Rattling sounds due to obstruction of large airways?

Stridor:

- High pitched musical sound

- Occurs during inspiration

- Usually due to laryngeal obstruction

Wheeze:

- Variable pitched musical sound

- Occurs during both inspiration and expiration

- Usually due to bronchial obstruction

Rales:

- Harsh rattling sound

- Occurs during inspiration and expiration

- Usually due to secretions or mucus in the lungs