What is a pressure ulcer Pressure ulcers occur when there is a localised area of cellular damage to tissue which was previously viable.
Damage can involve superficial tissue, to multiple tissue layers.
Damage can be caused by extrinsic factors and exacerbated by intrinsic factors. The cause of pressure ulcers in the majority of cases is direct pressure applied to the supporting tissue layers. The ulcers being caused by unrelieved pressure that results in capillary occlusion. Pressure ulcers are found to be more common over bony areas of the body. When the skin and underlying tissue is compressed between bone and a hard support surface, damage to the tissues can occur within two hours, resulting in damage to the microcirculation and ischaemia.