A pressure sore is a lesion that develops on the skin and underlying tissues due to unrelieved pressure usually over a bony prominence. The skin and tissues rely on an adequate blood supply for oxygen and nutrients. When tissues are compressed for an extended period from hours to days, blood supply can be cut off, leading to development of a sore.
Pressure sores result from lying or sitting in one position for too long a time. Prolonged pressure cuts off the blood supply to tissues that are compressed between a bony area and a mattress, chair, or other object. Without oxygen and nutrients, the tissue starts to die.
Several factors contribute to the development of pressure sores including:
Pressure—Pressure sores can result from the inability to change position or to feel discomfort caused by pressure. People with normal mobility and sensation change position automatically, without thinking.
Friction—Even friction from pulling someone across bed sheets can damage small blood vessels that supply the skin tissue.
Moisture—This can come from sweating due to an elevated temperature (fever) or leakage of urine or stool.
—Extra weight increases pressure on the skin over the bones and joints.
Reddish or purplish skin discoloration, often over a bony area
Pain or itching of the skin
Blistering, sores, skin breakdown, or drainage
If the redness remains a half hour after the pressure has been removed, the skin will likely break down. The reddened area may blister and a shallow ulcer may develop. Fluid may drain. The wound can deepen and can extend through fat and muscle to the bone. The area may be painful. The wound can become infected, with redness, swelling, odor, pus, warmth, and fever. If untreated, the infection can progress to
gangrene, a blood infection, or an infection of the bone beneath.
The doctor will ask about your symptoms and medical history, and perform a physical exam. The doctor will examine the ulcer and note the location, shape, size, depth, stage, and any formation of pockets or cavities. Pressure sores are staged according to the depth and tissues that are involved.
Tests may include:
Wound culture—taking a sample of material from a sore to be tested for bacteria
Blood tests—to check for infection and nutritional status
Most pressure ulcers can be prevented. Suggestions include:
Follow these tips when repositioning:
Change position in bed at least every two hours or, in a wheelchair, at least hourly. If able to move yourself, shift position every 15 minutes.
Maintain good body alignment.
To prevent sliding, do not elevate the head of the bed greater than 30°. Discuss the bed elevation with your doctor in case this is contraindicated because of risk of difficulty breathing, choking, or aspiration.
Find a sitting or lying position that is 30° toward one side or the other, but not squarely on the hip.
Place a pillow under calves to keep the heels off the mattress.
Place a pillow between the knees.
Do not use donut-ring cushions, which can cut off circulation.
Talk to the doctor about using:
A special foam mattress designed to reduce the risk of pressure sores
A mechanical mattress or overlay (goes over the mattress) that inflates and deflates to change the pressure on the body
Use a special cushion on the wheelchair.
Wear special pads to protect skin that is resting against braces and other devices.
When moving someone, lift rather than drag.
Use assistive devices, such as transfer boards and mechanical lifts.
Try placing a sheepskin under a body part to decrease friction.
Keep the skin clean and dry.
Do not massage bony areas.
If incontinent, use a protective cream on skin that may come in contact with urine or stool. Frequently check the patient, and do not let feces or urine remain for extended periods of time.
Check the skin at least daily for signs of pressure problems.
Keep sheets clean and free of wrinkles.
Maintain good nutrition.
Use dressings on areas that are prone to pressure ulcers
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11/25/2013 DynaMed's Systematic Literature Surveillance. ...(Click grey area to select URL) Moore ZE, Webster J. Dressings and topical agents for preventing pressure ulcers. Cochrane Database Syst Rev. 2013 Aug 18;8.