01:00 AM EDT on Sunday, August 22, 2004

CAUSE: Bedsores, also called pressure ulcers, generally form when a person is in a sitting or lying position for too long. Constant pressure decreases the skin's blood supply to that area. Unless this pressure is relieved, the tissue will soon show signs of injury. In addition, the skin can be damaged when the person is dragged or slid across bed sheets. These injuries are more likely to occur when the head of the bed is raised more than 30 degrees.

Bedsores are generally classified into four stages, depending on the severity of skin damage. The most common areas for bedsores are where bones are close to the skin, such as the hips, spine, buttocks, shoulder blades, elbows, heels, ankles and back of the head.

PREVENTION: Health care experts believe that at least 50 percent of bedsores can be prevented. These measures include:

- When in bed, turn or shift at least every two hours -- more often when sitting in a chair. Use pillows as needed to raise the person's arms, legs, buttocks and hips. Relieve pressure on the back with an egg-crate foam or water mattress.

- Control the factors that contribute to bedsores, such as sweating, incontinence, friction and shear. Either lift the person or have them use an overhead trapeze to briefly raise their body. Keep the bed free from crumbs and other small particles that can rub and irritate the skin. Use boots and elbow pads to reduce friction on heels and elbows.

- Wash the skin gently around the sore regularly with a mild soap and water.

- Avoid using irritating antiseptics, hydrogen peroxide, iodine solutions or other harsh chemicals to clean or disinfect the skin. Then pat the skin dry and apply a moisturizing skin lotion or cream.

- Encourage the person to eat a balanced diet that includes enough calories, protein, calcium, and zinc and vitamins C and E.

- Exercise increases blood flow and speeds healing. In many cases, even bedridden people can do stretches and isometric exercises.

PROGNOSIS: There is a good chance that a Stage 2 bedsore will heal within 1 to 6 weeks in a relatively healthy older person who eats well and is able to move. Deeper Stage 3 and Stage 4 ulcers may take six weeks to three months to heal.

For chronically ill people who have multiple risk factors, such as incontinence, an inability to move and circulatory problems, the fight against bedsores is often a long-term battle.

Sources: Harvard Medical School's Consumer Health Information; Centers for Medicare & Medicaid Services; National Institute of Arthritis and Musculoskeletal and Skin Diseases; www.bed-sores.info