In venous leg ulcers, the incompetency of venous valves means there may be backflow in the veins of the lower leg which results in venous hypertension. This can cause fluid to accumulate in the tissues, developing oedema.
Brown haemosiderin staining is caused by the breakdown of red blood cells which become trapped in the skin. Induration occurs from fibrosis of the subcutaneous layer which may result in a classic ‘champagne leg’. Other venous symptoms are varicose eczema, oedema, ankle flare (distended veins in medial ankle area) pain (with relief on elevating the limb), varicose veins, ulcers in gaiter or malleolus regions.
Risk factors of venous ulceration are: DVT, varicose veins, swollen oedematous legs, multiple pregnancies, lower leg fracture, thrombophlebitis, previous leg ulceration, previous vascular or orthopaedic surgery.
Arterial signs include: reduced or absent pedal pulses, history of intermittent claudication, reduced ABPI, deep punched out ulcers on toes, heels or foot, necrosis or gangrene, loss of hair to the limb, shiny, pale hairless skin on shin, dusky coloured foot, cool to touch, thickened toe nails, pain in feet and blanching when elevated, delayed capillary refill.
Risk factors for arterial ulcers include ischaemic heart disease, smoking, hypertension, diabetes mellitus, TIA/CVA, MI or angina, rheumatoid arthritis or previous arterial surgery.
Compression bandaging used in treatment of venous leg ulcers is designed to aid venous return. Laplace’s law is that the pressure applied to the limb is determined by the width of the bandage, the degree of overlap and degree and technique of stretch applied (usually both 50%) but this is dependent on the ankle being smaller than the calf. Shortstretch bandaging is different in that it is applied at 100% stretch.
- 80% of leg ulcers are venous
- Venous ulcers are caused by chronic venous insufficiency; pooling in the leg leads to venous congestion, leading to fluid being forced out of the vessel and into the surrounding tissues as oedema.
- Erythrocytes leaking through into the tissue can stain the leg, a symptom of chronic venous disease.
- Oedema can also be caused or exacerbated by renal or cardiac conditions, and therefore their involvement needs to be ascertained as part of care planning.