Table 1National Pressure Ulcer Advisory Panel/European Pressure Ulcer Advisory Panel pressure ulcer classification

1Intact skin with nonblanchable redness of a localized area usually over a bony prominence. Darkly pigmented skin may not have visible blanching; its color may differ from the surrounding area.
2Partial thickness loss of dermis presenting as a shallow open ulcer with a red pink wound bed, without slough. May also present as an intact or open/ruptured serum-filled blister.
3Full thickness tissue loss. Subcutaneous tissue may be visible but bone, tendon or muscles are not exposed. Slough may be present but does not obscure the depth of tissue loss. May include undermining and tunneling.
4Full thickness tissue loss with exposed bone, tendon or muscle. Slough or eschar may be present on some parts of the wound bed. Often includes undermining and tunneling.
UnstageableFull thickness tissue loss in which the base of the ulcer is covered by slough (yellow, tan, gray, green or brown) and/or eschar (tan, brown or black) in the wound bed
Suspected deep tissue injury—depth unknownPurple or maroon localized area of discolored intact skin or blood-filled blister due to damage of underlying soft tissue from pressure and/or shear. The area may be preceded by tissue that is painful, firm, mushy, boggy, warmer, or cooler compared with adjacent tissue.

Source: European Pressure Ulcer Advisory Panel & National Pressure Ulcer Advisory Panel (2009). Prevention and treatment of pressure ulcers: quick reference guide.1

From: Introduction

Cover of Pressure Ulcer Risk Assessment and Prevention: Comparative Effectiveness
Pressure Ulcer Risk Assessment and Prevention: Comparative Effectiveness [Internet].
Comparative Effectiveness Reviews, No. 87.
Chou R, Dana T, Bougatsos C, et al.

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