The Assessment of the Skin of the Elderly Patient with Specific Reference to Decubitus Ulcers and Incontinence Dermatitis

85 Journal of Tissue Viability 1993 Vol. 3 No 3

THE ASSESSMENT OF THE SKIN OF THE ELDERLY PATIENT WITH SPECIFIC REFERENCE TO DECUBITUS ULCERS AND INCONTINENCE DERMATITIS DENIS ANTHONY Computing Services, University of Warwick, Coventry INTRODUCTION This paper will discuss the assessment of skin of the elderly incontinent patient. It will concentrate on two areas, decubitus ulcers and incontinence dermatitis; the latter because it is a direct result of incontinence, and very common, and the former because it is associated with incontinence and old age, and is a serious condition that may be life-threatening; and is a costly condition to treat. The Ageing Human Skin As the human ages, the skin undergoes several changes, many of which make it more susceptible to disease or damage. These include:-

•

Micro-circulation, reduction of vascularisation, 1 and blood flow 2 Thinning of epidermis 1• 3 Reduced elasticity 2 Hydration, loss of stratum corneum water content, transepidermal water transfer 2 Morphological changes (increased roughness, reduced pigmentation) 2•4 Increase in complexity of cutaneous micro-relief 5 Reduction in hydrolipid emulsion 6

The changes affect the ability of the skin to maintain its functions of protection, absorption, thermoregulation, sensory perception etc 7 • Of particular relevance to incontinence is the reduced capability of the skin to act as a barrier 8 , and the potential need therefore for some artificial barrier, such as a cream, to be provided in the event of an attack on the skin. The reduced blood flow of the skin makes ulceration more likely to occur, and healing more slow. It is likely the reduced elasticity will allow greater damage to the skin. The Bacteriology of Elderly Skin The normal skin is not sterile, it contains micro-organisms that are well suited to the harsh climate of the skin. Not only do such organisms face a dry, acidic environment, but the skin is constantly desquamating. Normal skin flora contains staphylcocci, diptheroids and a small number of other species 9• Normally the skin flora is not pathogenic, though if the numbers of organisms are allowed to increase in wet environments, some clinical infection may occur, especially in debilitated individuals. Studies of premature babies have shown infections under occlusive tapes 9•

The skin of elderly incontinent patients show similar patterns to the young, and the ischial tuberosities contains, typically, densities of 104 , with unremarkable flora 9•10 • Bacterial contamination may occur in decubitus ulcers, but this is much more common in sores that contain slough than debrided sores. Decubitus ulcers may be heavily colonised with staphylococci, but this is not thought to delay healing 11 • Streptococci have been found in ulcers, and in animal experiments ulcers were able to be produced by the introduction of a streptococci infection 12• Candida albicans has been found in ulcers, and conflicting statements have been made concerning healing after treating and removing the yeast 13 • The flora of most ulcers is typically different than that of the skin, through there is disagreement over the clinical significance of much of the microbial inhabitants of ulcers. It seems probable that certain organisms are harmful, and may include beta haemolytic streptococci. It is also likely that healing is adversely affected by bacterial contamination above lOS/gram of tissue 14 • Incontinence Dermatitis Where incontinence pads are used in the treatment of (typically elderly) patients they may develop incontinence dermatitis (nappy rash). The assessment of the presence and severity of inflammation of the skin is necessary in determining the optimal treatment and prophylaxis measures. The skin of the incontinent patient is subject to damage due to dampness, and the irritant effect of the constituents of urine. Furthermore it is the nature of the population of incontinent patients that they are typically debilitated. The elderly are particularly prone to skin breakdown, where immobility, incontinence, intercurrent physical illness and dementia may co-exist. The micro-climate of the skin is, in the normal human, a difficult place for organisms to flourish. It contains little water, has a pH of about 5.6, with high salt levels 9• The addition of water allows microbial flora to flourish and make the skin more alkaline 9• The presence of urine on the skin will also make the skin more alkaline, and even after washing the urine off, the skin may remain neutral rather than acidic. The cause of incontinence dermatitis is usually rather sketchily ascribed to the effects of the urine, without analysing the precise pathology. It is clear that urine changes the microclimate of the skin, making it more moist, and less acidic. A different flora may then inhabit the area, but it is not necessarily clear that the altered flora is the cause of an erythematous

Journal of Tissue Viability 1993 Vol. 3 No 3 86 reaction. The conditions for some skin reactions are quite complex, and may require more than one condition to prevail, e.g. heat rashes u· 16 • It has been suggested that incontinence dermatitis may sometimes be a manifestation of miliaria rubra u, a condition seen in some individuals in the tropics. The pathogenesis of this condition is complex. It has been postulated, based on empirical evidence, that maceration of the skin by copious sweating caused blockage of the sweat duct by 'horny plugs'; but the condition only occurred in certain pre-disposed individuals 15 • Later workers failed to find plugs in individuals with the condition, but found PAS-positive material in the sweat duct. The hypothesis was that there was an increased bacterial density occasioned by excessive sweating, and a toxin secreted by the bacteria caused the mass. This is given some credence as subjects treated with anti-bacterials did not develop the condition 16 • If the incontinence dermatitis of infants is of similar pathology

as that of the elderly (which is not obvious, as the aged skin is very different from an infant's) then one may use the know ledge gained on 'nappy rash'. This condition has been thought to result from C. albicans and/or S. aureus, possibly in combination, though this has also been disputed 17• Similarly ammonia has been cited as a culprit, and also discounted, though ammonia may have more of a role on damaged skin 17 • Pressures Sores Pressure sores (decubitus ulcers) are common in the elderly, and the factors conducive to their formation overlap with the features associated with urinary incontinence, ie. dementia, general debility, and incontinence itself is a predisposing factor in sore formation 18 • Recent judgments in the USA19 indicate that fuller and more accurate records of decubitus ulcers will be needed, this may well include the grade and size of the sore, and the general condition of the at-risk patient . METHODS OF ASSESSMENT When assessing a patient one should try to predict the likelihood of development of a condition, so as to be better able to prevent it arising, and be better prepared to treat it should it occur. In the event of a condition being present one needs assessment of severity, and of response to treatment. It is argued in this paper that theassessmentmethods for prediction have been developed, and that the high risk candidates for both incontinence dermatitis and especially decubitus ulcers are well known. A review of these important and useful assessment techniques follows.

earliest being the Norton score 20 • Mobility of patients is a major factor, as shown in early studies by Exton-Smith and verified by later workers such as Barbenel et al 21 • As the length of time a patient is immobile is relevant, one should note the times a patient is immobilised prior to admission, in casualty, in the operating theatre etc. While these times may not be always available, they should be recorded when they are as it has been shown that most elderly patients22 admitted with fractured femur(e.g.) have been subject to periods of immobility in excess of that known to be associated with decubitus ulcer formation prior to entering the ward. Medication, both systemic (e.g. steroids predispose to sore formation) and local (many applications used on wounds cause tissue damage, in particular EUSOL and other hypochlorites) affects wound healing. Therefore in assessing skin breakdown the prescribing of medication should be reviewed. Pressure Decubitus ulcers are often referred to as pressure sores, which is misleading as pressure per se is not the root cause of the formation of sores 23 • The term is so wide-spread however that it is used in this paper as a synonym for decubitus ulcer. In fact it is the deformation of tissue that pressure occasions that cuts the circulation to tissues and causes sores. If pressure is applied equally in all directions (as in a water bed) there is no danger of sore formation. Applied pressure that is not balanced produces a shear force and disruption of the blood supply; measurements of blood flow are correlated with applied pressure under these circumstances, as the pressure increases, the blood flow (locally) decreases 24 • With this caveat in mind it is instructive to measure the pressures exerted on tissue by various mattresses and pressure relieving devices.

Pressure has been measured to evaluate the effects of under and over-inflation of air-filled cushions 25 , thoracic suspension 26, different mattresses 27• 28• 29• 30• 31 • 32• the seating position in wheelchairs 33, the shape of foam cushions 34 , to compare different cushions 35 •36• the benefits of electrical stimulation (it reduced interface pressure 37 , the suitability of heel supports 38 ,the effect of lumbar support in spinal cord injury (SCI) wheelchair patients (it was negligible) 39 , and the difference between children and adults with respect to pressure loads 40 •

Once incontinence dermatitis or decubitus ulcers are present there is, in contradistinction to prediction parameters, a paucity of assessment techniques. Thus while treating patients one finds it difficult to establish the optimal regimes, as there is little in the way of objective, sensitive and accurate data to analyse. A later section of this article will explore some preliminary work on assessment of the progress of incontinence dermatitis and decubitus ulcers.

Pressuremaybecontinuallymeasuredanddatastoredonamicrocomputer 41 •42 • to investigate the effects of seating position etc. on pressure. Such information has been used to warn wheelchair patients of the need to lift the ischial area 43 • Such continuous monitoring has been used to determine the levels of pressure that quadriplegics may withstand 44 ( which in many cases is higher than the levels found acceptable for elderly patients). Measurements of interface pressure of subjects on a mattre.!!S have been shown to be correlated with an index calculated, based on laboratory measurements of foam overlays 45•

ASSESSMENTOFRISKOFDEVELOPINGDECUBITUS ULCERS Scoring Systems and General Assessment Over the years various scoring scales have been implemented to evaluate the risk of decubitus ulcers forming, one of the

The relative risks of pressure to different areas has been explored by measuring pressure at the sacral and gluteal areas (sacral areas recover more slowly than gluteal areas after pressure is released). A temperature increase is seen that corresponds with an increased blood flow after pressure is removed 46 •

87 Journal of Tissue Viability 1993 Vol. 3 No 3 It has been demonstrated that pressure at the seating is reduced by Electrical Muscle Stimulation (EMS) 47 • This in turn may be< explained by the observation (by ultrasound imaging) that the shape of the buttocks is altered during EMS 48 • Ultrasound has also been employed to measure the soft tissue over the sacral area 49 (the level of soft tissue cover was lower patient who had sores).

Nutrition In commentaries going back to the 19th Century the effect of nutrition on ulcers and other wounds has been discussed 50• In many studies going back to at least the 1930's, the effects of protein 51 •52•53 .54 and vitamin C 55 have been measured. In animal studies the strength of wounds and the healing rates were shown to be related to levels of serum protein, and that correction of this deficit significantly improved healing and wound strength 52•53•54• In more recent studies the nutritional status of a patient has been shown to be associated with an increased likelihood of decubitus ulcer formation. Pinchcofsky et al 56 found that all patients with severe pressure sores were malnourished. In this large study of 232 patients of whom 17 had pressure sores, there was a significant correlation between nutritional status and the development of pressure sores. Welch et al 57 showed that the serum albumin and hrematocritof residents receiving nutritional supplements was significantly improved, with a complete or partial healing of the decubitus ulcers of 10 residents. Breslow et al 58 • 59 showed that patients with sores had lower biochemical measures of nutrition (serum albumin, cholesterol e.g.) than controls, despite having higher intakes (these were tubefed patients). Further there was a significant negative correlation between albumin levels and the area of the sores. In a further study of 10 patients with decubitus ulcers there was a similar dietary intake compared with a control group, but significantly lower levels of plasma iron and zinc60 • As the presence of pressure sores may be the cause rather than the effect of poor nutrition, prospective studies arc needed. In one such study 61 , the nutritional status of newly admitted patients without pressure sores was studied weekly. There was a lowering of the dietary intake of all the nutrients measured (serum total protein and serum albumin, serum iron, zinc and copper, and serum vitamin C) in the patients who developed pressures sores. The best dietary predictor was dietary protein intake. Other predictors found were diastolic blood pressure and temperature. The hydration of patients has been shown to be significant in predicting pressure sores 62 • Pressure sore prediction using a variety of parameters including nutritional status has been effective 63 • Biochemistry Various chemicals in the body are affected by, or predispose to decubitus ulcers. Alpha and beta adrenergic receptors in SCI patients have been implicated in skin breakdown 64 • Thromboxane levels have been shown to be elevated in pressure wounds, and it is suggested that arachidonic acid metabolites are mediators of dermal ischaemia 65 •

Plasma fibronectin has been shown to be raised in fast-healing sores, but to have lower values in poor-healing sores, and may thus be used as a predictor of healing 66 • Serum cortisol has been shown to be associated with pressure sore formation, a high level predisposing to a higher probability of sore formation. Furthermore levels were higher in the first days of admission to a nursing home, the hypothesis being that stress on admission raises levels 67 • Thus reducing stress in newly admitted patients may be a preventive measure. The effective implementation of antibiotics in treating an infected pressure sore requires the levels of drugs in the interstitial fluid be measured 68 , as the serum level may show complicated relationships with the in the interstitial fluid.

Blood Flow The oxygenation of the blood is both affected by pressure, and, prior to pressure being applied, affects the time period required to cause tissue damage when the circulation is compromised. Patients with poor circulation to the buttocks have an increased chance of developing sores 69 • Patients at risk of sore development have been independently shown to have low blood flow 70 • The blood supply has been shown 57 to be in need of improvements in patients with pressure sores, and the blood flow may be measured crudely as in diastolic blood pressure, where it has been found reduced in patients with decubitus ulcers, and locally by the laser-Doppler technique 71 • Cutaneous blood supply measured by the laser-Doppler method, and subcutaneous blood supply measured by the Xe 133 washout technique 72 have been used to assess the affect of pressure reducing surfaces on the blood supply. In a study where blood flow was measured by radio-active tracer clearance 73 , blood flow was shown to be increased in at risk areas such as the ischial tuberosity, by electrical muscle stimulation (EMS). Geriatric patients with pressure sores have lower diastolic blood pressure than controls, and there is a significant relationship between a low diastolic pressure and low cutaneous blood circulation measured by laser-Doppler 74 • Resting blood flow is low among the elderly, particularly men. Post-reactive hyperaemia was also impaired in the low diastolic group of patients. The measurement of transcutaneous oxygen tension P0 2 has shown that the PO 2 decreases to zero under bony prominences 75 and this measure may be used to calculate the danger of sore formation on mattresses etc. that are designed as pressure reduction surfaces 76 , and to assess surgical repair procedures 77 • When laser-doppler blood flow is used, it should be noted that low blood flow may still lead to ischaemia (ie prior to full capillary closure there may be insufficient blood circulating, a non-zero blood flow may be associated with zero P02 78 ).

Temperature The temperature of the skin is affected by the blood circulation in the tissue, and hence temperature is an indirect measure of blood flow. It has been used to evaluate the effects of massage 79 (extended massage decreases skin temperature of the sacral area, and hence by inference reduces blood supply).

Journal of Tissue Viability 1993 Vol. 3 No 3 88 Thermography allows one to measure blood flow to the skin, and to identify at-risk patients 80• 8 t. Erythema

As reddened areas (other than reactive hyperaemia) are considered grade one pressure sores, one might expect many studies where colour is measured. However it is typically either ignored, or mentioned but not measured. ASSESSMENT OF RISK OF DEVELOPING INCONTINENCE DERMATITIS Incontinence dermatitis in a long stay environment was found to be a more prevalent condition than decubitus ulcers to. There are fewer references to specific assessment methods for incontinence dermatitis. It has far less serious morbidity and mortality; it is more readily treated though. Decubitus ulcers are common in acute elderly patients, especially early in admission 22, and cause considerably more pain and cost. Incontinence dermatitis nevertheless requires addressing simply because of the size of the problem.

Lyder etal 82 studied the number of patients developing perineal dermatitis to give predictive parameters. It was concluded that where faecal and urinary incontinence co-existed there was a rapid development of the dermatitis (within 2 days). However the small numbers in the trial (15 patients, 5 with perineal dermatitis) make any conclusion difficult to justify. If the presence of urine on the skin causes the formation of

dermatitis then any incontinence pads should have minimal leakage for optimal skin protection. One may , as in Clancy et al 83 measure leakage. It was found that mere bulk of absorbent material was not the relevant factor in reducing leaks. The proper securing of the pad, and the design of the pad was found to be important. Clearly, however, the pad must be sufficient to absorb the urine most of the time, and it has been shown that a pad should hold at least 350g of urine for long-stay geriatric patients 84 • Laboratory tests should be developed as there are too many products to perform clinical trials on all of them, through laboratory tests on pads, while useful, do not always correlate well with clinical experience 84• Subjective assessment of the skin has been used to compare incontinence pads 85• 86• 87 • ASSESSMENT OF EXISTING CONDITIONS Traditionally one assesses both the severity of dermatitis and sores subjectively by eye. Subjective assessment may be inappropriate in conducting clinical trials for the following reasons. 1. Intra-observer error. The assessment is subjective.

2. Inter-observer error. Different observers will give different views as to the extent , colour etc. 3. Accuracy. The size of sores, the colour of skin is recorded in very crude terms such as 'small', 'reddened', etc. 4. Time Scale. If crude inaccurate unreliable data is used, largenumbersofpatientsrequiretobefollowedforextensive periods of time for meaningful statistical analysis to be obtained. This is not only expensive of resources, but allows a high drop-out rate to occur (in a 14 day study of 67 elderly patients there was a 15% drop-out due to death, illness, discharge etc to.

If studies are completed using subjective measures it is likely

the results will be inconclusive. It is noteworthy that after one excludes case studies, there have been very few studies of the efficacy of either incontinence treatment and prophylaxis (typically barrier creams) or treatment for pressure sores. To achieve a meaningful result for (say) a double blind study in either of these areas, in a reasonable time scale one needs sensitive and accurate measures of the state of the skin and the progress of a sore. One should note that sores take typically 4 months to heal, in a study of elderly nursing home residents with pressure sores 88 the median time for a sore to persist was 79 days, and very few healed in under 30 days (there are differences between healing rates in different disease states in leg ulcers 89 , and this probably applies to decubitus ulcers), so accurate measures of size are needed, as in a study period of (say) a few weeks the patient will have a sore all the time, and one needs to know the direction and speed of healing, to assess a product. Size

The size of a sore may be used to measure the healing rate of a sore. In a clinical study one would wish to use these measurements to establish that a particular treatment is superior tosomeothermethod(parallelstudy)ortosomeplacebo 90 • There is little point simply reporting that a sore healed at a certain rate (as in Goren 9 t) unless there is some control and/or comparison in the study. In a clinical setting the measurement is meaningful on its own as an indicator of improvement. The method used should however be evaluated so that appropriate error bounds may be placed on the measurement, and undue reliance is not placed on small fluctuations within the error of the method. Simple measurement

One may measure the diameter of a wound using a ruler or trace , the wound with a transparent film. A review of such measurement techniques may be found in Anthony 92 and some references are also given in Barnes et al 93 • While these techniques have been used to measure decubitus ulcers and varicose ulcers, there is no reason why most of these methods cannot be employed to measure the area of erythema, dermatitis etc. Volume measurement

Theareaofasoremaybeapoorguidetoitsextentassubcutaneous tissue is more prone to pressure damage than skin 94• Thus photography, diameter measurement and other one or two dimensional methods, while acceptable for shallow sores, are increasingly problematic with deep sore. One may use saline to fill a sore, and extract the fluid in a syringe to measure the volume, and this has been shown to be reproducible 94• There are problems with this technique, as the wound may absorb fluid, and the method may disturb the wound 95 • Dental impressions have been used to measure volume of sores 96, though this will only be appropriate for cavity sores, and will have inaccuracies as the level of the sore surface to the surrounding skin will be a subjective assessment.

89 Journal of Tissue Viability 1993 Vol. 3 No 3 Photography Photography has been {'Jllployed to give evidence of healing
need to use real-world data to assess a technique, and not to rely solely on laboratory or simulated data. The much simpler methods of wound tracing and the measurement of diameters were found to be much worse. Interestingly the tracing method was significantly worse than the diameter method. Both intra and inter observer error was considered and using the tracing technique different subjects (nurses in this case) gave areas that could be as much as 3 times as large as another subject using the same sore data. Clearly such inaccurate methods are likely to confuse the clinical picture giving(e.g.) false hopes that a sore is healing. A method where the subjective element of the measurement is taken out was suggested 92• 116 • Such a technique (see Colour-coded structured light, above) using structured light, has been employed, and compares well with other techniques, though is less accurate than photogrammetry 95 • Temperature Thermography allows one to not only predict the patients who may develop sores, but to assess the patients who currently have a sore, as those with a temperature difference of a degree or so from the sore to the surrounding tissue are likely to hcal 117 • Blood Flow Though blood flow has been used mainly to determine the preventative benefits of various mattresses etc. there is scope for using it in a similar fashion as thermography in the evaluation of healing potential of a developed sore. Ifthere is an inadequate blood supply one should be alerted to the root cause (eg low blood pressure, use of toxic local antiseptics etc) and be in a position to correct the low blood flow. Colour As noted above the colour of skin may be used to give a parameter of erythema. This is used subjectively in assessment of incontinence dermatitis, but a more objective method is preferable forreasonsoutlinedabove. Colour has been measured in patients with TB, using an industrial colour measuring device 118 • Colour has been shown to be associated with temperature in experimentally induced erythema 119, where a qualitative association was found between temperature and the erythema size and intensity. The measurement of erythema of the skin of the elderly incontinent patient was achieved by Anthony et al 10 , but modifications were necessary. The Lovibond industrial tintometer used in this study is designed to be used on static inanimate objects such as ceramic. The principle of the technique is to compare the reflected light from the specimen with that created by a light source and three sets of colour filters as shown in Figure 1. Here the view is split into two, the top half being from the specimen, the bottom that generated from filters. The values of the filters and the light intensity give a three dimensional (one colour or the intensity is omitted) data set, from which one may calculate the internationally agreed colour

Journal of Tissue Viability 1993 Vol. 3 No 3 90 scheme (Colorimetry Committee of the Commission International de L'Eclairage 1971) t 20• Figure 2 shows the readout one might see at the machine. To use the tintometer on a human, one must adapt the apparatus to keep the probe off the skin (as it would affect the blood circulation, and hence the reading) but keep the distance from the skin constant (as the distance affects the light intensity reflected back) see Figure 3 where a pair of pencil torch beams converge to form a focus, thus allowing a constant distance to be used.

As the distance from probe to the skin was difficult to maintain constant due to the patient's movements etc., the light intensity reflected was found to be highly variable, and of doubtful use. The yellow component was fairly static, and the most variable component was the red one. Rather than use the international components it was found that using the difference between the red and yellow components gave a satisfactory and simpler (one dimensional) parameter. This is unsurprising in the context of erythema as one is measuring redness.

specimen

Light passes through

Skin Morphology

adjustable filters

If skin is subject to excoriation one may expect the numbers of

Figure 1. View down Tintometer Probe

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Yellow Yellow, red and light intensity recorded. Red

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Excess Red score most useful parameter

Blue

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Figure 2. Tintometer Readout. Blue is not used. In this example there is a red excess indicating erythema. In normal skin the red and yellow values are approximately equal. Measuring probe

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It was found that using such a technique, areas noted as having erythema gave significantly different colorimetric readings than control areas with no erythema, and the readings taken from decubitus ulcers were different from both erythema and control areas. Furthermore the technique gave significantly different values for two groups of patients being treated with different barrier creams to. It has also been used subsequently to measure the effects of incontinence pads on the skin ss.

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Beams converge

Figure 3. Tintometer Probe Configuration.

desquamating skin cells (corneocytes) to be increased, and the percentage of immature skin cells (parakeratotic cells) to increase. The corneocytes are anucleated and the parakeratotic cells still retain their nucleus. A cross-section of the skin is shown in Figure 4. There is a method of assessing both these parameters tlt, and this was used in a study on incontinence dermatitis to. Essentially one scrubs the skin with a mild detergent, and the collected fluid is stained to show the cells under microscopy. A count of the corneocytes, and the percentage of parakeratotic cells showed no significant increase in areas of erythema, or areas close the decubitus ulcers, compared with control areas. A high percentage of parakeratotic cells was noted in a case of severe erythema under the breasts of one patient, but in typical incontinence associated dermatitis the technique did not appear to be useful as a parameter. This does not mean the technique should not be considered in other cases of erythema or dermatitis, and it may be that, more acute skin conditions may be suitably assessed using this technique. It has been used to show a null result, ie, that incontinence pads do not produce florid skin changes ss. Bacterial Analysis of the skin Using the fluid obtained by the detergent scrub technique used for measuring corneocyte and parakeratotic cells counts, several tests were made quantitatively and qualitatively to. The aim was to establish whether the skin of the incontinent patient over the ischial tuberosity, or at sites of erythema or pressure sores showed any divergence from control sites. The aim was to establish whether the skin of the incontinent patient over the ischial tuberosity, or at sites of erythema or pressure sores showed any divergence from control sites .

There were not any significant qualitative findings in the bacteriology of the incontinent patient's ischial tuberosity area. There were some (probably opportunistic) infections in some of the erythematous are~. but on the whole the main point of note was how normal the bacteriology appeared. Quantitatively the bacterial counts were highly variable, but parametric testing showed that over a trial period overall the

91 Journal of Tissue Viability 1993 Vol. 3 No 3

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Section of the skin Figure 4 Cross Section of the Skin counts were reduced by the application of both barrier creams, but that one was significantly more reduced with respect to bacterial counts than the other. Overall the bacterial density reduced with respect to bacterial counts the other. Overall the bacterial density reduced over the 2 week period from 104 to 103 for both groups combined 9• CONCLUSION Various methods exist for assessing the possibility of skin breakdown that may cause dermatitis or, worse, decubitus ulcers. These methods include:Scoring systems based on general condition of patient, mobility etc. Interface pressure Nutritional status, especially serum protein levels Biochemical testing of various chemicals in serum and interstitial fluid Local blood flow measurement Temperature Erythema Currently methods for assessing the progress of either a dermatitis or a sore include

•

Corneocyte counts and parakeratotic cell ratios (this may be useful in florid conditions, but has not shown benefit in incontinence dermatitis as normally found) Lesion size Bacterial testing Colorimetry of the skin/ulcer

There has been little work done on the assessment of sores, and even less on incontinence dermatitis, at the microscopic level, and the measurement of erythema by colorimetry has received scant attention. It would be very useful if a portable device that measured colour and sore size could be developed to measure the lesion extent and level of erythema. This could be employed in clinical trials, and if it were made robust enough and simple to use, could be used to assess clinical progress of a patient. ADDRESS FOR CORRESPONDENCE Dr D Anthony, Computing Services, University of Warwick, Coventry

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the seating interface. J Rehabil Res Dev, 1989; 26: 1-8. 48. Levine S P, Kett R L, Cederna P S, Brooks S V. Electric muscle stimulation for pressure sore prevention: tissue shape variation. ArchPhys MedRehabil, 1990; 71:210-15. 49. Clark M, Rowland L B, Wood H A, Crow R A. Measurement ofsoft tissue thickness over the sacrum ofelderly hospital patients usingB mode ultrasound J BiomedEng, 1989; 11:200-2 50. Paget J. Clinical lecture on bed-sores. Student's Journal and Hospital Gazette (London), 1873; 1: 144-6. 51. Thompson W B, Ravdin IS, Frank I L. Effect of hypoproteinaemiain wound description. ArchSurg, 1938; 36: 500-98. 52. Thompson W D, Ravdin IS, Frank I L. Use of lyophile plasma and prevention of wound disruption. Arch Surg, 1938; 36: 509-18. 53. Mulholland J, Co Tui, Wright A, Vinci V, Shafiroff B. Protein metabolism and bed-sores. Ann Surg, 1943; 118: 1015-23. 54. Harvey S C, Howes E L, Effect of high protein diet on the velocity of growth of fibroblasts in the healing wound. Ann Surg, 1930; 91: 641-5. 55. Lamman TH, Ingalis TH. Vitamin C deficiency in wound healing. Ann Surg, 1937. 105: 616. 56. Pinchcofsky Devin G, Kaminski Jr MV. Correlation of pressure sores and nutritional status. JAm Geriatr Soc, 1986; 34:435-40. 57. Welch P K, Dow son M, Endres J M. The effect of nutrient supplements on high risk long term care residents receiving pureed diets. J Nutr Elder, 1991; 10: 49-62. 58. Breslow R A, Hallfrisch J, Goldberg A P. Malnutrition in tubefed nursing home patients with pressure sores. J Parenter Enteral Nutr, 1991; 15: 663-8. 59. Breslow R A. The effect of dietary protein intake on pressure sore healing and nutritional status in nursing home subjects. PhD thesis, UniversityofMarylandCollege Park, 1990. 60. Williams CM, Lines CM, McKay EC. Iron and zinc status in multiple sclerosis patients with pressure sores. Eur J ClinNutr, 1988; 42:318-21. 61. Bergstrom N, Braden B. A prospective study of pressure sore risk among institutionalised elderly. JAm Geriatr Soc, 1992; 40: 747-58. 62. Kirschner MT. The relationship between serum albumin and total protein on the development of pressure sores. Master's thesis, South Connecticut State University, 1990. 63. Chao Yann-Fen Chiou. A predictive scoring system for selected complications of ICU patients. PhD thesis, Rush University, College of Nursing, 1991. 64. Rodriguez G P, Claus Walker J, Kent M C, Stal S. Adrenergic receptors in insensitive skin of spinal cord injured patients. Arch Phys MedRehabil, 1986; 67: 177-80. 65. Vaughn D M, Swaim SF, Milton J L. Elevation of thromboxane in pressure wounds. Prostaglandins Leukot Essent Fatty Acids, 1989; 37: 45-50. 66. Vaziri N D, Eltorai I, Gonzales E, Winer R L, Pham H, B ui T D, Said S. Pressure ulcer, fibronectin, and related proteins in spinal cord injured patients. Arch Phys Med Rehabil, 1992; 73: 803-6. ' 67. Braden B J. The relationship between serum cortisol and pressure sore formation among the elderly recently relocated to a nursing home. PhD thesis, The University of Texas at Austin, 1988. 68. Segal J L, Brunnemann S R, Eltorai I M. Pharmacokinetics of amikacin in serum and in tissue contiguous with pressure

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89. Atri S C, Misra J, Bisht D, Misra K. Use of homologous platelet factors in achieving total healing of recalcitrant skin ulcers. Surgery, 1990; 108: 508-12. 90. Robson M C, Phillips L G, Thomason A, Altrock B W, Pence PC, Heggers J Petal. Recombinant human platelet derived growth factor bb for the treatment of chronic pressure ulcers. Ann Plast Surg, 1992; 29: 193-201. 91. Goren D. Use of Omiderm in treatment oflow degree pressure sores in terminally ill cancer patients. Cancer Nurs, 1989; 12: 165-9. 92. Anthony D. The accurate measurement of pressure sores. In Fielding P editor, Research in the Nursing Care of Elderly People. John Wiley, 1987; 1-25. 93. Barnes E, Anthony D, Exton-Smith AN, Malone-Lee J. An accurate method of measuring pressure sores. Paper presented to The Tissue Viability Society, UK, 1984. 94. Berg W, Transeroth C, Gunnarson A, Lossing C. Method for measuring pressure sores. The Lancet, 1990; 335: 1445-6. 95. Plassmann P, Jones B F, RingE F J. An assessment of a non-contact instrument to measure the volume of leg ulcers. In Proc ofthe 2nd!nt Confon Wound Management, Harrogate, 1992. 96. Covington J S, Griffin J W, Mendius R K, Tooms R E, Clifft J K. Measurement of pressure ulcer volume using dental impression materials: suggestion from the field. Phys Ther, 1989; 69: 690-4. 97. Itoh M, Montemayor Jr J S, Matsumoto E, Easton A, Lee M H, Folk F S. Accelerated wound healing of pressure ulcers by pulsed high peak power electromagnetic energy (diapulse). Decubitus, 1991; 4: 24-5, 29-34. 98. Sehorn MD. Pressure ulcer management in home health care: efficacy and cost effectiveness of moisture vapor permeable dressing. Arch Phys Med Rehabilitation, 1986; 67. 99. Maklebust J. Pressure ulcers: etiology and prevention. Nurs Clin North Am, 1987; 22: 359-77. 100. Anthony D, Barnes E. Measuring pressure sores accurately. Nursing Times, 1984; 80: 33-5. 101. Griffin J W, Tooms R E, Mendius R A, ClifftJ K, Vander Zwaag R, el Zeky F. Efficacy of high voltage pulsed current for healing of pressure ulcers in patients with spinal cord injury. Phys Ther, 1991; 71:433-42. Discussion442-4. 102. Chiu W C, Anthony D M, Hines E L, Forno C, Hunt R, OldfieldS. Selection of the optimal mlpnetforphotograrnmetric target processing. In Iasted ConfArtificial Intelligence App & Neura!Networks,p 180-3,1990. 103. Attallah NL, Marshall W A. Estimation of chronological age from different body segments in boys andgirlsaged419 years, using anthropometric and photogrammetric techniques. Medicine Scienceand the Law, 1989; 29: 147-55. 104. Pflugfelder S C, Roussel T J, Denhem D, Feuer W, Manfelbaum S, Pare! J M. Photogrammetric analysis of corneal trephination. Archives of Opthalmology, 1992; 110: 1160-6. 105. Chadwick R G. Close range photogrammetry- a clinical dental research tool. Journal ofDentistry, 1992; 20: 235239. 106. Boulianne M, Cloutier L, Ghosh S K. Cerebral biopsies using a photogrammetric probe simulator.?hotogrammetric Engineering and Remote Sensing, 1991; 57: 1347-54. (Continued on page 99)

99 Journal of Tissue Viability 1993 Vol. 3 No 3 hydrogel was applied, starting on the fourteenth of twenty treatments. Although the reaction continued to increase during the treatment, the skin remained intact, with no moist desquamation, and the irritation and burning were soothed and cooled. The patient was delighted with the relief obtained. On completion of the main course of radiation, the area was judged too sore to allow a "boost" dose to be given to the lumpectomy scar and the patient was reviewed at one week, having continued to use the new hydrogel. In a previous study, smokers had been observed to have an increasing reaction for at least ten days after treatment; however, this patient showed her skin intact, and erythema less at one week. The boost was then given. The fourth patient complained of intense burning sensation over part of the treated area. The new hydrogel was applied to this during the day, and was described by the patient as "bliss". She found it very easy to use. The fifth patient presented three weeks after completion of a course of radiotherapy to her neck with a very crusty reaction. It was causing acute discomfort and was very painful when touched or when she moved her head. The new hydrogel was applied and five days later the area was well-healed, but the patient reported that the pain and discomfort had been relieved within twelve hours of the first application. The sixth patient was receiving radiotherapy to his lower humerus, with bolus being applied to the scar on the medial aspect. The skin on the scar broke at fraction eighteen (of thirty). The new hydrogel was used , and although the scar became infected (for which oral antibiotics were prescribed), the area of moist desquamation did not increase, and the surrounding skin which was included in the radiation treatment remained intact. The site of the scar was such that it could have impaired mobility of the elbow joint, but the use of the new hydrogel helped keep the scar and skin soft, and the patient even managed to have skiing lessons during the course of his radiotherapy!

(Continued from page 93) 107. Diliberti J H, Olson D P. Photogrammetric evaluation in clinical genetics - theoretical considerations and experimental results. American Journal of Medical Genetics, 1991; 39: 161-6. 108. Grun A, Niederer P. Photogrammetry and remote-sensing in medicine- biostereometry and medical imaging. ISPRS JournalofPhotogrammetryandRemote Sensing,1990; 45: 109. Turnersmith A R. X-ray photogrammetry of artificial joints. Photogrammetric Record, 1990; 13: 347-66. 110. Fraser C S. Photogrammetric measurement to one part in a million. Photogrammetric Engineering and Remote Semsing, 1992; 58: 305-10. 111. B ulstrode C J K, Goode A W, Scott P J. Stereophotogrammetry for measuring rates of cutaneous healing; a comparison with conventional techniques. Clin Science, 1986; 71: 437-43. 112. Plassmann P,Jones B F. Measuring leg ulcers by colourcoded structured light. J Wound Care, 1992; 1: 35-8. 113. Boyer K L, Kak A C. Colour-encoded structured light for rapid active ranging. IEEE Trans, 1987; PAMI-9: 14-28.

DISCUSSION The above experiences suggest that the new hydrogel may have a considerable role to play in making radiation treatment more comfortable and acceptable for those patients who suffer skin symptoms. All patients who have received applications found it soothing, cooling and liked the feel of it on their skin; It is also possible that, by using the new hydrogel on patients who complain of symptoms, but have not developed moist desquamation, the new hydrogel may prevent the skin breaking. One problem that does arise is that of keeping the dressing in place. If it placed over a small part of a larger radiation treatment area, then any tape used will often be adhering to sensitised skin. A large dry dressing over the radiated area, allowing taping to unaffected skin, should not be recommended, as a cool air flow over the skin, with lack of friction from materials, helps minimise reactions. One possible solution for some sites might be to use something like "netelast", but this again is not always comfortable without a large dressing. CONCLUSIONS This centre is continuing to explore the application of the new hydrogel, both as a healing agent in moist desquamation, and as a soothing agent and possibly in a preventative role to keep skin intact.

Editor's note: The new hydrogel referred to in the article is 2nd Skin. Its American name is Vigilon and it is manufactured by Seton Health Care. ADDRESS FOR CORRESPONDENCE Ms J Crane, Superintendent Radiographer, Royal United Hospital, Combe Park, Bath BAl 3NG REFERENCES 1. Campbell IR & Illingworth MH. Can patients wash during radiotherapy to the breast or chest wall? A randomised controlled trial. Clinical Oncology ,1992; 4: 78-82. 2. Crane J. Does smoking increase radiation skin reaction? Radiography Today, 1992; 58: 20-3. 3. Thomas S. Current practices in the management of fungating lesions and radiation damaged skin. The Surgical Materials Testings Laboratory 1992. 114. Plassman P. Personal communication. 115. Thomas A C, Wysocki A B. The healing wound: a comparison of three clinically useful methods of measurement. Decubitus, 1990; 3:18-20,24-5. 116. Anthony D. Measuring pressure sores. Nursing Times, 1985; 81: 57-61. 117. Barton A A , Barton M. The clinical and thermographic evaluation of pressure sores. Age and aging, 1973; 2: 55-9. 118. Pearson CA. Hypochromia as a clinical sign of tuberculosis in the tropics. Tubercle, 1978; 59: 111-9. 119. Finestone H M, Levine S P, Carlson G A, Chinzky K A, Kett R L. Erythema and skin temperature following continous sitting in spinal cord injured individuals. J Rehabil Res Dev, 1991; 28: 27-32. 120. Commission Internationale de L'Eclairage. Cororimetry by committee 1.2.1. Bureau Central de la CIE, 4 Ave du Recteur Poincare 75, Paris, 1971. 121. McGinley K J, Marples R R, Plewig G. A method for visualising and quantifying the desquamating portion of the human Statum corneum. TheJ oflnvestiDermatol, 1969. 122. Noble W C. Microbiology of human skin, volume 2 of Major problems in dermatology. Lloyd-Luke, 1981.