Which characteristic defines a stage I pressure ulcer?

A stage I pressure ulcer is defined by non-blanchable erythema of intact skin. This means that when pressure is applied to the area, the redness does not fade or turn lighter when the pressure is released, indicating that there is damage to the skin's surface layers, although it remains intact. This is often an early sign of tissue damage caused by prolonged pressure, which can lead to more severe ulcers if not managed properly. Recognizing this stage is crucial for timely intervention and prevention of further skin breakdown.

The characteristics associated with the other stages of pressure ulcers include blister formation, which indicates a more advanced stage; open sores with drainage, which represent further deterioration; and full-thickness skin loss, which signifies grave tissue damage involving deeper layers beyond the skin. Understanding these distinctions is vital for effective assessment and treatment of pressure ulcers.