Bronchiolitis is a common lower respiratory tract illness, usually of viral aetiology, affecting infants younger than 24 months of age and is a frequent cause of hospitalisation. It causes airway inflammation, mucus production and mucous plugging, resulting in airway obstruction. Effective pharmacotherapy is lacking and bronchiolitis is a major cause of morbidity and mortality.
Conventional treatment consists of supportive therapy in the form of fluids, supplemental oxygen and respiratory support. Traditionally oxygen delivery is as a dry gas at 100% concentration via low-flow nasal prongs. However, the use of heated, humidified, high-flow nasal cannula (HFNC) therapy enables delivery of higher inspired gas flows of an air/oxygen blend, up to 12 L/min in infants and 30 L/min in children. Its use provides some level of continuous positive airway pressure to improve ventilation in a minimally invasive manner. This may reduce the need for invasive respiratory support thus potentially lowering costs, with clinical advantages and fewer adverse effects.