What is the expected breath sound when there is fluid in the alveoli?

When fluid accumulates in the alveoli, the expected breath sound is crackles, also known as rales. This phenomenon occurs because the presence of fluid disrupts the normal airflow and causes the alveoli to collapse and then open during respiration, creating a popping or crackling sound. This is often indicative of conditions such as pulmonary edema or pneumonia, where fluid infiltrates the lung tissue.

Crackles are typically heard during inspiration and can vary in intensity and duration depending on the amount and location of fluid present. The sound is not associated with obstruction but rather with the reopening of collapsed airways or the movement of fluid in the alveolar spaces. Understanding these sounds is crucial for EMTs to assess and manage respiratory distress effectively.