An airway obstruction is a blockage in any part of theairway. The airway is a complex system of tubes that conveys inhaled air from your nose and mouth into your lungs. An obstruction may partially or totally prevent air from getting into your lungs.Causes of upper airway obstruction include foreign body aspiration, blunt laryngotracheal trauma, penetrating laryngotracheal trauma, tonsillar hypertrophy, paralysis of the vocal cord or vocal fold, acute laryngotracheitis such as viral croup, bacterial tracheitis, epiglottitis, peritonsillar abscess, pertussis.