Stage 1 Pressure Injury

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.

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Stage 2 Pressure Injury

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) is not visible 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.

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Stage 3 Pressure Injury

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 are not exposed. If slough or eschar obscures the extent of tissue loss this is an Unstageable Pressure Injury.

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Stage 4 Pressure Injury

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.

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Unstageable Pressure Injury

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.

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Deep Tissue Pressure Injury

Intact or non-intact skin with area of persistent non-blanchable deep red/maroon/purple discoloration or epidermal separation revealing dark wound bed or blood-filled blister. Pain and temperature change often precede color changes. DTPI results from prolonged pressure and shear forces at the bone-muscle interface. The wound may evolve rapidly or may resolve without tissue loss. If necrotic, subcutaneous, granulation tissue, fascia, muscle or other underlying structures are visible, this indicates full thickness pressure injury (Unstageable, Stage 3 or Stage 4).

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  • References

    Consortium for spinal cord medicine. Pressure Ulcers Prevention and Treatment following Injury. A Clinical Practice Guideline for Health Care Professionals, Paralyzed Veterans of America 2014;Second Edition:2.

    Gray M, et al. NPUAP Pressure Injury Stages. National Pressure Ulcer Advisory Panel 2016.

    Kruger E, Pires M, Ngann Y, Sterling M, Rubayi S. Comprehensive management of pressureulcers in spinal cord injury: Current concepts and future trends. The Journal of Spinal Cord Medicine 2013;36(6).