Which stage is defined by full-thickness tissue loss with the base of the ulcer covered by slough or eschar?

• A. Stage 2
• B. Stage 3
• C. Stage 4
• D. Unstageable

Answer: (D)

This item is about wound staging and how depth and the wound bed determine the stage. When there is full-thickness tissue loss, you can’t determine how deep the injury goes if the base is covered by slough or eschar. That obscured depth is what defines an unstageable wound. Slough is soft, often yellow or gray dead tissue, while eschar is dry, dark, leathery necrotic tissue. Because the base isn’t visible, you can’t tell whether deeper structures are involved, so the wound is classified as unstageable until the slough or eschar is removed and the true depth is revealed. Once debridement exposes the underlying tissue, the wound would then be staged as III or IV depending on what structures are involved (subcutaneous tissue versus muscle/bone, etc.).