This page gives you information about having an operation on your leg to bypass a narrowing or blockage in a blood vessel. This information answers some of the commonly asked questions with regard to hospital admission, the operation and discharge home.

Why do I need the operation?

The arteries in your leg are the main blood supply that carries oxygen to your feet. One or more of these arteries has become narrowed or blocked due to arterial disease (atherosclerosis). Arterial disease can be caused by a number of things including smoking, high cholesterol, obesity, lack of exercise and family history. The narrowing and/or blockage of the arteries in the leg can cause pain, ulceration or gangrene. If the blood supply to your leg is not improved, there is a risk that you may need an amputation.

Benefits of the operation

  • To improve the circulation to your leg.
  • To prevent your symptoms becoming worse.
  • To improve any symptoms that you currently have such as pain or ulceration.
  • To allow the safe removal of any gangrene that may be present on your foot.

About the operation

The aim of this operation is to bypass the narrowing or blockage so the blood flow to your leg is improved. This will be done using either one of your own leg veins or an artificial graft (tube). The operation will be performed using either a general and/or epidural anaesthetic. A general anaesthetic will mean that you are asleep for the whole operation.

An epidural anaesthetic is given by an injection into your back (after numbing the skin with local anaesthetic). This will have the effect of numbing the lower part of your body during the operation. This may be used with sedation so that you are sleepy or asleep throughout the operation.

The epidural may also be used to control pain after your operation.

Your anaesthetist and surgeon will advise you of the type of anaesthetic to be used based on your general fitness and any other medical problems you may have.

Risks and complications

Surgery is performed only with your consent. If you decide against surgery the symptoms in your leg could continue to deteriorate and you may be at risk of losing your leg. There is also a risk of wide spread infection (sepsis) and failure of your major organs which is life threatening.

  • As with all major surgery there is a risk of you not surviving the operation. National figures quote a risk of up to 5 in every 100 cases of this happening - this will depend on your overall fitness and will be discussed with you before surgery.
  • Heart attack.
  • Chest, wound or graft infection.
  • Deep Vein Thrombosis (DVT), Pulmonary Embolism (PE) (clot in your leg or lung). To prevent clots forming you will be given daily injections of a medication to thin the blood.
  • The graft may become blocked. If this happens, further surgery may be necessary and includes the possibility of an amputation.
  • Areas of numbness or altered sensation around the wounds and in the area over the graft. This usually improves but can be permanent but will not affect the strength or mobility of your leg.
  • Swelling of the leg. This is usually temporary but can take several months to fully recover.

What to expect

You will be admitted to hospital, usually on the day of your operation. You can expect to be in hospital for 5 to 10 days.

Following your operation, you will be monitored in the recovery area of the operating theatre department until you are well enough to be taken to a surgical ward for the rest of your hospital stay. Sometimes it is necessary for patients to be transferred to the High Dependency Unit (HDU) overnight for further monitoring after their operation. It is important that your relatives and friends are aware that this can be part of the normal procedure.

Pain control

You will have some pain and discomfort after your operation but you will be given strong pain relief to control this.

After the operation pain relief may be given through the epidural as explained earlier on this page. You will be monitored closely to make sure that the pain control is working. Your pain relief will be gradually reduced and when the epidural is removed you will be given regular pain relief medication in tablet form or suppositories according to your needs.

Bowel movements and passing urine

A catheter tube will be passed into your bladder during the operation to drain away the urine. This will be removed when you are mobile and able to walk to the toilet.

You are unlikely to have your bowels open for the first few days after the operation. Once they begin working again you may have diarrhoea. This usually settles within 24 hours.

Some pain relief medication can cause constipation so a diet high in bran, fresh fruit and vegetables is advisable. It is also advisable to drink plenty of water each day. If constipation becomes a problem, please contact your GP as you may need a mild laxative.

Wound care

You may have a wound drain inserted while you are in the operating theatre, this is normally removed the day after your operation. Dissolvable stitches or small metal skin clips are normally used to close your wounds. If skin clips are used these will be removed 10 days after your operation by the district or practice nurse, the ward will arrange this for you.

You will be able to shower or take a bath normally before you go home.

Going home

Once you are mobile and eating and drinking normally, arrangements will be made for you to go home. It is important that you have periods of rest and gradually build up your normal activities each day.

It is advisable when you are resting that you raise your leg on a stool or settee and avoid long periods with your leg down to help reduce any swelling.

Recovery can take several months and you may feel very tired for weeks or months after your operation.

You can begin driving again once you can perform an emergency stop comfortably and without hesitation. It is advised that you inform your car insurance company that you have had an operation.

Follow up

You will be seen in the outpatient clinic about 4 to 6 weeks after your discharge.

Graft monitoring

If we have used a vein for your bypass, we will arrange for you to have regular ultrasound scans for the first year to monitor the graft. If an artificial graft has been used your surgeon may request that it is also monitored in this way.

Contact information


If you have any concerns before being seen in the follow-up clinic, please contact your GP or NHS 111 for advice.

NHS 111

Tel: 111

Vascular Ward 2A

Gloucestershire Royal Hospital

Tel: 0300 4226776

Further information

Printable version of this page

Having a leg bypass operation GHPI0337_02_23 Department: Vascular Review due: February 2026 PDF, 117.8 KB, 5 pages
Reference number GHPI0337_02_23
Department Vascular
Review due February 2026