Maintaining skin integrity

Alleviating pressure
The focus of pressure ulcer prevention remains the mitigation of the effects of immobility despite some uncertainty regarding the precise nature of pressure sore aetiology (Clark, 2001). Specifically, this requires reducing the time of weight bearing of the body’s bony prominences, through repositioning or using support devices, such as air pressure alleviating mattresses. The latter may also reduce the magnitude of the forces applied during tissue loading. Guidelines from EPUAP (2008) highlight the importance of the following key preventative strategies (see Box 4.2). The new guidelines from EPUAP and the National Pressure Ulcer Advisory Panel (NPUAP) are due to be published soon (www. epuap.org and www.npuap.org, respectively).

Box 4.2 Key pressure ulcer prevention strategies based on EPUAP guidance (1998) (1) Systematic risk assessment, using tools combined with clinical judgement, (2) Maintaining and improving tissue tolerance to pressure to prevent injury by conducting skin assessment of the bony prominences and skin condition (dryness, cracking, erythema, maceration, fragility, heat and induration) and optimising the skin’s condition (e.g. reducing excessive moisture), (3) Minimise friction and shear forces through correct positioning and transferring techniques, (4) Identify nutritionally compromised individuals through assessment and plan for nutritional support to meet individual needs, (5) Improve the patient’s activity level where possible, (6) Protect against the adverse effects of external mechanical forces: pressure, friction and shear through frequent and correct repositioning and the use of suitable support surfaces, and (7) Education directed at health professionals, patients, family and caregivers (e.g. teach able patients to redistribute weight every 15 minutes).

The Panel for the Prediction and prevention of Pressure Ulcers in Adults published by the Agency for Health Care Policy and Research (AHCPR) (1992) reflects guidance of US national importance. They recommend that patient repositioning be performed ‘at least every 2 hours’. Discussions on the issues related to prevention through patient turning are examined effectively (Clark, 2001). The EPUAP website in 2008 indicated that their own and the AHCPR guidelines remain the current internationally recognised ones available, although they acknowledge these need updating.

Support surfaces such as pressure-relieving beds, mattresses and seat cushions may be used as aids to prevent pressure ulcers both at home and in institutions. The evaluation of pressure-relieving support surfaces has investigated such support systems through a rigorous trial (‘PRESSURE’) (Nixon et al., 2006) and a Cochrane review (McInnes et al., 2008). The PRESSURE trial undertaken for the Health Technology Assess ment programme was a multicentre, randomised controlled parallel group trial. They found no difference between alternating pressure mattress replacements and overlays in terms of the patients developing new pressure ulcers (Nixon et al., 2006). However, alternating pressure mattress replacements were found more likely to be cost saving. It is suggested that patient preference can be supported without risk, if they prefer an overlay to a replacement mattress. The review by McInnes et al. (2008) aimed to assess the effectiveness of support surfaces in the prevention and treatment of pressure ulcers. They concluded that higher specification foam mattresses should be considered rather than standard hospital foam mattresses. They propose that organisations consider the use of pressure relief for high-risk patients in the operating theatre, as this is associated with a reduction in the post-operative incidence of pressure ulcers. The review also suggests that the evaluation of seat cushions is limited.

Assessing and limiting the effects of incontinence on the skin
Incontinence is identified as a risk factor in many published pressure ulcer assessment tools (Norton et al., 1962; Gosnell, 1973; Waterlow, 1988). Tools such as the Braden Scale (Bergstrom et al., 1987a, b) specify the moisture factor, considering sweat and or incontinence as possible sources. The literature includes analyses of the rigour by which risk can be predicted (e.g. Haalboom et al., 1999). The review by Cullum et al. (1995) indicated that such tools have been developed in an ad hoc fashion without the use of statistical regression models to choose and weigh the factors that may predict development. As such, their validity remains problematic. Morison (2001) argues that incontinence or moisture may not be a primary factor but rather an indicator of poor physical condition, stating that it has not been identified by prospective cohort studies, which identify key diagnostic factors using multivariate statistics. However, there are indications of the importance of moisture in pressure ulcer risk from some studies (Haalboom et al., 1999). This study revealed that the incontinence factor increased the incidence of pressure ulcers by a factor of 6.2 (Odds Ratio), although the wide 95% confidence interval (2.3–17) revealed the low precision of the point estimate.

The EPUAP (1998) identified incontinence and ‘moistness’ as key pressure ulcer risk factor and therefore as clinical issues to be managed. Halfens et al. (2000) examined the evidence to support the established Braden scale (Bergstrom et al., 1987a, b); analysis revealed that only age and incontinence of urine and/or faeces were related to the external criteria for risk of pressure sore (including non-blanchable oedema and skin loss).

Preventing and minimising iatrogenic effects
Health professionals may adversely disrupt the skin barrier in a range of ways; these may include through poor washing practices, the impact of ADRs on the skin and a lack of adequate pressure- relieving interventions. As washing practice and pressure ulcer prevention are discussed elsewhere, here we will focus on the adverse effects of drugs on the skin and their prevention.