NBRC Registered Respiratory Therapist (RRT) Exit Practice Exam

Crepitus reflects subcutaneous emphysema, a palpable crackling sensation caused by air that has escaped into the soft tissues under the skin. This appears as bubbles of air that you can feel beneath the surface, commonly around the chest wall, neck, or face after chest trauma, pneumothorax, or procedures. That palpable subcutaneous air is what crepitus describes. The other options describe different problems: fluid in the pleural space (pleural effusion) causes dull sounds and reduced breath sounds rather than a crackling sensation from under-the-skin air; air in the stomach would present with abdominal symptoms or tympany rather than chest palpation findings; an obstructed airway leads to distress and noisy or absent air movement but not subcutaneous air crepitus.