Definition
Wheezing is defined as the high-pitched whistling sounds, often heard from a distance without the aid of the stethoscope, from partial obstruction of the bronchi and the bronchioles. Predominantly, these are expiratory.
Etiopathogenesis
Partial obstruction of air passages (bronchi and bronchioles) due to causes in the lumen, in the wall or outside the wall, is responsible for producing wheezing. Conditions manifesting with wheezing are listed in Box 26.3.
Differential Diagnosis
Wheezing should not be confused with the following respiratory sounds:
- Stridor: Usually an inspiratory sound secondary to upper airway obstruction (usually in larynx or trachea) of irregular quality produced by oropharyngeal obstruction. Expiratory stridor is infrequent.
- Grunting: Expiratory sound produced by partial closure of glottis. Classically, it is encountered in respiratory distress syndrome (hyaline membrane disease).
- Snoring: It is a low-pitched inspiratory sound usually originating from oropharynx.
- Rattling: Coarse inspiratory sounds which are felt as vibrations when head is placed over the chest as a result of some obstruction in larynx or trachea.
Treatment
Treatment is dictated by the etiological condition. Bronchodilators provide relief by decreasing the bronchospasm.
*Usually, potential asthma cases, needing evaluation and follow-up.
