Introduction to pressure injuries

Pressure injury is localised tissue damage usually over a bony prominence from pressure (causing tissue compression), often in combination with shear (causing tissue deformation). Pressure injury is caused by prolonged pressure on the skin or tissues from an underlying surface. Chair or bed surfaces cause the majority of pressure injuries. Devices such as casts and splints, tubing, straps and clothing can also cause pressure injury.

Additional pathologies contributing to a pressure injury include reperfusion injury (tissue damage as blood flow returns after a period of ischaemia) and extremes of skin moisture and temperature (the microclimate) at the point of contact with a surface.

Primary risk factors for a pressure injury include reduced mobility (eg inability to change body position independently), or reduced sensory perception (either from reduced sensation or reduced conscious state).

Secondary risk factors for a pressure injury include macerated or moist skin (eg from incontinence), advanced age, malnutrition, poor perfusion and oxygenation, severe illness, increased body temperature, shear (sliding) forces and friction.

Common sites of pressure injury include the area over the sacrum, ischial tuberosities, greater trochanters, heels and malleoli. Pressure injury can also occur on other areas, including the back of the head (occiput), vertebral spinous processes, ears, elbows and toes.

Timely assessment and intervention is crucial in pressure injury prevention and management.