A study of the prevention and management of pressure sores

A study of the prevention and management of pressure sores Elizabeth P. Tolmie and Lorraine N. Smith

Objectives: (1) To determine if there was an association between pressure sore risk assessment, severity of sore and planning of patient care and (2) to identify the methods used to prevent and treat pressure sores. Design: The study was a two-phase non-experimental design. Methods: All patients had pressure sore risk assessed on admission and discharge. They were scored according to the Waterlow system or the Stirling Pressure Sore Severity Scale. Nominal data were analysed by v2 and grouped data by Kruskal–Wallis ANOVAR. Setting: 500 bedded acute care hospital trust in Scotland. Sample: 30 Registered Nurses and 327 patient records. Results: Significant relationships were detected: 1. Between the Waterlow score and pressure relief (v2 = 32.92, df = 2, p < 0.001) between the Waterlow score and patient education (v2 = 6.04, df = 2, p < 0.05). 2. Between care plan type and pressure relief (v2 = 38.3, df = 2, p < 0.01) mobilisation (v2 = 12.1, df = 2, p < 0.016) and patient education (v2 = 40.8, df = 2, p < 0.01).

There was no significant relationship between Waterlow score and mobilisation (v2 = 3.2, df = 4, p = 0.530) or between Waterlow score and severity of sore (df = 4, p = 0.7265). Conclusion: The initial Waterlow score was not predictive although the Stirling Pressure Sore Severity Scale was indicative of skin status. This study indicates that a number of issues need to be addressed. Of particular concern is that even when risk factors were identified for a patient, they were rarely taken into account when planning care. Furthermore, according to nurses’ own accounts and by patient record analysis, the Waterlow Risk Assessment Scale appears to be unreliable when used in clinical practice. c 2003 Elsevier Science Ltd. All rights reserved.


Elizabeth P. Tolmie MSc BA DipN(Lond) Research Assistant, Nursing and Midwifery School, University of Glasgow, 59 Oakfield Avenue, Glasgow G12 8LW, UK

Keywords: pressure sores, risk assessment, risk score, Waterlow

Lorraine N. Smith PhD, MEd, BScN Professor of Nursing, Nursing and Midwifery School, University of Glasgow, 59 Oakfield Avenue, Glasgow G12 8LW, UK

Recent pressure sore guidelines (NMPDU 2002; RCN 2000) make it clear that when an individual is identified to be at risk of developing a pressure sore(s), it is the duty of the health care professional to ensure preventative measures are implemented. However, the uncertainty regarding pressure sore risk assessment scales, as evidenced by the absence of any firm guidelines on their use, has resulted in the recommendation that pressure sore risk

Correspondence to: Elizabeth P. Tolmie, Tel.: +44-141-330-5645; Fax: +44-141-330-3539; E-mail: E.P.Tolmie@clinmed. gla.ac.uk

INTRODUCTION

Clinical Effectiveness in Nursing (2002) 6, 111–120 doi:10.1016/S1361-9004(02)00071-7

C

2003 Elsevier Science Ltd. All rights reserved.

assessment scales be used in conjunction with clinical judgement (NMPDU 2002; AHCPR 1992; EPUAP 1998; RCN 2000), a statement open to interpretation. Some researchers have found clinical judgement alone to be a reliable method of identifying those at risk of pressure sores (Preevost 1992; Salvadena et al. 1992; Hergenroeder et al. 1992; Young 1996) while others (Norton et al. 1962; Waterlow 1995) consider that professional judgement is subjective and that the use of a formal risk assessment tool

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provides an objective measure of risk status (Norton et al. 1962). Nevertheless, few studies have investigated how risk assessment scales are used in practice or whether management of care is based on the risk factors identified at assessment. Jones (1986) demonstrated that nurses, when using a logically structured database such as a pressure sore risk assessment scale, gave more specific, detailed and individualised prescriptions for care than those using an intuitive approach. However, results indicated that nursing care was highly routinised and that the intuitive approach resulted in patients receiving a blanket approach to care (Jones 1986). Furthermore, Salvadena et al. (1992) found that even when patients were identified to be at risk of pressure sores, preventative strategies were rarely implemented. The Waterlow Risk Assessment Scale, the most widely used risk assessment scale in the UK (Waterlow 1991; Wardman 1991; Cook et al. 1999), incorporates 11 main assessment criteria (build/weight for height, continence, visual skin type, mobility, sex/age, appetite, tissue malnutrition, neurological deficit, major surgery/trauma and medication). The criteria sex and age have been combined, essentially leaving only 10 criteria. Each criterion has a number of sub-scales rated on a scale of 0–8 according to degree of risk. A zero rating is allocated to any sub-scale which indicates Ôno riskÕ. A patientÕs risk score is calculated by adding the relevant number from each sub-scale. The degree of risk is then classified into one of three risk categories based on the total score obtained: 10–14 (Ôat riskÕ); 15–19 (Ôhigh riskÕ); 20+ (Ôvery high riskÕ) (Waterlow 1985). The utility of a risk assessment scale is evaluated in terms of its sensitivity and specificity (National Pressure Ulcer Advisory Panel 1989; Bergstrom 1992). The reported sensitivity and specificity of the Waterlow Risk Assessment Scale has varied across studies (Chan et al. 1997; Pang and Wong 1998). This is not surprising when one considers the extraneous variables likely to affect the reliability and validity of the scale. However, it is unclear as to the mathematical model used by Waterlow to develop the score as the study from which the scale was developed has never been published. The sensitivity and specificity of the Waterlow scale has been shown to vary across different patient groups (Anthony and Barnes 1998; Anthony et al. 2000). Similarly, the variables within the Waterlow scale that have been found to be significant also vary across different patient groups (Anthony and Barnes 1998; Anthony et al. 2000; Boyle and Green 2001) leading to claims that many variables within the scale are confounding, weighted inappropriately (Anthony et al. 2000) or poorly discriminating (Boyle and Green 2001). Moreover Boyle and Green (2001) found the mean Waterlow score of patients developing a sore to be

21, which according to the Waterlow classification indicates Ôvery high riskÕ. Nevertheless, many health care providers have used patientsÕ Waterlow risk scores to guide the allocation of pressure reducing equipment (Waterlow 1991; Malone 1992). Pressure sore risk assessment scales are generally used in conjunction with pressure sore classification scales. The most detailed classification scale currently in use is the Stirling Pressure Sore Severity Scale which categorises pressure sores in four main stages. A fifth stage (stage 0), is applicable when no pressure sore exists. Each stage of the Stirling scale is categorised using several digits and it is recommended that at least the first two digits are recorded along with the location of the sore, its surface dimensions, severity of pain, degree of exudate and factors influencing wound healing (Reid and Morrison 1994). It has been suggested that a care plan where all information relating to pressure sores is held together might be beneficial (Waterlow 1991). However, no research has been conducted to identify whether such a care plan improves care, or encourages a more logical and systematic approach to care. In todayÕs health care culture, where the use of bank and agency staff appear to be on the increase, it is unreasonable to assume that patient care will be evaluated by the same nursing team throughout a patientÕs stay in hospital. Therefore it is imperative that the record systems used, promote continuity of care and encourage the adoption of a systematic and logical approach. The purpose of this study was to determine if there was an association between pressure sore risk assessment, severity of sore and planning of patient care; and to identify whether the use of a pressure sore care plan was advantageous.

METHOD Ethics approval Consent for the study was obtained from the hospital trust Ethics Committee including access to patient records. Written consent was obtained from all registered nurses (RNs) who participated in the study. Individual hospital consultants and nurse managers provided access. Once ethical approval was given a four-week pilot study was conducted before commencement of the main study.

Sample A purposive sample of medical records (n ¼ 327) from patients who had been admitted to and discharged from the hospital over a specified six month period was reviewed. Only records that indicated the patientÕs hospital stay was P24 h and which contained a documented Waterlow score >9, indicating the patient had been at risk of developing

A study of the prevention and management of pressure sores 113

pressure sores, were reviewed. In addition, a purposive stratified random sample of RNs (n ¼ 30) working in medical and surgical units was interviewed. To ensure respondents were routinely responsible for assessing, planning, implementing and evaluating patient care, and were familiar with the Waterlow Risk Assessment Scale, only nurses 6 grade F and working in area where the Waterlow risk assessment scale was employed, were included. Nurses working night shifts only were excluded on the basis that, at the time of the study, only staff working during day-time hours were responsible for referral of patients to other therapists and specialists and for ordering and initiating the use of specialised equipment. In addition, the researcherÕs personal experience as a nurse working within the participating hospital led her to consider that, at the time of the study, staff employed on night shifts only, planned documented and evaluated care to a much lesser extent than nurses who worked during the day.

Data collection instruments A patient record checklist and a structured interview schedule with probes were developed for the study. Face and content validity of the tools was established via ÔexpertÕ review and pilot testing. Construct validity was not established. Consensual validation of probed responses was achieved by the researcher reading back to the respondents what had been written down. Responses were transcribed verbatim and categorised according to the four stages of the nursing process (assessment, planning, implementation and evaluation).

wishing to participate and to arrange a date, place and time for the structured interview to take place. A 100% response rate was achieved. All interviews took approximately 30 min to complete and were conducted in the study site. Data collection via structured interview and patient record review was conducted simultaneously over a period of six months. The interview schedule consisted of fixed alternative questions with probes. The purpose of the probes was to elicit answers as to why the Waterlow risk assessment scale and Stirling Pressure Sore Severity Scale were perceived as they were and to determine what factors inhibited documentation if respondents affirmed that this was so. Information elicited by the interview schedule included: use and perception of the utility of the Waterlow Risk Assessment Scale and Stirling Pressure Sore Severity Scale; strategies used to prevent pressure sores in relation to patient risk score as classified by the Waterlow risk assessment scale; strategies used to treat pressure sores in relation to severity of sore as classified by the Stirling Pressure Sore Severity Scale; factors inhibiting prevention and treatment, of pressure sores; and documentation of pressure sore management. To reduce bias and to ensure that all interviewees used the same frame of reference when responding to the questions asked, the Stirling Pressure Sore Severity Scale (Reid and Morrison 1994) and the Waterlow risk levels (Waterlow 1985) were displayed for reference during the interview.

RESULTS The sample

Data collection A list of all patients admitted to and discharged from the hospital trust over a period of six months was obtained from the Hospital Statistics Department. The list was used to identify patients admitted for P24 h to a ward where the Waterlow risk assessment scale was used. Of these, the first 300 records that met the study criteria, and were available within the Medical Record Department were reviewed. A further 27 patient records identified from the hospital pressure sore database were sampled to ensure that patients with existing pressure sores were included. Patients were classified according to the three Waterlow risk categories; at risk (10–14), high risk (15–19), very high risk (20+). In addition to the record review, a letter informing potential nurse participants about the study and asking them if they wished to participate was sent to 30 RNs whose names had been drawn from a sampling frame. The sampling frame was overdrawn to replace those who were unavailable (n ¼ 4) or chose not to participate (n ¼ 3). A follow-up telephone call was made to confirm those

Of the patient records reviewed, most belonged to female patients (67%; n ¼ 218) and patients who were at least 65 years of age (n ¼ 219). More than half (58%; n ¼ 189) belonged to patients hospitalised for at least seven days. The majority of respondents from the nurse sample were grade E (n ¼ 15) or grade D (n ¼ 12). Almost half (n ¼ 14) had been qualified for at least 5 years.

Waterlow risk score and severity of sore Skin status was not documented in any way in 85 (57.4%) medical patient records and 14 (7.8%) surgical patient records. These (n ¼ 99) were excluded. Therefore 226 patient records were used in analysis. According to patient records, most patients (70%) (n ¼ 158) identified by the Waterlow Risk Assessment Scale to be at risk of pressure sores, remained pressure sore free. Of the 30% of patients (n ¼ 68) identified with a pressure sore, most (n ¼ 46) belonged to WaterlowÕs Ôvery high riskÕ

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category. A Kruskall–Wallis test was conducted to determine if there was an association between Waterlow score and severity of sore. No clear statistical association was found between Waterlow score and severity of sore (T ¼ 9:419, df ¼ 4, p ¼ 0:0514). The majority of patients had low initial scores with both systems and did not worsen. Their median Waterlow scores however were no different from those patients whose skin status did deteriorate. The Waterlow score data were split by discharge Stirling Pressure Sore Severity Scale; a Kruskal–Wallis ANOVAR produced no overall or individual significant differences (df ¼ 4, p ¼ 0:7265). We also examined the Waterlow data split by initial Stirling Pressure Sore Severity Scale score without detecting any differences (see Table 1).

Association between Waterlow risk score and planning of patient care All patient records with a documented Waterlow risk score >9 were reviewed to determine if there was an association between Waterlow risk score and planning of care. Where the Waterlow risk score changed over time, the highest score was used. Two patient records were excluded from analysis due to a data collection error. Therefore results in the following section are based on 325 patient records. The higher the patientÕs Waterlow score, the more likely they were to have prescriptions for pressure relief ðv2 ¼ 32.9, df ¼ 2, p < 0:001Þ or education ðv2 ¼ 6, df ¼ 2, p < 0:05Þ. As the Waterlow score increased, prescriptions for mobilisation also increased. However, the association between Waterlow score and prescriptions for mobilisation ðv2 ¼ 3.2, df ¼ 4, p < 0:530Þ was not significant. It is likely that some patients did not require pressure relief and others were too ill to mobilise or

receive education on pressure sore prevention. Nevertheless, further analysis of the data revealed that even when patients were identified to be at Ôvery high riskÕ, almost half (42%; n ¼ 137) did not receive either pressure relief or mobilisation or education. Although most of the patients without these preventative measures were in WaterlowÕs Ôat riskÕ category (n ¼ 75), many were identified as Ôhigh riskÕ (n ¼ 40) or Ôvery high riskÕ (n ¼ 22).

Methods used to prevent pressure sores Table 2 shows the methods (n ¼ 17) used to prevent pressure sores with the number of RNs reporting use of each method. As illustrated, most prevention measures were aimed at reducing pressure by utilising equipment, increasing patient activity or educating patients on pressure sore prevention. On comparing the prevention methods respondents said they used with the level of risk (Waterlow criteria) and severity of sore (Stirling criteria) for which respondents reported using each method, it was clear that, in general, pressure sore prevention methods were utilised regardless of Waterlow risk score. One notable exception to this was specialised beds, mattress replacements and seating systems which most respondents reported using only for patients with a Waterlow score P15 (high risk). Most respondents provided nutritional support (defined in this study as Ôassisting patients to eatÕ or Ôproviding food supplementsÕ) and utilised the services of a dietician (n ¼ 25) as a means to help prevent pressure sores developing. Two respondents reported that they did not take account of any of these methods when planning a pressure sore prevention strategy. One respondent reported rub [bing] patientsÕ heels to improve circulation. Five

Table 1 Comparison of Stirling grades at discharge or death with initial grading either by Waterlow category or Stirling grade Stirling grade at discharge/death

0 1 2 3 4

Initial Waterlow category

Initial Stirling grade

Median [interquartile range]

n

3 [2.0–4.0] 3 [2.3–4.0] 4 [3.0–4.0] 3 [2.0–4] 4 [3.0–4.0]

158 24 28 9 5

Median [interquartile range] 1 1 1 1 1

[1.0–1.0] [1.0–1.8] [1.0–4.0] [1.0–4.0] [1.0–4.0]

n 143 24 25 8 3

Kruskal–Wallis ANOVAR (df = 4, p = 0:7265).

Table 2 Methods used to prevent pressure sores and number of nurses (n = 30) reporting use of that method Equipment Specialised bed 30 Seating system 25 Foam wedge/trough l6 Heelmuff 6 Water filled gloves 5

Activity Mobilisation Position change Patient education Referral to physio Monkey pole

Nutrition 30 30 29 23 3

Nutritional support Referral to dietician

Skin care 28 25

Barrier cream Film dressing Skin observation Rubbing heels

20 2 6 1

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reported using water-filled gloves to relieve pressure at the patientÕs heel. The latter method was utilised by nurses whose comments acknowledged awareness that the method was no longer considered good practice. Twenty-three respondents reported that they documented all the pressure sore prevention methods they used. However, 10 of these did so only ÔsometimesÕ The reasons given for not always documenting preventative care were in the main related to pressure of work. For example, preventative care was not documented when there was ‘‘insufficient time’’, ‘‘interruptions and distractions’’ or ‘‘when pressure sore prevention [was] low priority’’ in relation to other demands. Deficits in documentation were also attributed by some respondents to the fact that many preventative methods were applied ÔroutinelyÕ and universally to all patients at risk. On one occasion, failure to document care was attributed to the documentation system which was considered onerous.

Methods used to treat pressure sores Treatment of pressure sores consisted of two categories; that is, methods which were also used as part of a prevention strategy; and pharmaceutical products which were applied to the skin.

As illustrated in Table 3, four products were used consistently by all respondents. These were alginate, hydrogel and cavity foam, which were applied to pressure sores P stage 3 only, and Ôdry dressingÕ, defined in this study as a gauze swab, which was applied only to pressure sores 6 stage 2. Although, in general, individual respondents restricted their use of a particular product to pressure sores of a specific stage(s), there was little consistency between respondents regarding what other products would be used in relation to severity of sore, as defined by the Stirling scale. As well as the treatments listed in Table 3, some respondents (n ¼ 22) reported ÔexposingÕ pressure sores 6 stage 2 and a few reported using scissors and a scalpel to debride more severe pressure sores (n ¼ 4). All respondents reported that they always documented all the treatment methods they used. However, a few discrepancies did exist between the products reported as used, and the products documented in patient records as used. For example, according to respondents, caustic pencil, flamazine and varidase, were used but there was no evidence of this in the records reviewed. Conversely, although all respondents said they did not use hydrogen peroxide at all, its use was documented in patient records.

Applications to the skin

Factors influencing respondents’ choice of methods

Table 3 lists the products respondents said they used (column 1) to treat pressure sores, the number of respondents using each product to treat pressure sores 6 stage 2 (column 2) and the number of respondents using each product to treat pressure sores pressure sores P stage 3 (column 3). Because some respondents used specific products for pressure sores of all stages whereas other respondents did not use some products at all, statistical tests were not appropriate. Therefore, a frequency table is used to illustrate results.

Respondents were asked to indicate by stating ÔYesÕ or ÔNoÕ which factors (Table 4) influenced the methods they chose to prevent and treat pressure sores. Because data were paired, that is, the same respondents were rating each factor, McNemarÕs test ðv2 Þ was used to determine if the proportion of respondents influenced by each factor differed significantly. Results indicated that clinical assessment and respondentsÕ own knowledge was significantly more likely to influence choice of methods than any other factor ðp < 0:001Þ.

Table 3 Products used to treat pressure sores in relation to severity of sore, as defined by the stirling pressure sore severity scale, by number of nurses reporting use of each product Application used

Barrier cream Dry dressing Iodine products Foam Hydrocolloid Alginate Hydrogel Others

a

Number of nurses using application

(all types) gauze swab film betadine iodine dressing polyurethane cavity (all types) (all types) (all types)  flamazinea  varidase/hyoxila  proflavinea  caustic pencil      

Methods proposed by respondent, not prompted by the interview schedule.

Stage 6 2

Stage 7 3

16 4 3 9 12 18 0 10 0 0 1 1 2 1

5 0 4 2 2 10 16 13 28 30 2 4 5 0

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Table 4 Factors influencing respondents choice of prevention and treatment methods by number of respondents influenced by each factor Factors influencing respondent’s choice

Clinical assessment Self knowledge Product availability Staff/cost Research Clinical guidelines Peers Tissue viability nurse Past experience Medical prescription Company information Others

Medical prescription was considered by half (n ¼ 15) of the respondents to influence their treatment decisions although the way in which it did so varied across units. For example, in dermatology where chronic skin problems were commonplace, applications to the skin were necessarily constrained by medical diagnosis whereas in other units treatment decisions were made jointly by medical and nursing personnel, by nursing personnel alone, or solely by the Consultant.

Association between care plan type and planning of patient care Two different methods of nursing documentation routinely used throughout the hospital, were compared to determine if nursing teams using a Ôpressure sore care plan managed the prevention and treatment of pressure sores more systematically than nursing teams who used a Ôstandard care planÕ method. The pressure sore care plan method differed from the Ôstandard care planÕ method in that it consisted of a Waterlow Risk Assessment Scale which incorporated a care plan proforma specifically for documenting all pressure sore related information. The Ôstandard care planÕ method contained a Waterlow Risk Assessment Scale within the nursing record. However, all other information relating to pressure sores was documented throughout the nursing notes. Due to a data collection error, the type of care plan used was not recorded on nine data collection forms. Therefore 318 patient records were available for analysis. Significant relationships were found between care plan type and pressure relief v2 ¼ 38.3, df ¼ 2, p < 0:001Þ, education v2 ¼ 40, df ¼ 2, p < 0:001Þ and mobilisation ðv2 ¼ 12.1, df ¼ 4, p ¼ 0:016). As discussed previously, it is likely that some patients did not require pressure relief and others were too ill to mobilise or benefit from preventative education. However, further analysis of the data revealed that, even when identified as being at risk of developing a pressure sore, more than half of the patients with a standard care plan (54%; n ¼ 79) and almost half of those with a pressure sore care plan which was not being utilised (45%; n ¼ 19),

Number of nurses influenced by each factor Prevention

Treatment

30 29 24 17 16 12 11 7 3 – – 1

30 30 24 15 16 13 10 9 7 15 3 4

had no prescription for pressure relief or mobilisation, or education.

Care plan type and management of identified risk factors Patient records (n ¼ 318) were reviewed to determine if there was an association between care plan type and management of build/weight for height, appetite, continence, and skin status (five Waterlow assessment criteria). Each patient record was examined to determine which of the following categories applied: 1. Problem identified and care planned to take account of that problem. 2. Problem identified but care planned inappropriately or inconsistently in relation to the problem. 3. Problem identified but no plan of care exists to take account of the problem. In four of the five assessment criteria investigated (build/weight for height, continence, and skin status) small numbers in some of the categories did not permit the use of statistical tests. Some problems were identified on the Waterlow Risk Assessment Scale but not evident in the patient care plan. When these were addressed by another member of the health care team as evidenced in co-existing documentation, they were excluded from analysis. Results are described below.

Appetite Just over half (n ¼ 167; 51%) the records reviewed identified ÔappetiteÕ on the Waterlow Risk Assessment Scale as a risk factor for the patient concerned. Of the 141 records used in analysis, more than 70% did not address the problem identified. There was no association between care plan type and management of appetite ðv2 ¼ 1.75, df ¼ 2, p ¼ 0:417). Build/weight Just over half (n ¼ 167; 51%) the records reviewed identified Ôbuild/weight for heightÕ (above or below average weight or obesity) on the Waterlow Risk

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Assessment Scale as a risk factor for the patient concerned. Of the 160 records used in analysis, only seven contained a care plan which addressed the problem.

Incontinence Ninety-two (28%) patient records identified ÔcontinenceÕ on the Waterlow Risk Assessment Scale as a risk factor for the patient concerned. Of the 75 included in the analysis, five had a care plan which appeared to be inconsistent or inappropriate. Almost half (n ¼ 36) had no associated plan of care. Visual skin type More than half (61%; n ¼ 201) of the patient records reviewed identified Ôvisual skin typeÕ as a risk factor for the patient concerned. Of the184 analysed, more than half (68%) had no associated plan of care, while three contained a care plan which appeared to be inconsistent or inappropriate.

Use and perception of the Waterlow Risk Assessment Scale All respondents (n ¼ 30) stated that they used the Waterlow risk assessment scale. More than half (n ¼ 18) found it ÔusefulÕ, while one third (n ¼ 10) found it useful to some extent. Two respondents did not find the scale useful at all. Probed responses regarding respondentsÕ perception of the utility of the Waterlow Risk Assessment Scale were analysed using a content analysis procedure. Responses were classified into four categories: assessment, planning, implementation, and evaluation as defined by the nursing process.

Assessment RespondentsÕ perception of the usefulness of the Waterlow risk assessment scale was varied. Three respondents thought the scale acted as a prompt for assessment. Eight felt that it identified patients who were at risk of pressure sores but did not appear to be so and ‘‘might otherwise have been missed’’. However, six respondents considered the Waterlow Risk Assessment Scale to be subjective and therefore of limited use. The assigned score was said to be nursedependent resulting in the patientÕs physical condition being scored inaccurately at times. In addition, seven respondents considered their own professional judgement to be a more accurate method of determining patient risk. This was evidenced by remarks such as Ôit is a false readingÕ, or ‘‘it is deceiving’’. and respondentsÕ comments that they could ‘‘tell if the patient [was] at risk by looking at them’’. Planning care In the main, few respondents appeared to use the Waterlow risk assessment scale to plan patient care. Although one reported that the Waterlow score

helped her determine how often pressure area care was required, most referred to the way in which the Waterlow scale improved record keeping by ‘‘improve[ing] documentation’’ and making ‘‘others aware that pressure area care was part and parcel of patient care’’.

Implementing care Using the Waterlow Risk Assessment Scale was not always considered to be an effective way of ensuring appropriate care. This was evidenced by the comments of one respondent who reported that patients identified to be at risk of developing pressure sore(s) were in danger of being overlooked because the assessing nurse would not necessarily be caring for the patient. However, all respondents saw the Waterlow scale as a way of helping them to acquire the use of a special bed. Most believed that a high risk score was necessary to justify the use of specialised equipment with six reporting that the Waterlow scale was used solely for this purpose. Comments such as, ‘‘if the score is high you can get a bed before the skin breaks’’, ‘‘a high score helps back the need for a bed’’ and ‘‘over 20 will justify a bed’’ reinforce this point. In some instances the relationship between Waterlow score and resource allocation seemed to be linked to the philosophy of the ward or that of the nurse-incharge. For example, one respondent reported that s(he) often altered the score to procure a special bed if s(he) felt the patient was not scoring sufficiently high to justify one, while another reported that staff were sometimes instructed to ‘‘mark down’’ the score to reduce the number of special beds requested. Evaluating care In general, the Waterlow Risk Assessment Scale was not perceived by respondents as a useful tool for monitoring changes in the patientÕs condition. Three made reference to the Waterlow scale in relation to care evaluation in that it helped them ‘‘keep a check’’ on things and provided ‘‘an update’’ of the patientÕs progress.

Use and perception of the Stirling Pressure Sore Severity Scale (SPSSS) Most respondents (n ¼ 29) used the Stirling pressure sore severity scale (Reid and Morrison 1994) to classify pressure sores and most (n ¼ 26) found it useful to varying extent. Four respondents did not find the Stirling Pressure Sore Severity Scale at all useful. Probed responses regarding respondentsÕ perception of the utility of the scale were analysed using content analysis and classified into the four categories defined by the nursing process.

Assessment Many respondents thought the Stirling classification system helped convey the severity of the sore,

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without the need to expose the wound unnecessarily. Respondents saw this as particularly useful when they returned to work following days off. For example, it was considered ‘‘good at handovers’’ and useful as a ‘‘standard measure’’ because it encouraged everyone to speak ‘‘the same language’’. However, six respondents did not think the scale enabled them to classify pressure sore(s) appropriately with others reporting they were ‘‘forced to grade higher or lower than [they] wish [ed]’’.

Planning care Only two respondents made comments which suggested that they perceived the Stirling Pressure Sore Severity Scale as useful when planning care. One referred specifically to the usefulness of a poster depicting the Stirling criteria and associated skin status displayed on the ward. Another stated that the Stirling scale helped her/him see the intervention required ‘‘even before the patient [is] seen’’. Implementing care The perceived benefit of the Stirling classification system appeared to be linked to the legal and professional issues associated with documentation of patient care rather than care provision. For example, a few respondents (n ¼ 4) seemed to value the way in which the scale could be used to ÔproveÕ that the sore had not developed as a consequence of poor nursing care within their own unit. This was evidenced by comments such as ‘‘it is good when the patient [is admitted] with a sore’’; ‘‘it covers you’’; and ‘‘it is good for documentation purposes only’’. Evaluation While the accounts of five respondents suggested that they used the Stirling Pressure Sore Severity Scale to monitor the progress of pressure sores, comments such as ‘‘it shows where it has got worse’’; ‘‘you can assess if it has got worse or better’’; ‘‘it is an indicator of improvement or deterioration’’ indicate that reverse staging was not uncommon.

SUMMARY The respondents participating in this study were employed across a wide range of medical and surgical departments across the Trust. Almost half had been qualified for more than five years. In their capacity as ward-based nurses employed on day duty or on a rotational shift basis, all were responsible for the prevention and management of pressure sores. In addition, a purposive sample (n ¼ 327) of patient records which represented admissions to, and discharges from, medical and surgical units throughout the hospital was reviewed.

As such, the sample was representative of patients cared for within an acute hospital and of the care planning systems in use throughout the hospital. All contained a documented Waterlow score >9 which indicated that the patient concerned was at risk of pressure sores.

DISCUSSION Norton (1989) and Waterlow (1996) believe that the occurrence of pressure sores might be prevented if the obtained risk score prompts preventative measures and that in such circumstances, the Waterlow risk assessment scale may appear to have poorer sensitivity/specificity (Waterlow 1996). The ethical issues associated with this theory prevent it from being tested as patients identified to be at risk could never be denied care which would reduce this risk. The results of this study showed that patients with a higher Waterlow score, were significantly more likely to have prescriptions for pressure relief and education. Nevertheless, it was clear that nurses influenced the overall risk score allocated to patients. On some occasions, the obtained score was falsely increased to justify the use of specialised equipment while at other times the score was reduced to justify the non-use of such equipment. As such, Waterlow scores were subject to bias due to manipulation and subjectivity; a factor which might explain some of the variation in the scaleÕs reported sensitivity/specificity. It does, however, suggest that nurses rely on their own assessment method when determining patient risk. Therefore, it seems reasonable to conclude that management of care is influenced by factors other than risk score alone and that nurses influence not only resource allocation but also the association between Waterlow risk score and management of care. Results of this study support WaterlowÕs view (1991) that a care plan, where all pressure sore information is held together, may be beneficial. However, in this study, risk factors, specific to the individual, were rarely planned for even when identified on the Waterlow Risk Assessment Scale. Thus the benefits of a pressure sore care plan may not extend beyond blanket prevention strategies such as ÔmobilisationÕ, Ôpressure reliefÕ and ÔeducationÕ; factors which could be applied almost universally to all patients at risk. Further research would be required to determine why this is so. However, during the conduct of this study it was clear that risk score was often documented without individual risk criteria being identified. Consequently, it was not always possible to determine which problem(s) contributed to the overall risk score. In such circumstances specific care needs cannot be identified, and hence met, solely on the basis of a Waterlow risk assessment. Consequently, although it has been suggested that the Waterlow

A study of the prevention and management of pressure sores 119

Risk Assessment Scale be used as an aide memoir rather than to predict pressure sores, it is not clear how the Waterlow risk assessment scale would be more useful in this respect than a more general assessment tool such as the Activities of Daily Living. The methods used by respondents to prevent and treat pressure sores were numerous and, according to respondents, more likely to be influenced by clinical assessment and respondentsÕ own knowledge than any other factor. Most of the methods used to prevent pressure sores were as recommended by the guidelines (AHCPR 1992; CRAG 1995) available at the time of the study. Nevertheless, some of the methods used were specifically contra-indicated (heel rubbing) or considered detrimental (water filled gloves). What is worrying is that users who were aware the latter method was considered poor practice employed the method. The products used to treat pressure sores were also, in general, as recommended in the literature available at the time of the study (SMTL 1993; Thomas 1994; SMTL 1995; Bux and Malhi 1996; SMTL 1997). However, there was little consistency between respondents regarding what treatments were used in relation to severity of sore. Furthermore, the review of patient records suggested that a number of different products were applied to the same pressure sore(s) over a short period of time even when there was no documented evidence that the sore had improved or deteriorated. While initial responses regarding the utility of the Waterlow risk assessment scale and Stirling Pressure Sore Severity Scale were, in the main, positive, probes revealed respondentsÕ believed both scales to be subjective and hence of limited applicability in clinical practice. RespondentsÕ accounts of the way in which they utilised the Waterlow Risk Assessment Scale and Stirling Pressure Sore Severity Scale raise some interesting questions concerning the reliability and validity of the instruments.

CONCLUSION As shown in this study, patient care plans are inadequate and provide little evidence that patient problems are being identified and appropriately planned for. These results, which support those of many earlier studies, suggest that the systems currently in place to record and evaluate patient care are at present, inadequate. In this study, use of the care plan relating specifically to prevention and management of pressure sores did not improve the situation to any great extent. Therefore it is clear that new systems for recording patient care need to be developed and evaluated. Considering that problems associated with inadequate documentation are long standing, it is a matter of some urgency that appropriate alternatives are found.

Despite the plethora of literature relating to pressure sores, the results of this study indicate that further investigation in a number of areas is required. Inconsistencies in treatment, over-reliance on classification score to determine skin status, and reverse staging are problems which need to be addressed as they are likely to result in inappropriate treatment. Moreover, further research is required to determine why nurses knowingly use methods considered to be ineffective. Finally, results of this study indicate that when used in routine practice the Waterlow Risk Assessment Scale is unreliable. As the scale is the most widely used pressure sore risk assessment tool in the UK, the costs associated with its maintenance may well outweigh the dubious benefits of its continued use.

STUDY LIMITATIONS The main limitations of this study were that no observation of actual practice was conducted and the view taken that what was not documented was not done. In addition, the sample was obtained from a single hospital site using data collection instruments developed for the study. These limitations were minimised by using two different data collection methods and by establishing face and content validity of the data collection instruments via expert review and pre-testing.

ACKNOWLEDGMENTS We would like to thank Mr Philip Belcher, Glasgow Royal Infirmary, North Glasgow University Hospitals, and Dr Grace Lindsay, Glasgow University, Nursing and Midwifery School, for their advice and assistance. The study was supported by an educational grant from The Hospitals Savings Association, and the hospital in which the study took place.

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