Resp 1 Flashcards
what mucosa lines each of the 3 systems?
1:conducting system - pseudostraified columnar ciliated epithelium with goblet cells
2: transitional system: pseudostraified columnar ciliated epithelium - NO GOBLET CELLS
3: exchange system: type 1 pneumocytes & type 2 pneumocytes
Respiratory tract divided into 3 systems:
1:conducting system
2: transitional system
3: exchange system
the nasal cavities are divided by
curled shelves of bone covered by a mucous membrane called turbinates or conchae
air from the nasal cavity can enter the pharynx through openings called
choanae
air can also enter the pharynx through the oral-cavity
what is the pharyngeal diverticulum in pigs’ importance
medication or feed can get impacted here and cause resp problems in the pig
what are air sacs
another upper respiratory adaption - found in birds and some non-human primates
respiratory system functions
-air conduction
- air conditioning (heat + moisture)
- air filtration and immune defence
- smell
- vocalization
congenital components of brachiocephalic airway syndrome
- stenotic nares
- elongated soft palate
- tracheal/laryngeal hypoplasia
the congenital malformations of the upper respiratory tract in brachycephalic animals lead to increased
respiratory effort
prolonged increased respiratory effort leads to secondary acquired malformations, including:
-everted laryngeal saccules
-everted tonsils
-hypertrophied and folded pharyngeal mucosa
-laryngeal edema and collapse
-tracheal collapse
Laryngeal paralysis in horses predominantly affects the
left side of the larynx
why is the left side of the larynx more commonly affected by laryngeal paralysis in horses??
axons of the left recurrent laryngeal nerve are much longer and therefore more susceptible to damage/degeneration
other things that can cause laryngeal paralysis?
anesthesia + hepatic encephalopathy
what does laryngeal paralysis in cases of anesthesia or hepatic encephalopathy look like?
bilateral
horses vs dogs laryngeal paralysis
horses - usually unilateral whereas dogs - usually bilateral
dogs - more likely to be caused by generalized neuromuscular disorders
types of inflammation in upper resp system include (5)
serous rhinitis
catarrhal
purulent
fibrinous
granulomatous
serous rhinitis
red, runny nose producing clear, watery fluid
mild clinical condition, often associated with cold weather/mild irritants (winter walk)
catarrhal inflammation
similar to serous rhinitis but increased serous and mucus secretion
runny nose with abundant thick, clear fluid (like ugly crying)
catarrhal inflammation may be associated with
chronic rhinitis such as idiopathic lymphoplasmacytic rhinitis in dogs (less commonly in cats)
purulent (suppurative) inflammation
neutrophilic exudate, usually accompanied by mucosal necrosis and usually associated with bacterial or less commonly fungal infection
fibrinous inflammation
suppurative inflammation with increased vascular permeability (scrambled eggs texture)
- often associated with bacterial or fungal infection
fibrinous inflammation may form
fibronecrotic membranes (aka diphtheritic membranes) composed of necrotic debris, fibrin, and suppurative inflammation that forms a pseudomembrane adhering to underlying eroded or ulcerated mucosal surface
granulomatous inflammation
usually associated with fungal infection or mycobacteria (cottage cheese or stiff cream cheese type consistency exudate)
often associated with chronic inflammation of some kind or idiopathic
feline calicivirus clinical signs
ocular and nasal discharge, ORAL ULCERS (characteristic lesion of feline calicivirus, NOT common with feline herpes virus), conjunctivitis
there are 2 forms of atrophic rhinitis in pigs
non-progressive atrophic rhinitis (NPAR)
progressive atrophic rhinitis (PAR)
NPAR is caused by
bordetella bronchiseptica REMEMBER SPELLING !!!
NPAR infection causes what clinical signs
mild transient sneezing and nasal discharge
- minimal to no herd health significance
less important than PAR
PAR is due to infection with
pasteurella multicoda
Type _______ strains of Pasteurella multicoda are more often associated with atrophic rhinitis than Type A strains
D
the strains of pasturella multocida causing atrophic rhinitis produce
potent cytotoxins that inhibit bone formation and promote bone resorption - leading to the deformation of the turbinates and the snout
there is often co-infection (PAR) with
bordetella bronchiseptica which may produce a dermonecrotic toxin
progressive atrophic rhinitis is clinically associated with
snout distortion, atrophy, and malformation of nasal turbinates
both types of atrophic rhinitis are frequently
multifactorial and can involve a variety of other pathogens (including viral agents)
- air quality can also influence severity of disease
pasteurella multicoda is not able to colonize the nasal mucosa very well unless the mucosal surface has been breached / ulcerated by another pathogen. This is most commonly done by
toxin-producing strains of Bordetella bronchiseptica
which bacterial strains can be cultured from a nasal swab through PCR
pasteurella and bordetella
diagnosis of PAR requires
toxin detection through PCR or ELISA
because PAR and NPAR can be identical grossly, its essential that
culture be used to distinguish between them
to prove PAR, culture alone is not adequate because there are many strains of P. multicoda that do not produce the cytotoxin, so you MUST
isolate the associated toxin using PCR or ELISA
the mucosa of the conducting system and some of the transitional system is composed of
psuedostratified, ciliated respiratory epithelial cells
the amount of cartilage and smooth muscle surrounding bronchi _______________ as the diameter of the airway gets smaller
decreases
is there cartilage lining bronchioles?
no! but there is smooth muscle, especially in larger bronchioles
bronchioles have ________ cartilage, _________ smooth muscle, ________ glands and mucus cells
no, little, no
do bronchioles have a mucociliary apparatus
NO!
epithelium of the bronchioles has __________ ciliated cells (compared to bronchi)
fewer
do bronchioles or bronchi have more defence mechanisms?
bronchi! Bronchioles do not have any mucociliary apparatus, no goblet cells, fewer ciliated cells, and less structural support (no cartilage)
bronchioles therefore more susceptible to infection
are bronchioles or bronchi more susceptible to collapse?
bronchioles !!!! no cartilage
are type 2 pneumocytes as numerous as type 1 cells?
yes, but because they are not flattened, cover only 5% of the alveolar air surface
what are progenitor cells for type 1 pneumocytes?
type 2 pneumocytes
the vulnerability of the resp system to airborne injury is primarily because of?
- extensive surface area of the alveoli, which are the interface between the blood in alveolar capillaries and inspired air
- the large volume of air passing continuously into the lungs
- the high concentration of noxious elements that can be present in air
club cells (formerly Clara cells) are found in
bronchioles
club cells are involved in
detoxification of xenobiotics (foreign material) via mixed function oxidases
club cells produce protective secretions against
oxidative stress and inflammation
club cells also produce
surfactant
conducting system defence mechanisms
mucociliary clearance, antibodies, lysozyme, mucus, coughing, sneezing
transitional system defence mechanisms
club cells, antioxidants, lysozyme, antibodies
exchange system defence mechanisms
alveolar macrophages, intravascular macrophages, opsonizing antibodies, surfactant, antioxidants
portals of entry into the respiratory system
aerogenous (inhalation), hematogenous (blood-borne), direct extension (penetrating wounds, migrating foreign bodies, etc)
examples of aerogenous agents
virus, bacteria, fungus, toxic gases, pneumotoxicants
examples of hematogenous agents
virus, bacteria, parasites, toxins, and pneumotoxicants
if the pulmonary defences are impaired, then the efficiency of the lung at emilinating bacteria is
greatly decreased
