Emergency Medical Technician (EMT) Basic Certification Practice Exam

Crackles or rales are typically associated with which situation in the lungs?

1. Fluid surrounding or filling the bronchioles/alveoli

2. Blockage of air passages

3. Inflammation of the pleura

4. Normal air flow through alveoli

The correct answer is: Fluid surrounding or filling the bronchioles/alveoli

Crackles, also known as rales, are abnormal lung sounds often heard during auscultation and are typically associated with fluid accumulation in the lungs, which can occur in conditions like pneumonia, heart failure, or pulmonary edema. When fluid surrounds or fills the bronchioles and alveoli, it disrupts normal airflow, leading to the characteristic popping or crackling sounds as air passes through these fluid-filled areas. This is why answer A is the most accurate choice in identifying the situation in the lungs associated with crackles. In contrast, blockage of air passages is generally associated with wheezing or stridor, indicative of restricted airflow due to obstruction, rather than the presence of fluid. Inflammation of the pleura can lead to pleuritic pain and may create different respiratory sounds but is not directly linked to the crackling sounds produced by fluid in the lung tissues. Lastly, normal airflow through the alveoli would not produce crackles, as they denote abnormal lung conditions rather than healthy lung function.