L22 Disease of Lung Parenchyma I Flashcards
What cells produce surfactant
Type II oneumocutes
Why doesn’t surfactant accumulate in the lungs
its eaten by macrophages and/ or recycled by the type IIs
What are the major functions of surfactant
lowers surface tension of alveoli so don’t collapse
Agglutination & opsonisation of infx
binds endotoxin
anti-oxidant
What species have grossly lobulated lungs
cows, pigs
Which species have the least lobulated lungs
Cats & dogs
What are some causes of foetal pneumoainsdf
hypoxia > meconium in amniotic cavity > aspiration > transient bronchopneunkoaisnd
placenta infection
What is neonatal hyaline dz
surfactant dysfunction
lung collapse
reinflation damages type I & club –> inflammation –> hyaline membranes formed from fibrin
What are the major mechanisms causing atelectasis in animals?
dependant hypostatic atelectasis from prolonged lat recumbency e.g. horse
congenital foetal atelectasis (e.g. obstruction)
Compression
Obstructive
What will eventually happen to an atelctatic lung if the stimulus is not removed ?
local hypoxia > inc vascular permeability > oedema > fibrosis
What is alveolar emphysema
damage to alveolar walls causing distentision of air spaces
What species/ pathogeneses often see emphysema
horses w heaves
what does alveolar emphysema look like grossly
crepitant, paler, bubbly, raised areas
What is bullous emphysema ?
air bubbles coalesce to form bullae
What is interstitial emphysema?
air from ruptured alveoli close to terminal bronchioles
