VOL: 96, ISSUE: 45, PAGE NO: 35
Martyn Butcher, RGN, DipHSW, CertMHS, is tissue viability clinical nurse specialist, Plymouth Hospitals NHS Trust
Maceration of the skin around wounds is a common wound care problem.
At best it can cause patient discomfort and irritation, at worst it can lead to ulceration and the extension of damage into previously unaffected tissues.
Under normal circumstances, epidermal tissue forms an effective barrier against the rigors of the external environment. It protects the body from fluid loss, bacterial attack and the effects of external forces. However, in certain situations this barrier is ineffective and the defence mechanism is breached, in particular after prolonged exposure to moisture or corrosive body fluids.
Prolonged exposure of the skin to high levels of moisture can result in acute maceration. The outer, flattened and keratonised layer of epidermal cells becomes rehydrated, causing swelling, and the bonds between the tissue planes weaken. This drastically alters their ability to withstand damage, particularly friction.
In severe cases the outer layer of the epidermis is stripped away, exposing the fragile germinative layers. This causes pain and increases the risk of damage and significant secondary infection from bacteria and fungi, which multiply in the moist, protein-rich medium.
When exposure of the germinative layer has occurred, efforts to correct the damage by drying can have very serious implications. Wiping the over-hydrated epidermis causes further mechanical skin stripping and the exposure of the tissue to the air leads to desiccation. These basal cells leak serous fluid which, if left, will form a dry eschar. The drying of the germinative tissues will lead to progression of the damage to the deeper layers.
The epidermis also cannot withstand a number of enzyme-rich fluids, including small bowel effluent and pancreatic secretions. These can strip epidermal tissue rapidly as their proteolytic enzymes break down the cell matrix. Contact with these potent chemicals is usually limited, but small bowel fistulae or persistent and profuse diarrhoea can cause severe superficial skin loss, as can wound exudate from chronic ulcers (Wysocki et al, 1993).
Exposure to urine and faeces as a result of continence problems is a more common occurrence. Fresh soiling that is cleaned promptly tends not to cause serious problems, but if cleaning is delayed the metabolising of urea by skin flora produces by-products with a high pH.
Skin pH is normally 5.5-5.7, which protects against pathogenic bacterial colonisation (Anthony, 1993). By contrast, an alkaline environment reduces the body’s defence mechanism. Specific skin sensitivities can also arise from prolonged contact with exudate and effluent, causing conditions such as contact dermatitis (Cameron and Powell, 1996).
Dealing with maceration poses a number of problems:
- Pain - affected tissue is invariably highly sensitive because of the inflammatory nature of the damage. Preparations that contain alcohol or other irritants are not tolerated (Rolstad et al, 1994) and their cytotoxic nature may compromise tissue integrity further;
- Excessive moisture - continued exposure to moisture can cause protective barriers to wash off or become diluted to such a degree that they lose their effectiveness, permitting further damage;
- Product application - the loss of superficial epidermis and the presence of surface moisture precludes the use of most adhesives in wound dressings. This is exacerbated by the fact that many affected areas are difficult to dress, for example, those that are adjacent to wounds, in the perianal margin or around structures such as stomas;
- Interaction with other treatments/ appliances - it is important that any product used to protect the skin does not interact or interfere with other products. For example, oil-based barrier creams or ointments and zinc paste preparations prevent the application of adhesive dressings and limit the absorptive quality of continence products.
For the clinician to overcome the problems posed by maceration, the method of management needs to comply with a number of conditions. The treatment must:
- Be easy to apply in a variety of situations;
- Not cause further trauma on application or removal;
- Not interact with existing dressings or continence products;
- Not increase the risk of bacterial contamination of wounds;
- Effectively protect tissues from moisture/chemical attack;
- Be non-sensitising.
The management and prevention of maceration must focus on the reason the skin is coming into contact with excess moisture. If urinary continence problems are the main issue, bladder and bowel function need to be improved or mechanical methods such as indwelling catheters should be used.
Wound exudate can be channelled away from the wound through appliances such as fistula drainage bags or by applying negative pressure to the wound area (Young, 2000).
Excess wound exudate can be reduced by eliminating infection and critical colonisation, if this is the cause (Cooper and Lawrence, 1996), or the use of compression to correct venous and capillary congestion (Cutting, 1999; Thomas et al, 1996).
If contamination of the skin is unavoidable, prolonged contact should be prevented. Highly absorbent dressings and continence pads should be used to draw moisture away from the skin and should be changed frequently. Alginate, hydrocellular foam and hydropolymer dressings are all effective in managing wound exudate (Young, 2000; Cutting, 1999; Thomas, 1990; Jones and Milton, 2000).
Several products can be used to prevent the over-hydration of the cornified epidermis, such as oil-based creams and zinc paste preparations.
The latter, however, have been linked to the development of skin sensitivities (Morison et al, 1999), and the greasy nature of all these products can prevent the application of adhesive dressings and interfere with the absorptive properties of foams and continence products.
Liquid film dressings, which are made up of synthetic polymers suspended in a solvent, can be used as an alternative to creams. On application the solvent evaporates, leaving a film of polymer. These products have been available for years, but until recently their popularity was limited by the fact that they relied on alcohol as the solvent. After a clinical evaluation (Box 1), my own trust has started using a new film dressing which uses an alcohol-free solvent.