The clinical grading of pressure ulcers, for example, can be divided into the following degrees: 1. degree I: bruising erythematous phase, where there is no damage to the surface, but the skin is red and the damaged skin is dark red, accompanied by redness, swelling, heat and pain, but those who have not improved by lifting the pressure for more than 30 minutes, this is the acute inflammatory reaction phase. 2. degree II: inflammatory infiltration phase, where the damaged skin is purple-red, and the redness and swelling are enlarged, there are hard nodules under the skin, the skin is thinner, and there is inflammatory exudation, with blisters of varying sizes on the surface, accompanied by pain and necrotic tissue inside. There is also inflammatory exudation, with blisters of varying sizes on the surface, which break down very easily, accompanied by pain, and with necrotic tissue inside. 3. degree III: superficial ulcer stage, where the epidermal blisters break down and can reveal a flushed, red trabecular surface with yellow exudate, and the infection is covered with pus, forming a superficial ulcer with increased pain in the patient. 4. degree IV: necrotic ulcer stage, which is a severe stage of pressure ulcers, where the infection progresses to a deeper level and can be as deep as Bone, there is blackened necrotic tissue, increased purulent secretions, and a foul odor.