Florida State Paramedic Practice Exam

What is the primary cause of stridor when assessed in a patient?

1. Obstruction of the windpipe

2. Fluid accumulation in the lungs

3. Bronchial spasms

4. Cardiac distress

The correct answer is: Obstruction of the windpipe

Stridor is a high-pitched, wheezing sound resulting from turbulent airflow in the upper airway, usually indicating an obstruction. The primary cause of stridor is obstruction of the windpipe, which can occur due to various reasons, such as swelling from an allergic reaction, infections like croup or epiglottitis, foreign body aspiration, or tumors. When there is a partial obstruction in the upper airway, the airflow can generate the characteristic sound of stridor as it passes through a narrowed space. Other conditions like fluid accumulation in the lungs primarily lead to different respiratory sounds, such as crackles, rather than stridor. Similarly, bronchial spasms are usually associated with conditions such as asthma and result in wheezing sounds in the lower airways, while cardiac distress typically presents with different symptoms unrelated to stridor. Thus, obstruction of the windpipe is the key factor in the presence of stridor, making it the correct answer.