Intensive Care Medicine (ICM) Practice Exam

What can short-lasting percussion in lung examination indicate?

1. Pneumothorax

2. Pneumonia

3. Pleural effusion

4. Emphysema

The correct answer is: Pneumonia

In lung examination, short-lasting percussion sounds can indicate the presence of pneumonia. When a clinician performs percussion, they are assessing the underlying structures of the lungs and the presence of fluid or air in the pleural space. In the case of pneumonia, the lung tissue becomes consolidated due to infection, leading to a denser sound during percussion. This denser sound can be described as a dullness instead of the usual resonance heard in healthy lung tissue. Short-lasting percussion, which may indicate an acute process, is particularly relevant in pneumonia because inflammation and consolidation develop quickly in response to infection. This change in the consistency of lung tissue affects how sound travels through it during clinical examination. In contrast, other conditions present different percussion findings. For instance, a pneumothorax would typically produce hyperresonance due to the presence of air in the pleural space, while pleural effusion creates a dull sound because of fluid accumulation, which might not have a 'short-lasting' percussion characteristic. Emphysema may cause a hyperresonant sound as well, due to the increase in air within the alveoli. Each of these other conditions presents distinct percussion findings, emphasizing the specific relevance of short-lasting percussion in the diagnosis of pneumonia.