Clinically encountered decubitus ulcers are a process from mild to severe and are divided into the following four stages: 1. the skin is intact and red, with clear boundaries with the surrounding skin, the pressure reddened area does not turn white with finger down pressure, local redness, swelling, heat, pain, numbness, the skin color cannot return to normal after removal of pressure; the color is different from the surrounding tissues, often confined to the site of the bony prominence, this stage requires avoiding pressure and strengthening nutrition; 2. with further progress there will be local epidermal defects, which belong to the second stage, also known as the inflammatory infiltrative stage, the skin surface appears red at the base of the rupture, but there is no crusting, or it can be intact or ruptured blood blisters, the second stage needs to protect the skin, avoid infection, strengthen nutrition, small blisters can be self-absorbed, large blisters need to be sterilized by aseptic suction, and finally the appropriate amount of bandaging; 3. On the basis of the second stage if there is no active intervention, the condition will further aggravate and the decubitus ulcer deepens, manifesting as a full skin defect, subcutaneous fat can be observed to be exposed, there is necrotic tissue shedding, but the depth of necrotic tissue is not clear, there are muscles, tendons, bone, etc. not yet leaking out, there are crusts and subcutaneous subterranean tunnels, this phase should keep the local clean and dry, cover the wound with ulcer ulcer paste and other dressings to promote wet wound healing; 4, with the aggravation of the disease will further deepen into Stage IV, manifesting as skin loss, accompanied by muscle and tendon fracture exposure, localized necrotic tissue shedding alternatively, often with crusts and subcutaneous tunnels, Stage IV is a very serious pressure sore, this stage should be given by a professional surgeon for debridement surgery to remove necrotic tissue, keep drainage open, and require comprehensive treatment, including surgical treatment to heal; 5, unstageable manifesting as full skin loss, the ulcer base will have The scab at the bottom can be shallow or deep, shallow to the extent of stage II, deep to stage IV, so it is defined as unstageable.