Which statement best explains how pressure-relieving surfaces reduce tissue injury risk?

• A. They immobilize the patient
• B. They increase heat generation
• C. They distribute pressure over a larger area to reduce ischemia
• D. They eliminate friction completely

Answer: (C)

Pressure-relieving surfaces help by redistributing body weight so pressure is spread over a larger area, which reduces the risk of tissue ischemia. When soft tissues are pressed firmly against a surface, capillary blood flow can be cut off in that spot, leading to ischemia and potential tissue damage. By increasing the contact area, these surfaces lower the peak pressure at any one point, helping maintain blood flow to the tissues and prevent injury.

The other statements aren’t correct: immobilizing the patient doesn’t address pressure points; increasing heat generation isn’t a goal and isn’t how these surfaces work; and friction isn’t completely eliminated—while some reduction in shear can occur, it isn’t nullified, and the key protective effect comes from pressure redistribution.