A Pressure Injury Primer: Fundamentals, Stages, and Prevention

Pressure injuries (PIs) are among the biggest challenges facing wound care providers

Formerly known as pressure ulcers, decubitus ulcers, or pressure sores, pressure injuries (PIs) are notoriously difficult to prevent and manage. They also are very costly — individual patient care for severe PIs ranges from $21,000 to more than $151,000. Pressure Injuries also cause pain, extensive and expensive treatment, and, in some patients, premature death. According to the AHRQ, it’s estimated that 2.5 million people will suffer a PI this year.

For Hospital Acquired Pressure Injuries (HAPIs), the situation is more severe:  The U.S. spends approximately $26.8 billion on caring for patients with HAPIs. The average HAPI costs hospitals up to $70,000 per case and are the second most common hospital lawsuit claim after wrongful death. More than 17,000 lawsuits arise due to PIs annually at an average settlement of $250,000.

The bottom line is that Pressure Injuries — especially HAPIs — are complex, difficult to treat, and at risk for re-occurrence. It’s critical on all members of your team understand the basics of PIs, from stages to treatment to cost.

What is a Pressure Injury?

Let’s start with the fundamentals.  A pressure injury is caused when skin integrity is broken down by some type of unrelieved pressure, leading to the destruction of normal structure and function. The National Pressure Injury Advisory Panel (NPIAP), the preeminent U.S. professional organization dedicated to prevention and management of PIs, uses these four criteria to define a PI: 

• A pressure injury is localized damage to the skin and underlying soft tissue, usually over a bony prominence.
• The injury can present as intact skin or an open ulcer, and may be painful.
• The injury occurs as a result of intense pressure, prolonged pressure, or pressure in combination with shear.
• The tolerance of soft tissue for pressure and shear may also be affected by microclimate, nutrition, perfusion, comorbidities and condition of the soft tissue.

Common places for PIs to develop include the back of the head, shoulders, elbows, buttocks, hips, ankles, and heels.

The 4 Stages of Pressure Injuries

NPIAP also provides descriptions of the stages of pressure injuries, which can be used by home health practitioners to determine the degree of injury and direct treatment. Here are the four stages of PIs as outlined by the NPIAP.

Stage 1

Non-blanchable erythema of intact skin. Intact skin with a localized area of non-blanchable erythema, which may appear differently in darkly pigmented skin. Presence of blanchable erythema or changes in sensation, temperature or firmness may precede visual changes. Color changes do not include purple or maroon discoloration; these may indicate deep tissue pressure injury.

• Stage 1 in Darkly Pigmented Skin: Research indicates that people with darker skin tones are more likely to develop higher stage pressure injuries, possibly because skin assessment protocols are less effective in identifying damage earlier. Pigmentation of the skin may prevent visualizing the reactive hyperemia in the pressure injury, says former NPIAP President Joyce Black, PhD, RN, CWCN, FAAN. Her advice:
  • Moisten the skin to aid in visualizing color change.
  • Ask about pain in the area.
  • Palpate the skin for induration.

Stage 2

Partial-thickness loss of skin with exposed dermis. The wound bed is viable, pink or red, moist, and may also present as an intact or ruptured serum-filled blister. Adipose (fat) and deeper tissues are not visible. Granulation tissue, slough, and eschar are not present. These injuries commonly result from adverse microclimate and shear in the skin over the pelvis and shear in the heel.

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 (like skin tears, burns, abrasions).

Stage 3

Full-thickness skin loss. Full-thickness loss of skin, in which adipose is visible in the ulcer and granulation tissue and epibole (rolled wound edges) are often present. Slough and/or eschar may 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/or bone are not exposed. If slough or eschar obscures the extent of tissue loss, this is an Unstageable Pressure Injury.

Stage 4

Full-thickness skin and tissue loss. Full-thickness skin and tissue loss with exposed or directly palpable fascia, muscle, tendon, ligament, cartilage, or bone in the ulcer. Slough and/or eschar may be visible. Epibole, undermining, and/or tunneling often occur. Depth varies by anatomical location.

If slough or eschar obscures the extent of tissue loss, this is an Unstageable Pressure Injury.

Unstageable Pressure Injury

Obscured full-thickness skin and tissue loss. Full-thickness skin and tissue loss in which the extent of tissue damage within the ulcer cannot be confirmed because it is obscured by slough or eschar. If slough or eschar is removed, a Stage 3 or Stage 4 Pressure Injury will be revealed. Stable eschar (i.e., dry, adherent, intact without erythema or fluctuance) on the heel or ischemic limb should not be softened or removed.

Deep Tissue Pressure Injury

Persistent non-blanchable deep red, maroon or purple discoloration. Intact or non-intact skin with localized area of persistent non- blanchable deep red, maroon, purple discoloration or epidermal separation revealing a dark wound bed or blood-filled blister. Pain and temperature change often precede skin color changes. Discoloration may appear differently in darkly pigmented skin.

This injury results from intense and/or prolonged pressure and shear forces at the bone-muscle interface. The wound may evolve rapidly to reveal the actual extent of tissue injury or may 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 (Unstageable, Stage 3, or Stage 4). Deep tissue pressure injuries do not describe vascular, traumatic, neuropathic, or dermatologic conditions.

Mucosal Membrane Pressure Injury

Mucosal membrane pressure injury is found on mucous membranes with a history of a medical device in use at the location of the injury. These ulcers cannot be staged.

Preventing Pressure Injuries

Because of their cost, finding ways to prevent and more rapidly heal PIs has become a quest for countless wound care providers, clinicians, and technology and product providers. One way to prevent and lower the cost of PIs is to invest in digital measurement and documentation. Digital imaging has earned its reputation as the gold standard in wound documentation. This advanced technology reduces the subjectivity in wound assessments and provides comprehensive, consistent, compliant documentation.

When digital techniques are used, the results are dramatic. For example, Tissue Analytics’ digital photo technology has a 95+% accuracy rate, whereas measuring wounds with rulers is only 40% accurate and subject to significant variabilities.

Digital wound imaging also speeds workflow because it enables clinicians to capture and upload wound images and other documentation, including automated measurements, quickly and easily. Tissue Analytics’ imaging solution has been shown to save five to ten minutes per patient in documentation time, resulting in a minimum of 2.5 hours of charting time saved daily.

This means clinicians are no longer “paper wranglers;” they have extra time to discuss more informed treatment decisions for the patient’s wound outcome management pathway.

Ways to Reduce Cost and Risk

Using digital documentation and assessment technology can substantially reduce the cost of PIs and the risk of fines or penalties. For example, using advanced digital wound care platforms, a large hospital system in the mid-Atlantic reduced HAPIs by 83% and reduced costs from $3.6M to $700k over 6 months. This is far from the only example of reducing cost and risk when it comes to pressure injury.

• After deploying a global surveillance tool for pressure injury prevention, one health system avoided two HAPI lawsuits with estimated litigation costs of $435,000.
• A 650-bed hospital with a 5-star CMS rating launched a comprehensive pressure injury prevention program and reduced PSI-03 scores by 50%. (Note: The PSI-03 metric is defined by CMS as the total number of pressure injuries of stage III, IV (Never Events) ,or unstageable divided by the total number of eligible discharges multiplied by 1000.)
• A major regional hospital streamlined workflow by 57% – saving providers 2.5 hours/day and enabling the department to see an additional 1.2 patients per day, thereby creating efficiencies that also contribute to value-based care (VBC).

Wound management providers who are caring for patients with pressure injuries today face a demanding environment. People are living longer and have more comorbidities, both of which contribute to the chronic nature of PIs. Timely and accurate assessment and documentation supported by the latest technology is essential for managing pressure injuries and ensuring that patients receive the care they deserve.