Distension of tissues beneath the skin by gas or air is called?

• A. subcutaneous emphysema
• B. gangrene
• C. agonal edema
• D. agonal dehydration

Answer: (A)

Subcutaneous emphysema is the distension of tissues beneath the skin by gas or air. It occurs when air enters the subcutaneous layer from chest or neck trauma, surgical procedures, or infections with gas-forming organisms, and you may feel a crackling sensation (crepitus) when touching the swollen area. This air-distended swelling contrasts with edema, which is fluid buildup without air and crepitus, and with gangrene, which is tissue death often with color changes and odor. Agonal terms refer to dying processes and dehydration, which do not describe air collecting under the skin. So the best term for distension of tissues by gas or air is subcutaneous emphysema.