Fine crackles sound quality is like hair rubbing near the ear and may be heard in congestive heart failure and pulmonary fibrosis. Coarse crackles sound quality is low-pitched and moist it may be heard in pulmonary oedema and bronchitis.

Crackles can be further categorised as coarse or fine. It is commonly heard in the bases of the lung lobes during inspiration. The cause of crackles can be from air passing through fluid, pus or mucus. The sound crackles create are fine, short, high-pitched, intermittently crackling sounds. It may be heard in asthma, emphysema and chronic bronchitis.Ĭrackles are also known as alveolar rales. It is commonly heard in the lungs during expiration. Alternately, what we often refer to as rhonchi is the sonorous wheeze, which refers to a deep, low-pitched rumbling or coarse sound, as air moves through tracheal/bronchial passages in the presence of mucus or respiratory secretions. This refers to the high-pitched, whistle-like sound. The classic wheeze may be referred to as a sibilant wheeze.

This is caused by air passing through an obstructed, narrow airway. The sound of a wheeze is a high-pitched, continuous musical sound. It’s typically loudest over the anterior neck, as air moves turbulently over a partially-obstructed, upper airway. Stridor may be heard in conditions such as croup and foreign body obstruction. The cause of this sound is generally the partial obstruction of the larynx or trachea. Stridor is a continuous, high-pitched, crowing sound heard predominantly on inspiration.

Lung sound locations