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Critical limb ischaemia

Critical limb ischaemia (isc-ee-mi-a) is a lack of blood supply to parts of your arm or leg. It develops over time, unlike acute limb ischaemia, which happens suddenly.

Critical limb ischaemia is caused by peripheral vascular disease. It means that your arm or leg doesn't get enough oxygen. When body tissues don't get enough blood supply, the tissue dies. This shows as dry, black skin and is called gangrene.

The symptoms of critical limb ischaemia include severe pain, even when at rest, and ulcers or sores.

Critical limb ischaemia doesn't get better by itself. It's a serious condition and needs to be treated by a vascular specialist (a surgical doctor who specialises in blood vessels).

How is critical limb ischaemia diagnosed?

Your doctor will examine you and ask you questions about your health, and about your family's health. They may arrange tests like an ankle-brachial index, a doppler ultrasound or an angiogram. For information about these tests, see Tests for blood vessel problems.

How is critical limb ischaemia treated?

Treatment options include reducing your risk factors, walking exercise, medication and surgery.

Reducing your risk factors

You can’t control all risk factors, but lifestyle changes can help you lower some risks. This means:

Walking exercise

Walking exercise can be as good for critical limb ischaemia as surgery. As well as helping you keep active, walking helps small new blood vessels grow that improve the blood flow in your legs.

You should walk for at least one hour, three times a week. Within the hour, you can stop and rest as often as you need to. If you get a pain in your leg while walking, stop and rest until it goes away.

If you feel embarrassed stopping and starting while walking on the street, you could try walking in a shopping mall.

Taking medication

You are likely to be prescribed a statin cholesterol medicine (even if you don't have high cholesterol) and an anti-clotting medicine like low-dose aspirin or clopidogrel to help prevent blood clots from forming.

If you have high blood pressure, or diabetes, it's very important to control these well. You'll be prescribed medication to control these conditions.


The main aim of surgery is to save your limb. If the blockage can't be treated with angioplasty, then arterial bypass surgery is needed. For more information about these types of surgery, see Treatments for blood vessel problems.

If it isn't possible to unblock the artery and increase the blood supply, the affected body part (toe, finger, foot or leg) has to be surgically removed.

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Written by HealthInfo clinical advisers. Page created July 2018.


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