows that hospital-associated blood clots are an important problem and have asked hospital doctors, nurses, midwives and pharmacists to assess the risk to patients. If you are at risk, your doctor or nurse will talk with you about what will be done to protect you against clots.

Who is at risk?

Any adult who is unwell and is admitted to hospital is at risk.

Other factors that put people at greater risk include the following:

• a previous clot
• a recent diagnosis of cancer
• being overweight (body mass index of more than 30)
• not being able to move about
• taking oestrogen-containing contraceptives and hormone replacement
• having an operation
• being older than 60
• suffering significant injury or trauma
• being pregnant and after giving birth
• dehydration
• smoking
• varicose veins
• certain ‘sticky blood’ conditions such as antiphospholipid syndrome or Factor V Leiden

What can I do to reduce my risk?

Stockings: If you are admitted to hospital, you might be measured and fitted with anti-embolism stockings for your legs. You should be shown how to wear them and told to tell a health professional about any new pain or discomfort in your feet or legs. Your stockings will be removed for a short time twice a day so that you can have a wash and check for any skin problems.

Inflatable sleeves: The clinical team may ask you to wear leg or foot pumps. These are special inflatable sleeves which you will wear around your legs or feet while you are in bed or sitting in a chair. These will inflate automatically and provide pressure at regular intervals, increasing blood flow out of your legs.

Blood thinners: Most patients at risk will be prescribed a small dose of an anticoagulant. This reduces the chance of having a blood clot by thinning your blood slightly. If you need to take a blood thinner when you leave hospital, you will be told how long to take it for. The blood thinner most often used is a type of heparin, which is given by injection. Heparin comes from animals. If you have any concerns about using animal products, please tell your doctor and they will discuss other options with you. Blood-thinning tablets are increasingly being used after orthopaedic surgery.

To be effective, you must use these methods of prevention correctly. If you have any questions or concerns, please ask your doctor or nurse.

What can I do to help myself?

If possible, before you come into hospital:

• talk to your doctor about contraceptives or hormone-replacement therapy (your doctor may consider stopping these in the weeks before an operation and will provide advice on temporarily using other methods if you stop taking your usual contraceptive)
• keep a healthy weight
• do regular exercise

When in hospital:

• keep moving or walking and get out of bed as soon as you can after your operation – ask your nurse: ‘What is being done to reduce my risk of clots?’
• drink plenty of fluid to keep hydrated

What happens when I go home?

Until you return to your usual level of activity, you may need to wear anti-embolism stockings after you go home. Your nurse will tell you how to put them on and what you should check your skin for. If you need to continue anticoagulation injections at home, your nursing team will teach you how to do this. If you have any concerns, make sure you speak to a nurse before you leave.

If you develop any sign or symptoms of a clot when you are at home, immediately contact your GP or your nearest hospital’s emergency department.

Contacts/ further information

Anticoagulant Team - call 01223 349831

Further information

Please follow the link below for a short video that explains why your risk of a blood clot might increase when you are in hospital, and after you go home, as well as how you and the hospital team can help reduce this risk.