Editing Nursing Skills and Procedures (section)

=== Pressure injury staging ===
* Stage 1: intact skin with nonblanchable erythema. In darker skin tones look for a color change compared with surrounding skin plus warmth, firmness, or boggy texture.
* Stage 2: partial thickness loss of dermis, shallow, pink or red moist wound bed, or an intact or ruptured serum-filled blister. No slough, no granulation, no adipose visible.
* Stage 3: full thickness loss with visible adipose tissue. Slough or eschar may be present but does not obscure the depth. Undermining and tunneling may occur. Bone, tendon, and muscle are not exposed.
* Stage 4: full thickness loss with exposed or directly palpable fascia, muscle, tendon, ligament, cartilage, or bone.
* Unstageable: base obscured by slough or eschar so depth cannot be determined.
* Deep tissue pressure injury: persistent nonblanchable deep red, maroon, or purple discoloration, or a blood-filled blister, over intact or nonintact skin.

Application note: stable, dry, adherent eschar on an ischemic heel is not debrided. It acts as a biological cover. The nurse protects it, offloads the heel, and reports changes such as new erythema, fluctuance, drainage, or odor.