Management of venous leg ulcers
CLEANSING AND EMOLLIENT THERAPY
Good skincare (washing and emollient therapy) is paramount in managing venous leg ulcers. Emollient therapy has two different modes of action:
- PASSIVE – emollients are lipids that occlude the skin surface, thus preventing water loss from the epidermis
- ACTIVE – Moisturisers are lipid emulsifiers that actively hydrate the skin by the application of a humectant to the surface of the skin.The active mode of action is the movement of water from the dermis to the epidermis
Emollients work to moisturise the skin by increasing the amount of water held in the epidermis. This occlusion for passive emollient therapy is achieved if greasy substances such as petrolatum are used. The active mode of action is the movement of water from the dermis to the epidermis. As the emollients increase the amount of water in the epidermis and make the skin less dry, they also have an anti-pruritic effect which is often beneficial to people wearing compression or hosiery.
The key aspect of skin care for the lower limb affected by venous disease and associated oedema is for the clinician to recognise underlying skin conditions, such as varicose eczema, lipodermatosclerosis or hyperkeratosis, and treat appropriately and continuously. The application of emollients will keep the skin supple and this regimen should ideally be continued indefinitely. Ointments are likely to produce fewer adverse reactions as they contain fewer sensitisers compared to lotions, gels and creams and therefore are a better choice in treating people with varicose eczema (moderate to strong potency topical steroids are also sometimes needed short term to treat the eczema).
Note to prescribers regarding Aqueous cream – sodium lauryl sulphate (SLS) (a component of aqueous cream) is a detergent and surfactant and has been used extensively for its thickening and emulsifying properties. However, recent studies have shown that it should not be used as wash product or leave-on emollient as it has potential to damage skin and compromise barrier function.
EWMA Statement 5.3.g: Concerning management of the surrounding skin, topical barrier preparations to reduce erythema and maceration from VLUs should be considered. Venous eczema can be treated with short-term topical steroids.
2. INFECTION IN VENOUS LEG ULCERS
Treatment of infection Statement 5.2.e: Bacterial swabs should not be taken routinely unless clinical signs of infection are present which include:
- New or increased wound pain
- Delayed healing
- Friable or hypergranulation tissue
- Increased heat
- Increased odour from the wound
- Increased white cell count
- Increased localised swelling
Before taking a wound swab, ensure the ulcer is cleaned with tap water.
The diagnosis of wound infection should be made on the clinical presentation and accompanying blood results. However if guidance on antibiotic prescribing is required the wound swab result will aid this decision making process.
The use of topical antibiotics is not recommended
Use of topical anti-microbial dressings are advocated for a local infection or prophylactically for a 2-week period for prevention in wounds at high risk (diabetic foot ulcers) for example, honey, silver, cadexomer iodine and PHMB.
Patients with infection should be followed up every 2-3 days until clinical improvement is seen. This would be suggested by reduction in inflammation, development of red healthy granulation tissue, reduction of exudate and pyrexia and pain..
If infection is not resolving, revisit the wound swab result and consider changing the antibiotic based on sensitivity recommendations. NICE guidance on leg ulcer infection and antimicrobial prescribing was issued in February 2020
3. PAIN ASSESSMENT
Use a reliable pain assessment tool – for example the Visual Analogue Scale (VAS) to record severity and frequency of pain and also assess the impact of pain the on patient’s day to day activities
When considering how to dress wounds, consider the 4 basic principles of the TIME acronym:
Tissue – assess the tissue type and remove any dead tissue in order to encourage the formation of healthy granulation tissue
Inflammation and infection – look for any evidence of infection and treat appropriately
Moisture balance – vital to successfully manage exudate (wound fluid) to maintain a moist wound environment which is essential for optimum healing
Edge – remove any scabs which will be a barrier to the progression of new epidermis across the wound bed This can be done either manually or by using a hydrocolloid dressing or an alternative that donate moisture to the wound bed.
EWMA Statement 5.3.f: simple non-adherent dressings are recommended for the majority of small and non-complicated venous leg ulcers.
However, a suitable dressing is needed to treat a particular problem. If the wound appears infected, an anti-microbial dressing can be used for a maximum of two weeks then review.
If the wound base contains dry slough or necrotic tissue, a dressing that will hydrate the wound and de-slough should be used such as a hydrocolloid or hydrogel. Absorbent or super absorbent dressings should be used if exudate levels are high with frequent dressing change.
The peri-wound skin needs to be protected from maceration with a barrier cream/spray and if dressing is particularly painful, consider silicone dressing for atraumatic removal.
EWMA Statement 5.3.a: Compression therapy is recommended over no compression in patients with VLUs to promote healing
Correctly applied compression therapy is the cornerstone of treatment and has been demonstrated to improve the healing rates in patients with existing venous leg ulcers. Compression garments or bandages, applied externally to the lower leg, increase the pressure on the skin and underlying structures, thus improving venous return and thereby helping to relieve the symptoms in the lower limb (such as oedema and chronic venous insufficiency).
Graduated compression bandaging is used to treat active ulcers with the highest pressures (40mmHg) at the ankle and the pressure reducing towards the knee (20mmHg). There is a large choice of options available for delivering suitable compression. If a two or four component bandage system cannot be tolerated, there are leg ulcer hosiery kits or wrap systems (which allow patients to self manage as do not require application by a health care professional), which may be more appropriate.
The direct application of pressure to a limb is measured in mmHg. The amount of pressure required is determined by underlying pathologies as well as the patient’s ability to tolerate compression.
EWMA Statement 5.3.b: in patients with VLU strong compression over low compression pressure is recommended to increase healing
Classification of pressures:
Mild - <20mmHG
Moderate – 20 – 40mmHG
Strong – 40-60mmHG
Very strong - >60mmHG
Pressures of >40mmHG are recommended for the treatment of venous leg ulcers, but this may not be possible in frail or elderly patients. Resting pressures of >60mmHG should be reserved for patients with lymphoedema.
The EVRA study has demonstrated a reduction in recurrence if the patient is referred for surgical intervention early in their venous leg ulcer presentation https://www.nejm.org/doi/full/10.1056/NEJMoa1801214 (accessed 15/12/2020)
EWMA Statement 5.3.d: In patients with mixed ulcers, we suggest applying a modified compression in patients with less severe arterial disease: ABPI >0.5
The patient’s ABPI is a major factor in determining the levels of compression that can be tolerated. Patients who have compromised arterial circulation will need lower levels of compression to avoid the risk of pressure damage or exacerbating ischaemia. Reduced compression systems are available to be safely used in patients with arterial disease (ABPI between 0.5 to 0.8)
World Union of Wound Healing Societies (WUWHS). Principles of best practice: Compression in venous leg ulcers. A consensus document. London: MEP Ltd, 2008