Pressure injury is best defined as

• A. Localized tissue damage over a bony prominence or under a medical device
• B. A blister caused by a burn
• C. A minor scrape
• D. A normal skin irritation from moisture

Answer: (A)

Pressure injury refers to localized damage to the skin and underlying soft tissue that occurs when external pressure over a bony prominence (or under a medical device) reduces blood flow, leading to tissue ischemia and death. The defining point is that the damage comes from sustained pressure in those vulnerable areas, not from a burn, a simple scrape, or skin irritation from moisture. Friction and shear can worsen the injury, but the characteristic feature is tissue damage tied to pressure over a bone area or beneath a device. For example, prolonged laying in one position or a device pressing against the skin can cause this type of injury even if the skin initially looks only mildly red.