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Skin Integrity and Pressure Injuries


The assessment of an individual with a pressure injury is the basis for planning treatments, evaluating treatment effects and communicating with other caregivers” (AHCPR, Executive Summary #15 p 3). One key piece of this assessment is the staging of the pressure injury to classify the degree of tissue damage observed by the clinician (AHCPR, Executive summary # 15 1992). In 1989, a staging system based on the original work of Shea in 1975, was refined and recommended by the National Pressure injury Advisory Panel (NPIAP 1989). In 2016 as knowledge of the many factors associated with pressure injury formation emerged, two additional stages (Deep Tissue Injury [Suspected] Stage and Unstageable) were added to the original four to form the current six descriptive stages (NPIAP 2016).

Since 1989, this staging system has been used consistently in the literature and is widely supported (AHCPR 1992; Consortium of Spinal Cord Medicine 2000; Registered Nurses Associated of Ontario 2002; Houghton et al. 2013). However, authors of earlier studies have used numerous ways of documenting the severity of pressure injuries making it challenging to draw parallels between older and newer studies.

Stage Description
Deep Tissue Injury (Suspected) Stage Purple 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 as compared to adjacent tissue.
Stage 1 Intact skin with non-blanchable 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.
Stage 2 Partial-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.
Stage 3 Full-thickness tissue loss. Subcutaneous fat 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
Stage 4 Full-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.
Unstageable Full-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.
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