10.4 Pressure Injuries
Open Resources for Nursing (Open RN)
The remainder of this chapter will focus on applying the nursing process to a specific type of wound called a pressure injury. Pressure injuries are defined as, “Localized damage to the skin or underlying soft tissue, usually over a bony prominence, as a result of intense and prolonged pressure in combination with shear.” (Note that the 2016 NPUAP Pressure Injury Staging System now uses the term “pressure injury” instead of the historic term “pressure ulcer” because a pressure injury can occur without an ulcer present.) Pressure injuries commonly occur on the sacrum, heels, ischia, and coccyx and form when the skin layer of tissue gets caught between an external hard surface, such as a bed or chair, and the internal hard surface of a bone.
Shear occurs when tissue layers move over the top of each other, causing blood vessels to stretch and break as they pass through the subcutaneous tissue. For example, when a client slides down in bed, the outer layer of skin remains immobile because it remains attached to the sheets due to friction. However, the deeper layer of tissue (attached to bone) moves as the client slides down. This opposing movement of the outer layer of skin and the underlying tissues causes the capillaries to stretch and tear, which then causes decreased blood flow and oxygenation of the surrounding tissues resulting in a pressure injury.[1]
Friction refers to rubbing the skin against a hard object, such as the bed or the arm of a wheelchair. This rubbing causes heat, which can remove the top layer of skin and often results in skin damage. See Figure 10.13[2] for an illustration of shear and friction forces in the development of pressure injuries.
Hospital-acquired or worsening pressure injuries during hospitalization are considered “never events,” meaning they are a serious, preventable medical errors that should never occur and require reporting to The Joint Commission. Additionally, the Centers for Medicare and Medicaid Services (CMS) and many private insurers will no longer pay for additional costs associated with “never events.”[3],[4] Pressure injuries can be prevented with diligent assessment and nursing interventions such as frequent repositioning and providing good skin care.
Staging
When assessed, pressure injuries are staged from 1 through 4 based on the extent of tissue damage. For example, Stage 1 pressure injuries have the least amount of tissue damage as evidenced by reddened, intact skin, whereas Stage 4 pressure injuries have the greatest amount of damage with deep, open ulcers affecting underlying tissue, muscle, ligaments, or tendons. See Figure 10.14[5] for images of four stages of pressure injuries.[6] Each stage is further described in the following subsections.
Stage 1 Pressure Injuries
Stage 1 pressure injuries are intact skin with a localized area of nonblanchable erythema where prolonged pressure has occurred. Nonblanchable erythema is a medical ter