Pressure ulcers often develop slowly but can develop in just a few hours with the right conditions.

Pressure ulcers are likely to develop faster when there is higher pressure on a smaller area, and more slowly when there is lower pressure over a wider area.

What are the Early Signs of Pressure Ulcer Development?

Early signs of pressure ulcer development include:

• A change in the colour of the skin. People with pale skin are more likely to see red patches on the skin, and people with darker skin area more likely to see purple or blue patches.
• Reddening of the skin that does NOT turn white when you press it. This is called a ‘non-blanching erythema’.
• Any unusual changes in skin texture may be related to pressure damage. Common changes include skin feeling spongy or ‘boggy’.
• A patch of skin that feels cooler or warmer to the touch than others.
• A sore or itchy patch of skin.

Bedsores fall into one of several stages based on their depth, severity and other characteristics. The degree of skin and tissue damage ranges from red, unbroken skin to a deep injury involving muscle and bone. Skin showing these signs of pressure ulcer development may be referred to as ‘category one’.

See our related article for more information on the staging of pressure ulcers.

What are the Later Signs of Pressure Ulcer Development?

As pressure ulcers worsen, they may break the skin. Signs of worsening pressure ulcers include:

• An open wound or
• A deep wound that reaches the deeper layers of the skin.
• A very deep wound that may reach the muscle and bone.

When should I get help for a Pressure Ulcer?

The NHS website says that if you’re in hospital or a care home, you should tell your healthcare team as soon as possible if you develop symptoms of a pressure ulcer as it will probably continue to get worse if nothing is done about it.

If you’re recovering from illness or surgery at home, or are caring for someone confined to bed or a wheelchair, contact your GP surgery if you think you or the person you’re caring for might have a pressure ulcer.

Get medical advice immediately if there is:

• Red, swollen skin
• Pus coming from the pressure ulcer or wound
• Cold skin and a fast heartbeat
• Severe or worsening pain
• A high temperature (fever) of 38C (100.4F) or above

These symptoms could be a sign of a serious infection that needs to be treated as soon as possible.

Pressure ulcers vary in size and severity of the tissue affected, ranging from reddening of the skin to damage to muscle and underlying bone.

How are Pressure Ulcers Staged / Graded / Classified?

According to the international classification system pressure ulcers can be staged as one of six categories.

Superficial

Stage 1: Intact skin with persistent reddening, known as ‘non-blanching erythema’. For more information on non-blanching erythema, click here.

Stage 2: An abrasion or a blister can be seen, without bruising. There is some skin loss or damage affecting the top skin layers.

Superficial ulcers are more difficult to spot than deep ulcers. For information on the warning signs of pressure ulcer development click here.

Deep

Stage 3: Full thickness skin loss which can expose fat in areas where this exists. Damage is limited to the skin and fat layers.

Stage 4: Full thickness skin loss with damage to the underlying structures, such as tendons or bone, which may be exposed.

Other

Deep tissue injury: Tissue injury hidden under intact skin. These appear as deep bruises and can quickly deteriorate into a high-stage pressure ulcer. For more information on why deep tissue injuries occur, click here.

Unstageable Pressure Injury: Pressure ulcer with an undetermined level of tissue injury because the entire base of the wound is covered by slough tissue.

Figure 1 Staging of pressure injury, NPUAP resources

The grading of a pressure ulcer is a critical part of the process of caring for a person with pressure ulcers.

While treatment is tailored to the individual, as may factors can impact the development of a pressure injury, the grade of pressure sore is an important part of creating a treatment/management plan.

For more information on what the risk factors are for developing a pressure injury, click here.

While the major factor in the development of pressure injury is pressure itself shear and friction forces also play a part.

What are shear and friction?

When you move over a surface and remain in contact with it, the skin gets pulled along that surface. You can feel this ‘drag’ effect if you run your hand over something.

This ‘drag’ is caused by friction and leads to a difference in the movement of the skin and the deeper tissues.

This difference is called shear and is an important factor in injury development.

How can shear and friction lead to a pressure ulcer?

Shear causes stretching and tearing of blood vessels which reduces blood flow, increases blood pooling and can lead to cell damage.

Shearing stops or reduces blood flow more easily than pressure alone (for example, it is easier to cut off flow in a water hose by bending than by pinching it).

Although shear and friction causes tissue damage slightly differently to pressure, the damage produced is the same as with pressure.

Importantly, it is difficult to create pressure without shear, and shear without pressure, so the two usually go hand-in-hand.

For information on how pressure leads to pressure injury, see our article How Pressure Causes Pressure Ulcers.

How can repeated friction cause a pressure ulcer?

As well as being a key element of making shear force, friction between the skin and the stationary surfaces such as bed clothes can result in the loss of the top layer of the skin (the stratum corneum).

Think about repeatedly rubbing your skin against a surface – after a time, the skin would start to become red and sore. This is due to friction.

This inflammation can lead to deeper injury or could be the initial damage needed to start pressure ulcer formation.

When there is loss of the top skin layer, there is also a breach in the barrier against infection.

How can friction and shear be reduced?

There are several strategies to reduce shear and friction forces:

• Use low-friction clothing such as Parafricta undergarments and socks to reduce friction on the vulnerable heel and pelvic areas. These can be especially useful for people who push themselves back up the bed using their heels, or who have involuntary leg movement.
• Use positioning aids to maintain comfortable positioning, without using friction to maintain body position.
• Use a profiling bed to maintain position with a knee break – this stops people sliding down the bed and needing to move themselves across the bed surface.

Who is at Risk of Developing Pressure Ulcers?

The risk of you developing a pressure ulcer is affected by a whole host of health and environment associated factors.

In fact, more than 100 risk factors for pressure ulcers have been identified in the literature.

This means that anyone can get a pressure ulcer, although the following things can make them more likely to form:

• Being elderly – older people are more likely to have mobility problems and have skin that is more easily damaged.
• Being confined to bed or a chair with illness or after surgery.
• Full or partial paralysis, reducing movement.
• Incontinence leading to damp, irritated skin.
• Reduced nutrition, either through a poor quality diet or low calorie intake.
• Medical conditions that affect blood supply, make skin more fragile or cause movement problems – such as diabetes, peripheral arterial disease, kidney failure, heart failure, multiple sclerosis (MS) and Parkinson’s disease.
• History of previous pressure injury.

Pressure ulcers can develop rapidly given the right conditions.

There are over 100 risk factors for developing pressure ulcers, so not all of them can be controlled. However, the key risk factors should be taken into account as part of a pressure ulcer prevention strategy.

Read more about the risk factors for pressure ulcer development.

Creating a Plan

A healthcare professional must do a routine assessment on anyone at high risk of pressure ulcer development.
This assessment will form the basis of a care plan that reduces the risk of pressure ulcer development. These plans may include positional changes, supportive nutrition, a skin care routine and pressure-reliving equipment.
Anyone confined to a bed or chair for a prolonged period should have their risk of pressure ulcer development assessed.

Positional Changes

Regular movement helps redistribute pressure. In fact, people at full health naturally change position regularly without even thinking about it due to feedback from the skin.

People who cannot do this repositioning themselves need assistance to do so.

This repositioning should be throughout the day and night, and the frequency should be set by a healthcare professional.
Some positioning aids can be helpful for managing repositioning and supporting people in necessary positions.

Skin Care

Healthy skin can withstand pressure and friction/shear forces more easily than damaged skin.

Skin health can be supported with barrier creams, a good diet and maintained personal hygiene.

It is also important to regularly check the skin for signs of discolouration that could be an early sign of pressure injury.

For more information on the early signs of pressure injury, click here.

Pressure-Relieving Equipment

Pressure-reliving equipment works to redistribute pressure away from vulnerable parts of the body.

Vulnerable areas are usually the most bony areas, or areas which are under higher pressure due to seating or lying position.

These can be:

1. Active – Mattresses/cushions are filled with air cells which inflate and deflate to move pressure onto different parts of the body in turn.
2. Static – Viscoelastic (memory-foam style) mattresses/cushions which mould to the shape of the body to spread out pressure much more evenly.

See our full range of pressure reliving equipment here.