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Pressure Sores


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Pressure sores, also called bed sores, occur when the skin breaks down from constant pressure, especially from sitting or lying in one position for any extended period of time. The pressure cuts off the blood supply to the underlying skin, fat, and muscle. These sores usually occur over bony prominences — tailbone, buttock, heel, shoulder blade, elbow, and occasionally the back of the head. However, pressure sores are not limited to these areas, and can occur other places as well. Sores may also develop from friction to the skin. This is called shear, and may result from sliding across a bed or wheelchair seat. Because the skin is much more likely to break down if it is moist or infected, incontinence of bowel or bladder can add to the problem.

Risk factors

Several interacting risk factors have been identified in the development of pressure sores:

  • Immobility or inactivity
  • Decreased sensation
  • Bowel or bladder incontinence
  • Poor nutrition
  • Older age
  • Obesity — the extra weight can contribute to the formation of sores
  • Underweight — the bony prominences can contribute to the formation of sores
  • Dry skin and or dehydration
  • Moist skin
  • Smoking
  • Diabetes, anemia, or cardiovascular disorders
  • Cognitive confusion

Stages of progression

Pressure sores begin as relatively benign problem, but can quickly progress to a more serious problem if left untreated.

  • Stage 1 — A small area of warm, reddened or purpled skin that does not return to its natural color when pressed.
  • Stage 2 — The outer layer of skin breaks down. Blistering and swelling as well as warmth and redness may be seen.
  • Stage 3 — Live tissue dies. The sore extends down into the deep skin layers and to the fat and muscle immediately beneath the skin. This hole or crater has a foul smell.
  • Stage 4 — The sore extends down to the deep muscle, possibly down to the bone. Infection may occur and may tunnel under the skin, increasing the size of the sore.

Prevention and treatment

The best way to treat a pressure sore is to avoid developing one in the first place.

Pressure sores can be prevented in the following ways:

  • If you can, keep mobile.
  • Unless advised differently by your physician, drink a lot of fluids and eat a well-rounded diet.
  • If you are not mobile, your position must be changed at least every two hours.
  • Your bed should be fitted with a mattress or a mattress pad that is capable of alternating and distributing the pressure applied by the body on the mattress. Foam “egg-crate” mattresses are not recommended for prevention.
  • You should use padding or boots for pressure points (e.g., elbows, heels). Nurses, physical therapists, and/or physiatrists (physicians specializing in rehabilitation medicine) are the best sources of guidance about prevention of pressure sores.
  • If you use a wheelchair, it is important that you sit on a cushion that distributes your weight. A gel-filed cushion is often recommended. Ask your physician or physical therapist about an evaluation by a seating specialist. Sitting on pillows, towels, or foam pads may add to your risk of developing pressure sores.

The treatment of pressure sores becomes more difficult as the sore advances in severity. A Stage 1 sore is usually well managed by eliminating the source of the pressure. This should result in a rapid resolution of the early pressure sore. Stage 2 sores can be treated by medication and protective coverings, under the advice of a physician or wound specialist who may be a nurse of physician. The treatment for a Stage 3 or 4 sore often involves long-term dressings, a special bed, medications, (including antibiotics if there is insufficient healing), and perhaps even surgical intervention.

It is thus imperative to see your physician if you suspect that a pressure sore has begun.

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