Never amputate without consultation of a vascular surgeon.

Abstract

Lower limb ischaemia is one of the determinants in the development of diabetic foot ulcers and the most important factor preventing their healing. There are a number of misleading factors masking the presence of atherosclerotic disease and tissue damage; these are reduced inflammatory response to infection, autosympathectomy and mediasclerosis, which all diminish the clinical suspicion of ischaemia. Therefore, adequate assessment of the lower limb circulation should be routinely performed in complicated diabetic foot. This evaluation can often be made with simple methods. In addition to clinical examination ankle/brachial pressure index, systolic toe pressure, plethysmographic pulse volume recordings and simple hand-held Doppler auscultation are most often sufficient to make a decision as to whether angiography is needed or not. Duplex examination can give more profound information on the severity and extent of arterial occlusive disease, but the method is strongly user-dependent. Early vascular consultation is mandatory in diabetic foot work-up and should be undertaken within 2 weeks if a new skin lesion shows no tendency to heal. Long bypass grafting procedures and microvascular free flap techniques have been shown to achieve excellent results in relieving critical leg ischaemia, even in the presence of large foot lesions, and should be used to prevent major amputation. The timing of various procedures is a controversial issue. Feet with small ulcers or restricted dry gangrena can be revascularised first, with minor amputations and local surgery of the ulcer being done thereafter. In the septic neuroischaemic foot, major amputation may be unavailable but if the infection is not immediately life-threatening the infected part of the foot should be drained and debrided properly and left wide open, sometimes with a guillotine amputation in order not to risk the bypass graft, which can be done a couple of days later.