Is Bed Rest An Effective Treatment Modality for Pressure Ulcers?
Look at the patient lying long in bed. What a pathetic picture he makes. The blood clotting in his veins, the lime draining from his bones, the scybola stacking up in his colon, the flesh rotting from his seat, the urine leaking from his distended bladder, and the spirit evaporating from his soul. — Dr. Richard Asher, British Medical Journal, 1947
Since Dr. Asher recorded his observations,1 many studies have documented the impact of bed rest. In article after article, the reader is cautioned to heed the severe complications of bed rest as a treatment modality. Physical complications such as contractures, muscle atrophy, osteoporosis, pathologic fractures, urinary tract infections, decreased cardiac reserve, decreased stroke volume, resting and post-exercise tachycardia, orthostatic hypotension, pulmonary embolism, deep venous thrombosis, pneumonia, anorexia, constipation, and bowel impaction are topics of particular focus.1-7 However, the complications of bed rest are not only physical; psychological complications have been documented as well.1-3,5-21 Despite this, bed rest is often prescribed as a treatment modality for pressure ulcers.
One article states, “If bed rest is to be regarded as a treatment, it must be subject to the same assessment as any other.”22 Considering the severe complications of bed rest, its efficacy must be clearly established. If the efficacy of bed rest cannot be proven, alternatives to its use must be explored to prevent the complications of this treatment modality and improve client outcomes.
The Case for Using Bed Rest
The Agency for Health Care Policy and Research (AHCPR) developed guidelines for the prevention and treatment of pressure ulcers.23 These guidelines were created by a panel of experts who conducted extensive literature searches and critical reviews. Peer and pilot reviews also were conducted. One of the guideline recommendations states, “A patient who has a pressure ulcer on a sitting surface should avoid sitting. If pressure on the ulcer can be relieved, limited sitting may be allowed (strength of evidence = C).”23 Interestingly, this recommendation is similar to the statement in a guideline updated 10 years later by the Registered Nurses Association of Ontario.24 In the discussion of this recommendation, the AHCPR document states, “Interface pressure between the ischial tuberosities and seating surfaces is high and must be relieved frequently to prevent soft tissue damage.”23 This statement referenced a study that involved healthy children and adults, patients with cerebral palsy, and paralytic patients that quantitatively mapped pressure distribution while sitting.25 In this study, interface pressure was measured without a pressure-reducing cushion, with feet unsupported and hands lightly supported in front of the chest or abdomen. Each of these factors would cause an increase in seating interface pressures, and as a result, the high interface pressure scores are not unexpected. Supporting the feet would allow part of the weight borne by the thighs to shift anteriorly to the feet and part to shift posteriorly to the buttocks.25 The sitting position studied is not typical of clients using mobility devices. Most patients use some type of cushion — often pressure-reducing and usually with footrests — to achieve better weight distribution. Patients who are able to actively shift laterally can redistribute pressure, lift off the cushion, bend forward, and the like. Such dynamic position change also impacts the pressure distribution over time.26 Even slight body movements (eg, leaning forward or side-to-side) performed while seated offer adequate pressure relief.27 Considering the significant differences in the posture evaluated and the typical posture and equipment used by people with disabilities, the findings of this study must be applied with caution.
To further support the AHCPR and RNAO recommendations to avoid sitting, reference is made to an article28 that includes the following recommendation: Because patients are likely to experience long periods of unrelieved pressure, they should sit only when pressure over the pressure ulcer can be relieved.23 Researchers developed the Timer-Logger-Communicator (TLC), a device that provides automatic direct measurement of “lift-off” behavior.28 This particular study focused on the collection and clinical use of data for evaluating the effectiveness of client education. Correlating the “lift off” behavior with pressure ulcers was not the primary focus of the study. One subject in the study developed a pressure ulcer after a prolonged episode of sitting; however, this patient did not develop a sore after similar previous episodes. The authors concluded that although a single episode of prolonged sitting, such as the one they described, may be necessary for a sore to form, it is not always cause enough.28 The authors also noticed that subjects routinely exceeded the 20-minute maximum sitting time without apparent skin breakdown. This study seems to suggest that patients with spinal cord injuries could tolerate sitting in their chairs without apparent skin breakdown even when not engaging in “lift off” behavior as often as recommended.
Clinically and sensibly, one would think increasing the surface area by lying down should reduce pressure and lead to healing of pressure ulcers. To date, however, no randomized controlled trial has conclusively shown that bed rest effectively manages pressure ulcers. Hardy et al29 state that “given the wide range of surface pressures that can impede capillary flow, only a measurement of zero interface pressure, or complete pressure relief can prevent tissue ischemia.” This comment does not appear to be supported by the study conducted by Merbitz et al,28 who found that clients were able to sit with relatively high pressure interface measurements without developing pressure ulcers. This may be due to the fact that only non-uniform pressure and variances in pressure gradients between adjacent tissue areas will create distortion; thus, increasing the potential for pressure damage.27
The Case Against the Use of Bed Rest
The impact and complications of bed rest have been topics of a number of studies over the years. The majority of the studies18,30-33 conducted during the past 10 years involved pregnant women or were performed by the National Aeronautics and Space Administration (NASA) as a model for weightlessness in space. Regardless of the population studied, the complications documented are remarkably similar and would likely apply to other populations, such as patients confined to bed to treat pressure ulcers.
Bed rest as a treatment was evaluated by Allen et al,22 who reviewed reports of 39 trials of bed rest for 15 different medical conditions and procedures. These medical conditions/procedures included: pressure ulcers, rheumatoid arthritis, proteinuric hypertension during pregnancy, spontaneous labor, acute low back pain, uncomplicated myocardial infarction, cardiac catheterization, and lumbar punctures. In the 24 trials reviewed regarding medical procedure outcomes, outcomes did not significantly improve and eight significantly worsened.22 In addition, of the 15 trials investigating bed rest as a treatment for medical conditions, including pressure ulcers, it was found that outcomes did not significantly improve, nine significantly worsened, and no evidence that bed rest as a treatment has any significant beneficial effect was presented.22
Some medical practitioners have slowly moved away from bed rest. For example, bed rest was routinely prescribed for clients after a myocardial infarction. In 1938, the effectiveness of this treatment was questioned as more clients were dying from pulmonary infarction, pneumonia, and other bed-rest related complications than were dying of cardiac complications during the 2 months of forced bed rest. Although it was recommended in 1944 to decrease the amount of bed rest to 2 weeks, at least 4 weeks was commonly prescribed. Now, common practice is bed rest for 12 hours only.22 This change to evidence-based practice took nearly 60 years. Because ideas about bed rest seem so embedded, changing medical practice has been slow despite evidence of ineffectiveness.22
Onset of complications. In the studies reviewed, physical and psychosocial impacts of bed rest manifested quickly — even in healthy test subjects. Within 6 to 10 days, bed rest and immobilization have been found to complicate the clinical condition8 and some studies indicate that these complications occur even more rapidly. Within 24 hours of bed rest, many organ systems are affected by pathophysiological changes that, if allowed to continue, may cause new illness and deconditioning, both of which can impair function.6 In addition, the realm of bed rest bears many similarities to aging that compound its effects.7
Hospitalization combined with bed rest may produce additional complications, such as enforced immobilization, reduced plasma volume, and sensory deprivation.3 When young persons were placed in a simulated hospital room, 29% developed subjective sensory distortions after 2¾ hours, leading researchers to ponder the effect of bed rest on the elderly, on the debilitated, and on the truly “isolated” patient confined to bed.11 In addition, the effects were found to persist, even when subjects resumed normal activity, for a period equal to the time of confinement.16
Cognitive/psychosocial complications. Decreased sensory input, a reduction of kinesthetic and proprioceptive stimulation, can produce intellectual and perceptual disorders.3,20 A substantial decrease in the central nervous system content of the neurotransmitters dopamine, norepinephrine, and serotonin occurs both in aging and after inactivity.12
Affective changes. Depression is one of the primary effects of bed rest. Bed rest changes the person from being a productive member of society, with roles in the community as well as within a family, to a person dependent on others for basic physical and social needs. Immobility-related dependency may contribute to anxiety, hostility, embarrassment, and helplessness.34 In a study18 of eight airmen ages 18 to 20 years who were placed on bed rest to better understand the impact of weightlessness in space, four continued to exercise while the others did not. Before the study, the airmen thought the bed rest phase would be “nothing,” “simple,” and a lark, but as that phase progressed, they expressed reservations about their ability to tolerate a prolonged period in bed. A number of psychological and physical tests, including the Multiple Affect Adjective Checklist (MAACL) and the Measurement of Depression Scale (SDS), were administered twice a week for the duration of the study. Higher scores on the MAACL indicate increased feelings of anxiety, depression, and hostility. Higher scores on the SDS indicate increased feelings of depression. Scores on the MAACL and SDS scales rose in both the active and inactive group, but the non-exercise group had significantly higher scores than the exercise group. These results also were observed by the researchers — specifically, the non-exercise group expressed greater hostility, anxiety, and depression.18 In addition, at the end of the study, although a return to almost base line values for the hostility and anxiety scales of the MAACL occurred, the SDS and depression scales of the MAACL remained somewhat elevated.18 This indicates that the depression component continued to be a factor even after the bed rest phase was over.
Another psychological impact of bed rest can be “learned helplessness.” Patients in bed are expected to act sick — the “good” patient (ie, docile and compliant) takes medications and follows professional orders without asking questions.12 Caregivers tend to reinforce this learned helplessness by reacting negatively to “uncooperative” patients, as well as by controlling various aspects of the client’s life such as social contacts, money, and appointments. It is no wonder many patients have trouble resuming independence and decision making after prolonged bed rest.12
Intellectual/perceptual changes. Studies show that bed rest impacts perception and certain intellectual functions. In one study,11 180 healthy volunteers between the ages of 18 and 35 years were confined to bed rest in a simulated hospital environment for 2¾ hours. The subjects were allowed to move freely in bed, but remained awake for the duration of the study. At least 20% of the 180 subjects experienced sensory distortions. The symptoms exhibited were disturbing to a number of participants and so clearly evident that all practitioners should be aware of their probable occurrence among people who are bedridden.
In another study,20 22 healthy male university students were confined to bed for a period of 1 week. They were maintained in a supine posture for the majority of the time with brief periods where they could get out of bed. During their time in bed, they were exposed to as normal an environment as possible. Study participants were given two sets of tests,12 intellectual and five perceptual. The intellectual tests were administered before the experiment and at daily intervals during the bed rest period. The perceptual tests were administered before and after the bed rest period and electroencephalograms (EEGs) were obtained from 10 subjects. When test data were compared to a matched control group, researchers found that the mean intellectual test performance of study subjects during immobilization was worse than the controls on every test.20 In addition, color discrimination and reversible figures were significantly impaired on the perceptual tests.20 An analysis of the EEGs showed that occipital lobe frequencies decreased 0.56 cycles per second after the week of immobilization.20 Intellectual function and perception also were impaired in the eight airmen studied and during bed rest the participants seemed mentally more lethargic.18
Endurance. Interestingly, fatigue is a common complication of bed rest noted in the literature. A sense of fatigue and reduced patient motivation initiates a vicious cycle of greater inactivity (both as a contributing factor and as a result of further fatigue); thus, decreasing endurance levels.5
Physical complications. As early as 1947, Asher1 recognized and documented the hazards of bed rest. His intention was to “justify placing beds and graves in the same category and to increase the amount of dread with which beds are usually regarded.”1 He recognized that no part of the body is immune from the dangers of bed rest, a fact later confirmed by research.
Joints and muscles. One of the most commonly recognized complications of bed rest is weakness and muscle atrophy. Without the presence of voluntary contraction, muscle strength decreases by 5% per day.3 Not surprisingly, loss of strength with inactivity is greater in antigravity muscles than in other skeletal muscles.5 Joint contractures are also common for people confined to bed rest because inactivity rapidly contributes to muscle shortening and changes in periarticular and cartilaginous joint structure, which contribute to a tendency toward limited motion and contractures.3
Bones. Loss of bone density is common with bed rest. Loss of calcium from bones begins immediately after bed rest, and within a few days, increased urinary clearance of calcium can be detected.12 Exercise does not appear to reduce this effect; despite rigorous activity, astronauts suffer profound loss of bone mass in weightless environments.5
Urinary tract. Urinary tract infections also occur with people confined to bed rest. In a supine position, bladder emptying may be incomplete.2 The renal pelvis drains entirely by gravity and no gravitational emptying occurs in a recumbent patient, leading to stagnation in the calyces, predisposing patients to calculus formation and infection.2
Heart and circulatory system. As a direct result of bed rest/immobilization, plasma volume is lost.3 In addition, heart rate increases (generally to more than 80 beats/minute), most likely due to increased sympathetic nervous system activity.5 Because increased heart rate results in less time for diastolic filling and systolic ejection, the heart does not respond as capably to metabolic demands above the basal level.5 Also, length of bed rest and the frequency of deep vein thromboses are directly related.5
Lungs. The supine position affects the physical act of breathing because cephalad displacement of the diaphragm against the thorax results in decreased lung volumes.6 The supine position causes changes in both lung volumes and the mechanics of breathing that frequently cause atelectasis and oxygen desaturation, predisposing the patient to pneumonia.7 Signs of decreased oxygenation may include forgetfulness, irritability, and restlessness15 and may occur in tandem with the psychosocial complications noted previously, compounding the effect on the patient.
Gastrointestinal track. People on bed rest tend to lose their appetite and are at risk for becoming malnourished. Patients in the supine position may be predisposed to gastroesophageal reflux6 as well as constipation, which may occur because feces cannot be expelled if the patient experiences weakness or difficulty defecating into a bed pan.6 Good nutrition is required for wound healing; a decreased appetite may result in the wound taking longer to heal.
Moderating the Psychosocial/Cognitive Complications
Perhaps the first approach should be to limit the amount of bed rest. As bed rest is usually prescribed in an effort to decrease pressure over the wound, alternatives to managing pressure may decrease the amount of bed rest required. Recognizing that complications, albeit reversible, may occur and long periods of rehabilitation will be required because reconditioning takes longer than deconditioning, is important.3
Occupational therapy may help minimize the psychological/perceptual complications. Integrating meaningful tasks into an individual activity program can promote cognitive and motor recovery and enhance patient motivation to participate in an overall care plan.8 One simple way to decrease the impact of bed rest and isolation is to increase outside stimulation.12
Caregivers can help decrease complications by involving the patient in care decisions to decrease the incidence of “learned helplessness.” Also, taking the time to talk with patients about their concerns helps alleviate anxiety.
Bed Rest Alternative
When evidence of the serious complications of bed rest is combined with its lack of efficacy, finding alternatives to managing pressure ulcers becomes paramount. One alternative is to manage interface pressure throughout the patient’s Activities of Daily Living (ADL) (see Table 1).
When choosing a therapeutic support surface, the RNAO guideline suggests using a static surface in circumstances where the patient can assume a variety of positions without putting weight on a pressure ulcer or “bottoming out” (Strength of Evidence = B).35 A dynamic surface should be prescribed if 1) the patient cannot assume a variety of positions without bearing weight on a pressure ulcer, 2) the patient fully compresses the support surface or 3) the pressure ulcer does not show evidence of healing” (Strength of evidence = B).35 However, compelling evidence is lacking that one surface is better than others in terms of pressure.23,36 Table 2 outlines the factors to consider when choosing a therapeutic support surface for an individual client. Probably the most important factor to improve patient adherence is comfort. Assessment of all selection factors will help the clinician identify a therapeutic support surface that best meets client and caregiver needs.
Patient assessment. A thorough seating and mobility assessment will identify areas that need to be addressed for friction and shear reduction. This assessment should be global in nature and includes all surfaces, transfers, and environments. Seating and mobility assessments are usually conducted by an occupational or physical therapist. As with mattresses, a number of studies37-41 have been conducted to determine the “best” cushion; however, no conclusive evidence to recommend one particular cushion/seating and mobility system for every patient is available. Individual needs must be assessed and subsequent goals set to determine the most appropriate cushion/seating and mobility system for that patient. The general assessment domains for consideration are listed in Table 3. Of particular importance is the patient’s readiness to change. The client may need support and education to accept the need for change.
Product appropriateness. Once the therapist has completed the assessment and established the goals, the challenge is to match the findings with the available equipment (see Figure 1). The systematic evaluation of each component of the equipment prescription will ensure that the patient’s goals, as well as the need for pressure management, are met (see “Keys to Safer Sitting”).
“No one support surface is best for all people….the only true test of a support surface is how it works with the patient or client.”42 The selection of a surface/cushion should follow an evidence-based framework that includes experimental evidence (eg, pressure mapping if available, checking for redness, and the like); expert opinion; and patient preference. Although one ideal seating system that meets every client’s needs does not exist, some considerations may prove helpful when recommending either a wheelchair or an easy chair. These considerations include:
• Client comfort
• Client must like the chair (color, size, and the like)
• Seat-to-floor height facilitates transfers
• Seat cushion distributes pressure (no redness)
• When upright, the back should be close to (5 degrees or less) upright, unless the client has spinal deformities, to prevent shearing forces
• If available, chair should tilt before it reclines to reduce shearing (for easy chairs, powered is better than non-powered)
• Chair should be an appropriate fit for its environment (including space for use, size, color)
• Chair fabric is breathable and minimizes the impact of shearing
• Chair tilt feature accommodates the posture of individual
• The lift component of chair, if available, facilitates both sit-to-stand positions, and stand-to-sit positions.
Nutrition. Another component of the intervention process is ensuring adequate nutrition. If the patient is not adequately nourished, the wound may not heal. The nutritional screening assessment should encompass history and symptoms and include the following43:
• Assessment of total body weight. Evaluate the size and relative density of body protein to body fat. Severe malnutrition is a concern if the patient weighs less than 70% of the ideal body weight
• Assessment of lean body mass directly using a body composition analyzer or indirectly through anthropometric data
• Estimation of the patient’s ultimate total body protein status by evaluating humoral proteins (albumin, globulin, and circulating hormones). It may be necessary to draw blood if the chemistry screen is not available. If albumin <2.1g/dL, transferrin<100mg/dL, total protein<5.0g/dL, and total lymphocyte count is <800mm^3, severe deficiency exists
• Adjustment of diet to correct deficiencies
• Ensuring patient has assistance required to make changes
• Assessment of psychological state in cases where appetite may be suppressed by depression, anxiety, or other psychological reason
• Considering need for appetite-stimulating medications such as antidepressants (eg, amitriptylene), gastro-intestinal medications (eg, cisapride, domperidone or metoclopramide) or general agents (eg, cyproheptadine, clonidine) as appropriate
Protein intake requires a careful assessment when determining a treatment plan because protein is the key nutrient associated with pressure ulcer healing. Sufficient calories and essential vitamins also must be supplied; however, supertherapeutic replacement of specific nutrient factors has not been proven effective and may potentially be harmful.44
Ms. M is a 56-year-old woman with paraplegia secondary to a spinal tumor in 1992. She has a history of skin breakdown over her left ischial tuberosity; currently, she has a Stage III pressure ulcer at this location. Despite her adherence to bed rest orders over the past 3 months, the ulcer has not healed. The bed rest order is increasingly burdensome for her. She would like to resume her normal lifestyle and feels depressed.
Ms. M was assessed in the seating clinic. She was using a lightweight manual wheelchair with a gel cushion. She uses a sliding board transfer from her wheelchair to all other surfaces. As part of the assessment, a pressure mapping evaluation of her bed, commode, tub transfer bench, and wheelchair was completed. Her cushion was not providing adequate pressure distribution. In addition, when she was tired she did not lift herself high enough during transfers to clear the edge of the transfer board, which created additional trauma to the wound area. Although the pressure maps showed adequate pressure distribution on her current low-air-loss mattress, she found it extremely difficult to move in bed and transfer to her chair.
Seating interventions. Ms. M received a prescription for a power wheelchair with an air cushion. The power wheelchair enabled her to preserve her strength for transfers. Pressure maps of the air cushion indicated adequate pressure distribution. In addition, Ms. M initiated a weight shifting routine during which she would offload her buttocks every 20 minutes.
Mattress selection. Ms. M had the opportunity to try several mattresses and ultimately chose a static air overlay. She found she was able to move on this mattress and transfer more easily. Pressure mapping also indicated adequate pressure distribution.
These interventions allowed Ms. M to increase her wheelchair time to 8 hours per day. Her wound healed a month later. She is very happy to resume her normal routine and her outlook has improved.
Practitioners often express concern that medical and scientific studies are difficult to interpret for clinical use; however, in terms of the complications of bed rest, agreement between all existing sources is remarkable. Although illness severity may leave no choice except bed rest, the rest itself is rarely what is of benefit. Practically every organ and body system promptly and progressively deteriorates when it is inactive (see Table 4).2
In this time of focusing on best practices and patient outcomes, examining the practice of bed rest is appropriate. If effort were directed at conducting a randomized control trial to reevaluate the practice of bed rest, assuming that bed rest could speed the healing of pressure sores, the complications of this treatment are so well documented that this practice cannot be considered “safe.”
Alternatives to bed rest include optimizing the nutritional status of the client and managing pressure and shear throughout the client’s daily activities. Managing pressure and shearing forces outside of the bed may be one way to improve client outcomes and quality of life.