When touching the skin of a person with subcutaneous emphysema, what can be felt?

The presence of crackling when touching the skin of a person with subcutaneous emphysema is indicative of air trapped beneath the skin. This condition occurs when air leaks into the subcutaneous tissue, often as a result of trauma or injury to the lungs or airways.

When you palpate the affected area, the air bubbles can create a distinctive sensation, often described as a crackling or popping feeling, similar to the sound of popping bubble wrap. This phenomenon occurs because the air accumulates between the layers of tissue, disrupting normal skin tension and creating pockets of gas that respond to pressure changes.

The other sensations mentioned do not accurately describe what is felt in the case of subcutaneous emphysema. Warmth, soreness, and swelling may accompany various injuries or conditions, but they are not characteristic of the specific tactile sensation experienced when air is present in the subcutaneous layer.