Secondary Logo

Journal Logo

Pressure ulcers get new terminology and staging definitions

doi: 10.1097/01.NURSE.0000512498.50808.2b
Department: WOUND & SKIN CARE

New terminology and staging definitions for pressure injuries

By the editors of Nursing2017

THE NATIONAL Pressure Ulcer Advisory Panel (NPUAP) has changed its terminology regarding pressure ulcers and updated the definitions for the stages of pressure injury. The term “pressure injury” replaces “pressure ulcer” in the NPUAP Pressure Injury Staging System. The change in terminology more accurately describes pressure injuries to both intact and ulcerated skin, according to the NPUAP. In the previous staging system, “Stage I” and “Suspected Deep Tissue Injury” described injured intact skin, and the other stages described open ulcers. This led to confusion because the definitions for each of the stages referred to the injuries as “pressure ulcers.”

In addition to the change in terminology, Arabic numbers are now used in the names of the stages instead of Roman numerals, and the term “suspected” has been removed from the deep tissue injury definition. Additional pressure injury definitions include “medical device-related pressure injury” and “mucosal membrane pressure injury.”

A pressure injury is defined as “localized damage to the skin and/or underlying soft tissue usually over a bony prominence or related to a medical or other device. The injury can present as intact skin or an open ulcer and may be painful. The injury occurs as a result of intense and/or 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.”

Pressure injuries are staged to indicate the extent of tissue damage. The stages were revised based on questions received by the NPUAP from clinicians attempting to diagnose and identify the stage of pressure injuries. The six stages are as follows (see Update: Six stages of pressure injury):

Stage 1 pressure injury: nonblanchable erythema of intact skin

“Intact skin with a localized area of nonblanchable 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 don't include purple or maroon discoloration; these may indicate deep tissue pressure injury.”

Stage 2 pressure injury: partial-thickness skin loss 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) isn't visible and deeper tissues aren't visible. Granulation tissue, slough, and eschar aren't present. These injuries commonly result from adverse microclimate and shear in the skin over the pelvis and shear in the heel. This stage shouldn't be used to describe moisture-associated skin damage, including incontinence associated dermatitis, intertriginous dermatitis, medical adhesive related skin injury, or traumatic wounds (skin tears, burns, abrasions).”

Stage 3 pressure injury: full-thickness skin loss

“Full-thickness loss of skin, in which adipose (fat) 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 aren't exposed. If slough or eschar obscures the extent of tissue loss, this is an unstageable pressure injury.”

Stage 4 pressure injury: 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 (rolled edges), 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 can't be confirmed because it's obscured by slough or eschar. If slough or eschar is removed, a stage 3 or stage 4 pressure injury will be revealed. Stable eschar (dry, adherent, intact without erythema or fluctuance) on the heel or ischemic limb shouldn't be softened or removed.”

Deep tissue pressure injury: persistent nonblanchable deep red, maroon, or purple discoloration

“Intact or nonintact skin with localized area of persistent nonblanchable deep red, maroon, or 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). Don't use deep tissue pressure injury to describe vascular, traumatic, neuropathic, or dermatologic conditions.”



Additional pressure injury definitions are as follows:

  • Medical device-related pressure injury (etiology)
  • “Medical device-related pressure injuries result from the use of devices 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.”
  • 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. Due to the anatomy of the tissue, these injuries can't be staged.”
Back to Top | Article Outline


InfoLink. Adv Skin Wound Care. 2016;29(6):248.
    National Pressure Ulcer Advisory Panel. National Pressure Ulcer Advisory Panel (NPUAP) announces a change in terminology from pressure ulcer to pressure injury and updates the stages of pressure injury.
      National Pressure Ulcer Advisory Panel. Pressure injury staging illustrations.
        Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved.