About Pressure Ulcers

Also known as “Bedsores” or “Pressure Sores,” Pressure ulcers are a type of chronic wound that results from the breakdown of skin when applying pressure, friction, or moisture to soft tissue over a bony prominence. If there is pressure on the skin, it reduces the blood flow in the area. Without enough blood, the skin may die and eventually an ulcer could develop.

People with medical conditions that limit their ability to change body positions are at the highest risk for a pressure ulcer. For example, people who use a wheelchair or those who are confined to a bed are most likely to be at high risk for developing pressure sores. Pressure ulcers most commonly occur on the following parts of the body such as: ankles, back, back of head, buttocks, elbows, heels, hips, and shoulders.


Factors that may cause a pressure ulcer are:

  • Extended use of a wheelchair
  • Extended periods in a bed
  • Age
  • Inability to move certain parts of your body without help because of a spine or brain injury or disease such as multiple sclerosis
  • Diseases that affects blood flow, including diabetes or vascular disease
  • Alzheimer’s disease or another condition that affects your mental status
  • Fragile skin
  • Urinary incontinence or bowel incontinence
  • Poor diet or malnutrition

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Stages of Pressure Ulcers

The National Pressure Ulcer Advisory Panel (NPUAP) categorizes pressure ulcers according to their severity. The categorization ranges from Stage I (earliest stage) through Stage IV (worst stage).

  • Stage I:

    A pressure ulcer in this stage shows a reddened area on the skin. This may be considered a sign that a pressure ulcer is developing. The NPUAP explains that this category may be difficult to detect in individuals with dark skin tones and patients with a Stage I pressure ulcer may feel the area either painful, firm, soft or warmer, or cooler as compared to adjacent tissue.

  • Stage II:

    At this stage the pressure ulcer tends to show partial thickness loss of dermis and the skin forms an open sore or blisters along with redness and irritation around the area. NPUAP states that at this stage bruising may be an indication for deep tissue injury.

  • Stage III:

    The NPUAP describes this category as a “Full thickness and skin loss. Subcutaneously fat may be visible but bone, tendon or muscle are not exposed.” At this stage, the ulcer looks like a crater and at the bottom of the wound you may find yellowish dead tissue which can extend below layers of the healthy skin.

  • Stage IV:

    The NPUAP describes this category as a “Full thickness and tissue loss.” At this stage the ulcer shows a large scale of loss of tissue and may expose muscle, bone, or tendons.

  • Unstageable/Unclassified:

    A pressure ulcer is considered unstageable or unclassified when the depth of the wound is unclear and the surface is completely obscured by a yellowish, tan, gray, green, or brown coloration in the wound bed.

  • Deep tissue injury – depth unknown:

    A deep tissue injury may be difficult to detect in individuals with dark skin tones. Purple or maroon color of the skin, skin is not broken, a blood-filled blister, painful, firm, mushy, warmer or cooler as compared to adjacent tissue are some of the characteristics of a pressure ulcer at this stage.

If you believe that you have signs of a pressure ulcer, blister, or an open sore, contact your doctor immediately. If you notice signs of infection, call your doctor immediately. Some signs of infection may include:

  • A foul odor from the sore
  • Pus coming out of the sore
  • Redness and tenderness around the sore
  • Skin close to the sore is warm and swollen

If an infection is not treated correctly and as soon as possible, it may spread to other parts of the body and cause serious problems. Contact your doctor immediately for a plan of care.

1. The National Pressure Ulcer Advisory Panel (NPUAP)
2. MedlinePlus is The National Library of Medicine and created to assist consumers in locating health information.

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