Bed sores are categorized by severity, from Stage I (earliest signs) to Stage IV (worst):
- Stage I: A reddened area on the skin that, when pressed, is “non-blanchable” (does not turn white). This indicates that a pressure ulcer is starting to develop.
- Stage II: The skin blisters or forms an open sore. The area around the sore may be red and irritated.
- Stage III: The skin breakdown now looks like a crater where there is damage to the tissue below the skin.
- Stage IV: The pressure ulcer has become so deep that there is damage to the muscle and bone, and sometimes tendons and joints.
Occasionally, reference will be made to a bed sore that is “unstageable.” An unstageable bed sore is usually indicative of a bed sore that has advanced so far that a large area of skin, tissue and bone is involved.
Interestingly, once a bed sore has progressed to a certain point, it can not be improved in terms of level of severity. For example, even after a stage IV bed sore has begun the healing process, it is still considered to be a stage IV bed sore.