Definition of decubitus ulcers: tissue ulceration and necrosis that occurs when the local tissues of the body are subjected to long-term pressure, blood circulation is impaired, and the skin and subcutaneous tissues are continuously deprived of blood, oxygen, and nutrients, resulting in the loss of normal function of the local tissues. Decubitus ulcers are not a disease, but a serious complication secondary to certain diseases. Shanghai Deji Hospital General Surgery Department, Zhao Baiqiu, suffers from decubitus ulcers: the elderly, the thin and obese, the paralyzed, the unconscious, the sedated, the edematous, the febrile, the incontinent, the painful, the restrained, the malnourished, the diabetic, the anemic, and those using traction, plaster, and bandages. Causes of disease: 1, local pressure for too long: patients with sensory disorders, motor disorders, prolonged compression of local tissues appear local tissue ischemia, coupled with their own poor nutritional status, the tissue is prone to cause breakage, gradually involving the skin, fat, muscle, etc. 2.Moisture: impregnation of the skin with sweat, urine and stool, etc., stimulates the skin, leading to a decrease in skin resistance, increased skin susceptibility, and the appearance of bedsores. 3.Poor nutritional status: Elderly and frail patients, cachectic patients, patients with long-term wasting diseases and absorption disorders are prone to malnutrition, resulting in low body resistance, massive consumption of fat pads that bear pressure, hypoproteinemia, susceptibility to bed sores, and delayed wound healing. 4. Friction: Minimize friction between long-term bedridden patients and hard objects, and let patients lie on air cushions with ventilation and professional decubitus ulcer prevention. Site of disease: Most often occurs at the bony bulge where there are no muscles or the muscle layer is thin, and where there is a lack of fatty tissue protection and frequent pressure. 1. Supine position: occipital ridge, scapula, elbow, vertebral bulge, sacrococcyge, heel. 2.Side lying position: ear, shoulder, elbow, rib cage, hip, inner and outer knee joints, and inner and outer ankle. 3. Prone position is good for: ear, cheek, shoulder, female breast, male genitalia, iliac crest, knee, and toe. Staging of decubitus ulcers: The formation process is divided into three stages: the erythematous stage, the blistering stage and the ulcer stage, and the symptoms of different stages: 1. If the pressure is removed during this period, the changes disappear within 48 hours. 2.Blistering stage (degree II): blisters of different sizes appear on the pressure area, and the skin becomes red and congested, which does not subside when pressed with the fingers. 3.Shallow ulcers (bedsore degree III): The ulcers do not exceed the whole layer of the skin, and due to the lack of blood supply at the base of the ulcers, they are pale, with edematous granules and running water. 4.Deep ulcers (degree IV of decubitus ulcers): deep fascia and muscles are involved, and the affected tissues are black with necrosis due to ischemia, and the lesions often invade bone due to infection of cells, forming osteochondritis or osteomyelitis. In general, local inflammation with redness, swelling, heat, and pain around the traumatic surface, as well as pus and foul-smelling symptoms, can be identified as signs of local infection, while fever indicates a systemic reaction. In the early stages of decubitus ulcers, the patient or family must pay high attention to the fact that if the triggering factors persist, the pressure sore can be aggravated and the tissue necrosis can occur within a few hours, and once necrosis occurs, the treatment can take as little as 2-3 months or as much as half a year.