Pathology of the Respiratory System

upper airway (air entrance)

lower airway (tubes that move air deeper)

lung (air exchange)

What are the three major divisions of the respiratory system?

nasal cavity

paranasal sinuses

nasopharynx

gets the air ready before it goes straight to the lungs I.e. warms it, filters, adds moisture

What does the upper airway consist of? (3)

what is the purpose of this area of division?

larynx

trachea

bronchi

bronchioles

these are the tubes that move air deeper

what does the lower airway consist of? (4)

what is the purpose of this area of division?

bronchi

bronchioles

alveoli

air exchange

what do the lungs consist of? (3)

what is the purpose of this area of division?

thoracic cavity

thoracic cavity

mediastinum

this cross section shows the intricate anatomy of the respiratory system and the anatomic associations of w/ the components of the ______ ______.

this intricate association is important to consider because diseases affecting the _____ ____ or ___________ may also impact the respiratory system

thoracic wall, mediastinum

It is important to remember that diseases affecting the _________ and _________ may also impact the respiratory system.

trachea

primary bronchi

2ndary lobar bronchi

tertiary segmental bronchi

bronchiole

respiratory bronchioles

alveolar ducts

alveolar sacs

alveoli

The respiratory tree is the branching system of airways within the lungs.

It starts from the ____

,which splits into 1°___________, then 2°________ and 3°__________.

these bronchi continue into smaller ________-> ____________ then even smaller into __________, __________ and finally ending in ________.

alveoli

what are the sites of gas exchange?

resistance

With each division in the respiratory tree, there is increased ________, which is important to remember in upper resp. diseases and pneumonia cases.

conductive/ transitional system

gas exchange system

vascular system

the three practical subdivisions of the respiratory system are:

conductive system

Which practical subdivision includes: nasal cavity, turbinates, paranasal sinuses, nasopharynx, larynx, trachea, bronchi

nasal cavity

turbinates

paranasal sinuses

nasopharynx

larynx

trachea

bronchi

What does the conductive system include? (name like 4 of the 7)

humidifies, warms, filters

The conductive system ________, ________ and _______ inspired air.

50-75

the conductive system accounts for ______-_________% of total respiratory resistance

(aka most of the work of breathing occurs here bc air is squeezed through the nose into small diameters, increasing resistance)

Turbinates

__________: Curved or scroll shaped bony structures protruding from the lateral walls and septum of the nasal cavity

warming, humidifying, filtering

regulating nasal airflow

turbinates aid in _______, ________, and ______ inspired air as well as regulating _____________________

impaction of inhaled particles

(think such windy/bendy area is going to get things stuck in it, this is why when gunk is impacted, the reasoning for sneezing)

turbinates are also a major site of what?

paranasal sinuses

___________________: Air filled cavities in the facial bones

- decrease weight of the head (makes the head lighter, therefore easier to hold up)

- auditory (vocal resonance/ echo chambers)

- buffer against facial trauma (air cushions blows)

- insulate structures from temperature changes

What are the four functions of the paranasal sinuses?

doesn't drain well.... the openings close..... sinusitis

Because there are only small openings that communicate between the paranasal sinuses and the nasal cavity, what does this mean happens when the sinuses are inflamed?

vasodilation

_______________ is the hallmark of inflammation

horse

What species has six pairs of paranasal sinuses—the frontal, sphenopalatine and maxillary sinuses, and the dorsal, middle and ventral conchal sinuses

horses

molar roots are under the maxillary sinus so dental disease easily affects here

the maxillary sinus is specific to?

also, where does this sinus reside making what disease common here?

sinusitis

_____: refers to inflammation or infection of one or more of the paranasal sinuses

primary

[primary/secondary] sinusitis is defined as an infection in the sinus, usually bacterial in origin, which results in a buildup of pus within the sinus

secondary

[primary/secondary] sinusitis is an infection of the paranasal sinuses as a result of another primary cause, such as tooth root infection, bone fracture, or sinus cyst

secondary

Is primary or secondary sinusitis more common?

last four cheek teeth, the roots are within the maxillary sinuses

What are most likely to cause a secondary sinusitis in horses? And why?

nasopharynx

______________:Mediates air passage from the nasal cavity to the larynx (connects the nose to the larynx)

eustacian tubes

middle ear

pressure equilibration

the nasopharynx is also the site where the ____________ connect to the _______ and allows for _______________

security checkpoint

immune cells

lympoid nodules/ MALT

the nasopharynx also acts as a __________ _______ as it is packed with ______ _______. specific aggregates of these immune cells are aka __________/ _______

lymphoid nodules, initiator and effector, pathogens

respiratory immunity in the nasopharynx is due to a large aggregate of ____________ in the submucosa. It acts as both a ______ and _______ site, and as a primary site for the colonization of ________>

larynx

_____________: separates the intestinal and respiratory tracts (its a "traffic cop" deciding air-> trachea, food-> esophagus)

is also and organ of phonation

aspiration of ingesta

increased airway resistance

Dysfunction of the larynx can lead to ____________

Narrowing of the larynx can lead to _________

c-shaped cartilaginous rings

the trachea is supported by _________ which maintain rigid structure and lumen size

main stem bronchi

the trachea divides into what?

mainstem bronchi

__________: is the terminal division of the trachea and entry into the pulmonaryy parenchyma

inversely, increase

diameter of the bronchi and resistance are ______________ related... so as diameter decreases, resistance will [increase/decrease]

air delivery

gas exchange

the transitional system is the area where ____ delivery transitions into _____ ______

(this zone includes very small brocnhi, bronchioles; and with each division, diameter decreases and resistance increases)

alveolar spaces

Where does air deliver transition into gas exchange?

bronchioles

_________: "are the small squishy air tubes before the air sacs". they are not supported by cartilage, so the diameter canchange with lung inflation

false; they have no cartilage so the diameter can change with lung inflation

true/false: bronchioles are supported by cartilage so that their small size doesn't change with changes in airflow

small, high

large, low

aka as a functional unit, there are thousands of bronchioles creating a large surface area

individually, bronchiole diameter is _____ and resistance is ________. But as a functional unit, cross sectional area is ______ with ______ resistance... what does this mean?

true

true/false: widespread damage is necessary to increase resistance to airflow in the bronchioles

its there is very little peribronchiolar connective tissue (so it doesn't limit the inflammation)

bronchioles are a common site of inflammation/ impaction... why?

acini

gas exchange occurs in the _______

respiratory bronchioles, alveolar ducts, alveolar space

the acini consists of branching ______ into _______ and _______

fluid accumulation, exudate

damage to the acini will lead to ________ or _______ filling the alveolar spaces or interstitium

acinus

the fundamental functional unit of gas exchange in the lung is the?

blood gas interface

where oxygen and carbon dioxide transfer occurs between air and blood.

gas exchange

respiration

the acinus is a complex, branching structure maximizing surface area for _____ _____, AND forms the crucial interface for ______.

ventilation, perfusion, diffusion

Gas exchange happens over thin barriers through ________ (breathing), _________(blood flow), and ________ (moving gases down their pressure gradients)

terminal bronchiole, alveolar ducts, alveoli

The mammalian gas exchange system originates with each _____________, opening into ________ and a collection of __________

O2

CO2

4microns

the alveolar wall is paper-thin, allowing ____ and _____ to cross easily. its estimated to be about _______ thick

4

hypoxic

It is important to note that the entirety of the alveolar wall is approximately _____ microns thick.

PATHOLOGY ALERT: if the alveolar wall gets thicker, inflammed, filled with fluid, oxygen cannot cross and the animal becomes _____

- type I pneumocyte (thin flattened cells on the surface important for diffusion)

-type II pneumocyte (cubodial cells in the corners producing surfectant)

- basment membrane

- capillary endothelim

what is in the alveolar wall (wall important for gas exchange) (4)

capillaries

Alveoli are wrapped in a dense network of ____________, creating an enormous surface area for gas exchange

pores of Kohn

Adjacent alveoli have connections via small openings, called _______, that allow for collateral airflow and equalization of pressure between alveoli

increased surface area of the membrane

Increased alveolar pressure difference (PA-Pa)

Increased solubility of the gas

Decreased membrane thickness

What four things can increase the diffusion of gas across alveolar membranes?

bronchial circulation

pulmonary circulation

the vasculat system is also of importance not just for gas exchange but bc they lungs must be nourished too. there are two arterial supplies to the pulmonary system, these being __________ and _________

bronchial

________: circulation that arises from the thoracic aorta (oxygenated) and intercostal arteries. supplies the trachea, to the bronchi, to the respiratory bronchioles

pulmonary

_____________: circulation that arrives via the pulmonary artery (unoxygenated) from the right heart. the circulation for gas exchange

bronchial circulation

Which of the two arterial supplies to the pulmonary system brings OXYGENATED blood to the lung tissue to keep it working?

pulmonary circulation

Which of the two arterial supplies to the pulmonary system brings UNOXYGENATED blood to the lung tissue for gas exchange?

thoracic aorta and intercostal arteries

trachea, bronchi

The bronchial circulation arises from the _________ and ________ and supplies the ______ and __________ to the level of the bronchioles

False: PULMONARY circulation is the largest capillary bed in the body

True/false: the bronchial circulation is the largest capillary bed in the body

filter

due to the small diameter of the capillaries, the pulmonary circulation serves as a sort of blood __________

deliver blood for gas exchange

filter small thrombi

trapping of leukocytes

What are three functions of the pulmonary circulation (3)

pulmonary capillaries

___________________: tiny vessels surrounding alveoli where gas exchange occurs

shortness of breath, heart strain

pulmonary hypertension: High blood pressure in the pulmonary arteries, leading to _______ and ________

blockage

pulmonary embolism: a _______ in the pulmonary arteries, often by a blood clot

pressure, congestion

heart failure can cause increased _______ in the pulmonary system, leading to ________

pleura

_______: Covers the lungs, thoracic structures and thoracic wall.

fluid, blood or lymphatic supply

The pleural spaces contain small amounts of _________ but no direct _______ or ______________

(kinda a stretch on the wording I know. but whatever)

mediastinum

___________: Anatomic space bordered by the sternum, pleural surfaces of the lungs, diaphragm and vasculature

thoracic cavity

in some species, the mediastinum completely divides what?

guttural pouch

________: A ventral diverticulum of the Eustachian tube.

cooling of blood in the internal carotid, pressure equalization

Allegedly, the guttural pouch is essential for _______________ in the __________ and __________________

right: cranial, middle, caudal, accessory;

left: cranial and caudal

What are the lung lobes in a dog/cat/cow?

right:______________________

left:________________________

right: cranial, middle, accessory;

left: cranial and caudal

What are the lung lobes in a horse?

right:______________________

left:________________________

pulmonary lobule

__________________: Clusters of 3-5 terminal bronchioles with their acini form this

collateral ventilation

________: "the ventilation of alveolar structures through passages or channels that bypass the normal airways"

For our purposes, this would mean that if one lobule of the lung is infected with something, it could spread to other lobules

true

true/false: cattle and pigs have extensive lobulation due to abundant connective tissue... which means that if one lung lobule is infected with something, it's a lot less likely for the infection to spread to other lobules

olfactory neuroepithelium (smell receptors)

stratified squamous (in the nose to be tough)

ciliated pseudostratified respiratory epithelium (push secretions)

The entire respiratory tract is covered by epithelium... what are the three kinds?

epithelium

(olfactory neuropithelim, stratified squamous, ciliated pseudostratified respiratory epithelium)

submucosal gland

cartilage

smooth muscle

What are the 4 cells types in the conductive and transitional systems?

________: lines the entire tract

_______: secretes layer of mucociliary escalator

_______: for support

_____: support and pliability

olfactory neuroepithelium

___________: present in portions of the nasal cavity that contain specialized cells that bind to odorants to enable sense of smell

odors

chemical to electrical

relay

olfactory neuroepithelum functions to:

◉ detect ________

◉sensory transduction converting the _________ signals into ________

◉ neural r____

limited

so if damaged, lose smell receptors

olfactory neuroepithelial cells have a ______regeneration capacity. what does this mean?

cytochrome p450

some metabolites are more toxic than the full inhalant

the olfactory neuroepithelium, contains ______ which aids to metabolize inhalants... breakdown the chemicals we breathe in (to decode) why might this be a bad thing?

stratified squamous epithelium

what type of epithelium covers the nares?

injury

stratified squamous epithelium is resistant to ___________

ciliated epithelial cells

what type of epithelium covers 95% of the conductive system and is a vital part of the mucociliary escalator?

metaplasia squamous epithelium

cilia

mucociliary escalator

ocassionally ciliated epithelial cells can be damaged so extensively that the cells die and are replaced with ___________ _________ _______. this replacement and occurrence results in loss of ______, and decreased function of the __________ ________.

squamous epithelium, chronic irritation

metaplasia of the respiratory epithelium to ____________ can occur in instances of ___________

cilia, mucociliary escalator

in chronic irritation, when the epithelium becomes squamous, this results in a loss of ________ and decreased function of the __________

club cells (non-ciliated)

________: considered the stem cells of the upper and lower respiratory tract. these cells secrete a thin protein rich fluid and are metabolically active

bronchioles

stem cell

metabolically active

to be a bottom mucus layer bc cilia need a slippery surface to work properly

club cells are doind in the small _______ where the airways get thin and delicate. they are considered to be a ________ _____ of the upper and lower respiratory tract since they are ________ _____

club cells secrete a sol layer- bottom mucus layer, for why?

metabolically

oxidazes (CYp450)

* gotta be aware of the breakdowns though

Club cells have efficiency for being _________active, containing ____________ to detoxifiy compounds

1) alevolar epithelium

2) macrophages

3) endothelium

4) fibroblasts

the cell types in the gas exchange system are: (4)

type I and type II pneumocytes

alveolar epithelium, a cell type in the gas exchange system, contains what two types of cells primarily?