April 16, 2007

Pressure sores


Pressure sores (bedsores, decubitus ulcers) are areas of skin damage resulting from a lack of blood flow due to pressure.

Pressure sores can occur in people of any age who are bedridden, chairbound, or unable to reposition themselves. However, they frequently affect older people. Pressure sores usually develop below the waist, although they can occur anywhere on the body. They tend to occur over bony projections where pressure is concentrated, such as the lower back, heels, elbows, and hips. They may occur where pressure from a bed, wheelchair, cast, splint, or other hard object contacts and presses on the skin. Pressure sores may be painful and can be life threatening. They lengthen the time spent in hospitals or nursing homes and increase the cost of care.


The skin has a rich blood supply that delivers oxygen to all its layers. If that blood supply is cut off for more than 2 or 3 hours, the skin dies, beginning at its outer layer (the epidermis). The dead skin breaks down and forms an open sore or ulcer. Once the skin is broken, bacteria may enter the opening and cause an infection.

Pressure reduces blood flow to the skin. The intense pressure created by sitting in a chair or lying on a mattress cuts off blood flow over bony areas. Most people do not normally develop pressure sores because they constantly shift position without thinking, even when asleep. However, some people are incapable of normal movement and are therefore at high risk of developing pressure sores. This group includes people who are paralyzed, comatose, very weak, or restrained. Paralyzed and comatose people are at particular risk because they may be unable to sense discomfort or pain, signals that normally motivate people to move or to ask to be moved.

Traction also reduces blood flow to the skin and can lead to pressure sores. Traction occurs when the skin sticks to something, often bed linens. When the skin is pulled, the effect is much like pressure.

Friction can lead to pressure sores as well. Repeated irritation may wear away the top layers of skin. Such irritation may occur if a person scrapes the heels, elbows, or knees or wears poorly fitted shoes.

Skin moisture can lead to the development of pressure sores. Prolonged exposure to moisture—often perspiration, urine, or feces—weakens and damages the skin surface, making pressure sores more likely.

Inadequate nutrition increases the risk of developing pressure sores and slows the healing process of sores that do develop. Malnourished people lack the protective layer of fat that helps pad the skin and that keeps the blood vessels from being squeezed shut. People whose diets are deficient in protein, vitamin C, or zinc, which are essential for normal skin repair, are at increased risk as well.


For most people, pressure sores cause some pain and itching. However, in people whose senses are dulled, even severe, deep sores may be painless.

Pressure sores are categorized into four stages according to the severity of damage, from redness and inflammation (stage 1) to destruction of muscle, fat, and bone (stage 4).

Infection delays healing of shallow sores and can be life threatening in deeper sores. Infection can even penetrate the bone (osteomyelitis), requiring weeks of treatment with antibiotics. In the most severe cases, infection can spread into the bloodstream (sepsis).


Prevention is the best strategy for dealing with pressure sores. In most cases, pressure sores can be prevented by meticulous attention from all caregivers, including nurses, nurses' aides, and family members. Close daily inspection of a bedridden or chairbound person's skin can detect early redness or discoloration. Any sign of redness or discoloration is a signal that the person needs to be repositioned and kept from lying or sitting on the discolored area until it returns to normal.

Because shifting position is necessary to keep the blood flowing to the skin, oversedation should be avoided and activity encouraged. People who cannot move themselves should be repositioned every 2 hours—more often if possible. The skin must be kept clean and dry, because moisture increases the risk of developing pressure sores. Dry skin is less likely to stick to fabrics and cause traction.

Bony projections (such as heels and elbows) can be protected with soft materials, such as cotton or fluffy wool. Special beds, mattresses, and seat cushions can be used to reduce pressure in people who are wheelchair-bound or bedridden. These products can reduce pressure and offer extra relief. A doctor or nurse can recommend the most appropriate mattress surface or seat cushion. It is important to remember that none of these devices eliminate pressure completely or are a substitute for frequent repositioning.


Treating a pressure sore is much more difficult than preventing one. Adequate nutrition is important in helping pressure sores heal and in preventing new sores from forming. A well-balanced, high-protein diet is recommended as well as a daily high-potency vitamin and mineral supplement. Supplemental vitamin C and zinc may help with healing as well.

In the early stages, pressure sores usually heal by themselves once pressure is removed. When the skin is broken, a doctor or nurse will consider the location and condition of the pressure sore when recommending a dressing. Film (see-through) dressings help protect early-stage pressure sores and allow them to heal more quickly. Hydrocolloid (oxygen- and moisture-retaining) patches protect, keep the skin appropriately moist, and provide a healthy environment for deep sores. Other types of dressings may be used for deeper sores, those that ooze a lot of fluids, and those that are infected.

If the sore appears infected or oozes, rinsing with saline and wiping gently with a gauze pad is helpful. Sometimes stronger cleansing agents are used. A doctor may need to remove (debride) the dead material with a scalpel or with chemical agents.

Newer treatments for wound care include vacuum-assisted closure devices, which apply suction to a wound; growth factors, which are substances (usually proteins) that stimulate cells to grow; hyperbaric oxygen treatment, in which a person is placed in a chamber with oxygen at increased pressure and synthetic skin grafts.

Deep pressure sores are difficult to treat. Sometimes they require skin grafting, in which healthy skin is transplanted to the damaged area. This type of surgery is not always successful, however, especially for frail older people who are malnourished. Often, when infections develop deep within a sore, antibiotics are given. When bones beneath a sore become infected, the bone infection (osteomyelitis) is extremely difficult to cure and may spread through the bloodstream, requiring many weeks of treatment with an antibiotic

Adapted from: Merck & Co. Inc