A patient with blunt chest trauma and asymmetrical chest wall movement MOST likely indicates:

• A. Several ribs broken in numerous places
• B. Shallow breathing secondary to severe pain
• C. Decreased air movement into one lung
• D. Accumulation of blood in both lungs

Answer: (C)

When one side of the chest moves less than the other after blunt chest trauma, it points to a problem ventilating that side. The most likely cause is a pneumothorax, where air collects in the pleural space and the affected lung collapses, so less air enters that lung during inspiration. The result is asymmetric chest expansion and reduced air movement on the side with the pneumothorax. This is distinct from simply having several broken ribs or shallow breathing from pain, which don’t by themselves produce unilateral loss of ventilation. If both lungs were equally affected (as with bilateral contusion or large bilateral blood collection), you’d expect a more global pattern rather than a single side being compromised.