The purpose of the clinical practice guideline is to promote an evidence based approach in the identification and classification of pressure related injury, to the skin and underlying tissue.

• Accurate assessment of wound aetiology in the identification of a pressure injury.

• Consistent use of a standardised pressure injury classification system when assessing a pressure injury.

Bony prominence: An anatomical projection of bone.

Clinician: A health care professional who is directly involved in a person's care.

Erythema: Superficial redness of the skin or mucous membranes, caused by increased blood flow in the superficial capillaries; note that erythema does not occur as red across all skin tones.

Eschar: Necrotic, devitalised tissue that appears black or brown, can be loose or firmly adherent, hard or soft and may appear leathery.

Friction: A mechanical force that occurs when two surfaces move across one another, creating resistance between the skin and contact surface.

Incontinence Associated Dermatitis (IAD): Describes skin damage associated with exposure to urine or faeces.

Person: Refers to a consumer, patient, client or resident.

Pressure Injury: 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 and/or friction.

Pressure injury classification system: Pressure injuries are to be classified as per the international National Pressure Injury Advisory Panel (NPUAP) / European Pressure Ulcer Advisory Panel (EPUAP) Pressure Ulcer Classification System.

Shear: A mechanical force created from a parallel load, which causes the body to slide against resistance between the skin and a contact surface. During this process the outer layers of the skin (the epidermis and dermis) remain stationary, whilst the deep fascia moves with the skeleton, thereby creating a distortion in the blood vessels and lymphatic system between the dermis and deep fascia. This leads to thrombosis and capillary occlusion.

Slough: Non-viable tissue of varying colour that may be loose or firmly attached, slimy, stringy or fibrinous.

T.I.M.E. clinical decision support tool: An internationally validated support tool used as a means of standardising the assessment and management of wounds (Acronym: Tissue management, Infection and inflammation control, Moisture balance, Epithelial edge advancement).

Persons affected: All persons admitted to Grampians Health Ballarat (GHB); including across all departments, units, wards, acute, subacute, mental health and residential facilities.

Responsible persons: All clinicians involved in a person's care.

Aetiology of pressure injury

A pressure injury is localised damage to the skin and/or underlying tissue, caused by pressure or pressure in combination with shear and/or friction. Pressure injuries usually occur over a bony prominence, however they may also be due to unrelieved pressure from a medical device or other objects. Tissue damage occurs when the soft tissue is compressed and/or distorted between the person's bodyweight and an external surface, leading to tissue ischaemia.

It is important to determine the aetiology of the tissue damage to differentiate between Incontinence Associated Dermatitis (IAD) and pressure injury. Although the two share common risk factors, the skin damage from IAD is initiated on the surface of the skin, whilst pressure injury damage is initiated by changes of the soft tissue below and within the skin. Refer to Appendix 1 for a pictorial guide of the differences between IAD and pressure injury.

Factors that influence susceptibility to pressure injuries

• Intensity and duration of pressure

• Tissue tolerance to pressure: including skin temperature, tissue deformation and chronic illness

• Exposure to shear, friction and pressure

Risk factors

• Activity and mobility limitations

• Skin integrity damage

• Peripheral perfusion, circulation and body temperature

• Nutrition: malnutrition and obesity

• Moisture: exposure to urinary and faecal incontinence, perspiration and wound exudate

• Acutely unwell; chronic illness

• Comorbidities and mental health status

• Sensory perception limitations

• Lifecycle phases: neonates, children and the elderly
  

Common anatomical sites for pressure injury

EQUIPMENT

• GHB Pressure Injury Prevention and Management Plan MR/202.5 for the acute, subacute and mental health settings.

• GHB Wound Chart MR/202.0 for the acute, subacute and mental health settings and the iCARE Wound Chart for residential settings.

NOTE: Wound charts are to be commenced for all stages of pressure injury and the assessments are to reflect the principles of the T.I.M.E. clinical decision support tool. Refer to Appendix 2.

Pressure Injury Classification System

The Australian Commission on Safety and Quality in Health Care (ACSQHC) and the National Safety and Quality Health Service (NSQHS) Standard, Comprehensive Care Standard, have stipulated that health service organisations stage pressure injuries as per the international NPUAP/EPUAP Pressure Ulcer Classification System. Refer to Appendix 3.

When classifying a pressure injury, it is important to note that:

• Pressure injury classification is based upon visualising and palpating the tissues, including the skin and underlying tissues and structures.

• Necrotic tissue (slough, eschar) appears in full-thickness pressure injuries.

• The depth and severity of a pressure injury varies upon the anatomical location. Depending upon the location of the wound, underlying structures may be close to the skin surface, ie: a toe in comparison to the buttock.

• It is not always possible to identify the early stages of pressure injury on persons with dark skin tones, as erythema cannot always be observed. Therefore, the early indicators of pain, localised heat, oedema and a change in tissue consistency (boggy, hard) are to be looked for. Comparing the skin colour of the affected area against the person's skin of an unaffected area, will also assist with identification. Refer to Appendix 4 for the Skin Tone Tool, a validated classification tool which shows a range of baseline skin tones.

Pressure injury stages and definitions

Stage 1

• Intact skin with non-blanchable erythema to a localised area, usually over a bony prominence. Darkly pigmented skin may not have visible blanching, however its colour may differ from the surrounding skin. The area may be painful, firm, soft, warmer or cooler as compared to adjacent tissue.

Stage 2

• Partial thickness loss of the dermis presenting as a shallow open ulcer with a red/pink wound bed, without slough. May also present as an intact or open/ruptured serum filled blister.

Stage 3

• Full thickness tissue loss. Subcutaneous fat may be visible but bone, tendon or muscle are not exposed. Slough may be present but it does not obscure the depth of tissue loss. Undermining and tunnelling may be present.

Stage 4

• Full thickness tissue loss with exposed bone, tendon or muscle. Slough or eschar may be present on some parts of the wound bed. Often includes undermining and tunnelling. The depth of a stage 4 pressure injury varies by anatomical location.

Unstageable

• Full thickness tissue loss in which the base of the ulcer is covered by slough (yellow, tan, grey, green or brown) and/or eschar (tan, brown or black) in the wound bed. Until enough slough and/or eschar is removed to expose the base of the wound, the true depth and stage cannot be determined.

Suspected Deep Tissue Injury

• Purple or maroon localised area of discoloured intact skin or a blood-filled blister, due to damage of the underlying soft tissue from pressure and/or shear. The area may be preceded by tissue that is painful, firm, mushy, boggy, warmer or cooler as compared with the adjacent tissue. Deep tissue injury may be difficult to detect in individuals with dark skin tones. Evolution may include a thin blister over a dark wound bed, which may further evolve and become covered by thin eschar.

Additional pressure injury definitions

Mucosal Membrane Pressure Injury

• Mucosal membrane pressure injuries are pressure injuries of the moist membranes that line the respiratory, gastrointestinal and genitourinary tracts. They are primarily caused by medical devices applying shear or a consistent pressure to the mucosa.

Device Related Pressure Injury

• Device related pressure injuries result from medical devices, equipment, furniture and everyday objects that have applied pressure to the skin. The resultant pressure injury generally conforms to the pattern or shape of the device. The term 'device related' describes the aetiology of the pressure injury rather than the severity or extent of tissue loss. Device related pressure injuries are to be staged as per the NPUAP/EPUAP Pressure Ulcer Classification System.

Reassessment

Pressure injuries can change rapidly, with improvement or deterioration indicated by a change in dimensions, tissue quality, wound exudate levels and signs of infection. Signs of deterioration should be addressed immediately and the pressure injury management plan adjusted accordingly.

• Pressure injuries are to be re-assessed at least weekly to monitor progress towards healing, with the physical characteristics of the wound bed, surrounding skin and soft tissue assessed during each pressure injury review.

• Ongoing observation should be conducted daily and/or with each dressing change.

• Pressure injuries are only restaged if the injury has deteriorated.

• Healing pressure injuries are not back or reverse staged, as they do not heal in reverse. For example, the defect of a healing stage 4 injury grows shallower as the necrotic tissue is replaced with granulation (scar) tissue and then covered with epithelial tissue; the injury does not develop new layers of muscle, subcutaneous tissue and dermis.

• When documenting, a healing pressure injury is referred to as a healing stage__ pressure injury and at full re-epithelialisation it is referred to as a healed stage__ pressure injury.

• A healed pressure injury will only ever reach 70% of the full tensile strength pre-injury and only after 1-2 years of the maturation phase; this area therefore remains at an increased risk of sustaining further injury.

• The exception to the no back or reverse staging rule, is when an unstageable pressure injury has been debrided to reveal the full extent of the tissue damage; at this time an unstageable pressure injury may be restaged as a stage 3 or 4 pressure injury.