The cost of pressure ulcers is high, both in terms of suffering caused to the patient and the financial burden on society and the patient (Bennett, Dealey, & Posnett, 2004; Edwards, 1994; Hopkins, Dealey, Bale, Defloor, & Worboys, 2006; Langemo, Melland, Hanson, Olson, & Hunter, 2000; Nixon et al., 2006; Thomson & Brooks, 1999). Pressure ulcer prevalence ranges from 2.3 to 28% in long-term-care facilities (Coleman, Martau, Lin, &Kramer, 2002; Lahmann, Halfens, &Dassen, 2005). Incidence figures on intensive care wards vary between 8 and 40% (National Pressure Ulcer Advisory Panel, 2001). Prevention of pressure ulcers is important from the viewpoint of the patient, care provider, and society.
According to a report from the Dutch Health Council, pressure ulcers are responsible for 1.3% of the total costs of Dutch health care and for this reason rate among the top four illnesses as far as costs are concerned. In this study no account has been taken of the nonmedical costs (paid by the patient) and productivity costs (costs of absenteeism as a result of poor health) (Health Council of the Netherlands, 1999; Severens, Habraken, Duivenvoorden, & Frederiks, 2002).
The American Healthcare Cost and Utilization Project reported a mean length of stay for hospitalizations specifically for pressure ulcers of 13 days, and an average charge of $37,800 (Russo & Elixhauser, 2006). The lowest possible incidence of pressure ulcers in geriatric care can only be achieved if an effective prevention policy is carried out well. This requires a coordinated approach in which account is taken of both effectiveness and the practical feasibility of the preventative measures.
Figure·1 Conceptual model.
A pressure ulcer is a degenerative change of tissue that originates from a deficiency of oxygen arising from pressure and shearing force (Defloor, 1999; European Pressure Ulcer Advisory Panel, 1999). These forces inhibit the blood supply to the tissue through pressure closing and/or shear closure of the blood vessels (see Figure.1). Whether this will eventually result in a deficiency of oxygen in the tissue cells is influenced by the duration and intensity of the pressure and shearing force and by the tolerance of the tissue to these forces. Compressing force is defined as a force that places a vertical load onto the tissue, whereas shearing force is a force that places a parallel force on the tissue.
A compressing force higher than the capillary pressure will curb the flow in the capillaries and lymphatic vessels, resulting in, on the one hand, an insufficient oxygen and nutrition supply and, on the other hand, an inadequate drainage of waste products. Perpendicular forces exerted on the skin above a bone part unite in a small area of the subcutaneous fat and muscular tissue just above the bone part. The pressure exerted on the skin becomes greater by a factor of 3 to 5 in the tissue at the bony projection (Welch, 1990). The pressure thus increases with the depth of the tissue. It is smallest on the skin and greatest at the underlying bone tissue. This is one of the reasons why extensive damage can occur in deep tissues, without the skin being affected. This effect is stimulated further by the fact that the skin is mechanically stronger than the deeper lying tissues and in a better state to withstand periods of ischemia.
Shearing force is a mechanical burden that is exerted through forces parallel to the surface. Shearing forces occur from a half-sitting position in a bed or armchair. The skeleton and the deep fascia slide downward here because of gravity; the skin and superficial fascia do not slide along with it because of the higher friction coefficient of seat or mattress. This movement of two tissue layers in relation to each other leads to stretching, kinking, and possible tearing of the perforated veins in the subcutaneous tissues, through which a deep necrosis can originate.
Compressing force and shearing force is not sufficient to explain the origination of pressure ulcers completely. Other factors (tissue tolerance) also appear to play a role in this process. Tissue tolerance contains a number of risk factors that are known or suspected of influencing the individual’s risk of getting pressure ulcers, without being directly influenced by the magnitude or duration of the compressing force and/or shearing force (Defloor, 1999).
The extent to which the exerted pressure will be enough to cause the occurrence of pressure ulcer injury is influenced by the tissue tolerance for pressure. Decrease in the tissue’s capacity to dissipate pressure is linked to increased age, dehydration, protein and vitamin deficiency, and stress. Because of the presence of more of these factors, for example, age, diminished skin elasticity, cardiovascular problems, multipathology, decreased mobility, the older adult has an increased risk of the development of pressure ulcers: Specific risk factors for the critical care population are duration of surgery and number of operations, fecal incontinence and/or diarrhea, low preoperative protein and albumin concentrations, disturbed sensory perception, moisture of the skin, impaired circulation, use of inotropic drugs, diabetes mellitus, too unstable to turn, decreased mobility, high APACHE II score, history of vascular disease, intermittent hemodialysis, continuous veno-venous hemofiltration, mechanical ventilation (Keller, Will, van Ramshorst, & van der Werken 2004; Nijs et al., 2009).
So long as the supply of oxygen to the tissue meets its needs, no pressure ulcer occurs. If, however, either the oxygen supply drops, or the tissue’s oxygen needs increase, an oxygen deficiency can occur and the risk of pressure ulcer increases. Tissue tolerance to changes in oxygen concentration will be determined by whether the oxygen deficiency can be neutralized or not.
Observation of Pressure Ulcers
The observation and correct classification of pressure ulcers is important in deciding whether to start prevention and treatment in good time or to intensify it.
Classification of Pressure Ulcers
Classifying pressure ulcers is done, on the one hand, by evaluating the seriousness of a pressure ulcer injury and, on the other hand, by being able to determine if a skin injury is a pressure ulcer injury or not. A classification system contains a number of grades (or stages). This numerical classification is done on the basis of the gravity of the tissue damage. The higher the grade the greater the tissue damage.
There are many classifications of pressure ulcers (David et al., 1983; Haalboom et al., 1997; Panel for the Prediction and Prevention of Pressure Ulcers in Adults,1992; Shea, 1975: Torrance, 1983). Some classification systems are so extensive that, in practice, they are difficult to manage and do not lead to a uniformly correct classification of pressure ulcer injuries. In 1975 Shea, an orthopedic surgeon, first published a pressure ulcer classification system. He divided pressure ulcers into five stages based on the damage to the various tissue layers and the depth.
Most classification systems are based on Shea’s work and employ four to five stages (Maklebust & Sieggreen, 1995; Reid & Morison, 1994; Shea 1975). A few systems distinguish six stages, in which still further subgradations are used. The most complex system was Stirling’s, which has four stages, in which for each stage up to four subcategories were defined (Lowthian, 1987; Reid & Morison, 1994; Yarkony et al., 2007).
In the United States, NPUAP’s (National Pressure Ulcer Advisory Panel’s) classification is employed (Panel for the Prediction and Prevention of Pressure Ulcers in Adults, 1992). In Europe, the most frequently used classification system is that of the EPUAP (European Pressure Ulcer Advisory Panel, 1999). Both classifications distinguish four grades or stages. The definitions differ from each other to a minimal extent and are almost identical.
In 2007 the NPUAP confirmed the four stages and added in its staging system a new type of pressure ulcer: the “suspected deep tissue injury” (DTI) (NPUAP, 2007). This is defined as a purple or maroon localized area of discolored intact skin or bloodfilled blister caused by damage of underlying soft tissue from pressure and/or shear. The area may be preceded by tissue that is painful, firm, mushy, boggy, warmer, or cooler as compared to adjacent tissue. DTI may be difficult to detect in individuals with dark skin tones. Evolution may include a thin blister over a dark wound bed. The wound may further evolve and become covered by thin eschar. Evolution may be rapid, exposing additional layers of tissue even with optimal treatment.
When, after a period of pressure load, the pressure is removed, there is a reactive hyperemia or pressure-related blanchable erythema. This increased blood flow to the tissue is a protective autoregularization mechanism that corrects the deficiency of oxygen in the tissue (Bliss, 1998; Michel & Gillot, 1992; Nixon & McGough, 2001). This redness is called pressure-related blanchable erythema because it becomes white when pressed with the finger or with a transparent disk. Pressure-related blanchable erythema is not considered to be a pressure ulcer. Pressure ulcers are classified into four grades or stages on the basis of the seriousness of the injury (see Figure.2): pressure related-nonblanchable erythema (stage 1), blister or abrasion (stage 2; see Figure.3), superficial pressure ulcer (stage 3; see Figure.4), and deep pressure ulcer (stage 4; see Figure.5) (European Pressure Ulcer Advisory Panel, 1999).
A stage 1 (pressure-related nonblanchable erythema) is redness that does not become white when pressed and matches the discoloration of the skin, has warmth, edema, or hardening of the tissue. Pressure-related nonblanchable erythema is easy to observe and is generally considered the most important symptom of a stage 1 pressure ulcer in Caucasians. In patients with dark skin, other symptoms become more important (Panel for the Prediction and Prevention of Pressure Ulcers in Adults, 1992).
In people with a pale complexion this is clinically visible as a marked area of permanent redness. In people with darker skin it can be seen as a marked area of permanent red, blue, or purple tints. This is, however, much more difficult to see. This color change is also coupled with a change in one or more other symptoms such as skin temperature (higher or lower than the surrounding skin), tissue consistency (firm or flaccid), and/or sensitivity (pain, itch) (Panel for the Prediction and Prevention of Pressure Ulcers in Adults, 1992). In principle, pressure-related nonblanchable erythema is reversible when pressure and shear force are removed immediately after its occurrence (Halfens, Bours, & Van Ast, 2001: Maklebust, 1987; Smith, 1995; Vanderwee, Grypdonck, DeBaquer, & Defloor, 2006). Pressure-related nonblanchable erythema is an alarm signal, a time at which prevention must certainly begin (Vanderwee, Grypdonck, & Defloor, 2007). The EPUAP advises health care providers to report pressure-related nonblanchable erythema separately in prevalence measurements and not to just add them in with the other stages of pressure ulcer (Defloor et al., 2005).
Figure·2 Stage 1:
Pressure-related nonblanchable erythema.
A stage 2 (blister or abrasion) is a degeneration of the skin (partial skin swelling), including dermis, epidermis, or both. The injury is superficial and is clinically observable as an abrasion or blister. A burst blister is also catalogued as stage 2.
A stage 3 (superficial pressure ulcer) is an injury to the skin (complete skin swelling), including damage or necrosis of the subcutaneous tissue. The injury can extend up to (but not through) the underlying fascia. Clinically it is visible as a deep crater, whether or not with undermining of the adjacent tissue.
A stage 4 (deep pressure ulcer) is an injury to the skin (complete skin swelling) with extensive destruction; tissue necrosis; or damage to muscle, bone, or supporting tissue (e.g., tendon or joint capsule). Undermining of the tissue or formation of infected injury is possible The various grades or stages are regarded as manifestations of pressure ulcers, and not as phases that necessarily follow each other. Pressure ulcer can, in some patients, start as a blister, a superficial, or even deep pressure ulcer. Sometimes a blister can evolve directly into a black necrosis spot (deep pressure ulcer).
Stage 3: Superficial pressure ulcer.
Sites of Pressure Ulcers
Pressure ulcers in principle can occur on all parts of the body. Obviously pressure ulcers occur mostly around those areas that have the following characteristics:
· Bone tissue close under the skin surface;
· A relatively thin layer of fat and muscular tissue or a thick layer of fat tissue between bone tissue and skin surface;
· The surfaces of the human body.
In practice pressure ulcers occurs most frequently at the coccyx and the heels because the pressure on those locations is very high and the limited thickness of the tissue does not allow distribution of the pressure.
Stage 4: Deep pressure ulcer.
Observation Methods for Pressure-Related Blanchable and Nonblanchable Erythema
There are two methods to differentiate between pressure-related blanchable and nonblanchable erythema: the finger pressure method and one using a disk. The classic method of determining pressure blanching by redness is the finger-pressure method. With this method, pressure is carefully exerted with the finger or thumb on the red skin site. If the red skin site goes white, this is classified as pressure-related blanchable erythema (Maklebust, 1987). The microcirculation has remained intact and there is no sign of tissue damage. To discern the difference between pressure-related blanchable and nonblanchable erythema, a transparent disk (see Figures 19.6 and 19.7) can be used (Halfens et al., 2001; Vanderwee et al., 2006). A disk is a transparent roundedoff piece of plastic with a diameter of approximately 5 cm. It allows pressure to be exerted on the skin and at the same time to observe whether the skin can be pressed white or not.
The dynamic process of the blanching of the redness is visible through the transparent disk. This makes observation easier on patients on whom the whitening is only briefly visible after the removal of pressure because the blood vessels fill up quickly. More pressure points with pressure-related nonblanchable erythema can be detected using a transparent disk than using the finger method (Vanderwee et al., 2006).
Figure·6 Transparent disk.
Definition and Principle
Pressure ulcer prevention starts with detecting patients who run the risk of developing pressure ulcers. The importance of this detection is the need to provide suitable care to meet the specific needs of the patient. Moreover good risk assessment leads to the allocation of a well-considered remedy for both patient and society (Lyder, Shannon, Empleo-Frazier, McGeeHee, & White, 2002). This assessment of risk can be made on the basis of a risk scale, clinical observation, and early recognition of pressure-related nonblanchable erythema.
A risk scale is a scientifically based measurement in which indicators and factors are recorded, with the aim of identifying patients who run the risk of developing pressure ulcers (Edwards, 1994). The most extensively researched and frequently used risk scale is the Braden scale (See Table.1) (Bergstrom, Braden, Kemp, Champagne, & Ruby, 1998). The Braden scale consists of six items: sensory observation, activity, mobility, moistness, nutritional situation, and friction/shearing force (see Figure.4). Scores can vary between 6 and 23. The most used cut-off point is 17 (a patient with a score lower than 17 is considered to be an at-risk patient). A low score is associated with a greater risk of pressure ulcer (Bergstrom et al., 1985; Bergstrom, Braden, Laguzza, & Holman, 1987; Braden & Bergstrom, 1987).
Cubbin and Jackson developed a risk-assessment scale for intensive care patients. This scale is based on age, weight, general skin condition, mental condition, mobility, hemodynamic status, respiration, nutrition, incontinence, and hygiene (Jackson, 1999). This scale has had limited testing and the validation procedures used were not very adequate (Shanin et al., 2007). Shanin et al. concluded in their review on intensive care risk assessment that no effective risk assessment scales are described in the literature. Risk scales, however, often fail to predict the development of pressure ulcers adequately (Bergquist, 2001; Bergquist & Frantz, 2001; Boyle & Green, 2001; Chaplin, 1999; Defloor &Grypdonck, 2004; Galvin, 2002; Lindgren, Unosson, Krantz, & Ek, 2002; Perneger et al., 2002; Schoonhoven et al., 2002; Van Marum et al., 2000; Vap & Dunaye, 2002; Wellard & Lo, 2000). Therefore, risk scales have to be combined with clinical expertise and painstaking observation of the skin. This will reduce the number of false positives (the patients at risk based on the risk score, but who are not at risk in reality) and false negatives (the patients not at risk based on the risk score, but who are at risk in reality) (Defloor & Grypdonck, 2004). If pressure-related nonblanchable erythema is observed at pressure points, preventative measures should be started directly, even though the patient is not a risk patient according to a risk scale. It is not recommended to base the risk determination and allocation of preventive material exclusively on risk score lists (Panel for the Prediction and Prevention of Pressure Ulcers in Adults, 1992).
Combining risk scales with the clinical expertise by the nurse is recommended (CBO, 2002; National Collaborating Centre for Nursing and Supportive Care, 2003). This “clinical expertise” is a judgment by the nurse about the risk of pressure ulcers for an individual patient, based on many years’ experience and common sense. The nurse “sees” or “knows” when a patient is at risk.
According to Van Marum, Germs, and Ribbe (1992), nurses consider a patient to be at risk when he is immobile and not at risk when he has a good general physical condition. In tests where clinical expertise is compared to the use of risk scales, the results are variable (Hergenroeder, Mosher, & Sevo, 1992; Salvadalena, Snyder, & Brogdon, 1992; VandenBosch, Montoye, Satwicz, Durkee, & Boylan, 1996).
Early Recognition of Pressure-Related Nonblanchable Erythema
Observing the patient carefully on a daily basis, with prevention begun as soon as possible after a pressure-related nonblanchable erythema appears is a viabale nursing alternative to using risk scales. By definition, when prevention is started on patients who develop pressure-related nonblanchable erythema, only patients at real risk get prevention (pressure-related nonblanchable erythema points to a risk of development of pressure ulcer injuries). With this method of risk determination, fewer patients are considered as at risk than when using the classic risk scales. From research in geriatric medical and surgical-nursing units it appears that with the observation-only assessment, the number of pressure ulcer injuries stage 2 and higher did not increase as compared to using the classic risk scales (Vanderwee et al., 2007). Of course, the observation method requires that patients are observed very thoroughly and regularly (at least daily), and that immediate prevention is started on the appearance of pressurerelated nonblanchable erythema.
The Braden Scale
1. completely limited
2. very limited
3. slightly limited
4. no impairment
1. constantly moist
2. very moist
3. occasionally moist
4. rarely moist
3. walks occasionally
4. walks frequently
Friction and Shear
1. completely immobile
2. very limited
3. slightly limited
4. no limitation
1. very poor
2. probably inadequate
2. potential problem
3. apparent problem
Principles of Prevention
Pressure ulcer prevention is important but not always easy to achieve. Effective preventive measures directly influence the causes of pressure ulcers. These measures reduce the size and/or the duration of the pressure and shearing force. Measures that solely influence tissue tolerance can only be supportive measures. They can reduce the risk of pressure ulcers in limited measure, but whether they can prevent pressure ulcers in high-risk patients is rather doubtful. For effective prevention it is important that continuity of the preventive measures is guaranteed. This means that for an at-risk patient, 24 hours per day, 7 days per week preventive measures must be taken. Thus, prevention must occur both when the patient is lying in bed and when he or she is sitting up in a (wheel) chair, during transfers, and during an operation. If this does not happen, the chance is great that the patient will still develop pressure ulcers.
A distinction can be made depending on the aim of the preventive measures:
- Measures aimed at pressure
- Measures aimed at shearing force
- Measures aimed at tissue tolerance
- Other measures
Preventive Measures Aimed at Pressure
Preventive measures can focus on decreasing the duration of the pressure or decreasing the magnitude of the pressure.
Reducing the Magnitude of Pressure
The magnitude of pressure is dependent on the size of the supportive surface. If the supportive surface is enlarged, then the magnitude of the pressure that the tissue undergoes is reduced as well. Weight-spreading mattresses enlarge the support surface. The posture also has an influence on the size of the pressure (Defloor, 2000).
The pressure is lowest when a patient lies in a semi-Fowler position of 30°. In this position the head is raised up 30° and the foot of the bed 30°. In pressure ulcer prevention this position thus takes preference. The lowest pressure in lying on one’s side is measured in a 30° position. In this dorso-lateral position the patient is turned at a 30° angle to the mattress and supported in the back with a cushion that produces a30° angle. It is important to check that the sacrum is pressure free. The hand must be able to be placed between the lower layer and the sacrum and the buttock must be free.
The higher the head is raised, the greater the pressure becomes. In a 90° upright sitting position the pressure is the greatest. The pressure surface is then at it’s smallest, which results in higher pressure thereby increasing the chance of pressure ulcers occurring. When a patient needs to sit upright in bed, (for a meal, for example), a half-sitting position (60°) is recommended. When the patient is sitting the pressure is higher than while lying and the chance of pressure ulcers is great (Defloor & Grypdonck, 1999, 2000). The best position for a patient in an armchair is to have him or her sit back positioning the chair with the legs supported on a footrest. In this position the lowest pressure is measured. It is important that the heels are not supported on the footrest. Otherwise the pressure at the heels is great and pressure ulcers can originate there. If the armchair cannot be tipped backward, the pressure is lowest in an upright sitting position with the feet on the ground.
If a patient slips down in the seat or is sitting askew, the pressure increases sharply. Regular checking on this sitting position and the use of positioning cushions must be a part of every pressure–ulcer-prevention policy.
Pressure-Redistributing Mattress Systems
The pressure-redistributing system’s purpose is to enlarge the pressure surface (contact area between patient and system). There are two groups of pressure-redistributing systems: the static and dynamic systems. Static-pressure-redistributing systems will assume the shape consistent with the pressure exerted on it by the patient’s body surface. Examples of this type of mattress are foam and air mattresses. The dynamicpressure-redistributing systems are electrically driven and change form through external factors (e.g., air pump). The most important dynamic-pressure-reducing systems are the “air-fluidized” beds and the “low air-loss” systems.
Foam mattresses are static-pressure–redistributing systems that consist of viscoelastic or flexible foam. Viscoelastic foam is foam with a “slow memory” (slow foam or viscoelastic foam). This foam tries to adapt its original shape to weight and, in this way, achieve better pressure reduction. The effect is comparable to sitting on a balloon filled with sand: the sand will redistribute itself and take on a new form. The pressure reduction that viscoelastic foam mattresses achieve is real, but insufficiently large to function as the only preventive means for risk patients (Gunningberg, Lindholm, Carlsson, & Sjoden, 2000). Changing position remains necessary, albeit less frequently than on an elastic foam mattress (Defloor, Herremans, et al., 2005). Elastic foam tries to return to its original shape when weight is placed on it. Here the effect is comparable to sitting on a balloon filled with water: the water strives to go back to its original shape. A pressure reduction of 20 to 30% was observed when a subject was laid on a viscoelastic foam mattress compared with an elastic foam mattress (Defloor, 2000; Fontaine, 2000; Willems, 1995). Viscoelastic foam is also recommended for use on stretchers in emergency departments. Prevention has to start as soon as possible. If no preventive measures are taken in the ambulance and in the emergency ward, a patient may already have developed a pressure ulcer prior to being admitted to the intensive care unit. The use of viscoelastic foam on the stretchers in the emergency ward and even in the ambulance would help to reduce the pressure-ulcer risk.
Although a water mattress has a pressure-reducing effect (Neander & Birkenfeld, 1991; Sideranko, Quinn, Burns, & Froman, 1992; Sloan, Brown, & Larson, 1977; Wells & Geden, 1984), this mattress still cannot be recommended. The water mattress hampers the patient’s spontaneous position changes. It takes a lot more effort to change position or to be moved. Because of this the duration of immobilization is extended and the risk of pressure ulcers increases. Other known disadvantages of the water mattress are the weight of the mattress and the drop in temperature that it causes (Groen, Groenier, & Schuling, 1999).
The air-fluidized beds consist of a tub, a casing, and a pump system. The mattress is constructed out of silicone granules that are surrounded by a synthetic material cover (Brienza & Geyer, 2000). When warm air (28 to 35° C) is blown through the silicone granules, the silicone granules behave like a liquid. Resulting in the body being, as it were, immersed into the mattress by which means the area of body contact to the mattress is maximized. This can be described as a “quicksand” effect. Pressure redistributing is responsible for a decrease in the magnitude of pressure and shearing force. If the elasticity of the cover is too limited, the pressure-reducing capacity of the air-fluidized bed is decreased. The cover is permeable to bodily fluid, by which means the bodily fluids can simply pass into the tub with the silicone granules.
The “low-air–loss” systems consist, just like the air-fluidized bed, of a pump and a mattress (Brienza & Geyer, 2000). The mattress is made out of various compartments surrounded by an air-permeable cover. A continuous stream of warmed air is blown through the compartments, which is necessary to compensate for any loss of air through the cover. The patient is immersed into the mattress, thus enlarging the contact surface. This can be described as the “hovercraft-effect.”Just like air-fluidized beds, the magnitude of pressure and shearing force is reduced. The watertight cover is (micro)-permeable to air. The less elastic the cover, the more the pressure-reducing capacity of the mattress is diminished.
In the sitting position, pressure is very great at the contact surface (the bottom) (Bale, Price, Rees-Matthews, & Harding,2001; Garber, Krouskop, & Carter, 1978; Souther, Carr, & Vistnes, 1974; Sprigle, Chung, & Brubaker, 1990; Vandewalle, 1994). To lessen pressure in the sitting position, antipressure ulcer cushions are used to distribute the existent pressure, as evenly as possible, over a large contact surface (a larger surface than when no cushion is used). In this way the tissue at pressure points is less distorted (Kahmann, 1991). The use of cushions is not enough to prevent pressure ulcers. They must be combined with a painstaking observation of the skin and changes of position.
There are several types of cushions available. Based on interface pressure measurements and clinical trials, air cushions reduce pressure better than foam, gel, gel and foam, hollow-fiber, water cushions, or sheepskin (Defloor & Grypdonck, 2000; Shechtman, Hanson, Garrett, & Dunn, 2001; Yuen & Garrett, 2001) in the upright, lolling, or slumped-in-the-chair sitting positions (Defloor & Grypdonck, 1999). With thin air cushions, however, a “bottoming-out” effect (see Figure.8) occurs more quickly than with thick air cushions. The patient is then no longer supported by the cushion, but is resting on the underlying surface. Because of this there is high maximumcontact pressure (Defloor & Grypdonck, 1999, 2000; Krouskop, Williams, Noble, & Brown, 1986).
The pressure-reducing capability of viscoelastic foam cushions is, for uprightsitting persons, comparable with that of air cushions (Apatsidis, Solomonidis, & Michael, 2002; Defloor & Grypdonck, 2000; Rosenthal et al., 1996). In a slumped or lolling sitting position, the pressure-reducing capability of the viscoelastic foam cushions is less beneficial than that of air cushions (Defloor & Grypdonck, 1999). Gel and water cushions have either no effect or a limited one (Bar, 1991; Defloor & Grypdonck, 1999, 2000; Souther et al., 1974).
Decrease of the Duration of Pressure
Changing position means placing someone into a different position, in which all the points on which the body is supported (the pressure points) are changed. Changing position is only useful if this process is strictly applied, day and night, 7 days a week. The interval between position changes may never be longer than 4 hours if a patient is lying on a pressure-reducing mattress and 2 hours if this is not the case (Defloor, Clark, et al., 2005). Changing position also needs to occur during sitting periods and then with an even greater frequency than while the critically ill older adult is lying down (Panel for the Prediction and Prevention of Pressure Ulcers in Adults, 1992). Although it is recommended that a position is changed for someone lying on a nonpressure-reducing mattress every 2 hours, changing position should occur more frequently, for example every hour, while the patient is sitting. The use of pressurereducing cushions will allow patients to have their position changed less frequently.
Figure·8 Bottoming-out effect.
The aim of alternating systems is to decrease the length of time that the tissue is compressed by pressure, by alternating the load to various pressure points of the body. The cells/compartments of the mattress are alternately slowly inflated and slowly deflated or pumped out. Some alternating systems can be placed directly on the bedframe (mattress-replacing systems) or are integrated into the bed. Others need to be placed on top of the mattress (lay-on systems). Both systems are equally effective (Nixon et al., 2006). Alternating systems are useful for pressure-ulcer prevention (Cullum, McInnes, Beller-Syer, & Legood, 2006). Patients who lie on an alternating mattress do not need to have their positions changed (Vanderwee, Grypdonck, & Defloor, 2005). Heel pressure ulcers remain a problem, however. Even on alternating mattresses, a cushion has to be placed under the lower legs so that the heels are not supported on the mattress (floating heels), otherwise many patients develop heel pressure ulcers (Vanderwee et al., 2005).
Measures Aimed at Shearing Force
On lifting up a slumped patient, the risk is great that traction will be exerted on the skin and the underlying tissues at the sacrum. The tissue gets folded over or is subjected to shearing force (certainly if patients are dragged and not lifted). Any raising action, even sideways tilting (or lifting), can help to ensure that both the skin and underlying tissues are no longer subject to shearing force. Turning or changing the sheets of patients can help to prevent shearing force too (Goode & Allman, 1989). Correct positioning of the sitting attitude, to prevent slumping in the chair or tilting sideways, will greatly reduce shearing force and thus the risk of decubitus.
Measures Aimed at Tissue Tolerance
Measures aimed at tissue tolerance have only a limited support function and are insufficiently robust to prevent decubitus. The most important measures aimed at tissue tolerance are nourishment interventions. Pressure ulcers are more frequently observed in patients in a poor nutritional state. It is not known if a causal link exists between nutrition and the origination of decubitus. Optimizing the nutritional situation of risk patients can be an element of prevention policy (EPUAP, 2003). It is to be expected that the effect will be to postpone the occurrence of decubitus forming.
Pressure Ulcer Treatment
Ideally, pressure ulcers should be prevented, however, this is not always possible. It is therefore important to have effective treatment strategies that promote healing. As with any wound, such strategies need to consider both the patient and the wound. Keast, Parslow, Houghton, Norton, and Fraser (2006) suggest that this can be usefully addressed by:
- Identifying and treating the cause of the pressure ulcer
- Addressing patient-centred concerns
- Providing local wound care
- Providing organizational support.
Identify and Treat the Cause of the Pressure Ulcer
A basic principle of pressure ulcer management is to identify both the patient factors and the circumstances that resulted in the formation of the ulcer and, wherever possible, remove the cause. Healey (2006) suggests that a root-cause-analysis approach can be useful to gather and map information, identify and analyze the problems and to develop solutions to deal with the pressure ulcer. In the acutely ill elderly patient it is important to recognize that tissue resilience is generally reduced as a result of muscle wasting and loss of skin elasticity with aging (Dealey, 2005) and the added impact of acute illness can have major consequences. A full assessment of the patient will identify specific factors, for example, immobility, that have contributed to formation of the pressure ulcer. A common example is that of an elderly person falling at home and lying undetected for many hours, thus resulting in prolonged pressure. This may be exacerbated by incontinence, dehydration, and hypothermia. Another cause of immobility may be major surgery lasting many hours, resulting in prolonged pressure over bony prominences. In both these examples, pressure ulcers developed as a result of a critical incident. However, some patients may have very limited mobility and then develop an acute illness, increasing their existing vulnerability to pressure-ulcer development. Once the assessment has identified the factors relating to the pressure-ulcer development, a plan should be developed to alleviate them, where possible.
Most acutely ill are bedfast for the majority of the time and they may have limited ability to move within the bed. The management plan should include a strategy for pressure redistribution by repositioning the patient and the use of specialized mattresses and beds. As discussed earlier, the use of the 30° tilt position is useful, particularly so for potentially unstable patients as it requires little movement to get the patient into position. However, patients with breathing difficulties are likely to have difficulty remaining in this position (Young, 2004).
The use of dynamic-pressure-redistribution systems is common for critically ill patients as the majority are deemed to be at high risk of pressure-ulcer development. However, there is insufficient evidence to determine the most appropriate system to promote healing (National Institute for Health and Clinical Excellence, 2005). A pragmatic approach is taken in the Registered Nurses Association of Ontario (RNAO) guidelines (2007), which suggest that selection of equipment should be based on the overall goals of treatment, bed mobility, ease of use, and so on. It is important to note that the guidelines stress the need for ongoing evaluation of patient needs, rates of healing, and monitoring of other bony prominences for incipient pressure ulcers (RNAO). If a patient who previously had a prevention plan in place develops a pressure ulcer, then that plan should be deemed inadequate and must be reviewed. This may include upgrading the pressure-redistribution device in use to a more sophisticated system. For the critically ill elderly patient a continuous low-pressure system (low air loss or air-fluidized) may well be the most appropriate. Care should be taken to ensure adequate pressure relief for the heels as not all mattresses or beds provide this pressure relief adequately (RNAO).
Poor Nutritional Status and Dehydration
The role of nutrition in the development and healing of pressure ulcers is not absolutely clear. A systematic review of the literature found enteral nutritional support could significantly reduce the risk of pressure ulcers and may promote their healing (Stratton et al., 2005). A randomized study published after the review found improved pressure ulcer healing in a long-term-care facility in elderly patients who had received a protein supplement in addition to standard diet (Lee, Posthauer, Dorner, Redovian, &Maloney, 2006). Bergstrom et al. (2005) undertook a 12-week observational study of elderly patients with pressure ulcers and found that adequate nutritional support for those with stage-3 and stage-4 ulcers (NPUAP staging) was a strong predictor of healing.
An observational study of acutely ill patients with and without wounds who were being tube-fed showed that patients with wounds generally require more protein than those without wounds and that many failed to receive enough protein to meet their needs (Pompeo, 2007). Alix et al. (2007) found that the energy intake of acutely ill elderly patients was low and suggested that 24 to 30 kcal/kg body weight/day would be appropriate and possibly should be higher for those with a low body mass index. Part of the overall assessment of the patient should include a nutritional assessment and identification of any deficits. Loss of fluids and poor intake can also result in dehydration. Advice from a dietician and/or nutrition team can assist in establishing an appropriate regime relevant for the patient’s condition. For patients with severe pressure ulcers (grades 3 and 4) the multidisciplinary team should consider their basal energy expenditure and pay particular attention to the increased fluid loss through such wounds (EPUAP, 2003).
Incontinence of either urine or feces poses a challenge when managing pressure ulcers on the sacrum or buttocks as there is considerable likelihood of the ulcer becoming contaminated. There is also the risk of further skin breakdown as moist skin is more susceptible to friction and shearing forces (Keast et al., 2006). Barrier creams are widely used to protect the skin from incontinence-associated dermatitis (Gray, 2007), but they can interfere with the adherence of dressings over an ulcer. Beitz (2006) has reviewed the management of fecal incontinence in acutely and critically ill patients and provides a range of practical solutions, which are summarized in Table. 2. However, she also stresses the importance of identifying the causes of diarrhea and making dietary changes before using other methods such as pharmacotherapy.
Poor Tissue Perfusion
Poor tissue perfusion is common in the critically ill (Webster, 1999) and the focus of care is to ensure an adequate blood supply to the vital organs, often at the expense of the peripheral blood supply, especially to the lower limbs. Potentially, this may be an issue for the older patient, as one in five suffer from some degree of peripheral arterial disease (Meijer et al., 1998). The two factors combined result in a lower than normal capillary closing pressure at the periphery and can result in the development of heel ulcers. Although it may not be possible to address either of these issues when treating pressure ulcers on the heel, it is important to alleviate the pressure to promote healing.
Any assessment should identify factors of importance to the patient, including pain, quality of life, and psychosocial issues.
The symptom of pain related to pressure ulcers can be seen as an emerging clinical issue (Girouard, Harrison, & VanDenKerfof, 2008). Several qualitative studies have identified pain as a major factor in patients’ experiences of pressure ulcers (Hopkins et al., 2006; Langemo et al., 2000; Spilsbury et al., 2007). Szor and Bourguignon (1999) found that 87% of the 32 patients with pressure ulcers whom they studied experienced pain at dressing change and 84% had pain at rest. Gu ¨ nes (2008) used the McGill Pain Questionnaire and the Faces Rating Scale—Revised (FRS-R) to assess the pain of 47 patients with pressure ulcers of stages 2 to 4 (NPUAP classification). Forty-four (94.6%) patients complained of pain, but the severity of the pain increased with the severity of the ulcer. The study also found that there was a high correlation between the pain scales, indicating that the FRS-R could be of use for patients unable to verbalize their level of distress. This type of pain-assessment scale is of particular relevance to critically ill patients who may be unable to communicate verbally for a variety of reasons. Several pain-assessment tools have been developed for use in the critical care unit, however, a review by Li, Puntillo, and Miaskowski (2008) suggest that although some have good validity and reliability, they have not been adequately tested to determine which should come into standard use. Ahlers et al. (2007) warn that observer-based assessment often underestimates the level of pain suffered. In patients unable to communicate verbally it is a challenge to identify the causes of pain and to differentiate pain specific to the pressure ulcer. However, whatever the cause of the pain, adequate analgesia should be given and its effectiveness monitored. Management of pain related to dressing change will be discussed later.
Quality of Life and Psychosocial Issues
There is no doubt that pressure ulcers affect the quality of life of the sufferer both emotionally and socially (Hopkins et al., 2006; Spilsbury et al., 2007). However, for critically ill patients with pressure ulcers, their illness generally has a much greater impact during the acute stage. Once this phase passes then the situation may change and the pressure ulcer will be seen as an impediment to recovery (Hopkins et al., 2006; Spilsbury et al., 2007).
Local Wound Care
Assessing the Wound
Accurate assessment is the cornerstone of any treatment plan. When assessing a pressure ulcer the following needs to be taken into consideration:
- Wound bed appearance
- Presence of undermining
- Surrounding skin
Grading / Staging
Grading of pressure ulcers has been discussed. Consideration of the severity of a pressure ulcer should be a factor in selecting a suitable pressure-redistributing device.
Wound Bed Appearance
The terms commonly used to describe the wound bed are necrotic, infected, sloughy, granulating, or epithelialzing (Dealey, 2005).
Necrotic Tissue. Necrotic tissue presents as a hard black eschar and as it starts to debride it becomes a grey/black slough as shown in Figure.5, stage 4 pressure ulcer. There is no exudate with the eschar, but as the necrotic tissue softens and starts to debride there is an offensive exudate, which can become quite heavy.
Infected Wounds. Infected wounds of critically ill patients may be particularly vulnerable to infection and, depending on concomitant disease processes, may have reduced signs of infection (Gardener, Franz, & Doebelling, 2001). The early signs of a wound infection are often increased pain and heavier exudates, which may have an offensive odor. The color and smell of the exudate will vary depending on the bacteria infecting the wound.
Sloughy Tissue. Sloughy tissue is white or yellow in color and may present as patchy areas on the wound surface. Provided a moist environment is maintained on the wound surface, the macrophages will gradually remove slough from the wound and it will disappear as healing progresses (Dealey, 2005).
Granulation Tissue. Granulation tissue has a red granular appearance and will gradually fill any wound cavities. It is highly vascularized and easily damaged.
Epithelial Tissue. Once the wound bed is filled with granulation tissue, epithelial cells on the wound margin will start to proliferate and cover the wound surface.
Presence of Undermining
Undermining of the wound edges is commonly seen in pressure ulcers once they are debrided. This can pose an additional challenge to achieving healing as it means that the wound margins are fragile and vulnerable to further breakdown.
The quantity of exudate will, in part, be determined by the size of the pressure ulcer as well as the type of tissue present in the wound bed (World Union of Wound Healing Societies, 2007). Assessment should include identifying the color, consistency, and odor as well as the quantity. The discarded dressing can provide useful information about the quantity and color of exudate, but there are no validated tools for measuring exudate. One pragmatic proposal by Falanga (2000) is to score the exudate level as shown in Table.3.
A Scoring System for Wound Exudate
Dressings last at least a week
Dressings changed every 2–3 days
Dressings changed at least daily
Wound margins can provide further useful information about exudate levels. For example, the presence of maceration could indicate a heavy level of exudate that is being inadequately managed by the existing dressing regime. Erythema may indicate the presence of infection, but it could also be an early sign of further pressure damage.
As discussed earlier, pain is a major factor for pressure ulcers. Dressing change may exacerbate already existing pain and assessment should include any increase in pain at this time (Briggs & Torra i Bou, 2002). Pain may be caused by all stages of the dressing change: removal of the old dressing, cleansing of the wound, and even dressing application.
Maintaining a record of the size of an ulcer makes it possible to monitor healing progress. There are various methods for measuring a wound, all of which have limitations (Dealey, 2005). The simplest method is to measure the greatest length and the greatest width, ensuring that the second measurement is perpendicular to the first. For wounds with a cavity, the greatest depth should also be recorded. It is also useful to make a simple sketch of the wound shape and indicate the measurement points. These types of measurements are of limited value unless used with the full assessment described previously. Dealey suggests that chronic wounds should be measured every 2 to 4 weeks.
Providing Organizational Support
The principles of wound bed preparation (WBP) provide some useful guidance for the aims of treatment (Shultz et al., 2003):
- Debridement of necrotic tissue,
- Management of exudates,
- Resolution of bacterial imbalance,
- Undermined epithelial edge.
A comprehensive assessment will identify the specific requirements of an ulcer and guide the health care professional to an appropriate plan of care for the individual patient. It should also be noted that healing may not be the goal of care for the terminally ill and treatment should be modified to ensure patient comfort and dignity (RNAO, 2007).
Debridement of Necrotic Tissue
There are a number of ways of achieving debridement, but not all are suitable for every wound. Sharp debridement is the fastest method, but it should only be undertaken by a practitioner who has been especially trained to undertake the procedure (RNAO, 2007). It can be painful for the patient and analgesia may be required.
Biosurgery or larval therapy involves the use of sterile maggots from the fly Lucilia sericata to break down necrotic tissue and then ingest it (Thomas, 2001). This process is not effective on hard necrotic eschar. Although very popular in the United Kingdom, it is used less widely elsewhere.
Enzymatic preparations can be used to separate necrotic tissue by cleaving through the collagen holding it to the wound bed (Douglass, 2003). Autolytic debridement is achieved by dressings maintaining a moist environment at the wound/dressing interface thus enabling macrophages to phagocytoze the necrotic tissue. Examples of suitable dressings are hydrogels and hydrocolloids and also alginates if there is already moisture in the wound bed (Dealey, 2005).
Management of Exudate
Determining a strategy for exudate management depends on whether the goal is to increase, maintain, or reduce the level of wound moisture (World Union of Wound Healing Societies, 2007). Management of heavy exudate can be challenging for the nurse and failure to contain exudate is very distressing for the patient. It may be necessary to use a more absorbent dressing, such as an alginate or an absorbent foam, or to increase the frequency of dressing change. If more moisture is required the dressing choice should be one that donates moisture to the wound, such as a hydrogel.
Resolution of Bacterial Imbalance
Infected pressure ulcers may result in complications such as bacteremias or osteomylitis and can be fatal. Management can be complex, particularly in the critically ill patient. The European Wound Management Association (EWMA) has produced a useful position document on the subject that can provide guidance to the practitioner (EWMA, 2006). Topical antimicrobials, such as cadexomer iodine or silver, in a variety of formats are commonly used and can be effective, but there is no clear evidence of the most effective dressing to use on infected pressure ulcers (Moore & Romanelli, 2006). Systemic antibiotics may also be required, especially for the immunocompromised or if cellulitis, bacteraemia or osteomylitis is present (Moore & Romanelli).
The aim of treatment is to achieve a clean granulating wound with a healthy wound margin and clear signs of epithelialization. In the vast majority of pressure ulcers if the cause is identified and removed where possible, adequate pressure relief is provided, adequate nutrition is provided, and the wound bed effectively prepared, this aim will be achieved. The goal should then be to protect the wound until healing is completed.
Pain at Dressing Change
Factors that cause or increase pain will have been identified at assessment and allow appropriate strategies to be developed for the individual. Strategies could include provision of analgesia prior to dressing change; selection of a dressing that is easy to remove, such as the silicone dressings; select a dressing that can remain in place for several days to reduce the frequency of dressing change (Briggs & Torra i Bou, 2002). Two small studies have also considered the effect of combining diamorphine with a hydrogel for appication to painful pressure ulcers of terminally ill patients (Abbas, 2004; Flock, 2003). Both studies showed an improvement in pain control, but further research is required into this mode of application.
General Comments on Dressing Selection
There is a very broad range of wound-management products available but limited evidence to guide appropriate selection. A systematic review by Bouza, Saz, Munoz, and Amate (2005) found that although there was evidence to show that hydrocolloid dressings were more effective than saline-soaked gauze in healing pressure ulcers, there was insufficient evidence to determine the effectiveness of other dressing types because many of the studies were too small and used poor methodologies.
For the most part pressure ulcers can be prevented provided that effective preventive measures are taken early. On admission to the emergency ward or intensive care unit, pressure-ulcer risk should be assessed and prevention—if needed—should be started. To determine the risk, risk scales can be used in combination with clinical expertise. On the appearance of pressure-related nonblanchable erythema, preventative measures need to be started immediately.
The most effective measures focus on pressure reduction and pressure-point variation. Although older intensive care patients are often high-risk patients, adequate prevention can decrease the pressure-ulcer incidence significantly, resulting in less pain and discomfort, a shorter length of stay in the hospital, and decreased costs.
Determination of an adequate preventive approach is not easy and must be adapted to suit the needs of each patient individually. Or as George Bernard Shaw would say: “The golden rule is that there is no golden rule.” Finding the best solution is, not surprisingly, a creative nursing task.
Pressure-Ulcer–Related Web Sites
· European Pressure Ulcer Advisory Panel: www.epuap.org
· National Institute for Health and Clinical Excellence (Guidelines United Kingdom): www.nice.org.uk
· (American) National Pressure Ulcer Advisory Panel: www.npuap.org
· Pressure Ulcer Guideline Project of the EPUAP and NPUAP: www.pressureulcerguidelines.org
· Pressure ulcer classification (Ghent University): www.puclas.ugent.be
· Scottish Intercollegiate Guidelines Network (Scottish Guidelines): www.sign.ac.uk
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