Bronchiolitis is an acute respiratory illness caused by several viruses, most commonly respiratory syncytial virus. Other pathogens implicated include parainfluenza viruses, rhinoviruses, influenza viruses, and metapneumoviruses. These viral infections inflame the smaller airways, causing increased mucous secretion, cell sloughing, submucosal edema, small airway narrowing and obstruction. Hypoxia is due to an obstructive shunt, causing ventilation/perfusion […]