Stertor, from Latin 'stertere' to snore, and first used in 1804, is a noisy breathing sound like

snoring Snoring is the vibration of respiratory structures and the resulting sound due to obstructed air movement during breathing while sleeping. The sound may be soft or loud and unpleasant. Snoring during sleep may be a sign, or first alarm, of obs ...

.O Cathain E, Gaffey MM
Upper Airway Obstruction
In: StatPearls. StatPearls Publishing, Treasure Island (FL); 2020. It is caused by partial obstruction of the upper airways, at the level of the pharynx and nasopharynx. It is distinguished from

stridor Stridor (Latin for "creaking or grating noise") is a high-pitched extra-thoracic breath sound resulting from turbulent air flow in the larynx or lower in the bronchial tree. It is different from a stertor which is a noise originating in the pha ...

by its pitch. Stertor is low-pitched, and can occur when breathing in, out or both. Stertor and stridor can occur together, such as when adenotonsillar hypertrophy and

laryngomalacia Laryngomalacia (literally, "soft larynx") is the most common cause of chronic stridor in infancy, in which the soft, immature cartilage of the upper larynx collapses inward during inhalation, causing airway obstruction. It can also be seen in olde ...

occur together.

References

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