What is a pressure ulcer?
Lesions caused by unrelieved pressure that results in damage to underlying tissue. They are caused by a deficiency of blood supply to the tissue (ischemia). Friction can also cause shearing of the skin. For instance a sheet may remove superficial layers of the skin making it more prone to breakdown. Factors that can contribute are immobility, inadequate nutrition, edema, fecal or urinary incontinence (maceration causes softening of tissue by prolonged wetting, fecal matter contains enzymes that may break down the skin), excessive body heat (increases the body's metabolic rate, increasing the need for cellular oxygen), and advanced age (decrease pain sensation of pressure and skin integrity)(482)