In the UK, the lower limb amputation rate has not improved significantly since 2012, and is contributed to heavily by the high incidence of infection and ischaemia in patients with diabetic wounds. Michael Edmonds (King’s College Hospital , London, UK), a specialist in the treatment of the diabetic foot, turns his attention in this article to the importance of preventative practices and interdisciplinary approaches, as well as explaining how a simple tool can help to improve the standard of care for all patients suffering from limb-threatening chronic wounds.
The term ilegx represents an interdisciplinary leg initiative which was founded at the Charing Cross Symposium (London, UK) in 2008. A key goal of ilegx is to encourage interdisciplinary collaboration that spans primary and secondary services, as well the development and implementation of best practice approaches to save legs. Now in its 12th year, ilegx will be part of iWounds at the CX Symposium (21–24 April, London, UK) in 2020.
This ilegx philosophy aims to accomplish the early diagnosis of the causes of leg and foot tissue loss and to promote interdisciplinary collaboration in the management of these conditions. The development of this philosophy led to the creation of an ilegx algorithm, which encompasses both the diagnosis and definitive management of leg and foot tissue loss, dividing the aetiologies into vascular and non-vascular causes. The category of vascular ulcers (70%) comprises ischemic arterial, renal arterial, diabetic arterial, inflammatory, venous and lymphatic ulcers, caused by derangement of macro- as well as microvascular pathophysiology; non-vascular ulcers (30%) are caused by non-arterial diabetic pathological changes, pressure and a variety of other causes.
Illustrated in the shape of a turning wheel, the ilegx algorithm highlights diagnostic approaches to wound care and reminds specialists of key management steps, identifying which disciplines should be included in the circumstances of a particular diagnosis. It is, above all else, a useful tool which simplifies this highly complex disease area. The “ilegx wheel”, as shown in Figure 1, was developed with the goal of clarifying the interdisciplinary nature of the causes leading to leg and foot tissue loss, and is designed to speed up patient referral in order to prevent this.
Once the correct diagnosis is made, the “ilegx wheel” is set to the respective causation/slice. Consequently, the “ilegx” wheel provides a specific indication of how to manage a specific case of leg or foot tissue loss using the patient’s diagnosis. It also determines the players who will be involved in the interdisciplinary team at hand. Figure 2 shows the management steps and interdisciplinary team needed to treat the ischaemic arterial ulcer.
With there being more than 40 reported causes of leg and foot tissue loss, patients can suffer from this condition with either a single aetiology, or with multiple causes. It is hoped that the ilegx approach will unravel the aetiologies of leg and foot tissue loss, in order to diagnose and treat patients more effectively
As an example of the ilegx approach, the management of the diabetic foot ulcer can be summarised according to the wheel. A diabetic foot ulcer is a sign of systemic disease and successful management requires the expertise of an interdisciplinary team who can provide integrated, focused care in a diabetic foot clinic. The team has to be aware of three distinct pathologies in the diabetic foot—neuropathy, ischaemia and infection—but on a practical level, the diabetic foot can be divided into two entities; the neuropathic foot with its characteristic plantar neuropathic ulcers, and the neuroischaemic foot with its ulcers on the margins of the foot.
Members of the team will include a podiatrist, nurse, orthotist, radiologist, microbiologist, vascular scientist, surgeon and physician. It is helpful if the team works closely together, within the focus of the diabetic foot clinic, and also meets regularly for joint ward rounds and X-ray conferences. Each team member should be available quickly in an emergency, though some roles may overlap depending on local expertise and interest. Furthermore, all members of the team must realise that neuropathy often delays the patient’s presentation, because they will not have pain and may not take the lesion seriously. This is a mistake that can also be made by medical attendants, who have been educated in a diagnostic process that assumes pain is a reliable indicator of the seriousness of the presentation. This is not true in the diabetic foot.
Day-to-day interdisciplinary treatment is carried out by podiatrist, nurse, orthotist and physician in the diabetic foot clinic. Further interdisciplinary management can be achieved by holding regular joint clinics when appropriate groups of patients are assembled in the diabetic foot clinic. These are held regularly with vascular, orthopaedic and plastic surgeons, and through these specialist clinics, it is possible to organise a ‘fast-track’ service with a ‘one-stop’ visit. In the joint clinic with the vascular surgeon, the need for angiography and angioplasty can be rapidly agreed upon and promptly carried out as a day case where appropriate. The results can be quickly reviewed and further action taken thereafter.
The diabetic foot clinic should provide rapid access, early diagnosis and a prompt solution for patients with foot problems. Emergency services can be run concurrently with routine clinics so that patients with new ulcers, pain or discolouration can be seen the same day. Rapid admission to hospital for the foot in jeopardy can also be arranged through this emergency service.
It is important to realise that a combination of neuropathy and ischaemia can be devastating. There is a disconcerting speed of the natural history and a wide range of comorbidities are found in patients presenting with both conditions, making these neuroischaemic patients extremely vulnerable. Furthermore, by the time that the peripheral arteries are involved, the ischaemic patient is likely to have neurological and vascular impairment elsewhere. It is also important to be aware that neuroischaemic feet need long-term care and follow up.
Care of the neuroischaemic patient also involves routine preventive foot care, the updating of education in order to avoid trauma, diagnosing problems early, rapid and aggressive care of ulcers, regular arterial and graft surveillance, and the provision of statins and aspirin for secondary prevention of arterial disease. Thus, the long-term follow up care of the diabetic patient with peripheral vascular disease is an essential component of successful management, and staff, patients and administrators need to be aware of this. The ideal forum for management of the acute episodes of infection and ischaemia is a combined vascular/diabetic foot clinic.
Aggressive treatment of infection is important both in the neuropathic foot and the neuroischaemic foot, starting with wide spectrum antibiotic therapy and then targeted therapy according to the bacteria isolated. It is important to have a working knowledge of the principal bacteria and their local antibiotic sensitivities, including awareness of the prevalence of resistant organisms. However, in every patient, individual sensitivities of each organism isolated on culture should be sought to guide rational antibiotic therapy. There should also be close cooperation between the microbiology laboratory and the diabetic foot service, while antibiotic therapy should be accompanied by debridement of infective and necrotic tissue.
The majority of major amputations are preventable, and early referral and interdisciplinary working are the key to saving legs, as well fulfilling the ilegx vision of significantly reducing the number of lower limb amputations.
Michael Edmonds is a professor of diabetic foot medicine at King’s College, London, UK, and consultant physician, King’s College Hospital, London, UK.