International Board of Certified Lactation Consultant (IBCLC) Practice Exam

Which condition is characterized by a high-pitched inspiratory sound during breathing in an infant?

1. Croup

2. Stridor

3. Wheezing

4. Rales

The correct answer is: Stridor

The condition characterized by a high-pitched inspiratory sound during breathing in an infant is known as stridor. Stridor is a clinical sign that occurs due to turbulent airflow in the upper respiratory tract, typically resulting from some form of obstruction or narrowing in the airway. This high-pitched sound is heard particularly during inspiration, indicating that the air is struggling to pass through a narrowed passage. In infants, stridor can be associated with various conditions, including croup, which is a viral infection that causes swelling in the larynx and can lead to stridor. However, stridor itself is the descriptive term for the sound rather than the condition causing it. Understanding this distinction is crucial since stridor can be present in multiple scenarios. Wheezing, on the other hand, refers to a high-pitched sound produced during expiration, usually due to lower airway obstruction and is more common in conditions like asthma or bronchiolitis. Rales, which are often described as crackling or rattling sounds, occur during inhalation and are typically associated with fluid in the lungs, such as in pneumonia or heart failure. Thus, stridor specifically denotes the high-pitched inspiratory sound, making it the correct answer in this context.