What type of sounds are crackles during a respiratory examination?

Crackles are classified as discontinuous popping sounds that occur in the respiratory system. They are typically heard during inspiration and can be associated with conditions such as pneumonia, bronchitis, or congestive heart failure in canines. The nature of crackles stems from the sudden opening of collapsed airways or the movement of fluid in the alveoli, leading to these characteristic sounds.

This type of sound is distinctly different from continuous sounds, which would be more prolonged and machine-like, such as wheezes. High-pitched whistling sounds are generally indicative of constricted airways, and subtle rustling noises might represent normal breath sounds or very soft contexts in lung examination. Thus, crackles stand out as random, discrete events that indicate specific pathological processes within the lungs.