What is critical limb ischaemia and how will I know I have it?

Critical limb ischemia is the last stage of peripheral arterial disease. The peripheral arterial disease is divided in two groups, whatever is non-CLI, whatever is CLI. So, what is CLI? CLI is, as I said, the last stage which includes different scenarios, could be what is called Rutherford's 4 stage which means the patient when goes to bed when lies down flat has pain at the level of the calf or even at the level of the foot. That means then by gravity when the patient stays in bed or lies down the heart can't pump enough of course by the gravity to reach a satisfactory blood flow supply to the foot. That means that the blood is very very slow going through collaterals and the patient feels pain. It's the same pain of a heart attack more or less so the muscle which requires blood doesn't receive enough and of course it's not the same as a heart attack because the muscle in the leg can resist for hours, days, even months without an appropriate blood supply but still the pain is very much the same stabbing and cramps. When we go to the Rutherford 5, Rutherford 6 stage of critical limb ischemia means that the patient is affected by what we call tissue loss. That means there's some ulcer or some major necrosis in case of Rutherford 6 which affect the patient. Usually these patients are affected themselves by diabetes, patients are on dialysis, patients are, you know, a very a very strong smoker. And there are some few conditions which are genetical, which can affect the below the knee vessels, but I mean these are the minority of the patients. So patients with tissue loss are the ones who are more in need to be treated and they need to be very well assessed in a very good timely manner. For the NHS, for example, we set up a window of 14 days for the first diagnosis to the treatment in order to save as much tissue as possible because time is tissue as the neurologists say when they talk about the stroke.