Learning Objectives
By the end of this section, you will be able to:
- Define pressure injury
- Identify the causes of pressure injuries
- Identify the different stages of pressure injuries
- Discuss strategies for preventing and treating pressure injuries
Each year an estimated one to three million people in the United States are affected by skin and soft-tissue pressure injuries (Mondragon & Zito, 2024). According to the Agency for Healthcare Research and Quality, pressure injuries are considered “never events,” meaning they are preventable and thus should never happen; nevertheless, they can result in devastating consequences, including death, to a patient (Smith et al., 2018). Pressure injuries have a long history of nomenclature, including terms such as decubitus ulcer, pressure ulcer, and bed sore. Preventing pressure injuries is an interdisciplinary team effort that requires diligence, creativity, and education. The cornerstone of pressure injury prevention is to reduce pressure, moisture, and friction to any at-risk sites. As the bedside providers, nurses are key to preventing injuries.
Pathophysiology
Per the National Pressure Injury advisory panel, a pressure injury is localized damage to the skin and underlying soft tissue, typically over a bony prominence (Figure 28.4). The injury can present as intact skin or an open ulcer and may be painful.
Simplistically, a pressure injury occurs because of intense or prolonged pressure, or pressure in combination with shear, over a bony prominence. Thus, the causes may be multifactorial, involving both external and internal factors, but they all produce a common pathway that leads to ischemia and necrosis.
The tolerance of soft tissue for pressure and shear may also be affected by microclimate (e.g., skin temperature, moisture), nutrition, perfusion, comorbidities, and condition of the soft tissue. For example, moisture can cause ulcers and worsen existing ulcers via tissue breakdown and maceration.
Link to Learning
Visit the National Pressure Injury Advisory Panel site to access the most current and comprehensive guidelines for the prevention and treatment of pressure injuries.
Staging
The correct staging of a pressure injury has both clinical and legal implications. It is imperative to understand the pressure injury staging system when documenting the injury. Best practice tip: if the nurse is uncomfortable or unsure how to stage a pressure injury, it is best simply to describe the wound as it is assessed. Pressure injuries are the only wounds that are staged, and health-care workers must use the internationally accepted guidelines set forth by the National Pressure Injury Advisory Panel (NPIAP), the European Pressure Ulcer Advisory Panel (EPUAP), and the Pan Pacific Pressure Injury Alliance (PPPIA).
Stage 1
A Stage 1 pressure injury is considered intact skin with a localized area of nonblanchable erythema, or redness that does not fade when pressure is applied (Figure 28.5). In darkly pigmented skin, a Stage 1 pressure injury may appear as either a darker-pigmented or lighter-pigmented area over a bony prominence. Noticeable changes in sensation, temperature, or firmness may precede visual changes. Stage 1 changes do not include purple or maroon discoloration, as such findings may indicate deep tissue pressure injury.
Stage 2
A Stage 2 pressure injury is a partial-thickness loss of skin with exposed dermis (Figure 28.6). The wound bed is viable, moist, and pink or red; it may also present as an intact or ruptured, serum-filled blister. Adipose and deeper tissues are not visible. Granulation tissue, slough, and eschar (hard black dead tissue) are not present. This stage should not be used to describe moisture-associated skin damage (MASD), including incontinence-associated dermatitis (IAD), intertriginous dermatitis (ITD), medical adhesive-related skin injury (MARSI), or traumatic wounds (skin tears, burns, abrasions).
Stage 3
A Stage 3 pressure injury is a full-thickness loss of skin; adipose tissue is visible in the ulcer, and granulation tissue and epibole are often present (Figure 28.7). Slough or eschar may also be visible. The depth of tissue damage varies by anatomical location; areas of significant adiposity can develop deep wounds. Undermining and tunneling may occur. Fascia, muscle, tendon, ligament, cartilage, and bone are not exposed. If slough or eschar obscures the extent of tissue loss, then such an injury is considered an unstageable pressure injury.
Stage 4
A Stage 4 pressure injury involves full-thickness skin and tissue loss with exposed or directly palpable fascia, muscle, tendon, ligament, cartilage, or bone in the ulcer (Figure 28.8). Slough or eschar may be visible. Epibole, undermining, or tunneling commonly occur. Depth varies by anatomical location.
Unstageable
An unstageable pressure injury is understood to have full-thickness skin and tissue loss, but the extent of tissue damage within the ulcer cannot be determined because it is obscured by necrotic tissue (Figure 28.9). If slough or eschar is removed, a Stage 3 or Stage 4 pressure injury will be revealed. Stable eschar on the heel or ischemic limb should not be softened or removed.
Deep Tissue Injury
A deep tissue pressure injury (DTPI) is characterized by persistent, nonblanchable discoloration that is deep red, maroon, or purple (Figure 28.10). It may involve intact or nonintact skin with possible epidermal separation that reveals a dark wound bed or blood-filled blister. Discoloration may appear differently in darkly pigmented skin. This injury results from intense or prolonged pressure and shear forces at the bone-muscle interface. The wound may evolve to reveal the actual extent of tissue injury or resolve without tissue loss. If necrotic tissue, subcutaneous tissue, granulation tissue, fascia, muscle, or other underlying structures are visible, this indicates a full-thickness pressure injury that should be staged as Stage 3, Stage 4, or unstageable. Do not use DTPI to describe vascular, traumatic, neuropathic, or dermatologic conditions.
Mucosal Membrane Pressure Injury
A mucosal membrane pressure injury occurs on mucous membranes with a history of a medical device used at the location of the injury. Due to the anatomy of the tissue, these ulcers cannot be staged. Examples of medical devices posing risk to mucosal membrane pressure injury development include nasogastric (NG) or orogastric (OG) tubes, oxygen cannulas or masks, endotracheal tubes, and urinary and fecal containment devices.
Medical Device-Related Pressure Injury
Medical device-related pressure injuries result from prolonged use of any device designed and applied for diagnostic or therapeutic purposes. The resultant pressure injury generally conforms to the pattern or shape of the device. The injury should be staged using the staging system. Examples of equipment and devices that may cause pressure injuries include but are not limited to:
- intravenous (IV) catheters, including hubs
- orthopedic devices
- SPO2 probes
- wires or lines, such as from ECG, blood pressure cuff, or IV lines
- bed pans
- feeding tubes
- restraints
- ID bands
- braces and casts
Prevention
The best way to prevent pressure injuries is to alleviate pressure; it is also important to decrease the incidence of contributing factors such as friction, shear, and moisture. Often, this can be easier said than done. Typically, the unofficial rule of turning and repositioning every two hours is implemented for all patients at risk for skin breakdown; although this is a general rule, some patients require more frequent turns (or fewer manual turns if they are able to reposition themselves). Specialty beds, pillow usage, and foam dressing applications can help reduce pressure load on bony prominences, which in turn reduces the risk of pressure injuries. Protocols and interdisciplinary teamwork can help reduce and prevent pressure injuries from forming.
Some institutions have implemented a turn team to help implement a “quality turn”; this procedure ensures that the patient is off-loaded from at-risk bony prominences and not propped sideways.
Screening Tools
Common screening tools to help identify patients at risk for pressure injury development are the Braden Scale and the Norton scale.
- The Braden Scale assesses six risk factors—sensory perception, moisture, activity, mobility, nutrition, and friction and shear—on a scale from 1 (poor) to 4 (excellent). A total score of 12 or less represents high risk.
- The Norton Scale assesses five risk factors—physical condition, mental condition, activity, mobility, and incontinence—on a scale from 1 (poor) to 4 (excellent). A total score of 14 or less represents high risk, with a score of 10 or less indicating very high risk.
Although these tools are helpful, recent studies have demonstrated that a nurse’s clinical judgment is just as, if not more, effective at identifying individuals at risk for pressure injury development.
Risk Factors
Common risk factors for development of a pressure injury include advanced age, immobility, friction, shear, poor nutrition, excessive moisture and incontinence, altered level of consciousness, poor perfusion, certain skin infections, and comorbid conditions.
Patients at the highest risk are patients in an operating room and those in critical care settings due to hemodynamic instability and the increased use of medical and life-sustaining devices and vasoactive drugs. Other at-risk populations include older adults and immunocompromised individuals.
Link to Learning
Several tools are available to help prevent pressure ulcers in hospitals and assess risk for skin breakdown and pressure injury development.
Treatment
Treatment of pressure injuries is similar to measures used for prevention. Keeping the patient off the wound is important to facilitate healing and remove the trigger. Treatment selection follows the same methodology described in the earlier discussion of prevention techniques: follow the principles of wound bed preparation and select the appropriate topical treatment. Nurses should conduct daily inspections of the wound for any signs of infection or decreased healing, collect data such as wound measurements (e.g., length, width, and depth), and administer any specialized wound treatment. When measuring length, use the patient’s head as top and feet as bottom for a directional pathway. Measure width from the patient’s right arm to left arm, and measure depth from the deepest part of the wound bed.