Respiratory Flashcards
(28 cards)
what are the three divisions of the respiratory tract? which ones are lined with resp epithelium
conducting (trachea, carina, extra/intra pulmonary bronchus)
transitional (bronchioles)
exchange (alveoli)
first 2 - conducting and transitional lined with resp epithelium
is the URT or LRT lined with cilia
URT
why is the lung unlikely to infarct
due to dual blood supply
defense mechanisms of the URT
bacterial flora
mucus (goblet cells)
cilia
bronchial-associated lymphoid tissue (BALT)
IgA
sneeze/cough
defense mechanisms of LRT
fluid
pulmonary alveolar macrophages (main defense)
alveolar surfactants
IgG
what species have pulmonary intravascular macrophages (PIMs)
ruminants
horses
pigs
cats
what are defense mechanisms against blood-borne agents in dogs/rodents/humans and ruminants/horses/pigs/cats
dogs/rodents/humans use kupffer cells & splenic macrophages
ruminants/horses/pigs/cats use PIMs
most vulnerable part of resp tract to airborne pathogens
bronchio-alveolar junction
3 portals of entry
- aerogenous (inhalation, most common)
- hematogenous (blood)
- direct extensions (penetrating injury)
3 causes of ciliary dysfunction
- congenital ciliary dyskinesia (most common in dogs)
- environmental
- infectious
response of UR mucosa to injury
when will ciliated epithelium repair?
ACUTE: decreased cilia, increased goblet cells & inflammation result in impaired mucociliary clearance
Chronic: squamous metaplasia, goblet cell hyperplasia, fibrosis
repairs if basement membrane is intact, if not it will scar
alveolar response to injury
type II hyperplasia (type I cells replaced by hyperplastic type II cells (not good for gas exchange))
hyaline membranes
fibrosis
bronchopneumonia morphological patterns and route of entry
cranioventral
aerogenous
interstitial pneumonia morphological patterns and route of entry
diffuse, dorsocaudal
edema, emphysema, rubber/meaty texture, fibrosis if chronic
aerogenous or hematogenous
embolic pneumonia morphological pattern and route of entry
multifocal
hematogenous
most common sources are hepatic abscesses, infected jugular thrombosis, or valvular endocarditis (right)
granulomatous pneumonia morphological pattern and route of entry
well circumscribed, variably sized, firm nodules, can be mineralized
random distribution
aerogenous or hematogenous
main differential is neoplasia
what is associated with a bilateral cranioventral lobular pattern
suppurative bronchopneumonia
bacterial, aerogenous
what is associated with a more severe/serious than suppurative and has a lobar pattern
fibrinous bronchopneumonia
lung worms often give what pattern in the lungs
dorsocaudal
what type of respiratory failure will pleural effusion (hydrothorax, hemothorax, pyothorax, chylothorax), pneumothorax or masses cause
restrictive respiratory failure
what type of respiratory failure will obstruction of movement of air in airways or alveoli or reduced elasticity of lung parenchyma cause
obstructive respiratory failure
common tumors that metastasize to lungs in dogs
hemangiosarcoma of right auricle
mammary
melanoma
lymphoma
adrenal carcinomas
thyroid carcinomas
common tumors that metastasize to lungs in cats
mammary
vx site fibrosarcomas
common tumors that metastasize to lungs in cow
uterine carcinomas
