The skin is the largest organ in the human body, weighing about 3 kg (Bianchi and Cameron, 2008; Bonifant and Holloway, 2019), and serves multiple functions. It provides barrier protection for the entire body, preventing organisms and toxins from entering the body and preventing damage to internal organs and tissues. It also protects against damage from ultraviolet radiation and strong sunlight, and helps regulate the body's temperature. Additionally, the skin provides sensory input, and stores fat, water and vitamin D (Lavers, 2017).
Anatomy of the skin
The skin is at its thickest on the palms of the hands and soles of the feet and thinnest on the eyelids (Lavers, 2017). It comprises three separate layers—the epidermis, the dermis and the hypodermis—all of which are important to its proper functioning (Figure 1).
The epidermis is the outermost layer of the skin and forms the main protective barrier, preventing the entry of organisms and substances into the body and loss of water from the body (Yung, 2017). It also helps regulate body temperature, protects against ultraviolet light and metabolises vitamin D (Lavers, 2017). The epidermis is made up of three types of cells, namely, keratinocytes (skin cells), melanocytes (pigment-producing cells) and Langerhans cells (immune cells). Thus, the Langerhans cells are the body's first line of defence.
The dermis lies under the epidermis and provides the fibrous connective tissue function of the skin (Yung, 2017). It comprises two types of cells: collagen fibres and elastin cells. Collagen fibres have a high degree of tensile strength and ensure the skin's stability, while elastin is responsible for elasticity and flexibility. Hair follicles and sweat glands are also found in the dermis (Yung 2017). The dermis is thinner in women, and its thickness decreases considerably after menopause (Bonifant and Holloway, 2019).
Lastly, the hypodermis is the bottommost layer, mainly composed of fat cells (adipocytes), with nerves and blood vessels running through it. It is often referred to as subcutaneous tissue (Yung, 2017), and it is also thinner in women than in men (Lavers, 2017).
Effects of ageing on the skin
Like all body functions, skin integrity decreases with age, with the epidermis and dermis being directly affected. There is a reduction in the numbers of all three component cells in the epidermis, which results in it becoming flatter and more regular shaped; its loses its troughs, which results in it becoming fragile and more easily damaged (Bonifant and Holloway, 2019). The loss of these cells also impacts on the barrier function of the epidermis.
Similarly, the numbers of collagen fibres and elastin cells in the dermis also reduce with age, leading to loss of skin strength and flexibility and leaving it at increased risk of damage (Bonifant and Holloway, 2019). While the thickness of the hypodermis does not reduce significantly with the ageing process, this layer is at higher risk of damage in older skin because of the effects of ageing on the two layers above it.
Because of the reduction in the numbers of component cells and the subsequent loss of function, older skin takes longer to heal after an injury or tear (Bonifant and Holloway, 2019).
Factors that impair skin integrity
Ageing is the main factor that impairs skin integrity (Bonifant and Holloway, 2019), but it is not the only one. Long-term steroid use can leave the skin fragile and thin (often referred to as ‘paper skin’ or ‘tissue paper skin’). Further, drug reactions can damage integrity and cause rashes and urticaria, which damages the epidermis. Some adverse reactions, such as oedema, can even affect the deeper parts of the skin (Bianchi and Cameron, 2008). Although drug reactions can occur at any age, there is an increase in polypharmacy in older people as more than one long-term condition may need managing (Bianchi and Cameron, 2008).
Chronic skin conditions, such as eczema and psoriasis, have lasting effects on skin integrity (Burch, 2017), and long-term conditions such as diabetes, peripheral arterial disease and venous insufficiency are known to impair or delay wound healing. Prolonged exposure to ultraviolet radiation, through holidaying, working outdoors and regular sunbed use, also causes skin damage. Similarly, cold weather can cause the outer layers of the skin to dry out with a loss of moisture. Additionally, in cold weather, there is increased use of heating, which produces a dry environment and exacerbates the moisture loss (Bonifant and Holloway, 2019).
In those with incontinence, urine and faeces when left in contact with the skin for long periods can cause incontinence-associated dermatitis (Payne, 2015), which impairs skin integrity. Further, urine can macerate the skin, leaving it weaken and at risk to damage (Hampton, 2013). Another factor indirectly related to skin damage is falls, which can result in bruising, skin tears and even traumatic wounds. As people age and long-term conditions progress, they experience an increased risk of falls (Hampton, 2013).
Lastly, the use of soap can affect the skin. The skin has a mean pH of 5.5 but most perfumed soaps have pH values of 9.5–10.5; this difference in pH can cause moisture loss from the skin, leaving it dry and fragile (Cooper and Gray, 2001).
Although most of the factors listed above can come into play at any time of life, their effects are worse with advanced age, and an older person is likely to have been exposed to these for longer than someone younger.
Why skin integrity is important in pressure ulcer prevention
Immobility and direct pressure are the main causes of pressure ulcers (National Institute for Health and Care Excellence (NICE), 2014) (Box 1), but poor skin integrity can also be a risk factor (Benbow, 2009). Damaged and/or fragile skin does not have the elasticity, thickness and strength to resist pressure and shearing forces. Therefore, good skin care and maintaining skin health can be important in preventing pressure ulcers.
How can skin integrity be maintained?
Skin cleansing and daily application of emollients can help to maintain skin integrity, and soap should be avoided because of the dehydrating effect it can have on skin (Cooper and Gray, 2001; Stephen-Haynes and Stephens, 2013). pH-neutral soap substitutes and gentle skin washes should be used instead. Daily use of emollients can help ensure a moisture balance in the skin by restoring any lost moisture, preventing further moisture loss and helping to maintain the skin's elasticity, flexibility and barrier function.
The best way to achieve good skin care is to introduce it into a person's daily bathing/showering routine. If they maintain their own hygiene, then they should be encouraged to wash with a pH-neutral soap substitute and then apply an emollient. If their hygiene is provided by someone else, such as a relative or carer, then the benefit of this regimen should be promoted. This can be particularly challenging in the case of older men, as they may view the regimen as being un-masculine, so special attention may be required in promoting the regimen.
If the person has faecal and/or urinary incontinence, or their skin is damaged by moisture, for example, due to sweat, wound exudate or a leaking stoma, then an extra layer of protection will be required. Barrier creams and sprays are an effective way of protecting skin from excessive moisture (Stephen-Haynes and Stephens, 2013). They are called so because they form a physical barrier between the skin and the moisture. It should be noted that zinc-based barrier creams should be avoided because they can block the skin's pores and can coat the inside of incontinence pads, thereby reducing their absorbency (Payne, 2015). Non-petroleum-based creams and sprays, such as Sorbaderm and Cavillon, do not cause these problems and still provide an effective barrier against moisture. Barrier creams or sprays should be applied after the skin has been cleansed and moisturised. Further, they should only be applied to areas of the skin that are affected by moisture.
Issues with accessing certain parts of the body
The majority of older people manage their own skin hygiene, but physically, they may not be able to reach all parts of the body. For example, the back and buttocks can often be problematic places to reach. Further, the feet, particularly the soles, the back of the legs and shoulders can all be places that require physical dexterity to reach. Additionally, areas in between skin folds may be missed.
In such cases, physical aids can assist the person in reaching these difficult places. A long-handled sponge is a simple, inexpensive and easily available aid that can help a person cleanse and moisturise their body. If more complicated aids are required, the person may need a referral to an occupational therapist.
If a person's hygiene needs are being met by a relative or a carer, then it should be ensured the skin all over the body is being both cleansed and moisturised, and not just moisturised where the carer considers the skin to be dry.
Other factors affecting self-care
A person's ability to manage their skin-care regimen or their carer's ability to manage it for them may be affected by other factors. These cultural and physiological factors should not be dismissed as minor, as for some people, they can be very serious. These include:
Assessing skin integrity
Assessment is an important part of identifying skin integrity issues, as well as the underlying causes. Bonifant and Holloway (2019) recommended visually examining the skin and looking for unusual colour, temperature, texture and skin integrity (Table 1).
| To assess | To consider |
|---|---|
| Colour |
|
| Temperature |
|
| Texture |
|
| Integrity |
|
The assessment should also consider whether there are any underlying factors that affect skin integrity, such as:
Once the assessment is complete, a multidisciplinary approach should be adopted to managing the underlying problems identified, involving other professionals as appropriate. This would include a medication review to determine, for example, whether the person needs their pain better controlled, and a long-term condition review, to determine whether these conditions are being managed well or if the patient needs a referral to a specialist nurse or doctor. If the person is experiencing repeated falls or needs help to become more mobile safely, it should be determined whether the person needs a referral to a falls or physiotherapist service, respectively. A referral to an occupational therapist may be needed to provide the patient with access to special aids or adaptations, and the appropriate team (council, housing association or landlord) may need to be contacted if the house is too hot or cold. Lastly, community nurses should identify changes to the person's lifestyle that could improve their skin integrity, for example, establishing a hygiene regimen, ensuring adequate fluid intake, turning central heating up or down as appropriate and increasing daily exercise or movement in keeping with the person's ability.
NICE guidance (2014) recommends regular skin monitoring for any signs of pressure damage, but signs of skin integrity problems should also be looked out for (Bonifant and Holloway, 2019). With pressures on district nursing services and shortages of staff, this might not always be possible. Community nurses have limited time to spend with their patients and are rarely involved in personal hygiene. Therefore, it is important for them to educate patients and their carers or relatives on skin integrity and the measures they can take to improve it, and the latter should be encouraged to seek advice if any concerns arise, especially if they observe any skin damage or breaks. It is also vital for community nurses to build a relationship of trust with the carers or relatives of their patients, by responding to their problems or concerns and taking them seriously. In this manner, skin integrity issues can be identified in a timely manner and delays in treatment can be reduced.
Conclusion
The skin provides many vital functions for the body, and without good skin integrity, a person's health can be severely damaged. Importantly in the case of older adults, healthy skin can adapt to pressure more effectively than damaged or impaired skin. Poor skin integrity should not be seen as a normal consequence of ageing or a disease process, and active steps should be taken to help improve it.
Undoubtedly, impaired skin integrity cannot be managed if the problem is not identified. This highlights the importance of regular, full skin assessment by physical examination of the skin and seeking to identify any underlying causes and external factors that may affect skin integrity.