Pressure Injuries

Pressure injuries are also known as pressure ulcers, bed sores or decubitus ulcers.

A pressure injury is a localised injury to the skin and/or underlying tissue, usually over a bony prominence, as a result of pressure, or pressure in combination with shear.

Prolonged pressure cuts off the blood supply to the skin, causing damage to the skin, and sometimes other tissue and muscle. The damage may occur in a very short time but it might not be noticed until days later when the skin begins to break down.

People of all ages, including babies and children can be at risk of developing pressure injuries. They can occur in people who lie in bed or sit in chairs for long periods without moving; people who aren’t eating well, have problems with skin wetness (such as with loss of bowel or bladder control), have a medical condition that restricts their ability to move or don’t feel pain from pressure.  

There are 4+2 stages of pressure injuries.

The first stage is the mildest, marked by a redness that does not become white when you press your finger on it, or pain, burning, or itching in a specific area.

The second stage is if the injury below the surface of the skin forms an open wound or blister.

In stage three, the wound reaches the fat tissue under the skin. Signs of infection may occur at this stage.

Stage four is the most severe. The wound may affect muscles and ligaments and express with symptoms such as black skin, deepening of the wound, and signs of infection.

When the wound is covered with slough or dead (black) tissue so we can't see the fulll depth of the wound, this is called an unstageable pressure injury.

If the skin is still intact, but a large blood filled blister of purple discolouring suggests the presence of damage to the underlying tissue layers, this is labelled a suspected deep tissue injury.

Pressure injuries can cause pain, loss of function, infection, delayed healing, altered body image, anger, depression, increased mortality and morbidity, longer hospital stays and ACC treatment injury claims and care costs.

It can also create a toll on the person affected, carers and their families/whānau.

Pressure injury prevention

Evidence shows 95% of pressure injuries are preventable through early identification of people at risk and subsequent careful preventative measures. 

There are key actions that are globally recognised and promoted to reduce the risk and impact of pressure injuries. For example, the SSKINS bundle provides a useful approach to ensure that no prevention element is missed. It includes considering or undertaking the following:

Skin care - keep the skin healthy moisturising dry skin and avoiding soaps

Skin Inspection – undertake regular skin checks for discolouration and pain, especially over bony prominences (such as hips and heels) and under or around medical devices

Keep moving – change position often

Incontinence– keep skin dry and clean

Nutrition – eat healthily and drink plenty of fluids.

Surface – provide a supportive and pressure relieving surface


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