Pressure ulcer refers to the skin and subcutaneous in a certain intensity, the duration of a certain period of time pressure, friction or shear force alone or under the joint action, due to the skin vascular and lymphatic system damage caused by the cell and tissue necrosis as the characteristics of the rupture of the injury. Etiology: 1, direct cause: pressure, shear, friction, the combination of the three can lead to microcirculation occlusion, resulting in tissue ischemia, which in turn causes inflammation and hypoxia occurs, leading to tissue necrosis and ulcer formation. Inherent etiology: Sensory-motor and consciousness disorders, malnutrition, improper care. Pressure ulcers occur in any part of the body where soft tissues are under pressure, and usually in the skin on the surface of bony protruding parts of the body. Stages of pressure ulcers: Stage I: Usually, the skin on the bony prominence appears red spots that do not turn white when pressed, but the skin is intact. Stage II: superficial open ulcers with partial loss of dermis, with a dry or shiny pink base free of necrotic tissue; they may also appear as intact skin or as broken serous-filled blisters. Stage III: total skin loss, subcutaneous fat layer is visible but bone, tendon or muscle has not been exposed, necrotic tissue may be present but the depth of tissue loss is unknown, this stage may also include fistulas and tunnels. Stage IV: total tissue loss with exposure of bone, tendon or muscle, the wound may be covered with necrotic tissue and crusts, there are usually fistulas and tunnels, or even ulceration deep into the muscle and supporting system (e.g., fascia, tendon, joint capsule, etc.) and osteomyelitis may occur. Non-stageable: the defect involves the entire tissue layer, but the wound bed of the ulcer is actually completely covered by necrotic tissue or/and crust (yellow, gray, black, gray-green, or tan). The depth and staging of the ulcer cannot be determined unless the necrotic tissue or/and crust is completely removed to expose the base of the wound. A solid heel crust (dry, tightly adherent, and intact with no redness, swelling, or fluctuating sensation) corresponds to the body’s “natural (biological) protective barrier” and should not be removed. Treatment: I. Systemic comprehensive treatment: improve the nutritional status, improve the function of the heart, lungs and kidneys, actively treat the primary disease, anti-infective treatment, release muscle spasm, do not use or be careful to use some of the drugs that are not conducive to the recovery of the wound, such as sedatives. Second, the etiology of treatment: 1, eliminate local pressure: regular turning Q2h, transfer, change position; 2, the use of decompression devices. Third, pressure ulcer wound treatment: 1, clean and change the medicine, 2, surgical treatment. Fourth, rehabilitation treatment: 1, foam dressing, 2, phototherapy (ultraviolet light), 3, ultrashort wave, 4, whirlpool bath (clean wound pressure ulcers are not applicable).