Bed sores are breaks to the skin’s integrity, caused by insufficient blood circulation to affected tissues secondary to sustained pressure. Individuals at risk for developing bed sores are those whose primary diagnosis renders them immobile, the wheelchair bound, for example, or patients confined to a bed. Bed sores occur most often over bony areas like the shoulder blades, tailbone, the hips, the ankles, the heels, or the elbows.
When an individual remain in one position for too long, restricted blood flow can lead to decreased oxygenation to the skin over these body parts. The result? The affected tissues begin to die.
Bed sores are one of mankind’s oldest afflictions. They’ve been found in excavated Egyptian mummies and were first described in the scientific literature in the 18th century. Today between 3% and 10% of all hospitalized patients develop decubitus ulcers.
In nursing homes that figure hovers between 17% and 28%.
It’s been estimated that the treatment of bed sores cost the American healthcare industry over one billion dollars a year.
That is a remarkable figure when you consider the fact that most medical experts agree they can be prevented altogether by changing position every two to four hours
The term “bed sore” is something of a misnomer since outbreaks are not confined to the bedridden.
More properly the wounds are referred to as “decubitus ulcers” (from the Latin decumbere meaning “to lie down.”)
Occasionally they are also called “pressure ulcers” or “pressure sores.”
Symptoms of Bed Sores
Any person who remains in a single position for a length of time is at risk for developing skin breakdown. The National Pressure Ulcer Advisory Panel, a research and advocacy group, classifies pressure sores into four stages using the depth of the lesion as its criteria. (Note that not all pressure sores follow this progression.)
The affected area appears reddened and blanches to the touch. (In people with darker skin, the area will seem bluish or ashen.) The affected area may hurt or itch. The skin patch may feel warm and seem hard or spongy. When the pressure source is relieved, these symptoms generally disappear within 24 hours.
A lesion has appeared on the affected area that resembles a blister or an abrasion. It’s not deep – generally it involves the destruction of only the most superficial layer of skin although occasionally it reaches into the underlying dermis. Surrounding tissues may show some discoloration.
The lesion develops a crater-like appearance as the damage extends into the subcutaneous fatty tissues.
The lesion extends even more deeply, often affecting the fascia, the muscles, the tendons and sometimes even the bones. Wound drainage and foul odors may indicate the presence of secondary bacterial infections.
Some decubitus ulcers are so severe they cannot initially be staged: eschar (dead tissue) or other wound detritus obscures the mouth of the lesion, making it impossible to estimate its depth.
Diagnosis in the early stages is not always a simple matter. Caregivers need to familiarize themselves with the first signs of skin breakdown because as a decubitus ulcer penetrates into the deeper skin layers, the chances of complete healing decrease.
Causes of Bed Sores
Bed sores have a single, simple cause: uninterrupted pressure (in excess of the capillary refill reflex) to the affected area. In some cases, irreversible damage may begin to occur after as little as two hours of unrelieved pressure.
Pressure sores do not occur in most people. Ever sat still so long in one position that when you finally moved you ached? The same process is involved in the formation of decubitus ulcers. Eventually you did shift position; and for most people, even when they’re asleep, a complicated set of neuronal feedback mechanisms alert their bodies when it’s time to make a postural adjustment.
But people who are comatose, paralyzed, sedated, restrained or otherwise unable to move volitionally cannot move on their own. This is the population at risk for developing bed sores. For someone who cannot move, something as simple as a wrinkle in a bed sheet can begin the process of skin breakdown.
Pressure sores can also develop or be exacerbated as a result of friction when a body is rubbed or dragged across a surface, or when traction is applied to the skin.
Why do pressure sores occur? When pressure interrupts the skin’s capillary blood flow, it also interrupts the supply of oxygen brought to the skin by the blood in those capillaries. Without oxygen tissues begin to die, a process medical scientists call ischemia. The damaged tissues reddens as part of the inflammatory response when, in an effort to increase the blood supply, white blood cells release enzymes that dilate the capillaries. Vasodilatation causes the capillaries to leak, which leads to a build up of plasma fluids around the affected area responsible for the spongy or hard texture of the site.
Secondary bacterial infection is common with bed sores. Not only does infection compromise the healing of shallow sores, but should it spread into the bloodstream it can become life threatening. The actor Christopher Reeve died of sepsis secondary to a bed sore. Secondary bacterial infection can be diagnosed by the presence of pus and an unpleasant odor arising from the lesion site.
Bacterial infections can evince themselves as an acute and painful condition of adjacent connective tissues called cellulitis (which untreated can lead life-threatening complications like meningitis) or infections of the bone (osteomyelitis) and joints (infectious arthritis.)
Risk Factors For Developing Bed Sores
Anybody who is immobilized – even for a brief interval of time – is at risk for developing pressure sores. A number of factors increase susceptibility:
Two thirds of all decubitus ulcers occur in individuals who are over 70 years of age because the elderly tend to have thinner skin than younger individuals and are also more likely to suffer from malnutrition. The speed of healing in general decreases as people age.
Spinal Cord Injuries
Not only are spinal cord injuries immobilizing, they also interfere with the perception of pain and other kinds of discomfort. Since blood flow is decreased to the areas of the body beneath the break, healing occurs much more slowly. The annual incidence of bed sores among this population is estimated at between 5% and 8%, and some studies estimate their likelihood of developing a decubitus ulcer over the course of a lifetime to be as high as 85%.
Weight Loss and Malnutrition
Fat and muscle cushion bony prominences but people who are sick in bed or hospitalized for other reasons tend to lose fat and their muscles atrophy. Inadequate nutrition is a serious problem among the elderly in the United States, and the link between bed sores and malnutrition has been well documented. Dehydration also contributes to skin fragility.
Moisture generally contributes to skin breakdown, and the metabolic wastes in urine can be particularly damaging to fragile skin. Fecal incontinence greatly increases the risk of secondary bacterial infection.
The nicotine in tobacco impairs circulation leading to decreased levels of oxygen in the blood and far longer healing times for any type of injury.
Other Medical Conditions
Diabetes, chronic vascular diseases and other conditions that impair circulation increase the likelihood of skin breakdown. Muscle spasms and contractures put individuals suffering from spinal paralysis at risk for developing pressure sores from friction and shearing forces.
It’s been estimated that between 17% and 28% of all nursing home residents suffer from decubitus ulcers. There are many reasons for this: the population of these facilities tend to be either medically fragile or elderly. A study by Howard and Taylor found that the incidence of pressure sores in one nursing home in the southeastern United States varied by race and gender. If this is evidence of bias in caregiver decisions, that would be a disturbing trend indeed.
Slightly fewer than half a million hospitalized patients develop decubitus ulcers in a single year. One study of found that over 36% of 658 patients operated on for hip fractures went on to develop pressure sores within 32 days of their admission to a hospital. Decubitus ulcers are a leading factor in iatrogenic deaths among hospitalized populations, secondary only to adverse drug reactions.
The Braden Scale for Predicting Pressure Ulcer Risk – developed as part of a National Institute of Health proposal – is a tool designed to quantify the process of identifying vulnerable individuals. Using six weighted risk factors, the Braden Scale has proven to be a more reliable predictor of pressure ulcers than subjective assessment.
Bed Sore Prevention Tips
Bed sores are a classic example of the old adage that an ounce of prevention is worth a pound of cure: in the vast majority of cases, bed sores can be prevented by the simple expedients of frequent position shifts and a thorough, routine, daily inspection of the skin to identify potential trouble spots.
If incontinence is a factor, skin barriers like the new, polymer-based protective films should be used in addition to absorbent padding to protect the skin. Improved hydration will make skin less friable, while better nutrition (particularly through foods rich in protein, zinc and Vitamin C) will lead to increase the body’s ability to heal itself should breakdown occur.
If you are bedridden or immobilized, you will have to rely on the assistance of caregivers; the optimal interval for repositioning is once every two hours and in no event should you go longer than four hours without a postural readjustment.
Special care must be taken with bedridden patients so that pressure is not put on the hips, tailbone, ankles, shoulder blades or elbows. Individuals lying in bed on their side will optimally be positioned at a 30 degree angle (through use of a pillow under the small of the back) so that no weight is directly on the hip bones. Individuals lying on their backs in bed will use foam pads or pillows under their calves to lift their feet from the bed’s surface.
Bony prominences must be prevented from touching one another through the use of strategically placed pillows and foam padding. Raising the head of the bed more than 30 degrees increases the likelihood that you will slip out of a safe position and should therefore be avoided.
If you are bedridden for any length of time, consider a specialized, pressure-relieving mattress. Little known fact: the very first waterbed was invented in 1832 by the distinguished Scottish physician Dr. Neil Arnott as a means of preventing bed sores in invalids. This early model was pretty primitive, consisting of a bath covered with rubberized canvas on top of which bedding was placed. More sophisticated waterbeds are now a first line of defense against bedsores along with air, foam and gel mattresses.
Pressure-relief wheelchairs are designed to tilt in order to redistribute weight which makes sitting for long periods of time safer and more comfortable. If you do not have a pressure-relief chair and you can move independently, medical experts recommend realigning your weight every fifteen minutes or so. So-called “wheelchair pushups” – using your upper arms to lift your body off the seat – are a great way to relieve pressure if you have enough upper body strength.
If you cannot move independently, your caregiver will assist you in repositioning your body every fifteen minutes or so.
Just as bedridden individuals need pillows and cushions to redistribute their weight, so do the wheelchair bound. No body part susceptible to skin breakdown should ever be positioned directly up against a hard surface.
Routine Daily Skin Inspections
Checking the skin regularly for early signs of skin breakdown is a critical part of bed sore prevention. Stage I decubitus ulcers will often resolve completely within 24 hours after the pressure source is removed. The deeper the lesion however, the longer the healing time and even some Stage II pressure sores never completely heal.
In wheelchair bound individuals, skin breakdown is most likely to begin on the buttocks and tailbone, lower back, legs, heels and feet. Bedridden individuals need to look out for their your hips, spine and lower back, shoulder blades, elbows and heels. These areas of the body may be difficult to visualize even if you have some mobility and can use a mirror, so caregiver assistance is highly recommended here.
If inspection identifies a Stage I pressure sore, pressure to that area must immediately be removed. A protective dressing should be applied to the area after it’s gently washed with soap and water. On no account should a Stage I pressure sore ever be massaged in an attempt to increase circulation as this may lead to a reperfusion injury.
If inspection identifies a pressure sore that’s Stage II or higher, immediate medical attention is indicated.
Bed Sore Clinical Diagnosis and Tests
Bed sores are easily diagnosed by sight. Nurses and physicians use the lesion’s size and depth to develop a treatment plan. Even in cases where the pressure sore is not severe however, blood tests are often ordered at the time of diagnosis to provide insight into an individual’s overall health and nutritional status.
In Stage III and Stage IV pressure sores, further diagnostic tests may be indicated particularly in cases where infection has invaded the tissues. When a lesion does not respond to treatment, a physician may order a tissue biopsy to check for the presence of less common bacteria, fungi or even cancer cells.
Treatment Options for Bed Sores
Most Stage I and Stage II decubitus ulcers will heal on their own over time without surgical intervention. An effective treatment plan will include pressure reduction through frequent repositioning and the use of padding and support surfaces as well as proper cleansing of the affected area and a nutritional consultation. Stage I pressure sores rarely require wound dressings. The treatment of choice for Stage II pressure sores is wound dressings that contain topical antiseptics and antimicrobials. Oral antibiotics are used cautiously if at all due to the potential for producing antibiotic-resistant bacterial strains.
Stage III & Stage IV
Stage III and Stage IV decubitus ulcers may require more aggressive treatment. If infection exists, it must be tackled before surgical intervention is attempted. The presence of infection is often an indication of dead or necrotic tissue around the lesion site, and this must also be removed to decrease the chance of further infection.
Surgical debridement using a scalpel to remove dead tissue is quick but painful. Nonsurgical debridement techniques include autolytic debridement, a technique that uses high-pressure water sprays, and enzymatic debridement, where topical enzymes are applied to the affected areas. Another form of hydrotherapy involves the use of whirlpool baths to keep skin clean and wash away dead tissues.
The goal of surgical intervention is wound closure which may be accomplished through skin grafts, tissue flaps or some other means. Before a surgical intervention takes place, the lesion must be aggressively debrided. Wound closure makes hygiene protocols easier to implement, reduces the possibility of further infection, and raises the affected individual’s own morale. The procedure generally involves the use of tissue – either muscle or skin – harvested from other areas of the individual’s own body to reduce the chance of rejection.
The prognosis for early-stage pressure sores is good if the lesion is identified early enough although healing typically requires weeks. But even when a decubitus ulcer responds to treatment, the reoccurrence rate may be as high as 90% if underlying care issues such as immobility and nutrition are not aggressively addressed.