Introduction To All Leg Ulcers

The prevalence of leg ulcers (Venous, Arterial, Mixed ulcers, Diabetic (foot, not leg) and autoimmune ulcers) in the Western world is 0.11–0.18%. There is a 2.8:1 female to male ratio, with venous disease being the main cause of ulceration. The risk of leg ulceration rises with age. The estimated cost in the UK of all leg ulcers is £200–600 million, with the costs of individual ulcer treatment between £557 and above, anually. Between 60% - 90% of patients are managed in the community (17).

 

The Money

The cost of treating a pressure ulcer varies from £1,214 (category 1) to £14,108 (category IV) per ulcer. Costs increase with ulcer severity because the time to heal is longer and the incidence of complications is higher in severe cases (18). Posnett and Franks considered the UK national cost of pressure ulcers to the NHS to be between £1,760 million and £2,640 million each year, making pressure ulcers the most costly chronic wound to the Health Service (19).

 

Epidemiology

They are defined as a localised injury to the skin and/or underlying tissue usually over a bony prominence, as a result of pressure, or pressure in combination with shear forces. The prevalence of pressure ulcers across five European countries was 18.3% in 2007 (17). They commonly occur at the sacrum and heels. Other common sites are the buttocks, ankles, elbows and hips. Most pressure ulcers are Category I or Category II pressure ulcers (19).  

 

Aetiology

Pressure ulcers caused by external pressure on tissues leading to decreased capillary flow, ischaemia and capillary thrombosis, if sustained. This therefore results in fluid escaping from the vasculature into surrounding tissues causing oedema, accumulation of metabolic waste, hypoxia and cell death. The types of pressure are: capillary closing, vertical, tissue interface pressure, and shear and friction forces. Other factors that may contribute to the development of the damage are reactive hyperaemia, reperfusion injury, patient age (extremes of age most at risk), nutritional status and weight (extremes of weight most at risk), mobility status, condition of peripheral circulation and continence status. Sacral damage often occurs whilst sitting in a chair with shear forces causing the most damage. Injury to other areas is more likely to be due to direct pressure over a bony prominence. In acutely ill patients, equipment such as nasal cannula can even cause pressure damage to the nose (17). 

 

Clinical Signs

Early signs of damage may present as a red area on the skin that remains after the pressure has been relieved, or appear as broken skin or an abrasion. Pressure ulcers are classified under four stages. Category/stage i: Non blanchable redness of intact skin - Intact skin with non-blanchable erythema (if light pressure is applied on an area it turns white in normal tissue. Once the pressure is released it returns to normal very quickly. Where damage is present, the tissue does not turn white) of a localised area. Discolouration of the skin, warmth, oedema, hardness or pain may also be present. Darkly pigmented skin may not have visible blanching but may be painful, firm, soft, warmer or cooler as compared to adjacent tissue. Category/stage ii: Partial skin loss or blister - Partial thickness loss of dermis presenting as a shallow open ulcer with a red pink wound bed, without slough. May also present as an intact or open/ruptured serum-filled or serosanguinous (containing or relating to both blood and serum) filled blister. Category/stage iii: Full thickness skin loss (fat visible) - Full thickness tissue loss. Subcutaneous fat may be visible but bone, tendon or muscle is not exposed. Some slough may be present and may include undermining and tunnelling. Category/stage IV: Full thickness tissue loss (muscle/bone visible) – Full thickness tissue loss with exposed bone, tendon or muscle. Slough or eschar may be present (17).

 

Treatment

This will depend on the category/stage of the damage, but there are interventions common to all patients in the NICE guidelines, and these include: Appropriate support surface (mattress and cushions) to redistribute pressure and reduce shear forces, specific turning schedules, wound cleansing with normal saline or potable water, debridement of dead or devitalised tissue, appropriate dressings, treating infection and skin hygiene, particularly in incontinence. Negative pressure therapy may be a suitable adjuvant therapy. Surgical reconstruction occurs in complex cases. Other therapeutic interventions include electrical stimulation, laser therapy and ultrasound (17).