What type of stridor indicates an intrathoracic compression of the trachea?

Expiratory stridor is indicative of intrathoracic compression of the trachea. This type of stridor occurs due to the narrowing of the airway during expiration, which can be associated with various conditions that cause obstruction or compression within the thoracic cavity.

When there is an obstruction affecting the airflow during expiration, the high intrathoracic pressures during this phase lead to turbulent airflow, resulting in a wheezing or stridor-like sound. Conditions that can lead to this phenomenon include tumors, foreign bodies, or other masses inside the thoracic cavity that apply pressure to the trachea, resulting in an expiratory stridor pattern.

In contrast, inspiratory stridor is typically associated with upper airway obstruction, such as croup, epiglottitis, or allergic reactions, where the narrowing occurs predominantly during inspiration. Mixed stridor includes components of both inspiratory and expiratory stridor and is seen in more generalized airway compromise, while unilateral stridor may suggest localized obstruction or pathology affecting only one side of the airway, but does not specifically indicate intrathoracic compression.

Understanding these distinctions is critical for diagnosing and managing airway complications effectively in emergency medicine.