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Pressure Sores

(Bedsores; Decubitus Ulcers; Pressure Ulcers; Pressure Injuries)


The Manual's Editorial Staff

Reviewed/Revised Nov 2023
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What are pressure sores?

Pressure sores, often called bedsores, are skin injuries caused by steady pressure on one area of skin. The pressure cuts off blood flow to the area, which can damage the skin.

  • Pressure sores most often happen on bony parts of the body, like the tailbone, hips, heels, and elbows

  • Pressure sores are common in people who are bedridden or chairbound, who can’t move normally, or who have a cast or splint that presses too tightly

  • Changing positions helps prevent pressure sores

  • People who can’t move themselves should have their position changed every 1 to 2 hours

  • Most pressure sores can be prevented by changing position often and keeping the skin clean and dry

What causes pressure sores?

Pressure sores are caused by:

  • Steady pressure against an area of skin, particularly the skin over a bony area

  • Steady pressure for more than an hour or two, which cuts off blood flow to the skin

People who are awake and able to move constantly shift their position without thinking. If people don't shift position, after an hour or so, the weight of their body shuts off blood flow to the skin they're lying on. The longer the pressure continues, the worse the skin damage.

Common Sites for Pressure Sores

Common Sites for Pressure Sores

Who is at risk of pressure sores?

People at risk of pressure sores include those who:

Pressure sores can form very quickly, sometimes within a few hours.

What are the symptoms of pressure sores?

Pressure sores range from mild (stage 1) to severe (stage 4). Untreated sores get deeper and deeper.

  • At first, the skin turns red and hurts

  • Then the top layer of skin blisters or wears off

  • Eventually, the sore goes all the way through the skin, leaving a hole (ulcer)

  • The ulcer can be open or covered by a thick scab of dead skin

Ulcers can get infected. Infected ulcers have a red area around them and may drain pus.

How does the doctor know there's a pressure sore?

People who are confused or aren't able to feel pain won't notice a pressure sore developing. If you're taking care of someone at risk, you must watch that person closely for the first sign of a pressure sore.

Doctors recognize a pressure sore by how it looks.

When pressure sores don't heal, doctors may look for infection by:

How do doctors treat pressure sores?

Doctors will:

  • Clean the sores with sterile saline (salt water)

  • Remove dead tissue with scissors and a scalpel

  • Cover the sores with special bandages to protect them and help them heal

  • Sometimes, do surgery to close large pressure sores

To help sores heal and prevent more sores, doctors will also:

  • Make sure the person changes body position more often

  • Make a written schedule for caregivers for when to change the person's body position

  • Use tools like pads and pillows to make sure no single body part is getting too much pressure

  • Give suggestions for a healthier diet

How can pressure sores be prevented?

Doctors try to prevent pressure sores because they’re hard to treat.

For a person who is bedbound or chairbound, caregivers should:

  • Look at the skin each day

  • Adjust the person's position every 1 to 2 hours

  • Keep the skin dry and clean

  • Carefully check skin for redness or other changes in color at pressure areas

  • Change bed sheets as soon as they get wet

  • Cushion bony body parts with protective coverings or pillows

  • Sometimes use a special mattress or wheelchair cushion that gives pressure relief

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