Pressure injuries have been recognized as a disease entity for quite some time. They have been found in Egyptian mummies, some of which are more than 5,000 years old. Egyptians used honey for the treatment of such injuries and wounds and a wide variety of topical remedies like honey, mouldy bread, meat, animal and plant extracts, copper sulphate, zinc oxide and alum have been used in the past.
In 19th century, Jean-Martin Charcot studied decubitus ulcers and subscribed to the “neurotrophic theory” for the causation of ulcer rather than the “pressure” as we believe today. Charcot directly related the occurrence of ulcer to the damage to central nervous system. ‘Decubitus ominosus’ was the term given to ulcer covered with eschar as it caused high mortality. Charcot described the decubitus ulcer in detail with its complications like ‘gangrenous pulmonary metastasis (infiltration)’ and spinal cord invasion. However, Brown-Sequard opposed this theory and proved that if the pressure is avoided in guinea pigs with spinal cord injury, the ulcer does not develop and the existing ulcer heals on relieving the pressure. According to Ayurveda, bed-sore is termed as “SayyajVrava” – ‘Sayyaj’ meaning bed and ‘vrava’ is ulcer or wound. Due to pressure ‘mamsadhatu’ (circulation) is affected and results in pressure injuries.
During the nineteenth century, discovery of bacteria by Pasteur, antisepsis by Lister and X-ray by Roentgen changed the understanding of these ulcers in general. The twentieth century brought in antibiotics which changed the scenario further. The later part of twentieth century witnessed studies on nutrition, trace elements, biomechanics and newer methods of management of these injuries.
Pressure injuries are caused by sustained pressure being placed on a particular part of the body.
This pressure interrupts the blood supply to the affected area of skin. Blood contains oxygen and other nutrients that are needed to help keep tissue healthy. Without a constant blood supply, tissue is damaged and will eventually die.
The lack of blood supply also means that the skin no longer receives infection-fighting white blood cells. Once an injury has developed, it can become infected by bacteria.
People with normal mobility do not develop pressure injuries, as their body automatically makes hundreds of regular movements that prevent pressure building up on any part of their body. For example, you may think that you are lying still when asleep, but you may shift position up to 20 times a night.
Pressure injuries can be caused by:
Pressure from a hard surface – such as a bed or wheelchair
Pressure that is placed on the skin through involuntary muscle movements – such as muscle spasms
Moisture – which can break down the outer layer of the skin (epidermis)
The time it takes for a pressure injury to form will depend on:
The amount of pressure
How vulnerable a person’s skin is to damage
Grade three or four pressure injuries can develop quickly. For example, in susceptible people, a full-thickness pressure injury can sometimes develop in just one or two hours. However, in some cases, the damage will only become apparent a few days after the injury has occurred.
The parts of the body most at risk of developing pressure injuries are those that are not covered by a large amount of body fat and are in direct contact with a supporting surface, such as a bed or a wheelchair.
For example, if you are unable to get out of bed, you are at risk of developing pressure injuries on your:
Shoulders or shoulder blades
Back of your head
Rims of your ears
Knees, ankles, heels or toes
Tail bone (the small bone at the bottom of your spine)
If you are a wheelchair user, you are at risk of developing pressure injuries on:
The back of your arms and legs
The back of your hip bone
Severity of pressure injuries
Healthcare professionals use several grading systems to describe the severity of pressure injuries. The most common is the European Pressure Ulcer Advisory Panel (EPUAP) grading system. The higher the grade, the more severe the injury to the skin and underlying tissue.
Grade / Category / Stage 1
A grade one pressure injury is the most superficial type of ulcer. The affected area of skin appears discoloured – it is red in white people, and purple or blue in people with darker-coloured skin. Grade one pressure injuries do not turn white when pressure is placed on them. The skin remains intact, but it may hurt or itch. It may also feel either warm and spongy, or hard.
Grade / Category / Stage 2
In grade two pressure injuries, some of the outer surface of the skin (the epidermis) or the deeper layer of skin (the dermis) is damaged, leading to skin loss. The ulcer looks like an open wound or a blister.
Grade / Category / Stage 3
In grade three pressure injuries, skin loss occurs throughout the entire thickness of the skin. The underlying tissue is also damaged, although the underlying muscle and bone are not. The injury appears as a deep, cavity-like wound.
Grade / Category / Unstageable Pressure Ulcer
An Unstageable pressure injury is a minimal grade 3 and has the potential to be a grade 4 pressure injury. In this type of injury the wound bed is not visible due to the presence of slough or necrotic tissue. Grading this type of pressure injury may not be possible until the ulcer is debrided. An unstageable pressure injury can be seen as a localised area of purple discoloration over intact skin, or blood blister, due to damage of underlying soft tissue. It is possible that damage is recoverable with effective off-loading of pressure on the area.
Grade / Category / Stage 4
A grade four pressure injury is the most severe type of pressure injury. The skin is severely damaged and the surrounding tissue begins to die (tissue necrosis). The underlying muscles or bone may also be damaged.
People with grade four pressure injuries have a high risk of developing a life-threatening infection.
There are several factors that increase the risk of developing pressure injuries.
Possible reasons for having a mobility problem are:
Having a spinal cord injury that causes some or all of your limbs to be paralysed
Brain damage caused by an event such as a stroke or severe head injury, which results in paralysis
Having a condition that is causing progressive damage to the nerves your body uses to move parts of the body – such as Alzheimer’s disease, multiple sclerosis (MS) or Parkinson’s disease
Having severe pain that makes it difficult to move some or all of your body
Having a fractured or broken bone
Recovering from the effects of surgery
Being in a coma
Having a condition that makes it difficult to move your joints and bones – such as rheumatoid arthritis
Reasons that your diet may lack nutrition include:
Anorexia Nervosa – a mental health condition where a person has an unhealthy obsession with maintaining a low body weight
Dehydration – you do not have enough fluids in your body
Dysphagia – difficulty swallowing food
Health conditions that can make you more vulnerable to pressure injuries include:
Type 1 diabetes and type 2 diabetes – the high levels of blood sugar associated with diabetes can disrupt normal blood flow
Peripheral arterial disease (PAD) – blood supply in the legs becomes restricted due to a build-up of fatty substances in the arteries
Heart failure – previous damage to the heart means it is no longer able to pump enough blood around the body
Kidney failure – the kidney loses most or all of its functions, which can lead to a build-up of dangerous toxins (poisons) in the blood that can cause tissue damage
Chronic obstructive pulmonary disease (COPD) – a collection of lung diseases; the low levels of oxygen in the blood associated with COPD can make the skin more vulnerable to damage
There are several reasons why ageing skin is more vulnerable to pressure injuries. These include:
With age, the skin loses some of its elasticity (stretchiness), which makes it more vulnerable to damage
Reduced blood flow to the skin, due to the effects of ageing
The amount of fat under the skin tends to decrease as people get older
Both urinary incontinence (inability to control your bladder) and bowel incontinence (inability to control your bowels) can cause certain areas of the skin to become moist and vulnerable to infection. This can cause pressure injuries to form.
Mental health conditions
People with severe mental health conditions such as schizophrenia (a condition where people have problems telling the difference between reality and imagination) or severe depression have an increased risk of pressure injuries for a number of reasons. These include:
Their diet tends to be poor
They often have other physical health conditions, such as diabetes or incontinence
They may neglect their personal hygiene, making their skin more vulnerable to injury and infection
Are Pressure Injuries Avoidable?
Avoidable means that the person receiving care developed a pressure injury and the provider of care did not do one of the following:
Evaluate the person’s clinical condition & pressure injury risk factors.
Plan & implement interventions that are consistent with the persons needs and goals, and recognised standards of practice.
Monitor and evaluate the impact of interventions; or revise the interventions as appropriate.
Unavoidable means that the person receiving care developed a pressure injury even though the provider of care had evaluated the person’s clinical condition and pressure injury risk factors.
Planned and implemented interventions that are consistent with the persons needs and goals & recognised standards of practice.
Monitored and evaluated the impact of the interventions.
Revised the approaches as appropriate.
Or the person refused to adhere to prevention strategies in spite of education of the consequences of non-adherence.
Examples when unavoidable
Critical illness, with spinal instability that would inhibit repositioning.
Patient’s who refuse to be repositioned / use pressure reducing / relieving devices!!
Terminally ill who can’t tolerate frequency of positional changes.
Unknown to a health professional.
If the patient has mental capacity and refuses to be repositioned.
Carrying out Regular Skin Inspections
Assessment of most vulnerable areas.
Heels, sacrum, ischial tuberosity’s, femoral trochanters, skull, elbows, shoulders, back of head and toes.
Individuals should be encouraged, when able to do so, to inspect their own skin. following education.
Is the mattress / cushion / support surface suitable – If not, re-evaluate / re-place with a more appropriate one. Prevention is cheaper than the cure and more importantly kinder to the patient / user.