Barotrauma is best described as which of the following?

• A. A skin condition caused by pressure
• B. Tissue injury from pressure change; middle ear and sinuses are most commonly affected
• C. A disease of the lungs due to infection
• D. A sensation of pressure in the chest

Answer: (B)

Barotrauma is tissue injury caused by a change in ambient pressure. The pressure inside air-filled spaces must match the outside world, and when equalization fails, a pressure difference builds across the membranes. The middle ear and sinuses are most commonly affected because they rely on small passages (the Eustachian tubes and sinus ostia) to balance pressure. During ascent or descent, if these pathways are blocked or don't open, the external pressure change causes the gas inside these spaces to push or compress the membranes, leading to pain, possible rupture of the tympanic membrane or sinus walls, and sometimes hearing changes or bleeding. The other descriptions describe conditions not caused by pressure changes in these spaces, so they don’t fit barotrauma.