Venous thrombosis (blood clots)

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What is this information about?

This information is about how you can reduce the chance that you may get a venous thrombosis (blood clot in the vein) while you are in hospital (a hospital associated blood clot). It explains:

• what hospital associated blood clots are 
• how likely you may be to get a blood clot while you are in hospital 
• the things that might make you more likely to get a blood clot 
• what things you and the hospital staff can do to reduce the chance that you might get a blood clot 
• how you can reduce the chance that you will get a blood clot when you go home after your stay in hospital 
• where you can find further information and support.

Why have I been given this information?

You have been given this information because you are staying in hospital. This means there is a greater chance of you getting a ‘hospital associated’ blood clot.  

Getting a blood clot can be dangerous and sometimes even life-threatening. Following the advice in this information can reduce the chance that you will get a hospital associated blood clot.

What is a hospital associated blood clot?

A blood clot is a blockage in a vein that stops your blood from flowing properly. A blood clot is also called a ‘thrombosis’.   

A blood clot is called a “hospital associated blood clot” if a person gets them while they are staying in hospital or up to three months after they have left hospital. People are more likely to get blood clots after they have had an illness or operation.   

There are two kinds of thrombosis (blood clot) that can happen in your veins:

1. Deep Vein Thrombosis (DVT):

A DVT is a blood clot that forms in a vein deep inside the body, usually in your leg or pelvis. It often starts in the calf (the back of the lower leg) but can be in the thigh. Symptoms of a DVT include:  

• swelling 
• redness 
• pain 

If you have a DVT these symptoms are most likely to be in your leg.

  2. Pulmonary Embolism (PE):

If a DVT is not treated, a part of it can break off. This is called an embolus. An embolus can travel through your veins and heart and then into your lungs. It can become stuck in the blood vessels in your lung and stop your blood from flowing properly. This is called a pulmonary embolism (PE). Symptoms of a PE include: 

• chest pain 
• breathlessness 
• coughing (some people may have blood in their phlegm (sputum) when they cough) 
• sudden collapse.

Health professionals often call both a DVT or a PE a venous thromboembolism (VTE).

How likely is it that someone will get a blood clot?

In every year, about one in 1000 people will get a blood clot. You may have heard about blood clots in people who have been on a long flight, but you are much more likely to get a blood clot after going into hospital. About two out of three blood clots happen during or after a stay in hospital. 

Hospital-acquired blood clots are an important problem. For everyone that comes into hospital a doctor, nurse or pharmacist will check the chance that you may get a blood clot.  

If we think that there is a chance that you may get a blood clot, we will do everything that we can to make sure you do not get one. We will talk with you about what will be done to reduce the chances of you getting a blood clot.

What things (risk factors) might make me more likely to get a blood clot?

Any unwell adult who has to stay in hospital has a greater chance of getting a blood clot. That is most patients who come into hospital. 

Other things which may mean that you are more likely to get a blood clot include:

• having had a blood clot before 
• having a recent diagnosis of cancer 
• having a current Covid-19 infection 
• some ‘sticky blood’ conditions. These include antiphospholipid syndrome or Factor V Leiden 
• having a first degree relative (your parents, siblings or children) who has had a thrombosis 
• being overweight 
• being immobile (not getting much exercise or not moving around much) 
• taking contraceptives that have oestrogen in them or hormone replacement tablets 
• having an operation 
• having a serious injury or a traumatic injury (an injury caused by violence or an accident)  
• being pregnant or having recently been pregnant, including having a miscarriage.

What might hospital staff do to reduce the chance that I might get a blood clot?

Hospital staff may give you:

• Stockings

In hospital, you might be measured and fitted with anti-embolism (anti blood clot) stockings for your legs. You should be shown how to wear them and told to report any new pain or discomfort in your feet or legs to a health professional.  

Your stockings will be removed for a short time every day so that you can have a wash and check for any skin problems.  Sometimes we use inflatable sleeves to increase your blood flow.

• Blood thinners:

Most people who have an increased chance of getting a blood clot will be prescribed a small dose of an anticoagulant (blood thinner). These reduce the chance of you having a blood clot thrombosis by thinning your blood slightly.

If you need to take these medicines when you leave hospital, you will be told how long to take them for. The blood thinner used most often is a heparin injection. 

Both stockings and blood thinning medicines must be used in the right way so that they can work as well as possible to help to stop you getting a blood clot.

Do

• Ask your doctor or nurse if you have any questions or concerns about using stockings or blood thinners. 
• Tell the doctor if you have ever been diagnosed as having a bleeding disorder such as haemophilia or Von Willebrand’s disease. If you have had a bleeding disorder, we will not usually give you anticoagulant medicines as it is not safe.

What can I do myself to reduce the chance that I will get a blood clot?

• Before you come into hospital:
  • keep to a healthy weight 
  • do regular exercise 
  • avoid smoking 
  • talk to your pre-op or surgical team about contraceptives or hormone replacement therapy if you are using either of these.  Your doctor may ask you to stop using these in the weeks before your operation. They will advise you about other contraceptives that you may be able to use if you have to stop your usual method for a while.
• When you are in hospital:
  • Keep moving or walking and get out of bed as soon as you are allowed after an operation. Ask your nurse or physiotherapist for more information. 
  • Ask your doctor or nurse: “What is being done to reduce my risk of getting a blood clot?” 
  • Drink plenty of fluids such as water, tea, or squash to keep hydrated.  
  • Wear your anti-embolism stockings and make sure they fit without causing pain.

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 how to check your skin for damage.   

If you need to continue anticoagulation injections or tablets 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.

What are the most important things that I should remember to do to reduce my chances of getting a blood clot?

What must I do if I get any signs or symptoms of a blood clot?

Do seek medical advice straight away.

• If you are in hospital, tell a doctor, nurse or other health professional. 
• If you are not in hospital call NHS 111 or your GP surgery or visit your nearest A&E (Emergency Department).

Where can I find further information?

• NHS website

• Thrombosis UK website

Who can I contact if I have further questions or concerns after I have read this information?

Contact Louise Burgess, VTE Improvement Nurse: 

Phone: 01903 205 111 ext. 86267 or 01243 788 122 ext. 35254 from 8am to 4pm.