Pressure sores: a diseasewithout definition

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REPORT

Pressure sores: a disease without definition E. M. Hillan and A. K. Fraser As a largely preventable condition, pressure sores hold potential for clinical audit and monitoring of the quality of care and offer an indicator of effective clinical m a n a g e m e n t across disciplines.The D e p a r t m e n t of Health view pressure sores as a key quality indicator ( D o l l 1993) and have published a guide on the topic for N H S purchasers and providers. However, the condition lacks an agreed definition and grading scale. Most scales in widespread use are anomalous and include lesions which are not generally regarded as pressure sores.These scales have been used as a proxy for a proper definition. Before the pressure sore becomes a key quality indicator in clinical audit across the N H S , there needs to be an agreed definition and accepted classification scale.Without a consistent, systematic and valid approach, pressure sore surveys, audits and quality will have little meaning.

D r A n d r e w K. Fraser biB, ChB, MPH, I~IFPHN, Director of Public Health, Highland Health Board, Beechwood Park, Inverness IV2 3HG, UK D r Edith M. Hillan, PhD, HSc, biPhil, Dip LSc, RGN, RSCN, RM, Senior Lecturer; Nursing & Hidwifery Studies, University of Glasgow, Glasgow G 12 8QQ, UK.

Pressure sores remain a constant feature in an everchanging health service. A recent article documented the descriptions of the condition by Sir James Paget in his patients in the mid 19th century (Bliss 1992). He recognized that pressure sores were an important complication particularly in the sick, the elderly and following surgery. Today, pressure sores continue to affect a substantial proportion of the patient population (Petersen & Bittman 1971, David et al 1983, Hillan et al 1992). In recent times they have been the subject of attention in the Health of the Nation discussion paper (Doll 1991) and a National Audit Office report (National Audit Office 1992). As a largely preventable condition, pressure sores hold potential for clinical audit and monitoring of the quality of care and offer an indicator of effective clinical management across disciplines. The Department of Health view pressure sores as a key quality indicator (Doll 1993) and have published a guide on the topic for NHS purchasers and providers. Perhaps one of the greatest obstacles to research and audit in this area is that the condition lacks an agreed definition and grading scale. In order to make meaningful comparisons of prevalence and incidence data, it is essential that a uniform classification system is agreed so that comparisons can be made between studies. Most scales in widespread use are anomalous and include lesions which are not generally regarded as pressure sores. Classification of sores is even more problematic and at least 16

Clinical Effectiveness in Nursing (1998) 2, 103 1059 1998HarcourtBrace& Co. Ltd

different classification scales have been published and further variations of these are in local use (Healey 1996). These scales have been used as a proxy for a proper definition. Without a consistent, systematic and valid approach, pressure sore surveys, audits and quality will have little meaning. Studies of pressure sores adopt three main approaches to case definition: 9 9

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they state their own definition (Petersen & Bittman 1971, Allman et al 1986, Dealey 1991) they use a pressure sore grading classification to provide a guide (David et al 1983, Nyquist & Hawthorn 1987, Hillan et al 1992) there is no attempt at definition (Verluysen 1986, Gosnell & Pontius 1988).

This makes comparison of studies difficult. In one of the first large prevalence studies conducted in Denmark, Peterson & Bittman (1971) stated the inclusion criteria used: at least an epithelial defect was present. The occurrence of erythema, oedema or vesiculation was not included. Although this was one of the first large prevalence studies of pressure sores, widely referenced by subsequent authors, the definition was not adopted. Smaller more recent studies in the UK have used a different approach and prefer to include unbroken skin. For instance: damage to the skin caused by pressure, shear or friction or a combination of any of these. (Dealey 1991)

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This definition identifies three important components associated with pressure sore formation in experimental studies; however, it does not satisfactorily exclude sores or lesions caused by acute trauma or peripheral vascular disease, both venous and arterial. As a result various ulcers or even scratches might be included. The two most recent definitions originate from the USA and UK. The former is contained in a consensus statement for the US Agency for Health Care Policy and Research (1992) which defines a pressure sore as: .,,any lesion caused by unrelieved pressure resulting in damage of underlying tissue. While this is brief and elegant, the definition is vague about the time component of pressure and the need for that pressure to originate from outside the body (excluding intravascular influence). The second definition contained in the Department of Health document Pressure sores: a key quality indicator (1993) is also rather vague and includes both pathological and physiological effects: ...a new or established area of skin and/or tissue discoloration or damage which persists after the removal of pressure and which is likely to be due to the effect of pressure on the tissues. In clinical practice pressure sores may be even more difficult to define. In our survey of auxiliary nurses' knowledge of pressure sores, 86% (99/115) responded in terms of a break or mark in the skin to the open question 'what is a pressure sore?' Marked skin requires vigilance and preventive management and broken areas signify the need for active treatment. However, there is uncertainty in the published literature as to whether marks and breaks should be included within the definition of a pressure sore (Petersen & Bittmann 1971, Allman et al 1986, Dealey 1991).

CLASSIFICATION OR GRADING SCALES The use of grading scales provides variation on a similar theme. There are three dimensions: 1. The nature of the wound bed - this may be described in clinicopathological terms, it varies with time and is not widely used. 2. Cross sectional area - the breadth and margins of pressure sores have been the subject of the largest body of structured discussion and validation of suitable techniques. They have not seen widespread application. 3. Depth or involvement of skin layers. There are several scales, usually including four or five grades. The first is often an abrasion or similar lesion; the second includes blistering and superficial skin loss; three, four and five are

deeper lesionS with the most severe involving cavities. Both British and American scales derive from gradings of burns. In the USA there has been a degree of unanimity where the Shea classification has been used for 16 years. However, in the largest detailed institutional prevalence study so far published, Brandeis et al (1990) chose to adopt their own classification. In the UK a variety of scales exist. Most popular is the Jordan and Clark classification (1976) and it has attracted a number of variants. More recently there have been further classifications proposed by Torrance (1983), David et al (1983) and Reid and Morison (1994). A recent survey showed that none of these tools demonstrated great reliability especially with less severe grades of sore (Healey 1995) and the most complicated grading system (Reid & Morison 1994) was the least reliable in terms of nurses reporting accurately. Confusion arises when surveys vary in their use of grading to define cases. Some surveys use all grades (David et al 1983, Dealey 1991), while others omit minor grade 1 lesions (Nyquist & Hawthorn 1987). A number of authors cite variability in the reporting of the more minor lesions (David et al 1983) and it might be expected that these would be the most common. In fact, most surveys reporting sores by all grades of severity show peak prevalence at grade 2. In one major study of all hospital patients in three English regions, commissioned by the DHSS, the peak incidence of pressure sores was grade 3 (David et al 1983). The Jordan and Clark classification system was used and all reports were validated. Under-reporting of grade 1 sores was found to be 69%, and of more severe lesions, it was 12%. If this under-reporting applied in other situations then the widely quoted prevalence of pressure sores in hospital would rise from 6.7% to 9.2% for all grades and to 5.7% (95% C.I. 5.3%-6.0%) for sores graded 2 or worse. Before the pressure sore becomes a key quality indicator in clinical audit across the NHS, there needs to be an agreed definition and accepted classification scale. From a pragmatic stand we therefore support the definition used by the US Agency for Health Care Policy and Research which was subsequently adopted in other UK policy documents: ...any lesion caused by unrelieved pressure resulting in damage of underlying tissue. A classification system should exclude, or relegate to grade 0, any lesions which fall outwith this definition. The system proposed by the US Agency for Health Care Policy and Research (1992) has been published subsequently (with minor modifications) in both the Department of Health (1993) and the Scottish Office Department of Health documents (1995). As these documents have been extensively circulated, it seems reasonable to suggest that this classification should be adopted throughout the

Pressure sores: a disease without definition UK. This would allow comparisons

to b e m a d e

across Health Boards / Authorities. We remain concerned that many lesions which are not the result of p r e s s u r e d a m a g e m a y b e c l a s s i f i e d as S t a g e 1 p r e s s u r e s o r e s u s i n g this c l a s s i f i c a t i o n a n d w o u l d t h e r e f o r e treat t h e s e w i t h c a u t i o n . H o w e v e r , i f p r e s s u r e s o r e s are s e e n as a k e y q u a l i t y i n d i c a t o r it is e s s e n tial that t h e a u d i t a n d r e s e a r c h c o m m u n i t y h a v e a c o m m o n l a n g u a g e w i t h w h i c h to c o m p a r e like w i t h like. F r o m a p r a g m a t i c s t a n d w e t h e r e f o r e s u p p o r t t h e u s e o f this c l a s s i f i c a t i o n .

ACKNOWLEDGEMENTS

The authors acknowledge the support of the Clinical Resource and Audit Group of the Scottish Office Home and Health Department who funded the Scottish Audit Study for Pressure Area Care (SASPAC), Mrs Marian McGhee and staff of Inverclyde Royal Hospital for survey data. The views expressed in this article are those of the authors.

REFERENCES

Agency for Health Care Policy and Research 1992 Clinical practice guidelines on pressure ulcers in adults: prediction and prevention. AHCPR, USA Allman RM, Laprade CA, Noel LB et al 1986 Pressure sores among hospitalized patients. Annals of Internal Medicine 105:337 342 Bliss MR 1992 Acute pressure area care. Sir James Paget's legacy. Lancet 339:221-223 Brandeis GH, Morris JN, Nash D J, Lipsitz LA 199(/The epidemiology and natural history of pressure ulcers in elderly nursing home residents. 264(22): 1905-1909 David JA, Chapman RG, Chapman E J, Lockett B 1983 An investigation of the current mcthods used in nursing for

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the care of patients with established pressure sores. Nursing Practice Research Unit, Middlesex Dealey C 1991 The size of the pressure sore problem in a teaching hospital. Journal of Advanced Nursing 16 (6): 663-70 Doll 1991 The Health of the Nation (Green Paper). Annex N: Rehabilitation services for people with a disability HMSO, London, pp: 96-8 Doll 1993 Pressure sores a key quality indicator: a guide for NHS purchasers and providers. HMSO, London Gosnell D J, Pontius C 1988 A model of quality assurance for decubitus ulcer monitoring. Decubitus 1(4): 24-9 Healey F 1995 The reliability and utility of pressure sore grading scales. Journal of Tissue Viability 5 (4): 111-114 Healey F 1996 Classification of pressure sores. British Journal of Nursing 5(9): 567-574 Hillan EM, Fraser AK, Robertson W M A 1992 The prevention and management of pressure sores: a multidisciplinary approach to audit. Scottish Office Home and Health Department Clinical Resource and Audit Group, Occasional Paper no. 5 : 1 - 9 Jordan MM, Clark MO 1977 Report on incidence of pressure sores in the patient community of the Greater Glasgow Health Board area on 21, January 1976. University of Strathclyde, Glasgow National Audit Office 1992 Health Services for Physically Disabled People aged 16 to 64. HMSO, London, pp 4 20 Nyquist R, Hawthorn PJ 1987 The prevalence of pressure sores within an area health authority. Journal of Advanced Nursing 12:183 187 Petersen NC, Bittmann S 1971 The epidemiology of pressure sores. Scandinavian Journal of Plastic and Reconstructive Surgery 5:62-66 Reid J, Morison M 1994 Towards a consensus: classification of pressure sores. Journal of Wound Care 3(3): 157-160 Torrance C L983 Pressure sorcs: aetiology, treatment and prevention. Croom Hehn, London Versluysen M 1986 How elderly patienls with femoral fiacturc develop pressure sores in hospital. British Medical Journal 292:1311 1313