The redness of the buttocks after sleeping for a long time is considered to be a bedsore, which is mainly caused by the pressure on the buttocks after lying flat for a long time. Decubitus ulcer is the body of local tissue long-term pressure, blood circulation obstacles, local tissue continuous ischemia, lack of oxygen, lack of nutrition, resulting in the loss of normal function of the skin and caused by limited tissue damage and necrosis, generally the higher the local skin external forces, resulting in decubitus ulcers, the shorter the time required, the local organization of the circulation of the basis of the poorer, the more prone to the formation of decubitus ulcers. Generally, the early stage of decubitus ulcer has the symptoms of skin redness, pain, numbness, etc. If the symptoms are not relieved in time, and the condition aggravates, hard knots, edema, blisters, etc. can be formed locally, and the blisters can be broken to reveal red wounds and so on. It is recommended that patients should pay attention to avoid prolonged bed rest, to move the body more, long-term bed-ridden patients should be appropriate to change position, if necessary, under the guidance of a professional physician, active treatment, so as not to delay the condition.