Wound Staging After Eschar Removal

Understanding Wound Depth and Staging

The staging system is based on the depth of tissue loss/destruction, not simply what tissue layer is currently exposed or visible, and wounds covered by eschar or slough are classified as "unstageable" because the extent of tissue damage is obscured by the necrotic tissue 1, 2, 3.
Once the eschar is removed, the wound reveals its true depth and can then be staged as either Stage III or Stage IV, with the key principle being that the true depth must now be determined by what tissue layers were actually destroyed, not just what is currently visible 1, 2, 3.

To determine the actual depth of a wound, a sterile, blunt metal probe should be used, looking for exposed or palpable subcutaneous fat, muscle, tendon, ligament, or bone, as the presence of these structures indicates deeper tissue loss 1, 2, 3.
Stage II wounds are characterized by partial-thickness loss of dermis presenting as a shallow open ulcer with a viable red-pink wound bed without slough, and no subcutaneous fat, muscle, or bone visible or destroyed 1, 2, 3.
Stage III wounds involve full-thickness tissue loss exposing subcutaneous fat, with bone, muscle, and tendon not visible or exposed, and slough or eschar may have been present before removal 1, 2, 3.
Stage IV wounds are characterized by full-thickness tissue loss with exposed or palpable bone, muscle, ligament, or tendon, and slough or eschar may have been present before removal 1, 2, 3.

The location of the wound, such as over bony prominences, and the chronicity of the wound, should be considered when assessing the depth and stage of the wound, as these factors can influence the likelihood of deeper tissue destruction 1, 2, 3.
A common pitfall is assuming dermis exposure automatically means Stage II, when in fact the wound may have had full-thickness destruction with deeper tissues already lost or debrided, emphasizing the need to probe the wound to assess true depth 1, 2, 3.
Failing to probe the wound, especially in pressure injuries where tunneling or undermining may be present, can lead to inaccurate staging, and palpable bone indicates Stage IV regardless of what is visible on the surface 1, 2, 3, 4.