Sources: A Manual Of Peroral Endoscopy And Laryngeal Surgery

If the foreign body completely obstructs a main

bronchus, preventing both aeration and drainage, such rapid

destruction of lung tissue follows that extensive pathologic changes

may result in a few months, or even in a few weeks, in the case of

irritating foreign bodies such as peanut kernels and soft rubber. Very

minute, inorganic foreign bodies may become encysted as in

anthracosis. Large objects, however, do not become encysted. The

object is drawn down by gravity and aspirated into the smallest

bronchus it can enter. Later the negative pressure below from

absorption of air impacts it still further. Swelling of the bronchial

mucosa from irritation plus infection completes the occlusion of the

bronchus. Retention of secretions and bacterial decomposition thereof

produces first a drowned lung (natural passages full of pus); then

sloughing or ulceration in the tissues plus the pressure of the pus,

causes bronchiectasis; further destruction of the cartilaginous rings

results in true abscess formation below the foreign body. The

productive inflammation at the site of lodgement of the foreign body

results in cicatricial contraction and the formation of a stricture at

the top of the cavity, in which the foreign body is usually held. The

abscess may extend to the periphery and rupture into the pleural

cavity. It may drain intermittently into a bronchus. Certain

irritating foreign bodies, such as soft rubber, may produce gangrenous

bronchitis and multiple abscesses. For observations on pathology (see

Bibliography, 38).