Respiratory Physiology: Ventilation & Resp Physiology II- pulmonary circulation (Exam 4) Flashcards
What are the 5 functions of the respiratory system?
- Exchange of gases between atmosphere and blood
- Regulation of pH
- Protection of inhaled pathogens and irritants
- Vocalization
- Route for water and heat loss
Exchange of gases between atmosphere and blood:
external respiration
Moves air in and out of lungs:
ventilation
Gases diffuse between:
alveoli and blood
What systems work together to regulate blood pH?
renal and respiratory system
Pleural membrane that attaches to the surface of the lung:
visceral pleura
Pleural membrane that covers the surface of the chest wall, diaphragm, and mediastinum
Parietal pleura
pleural membrane that contains a thin layer of pleural fluid (serous fluid) under negative pressure:
pleural space
The pressure in the pleural space is referred to as:
intrapleural pressure (Pip)
It is critical that intrapleural pressure remains at a:
subatmospheric pressure
Intrapleural pressure remains at a subatmospheric pressure which ensures:
the lungs are held to the chest wall and will move with the chest wall during inspiration and expiration
What happens to the value of intrapleural pressure during inspiration and expiration?
value changes
excess fluid in the pleural space:
pleural effusion
Effects of a pleural effusion:
makes lung expansion difficult so the person will breath shallow and fast
The extra fluid of a pleural effusion can be:
blood or lymph or etc
Each lung is located:
in its own pleural cavity
Describe the pressure in the lung tissue compared to the pleural space:
pressure is always greater in the lung tissue
The greater pressure of the lung tissue compared to the pleural space allows for:
holds the lung open, prevents collapse
During contraction what happens to the diaphragm?
flattens which changes volume of thoracic cavity
Lung expansion is necessary for:
inhalation
Describe the breathing pattern of an individual with a pleural effusion:
breathing= shallow and fast
the right lung has ___ lobes; the left lung has ____ lobes
right =3
left =2
Each lung has zones that differ in:
- amount of air (ventilation)
- amount of blood received (perfusion)
Ventilation is represented by:
Perfusion is represented by:
V; Q
The perfect scenario for a lung is a VQ ratio=
1
A VQ ratio of 1 would mean:
ventilation equal to perfusion
The lung is divided into ____ zones
3
All lung zones differ in the amount of:
airflow and bloodflow
The most narrow portion of an organ:
The broadest surface of an organ:
apex; base
The base of the lung is located ____ while the apex is located ____.
inferiorly; superiorly
Zone 1 is located at the ____; Zone 3 is located at the _____.
apex; base
There is a greater ventilation (V) of alveoli and blood flow (Q) into capillaries in zone ____ compared to other zones
zone 3
Which zone is the best region for gas exchange?
zone 3
T/F: Normally most of the lungs are zones 2 and 3
True: in a healthy individual zone 1 is likely nonexistant
The respiratory system is divided into what two functional zones?
- conducting zone
- respiratory zone
When we divide the respiratory system into the conducting zone and respiratory zone we are doing this based on:
functional distinction
The trachea, bronchi, bronchioles, and terminal bronchioles are all part of the:
conducting zone
The respiratory bronchioles, alveolar ducts, and alveolar sacs are all part of the:
respiratory zone
Where does the conducting zone end? Where does the respiratory zone begin?
terminal bronchioles; respiratory bronchioles
As you move down the respiratory system from the conducting zone to the respiratory zone, the diameter of tubes _____ and the number of tubes _____.
decreases; increases
There is a large ____ as you move deeper into the conducting zone and exchange surfaces
increase in surface area
What is the significance of the increase in surface area as you move deeper into the conducting zone and exchange surfaces?
Increased ability to do gas exchange
As you move down the respiratory system from the conducting zone to the respiratory zone, airways have a _____ in cartilage and a ______ in smooth muscle as you move along the airways
decrease; increase
Benefit of cartilage within the respiratory system=
keeps airway from collapsing
What smooth muscle in the terminal bronchioles and respiratory bronchioles allow for?
bronchoconstriction and bronchodilation
Bronchoconstriction and bronchodilation allow us to match:
ventilation to areas of good blood flow
T/F: The conducting zone has cartilage. The conducting zone has smooth muscle.
both statements true
What 3 functions occur in the conducting zone?
air is warmed, air is humidified, air is filtered
In the conducting zone, describe the functions of cartilage and smooth muscle:
cartilage prevents collapse; smooth muscle alters resistance to airflow
Smooth muscles alters _____ to airflow in the conducting zone
resistance
What are some factors that allow smooth muscle to alter the resistance to airflow in the conducting zone?
- beta 2 receptors
- muscarinic receptors
- allergen activation
The ____ zone has a greater surface area to optimize the surface area available for gas exchange
respiratory zone
Equation for velocity:
Velocity= flow / cross-sectional area
Total cross-sectional area greatly increases in the respiratory zone, so velocity of airflow in this zone is:
low
What is the significance of the low velocity of airflow in the respiratory zone?
The slower air moves (velocity), the more time we have for gas exchange
Describe the total cross-sectional area of the conducting zone compared to the respiratory zone:
The total cross sectional area of the respiratory zone is much greater due to numerous bronchioles compared to ONE trachea
Describe the basement membrane of the endothelium and of the alveolar epithelium:
fused
Describe where the fusion of the basement membrane occurs in the respiratory zone:
between capillary endothelium and alveolar epithelium
What is the purpose of the fusion between the basement membrane of the endothelium and of the alveolar epithelium:
faster diffusion
The respiratory membrane is made of:
2 squamous epithelial cells back to back
Types of cells in the alveoli: (3)
- Type 1 cells
- Type 2 alveolar cells
- macorphages
The type 1 cells in the alveoli are:
simple squamous epithelial cells
The type 1 cells in the aveoli make up:
the wall of the alveoli
What occurs through the type 1 cells making up the wall of the alveoli:
gas exchange
Describe the function of the type 2 alveolar cells in the alveoli:
produce surfactant
What type of function is provided by the macrophages in the alveoli:
immune fxn- phagocytosis
The typical transit time at rest for an erythrocyte through an alveolar capillary is:
0.75 seconds
How much time is available for gas exchange to occur for a RBC through the alveolar capillary?
0.75 seconds
Gas exchange is usually complete in:
0.25 seconds
Diffusion equilibrium occurs when PAO2 and PaO2= ______ and when PACO2 and PaCO2 = _____
PAO2 & PaO2= 100
PACO2 & PaCO2= 40
Since the partial pressure of oxygen in the alveoli is higher than it is in the blood ( 100 vs 40) what will occur?
Oxygen will move down its gradient from the alveoli and into the blood
Since the partial pressure of Co2 is higher in the blood than in the alveoli (45 vs 40), what will occur?
Co2 will move down its concentration gradient from the blood into the alveoli
When talking about partial pressures,
A=
a=
A= alveolar
a= blood
Moving air in and out of the lungs:
ventilation
Respiratory muscles are ____ muscles
skeletal muscles
In respiratory muscles, neurons in the medulla and pons control their:
alpha motor neurons
List the key inspiratory muscles:
- diaphragm
- external intercostals
Contraction of the inspiratory muscles ____ the size of the thorax and lungs resulting in:
increases; decrease in alveolar pressure
When are expiratory muscles used?
forced expiration ONLY
List the key expiratory muscles:
internal intercostals, and abdominal muscles
Contraction of the expiratory muscles ____ the size of the thorax and lungs resulting in:
decreases; increase in alveolar pressure
If lungs appear shrunken on an x-ray, what is occuring?
expiration
If the lungs appear inflated on an x-ray, what is occuring?
inspiration
If the chest wall and lungs are expanded what process is occuring?
inspiration
During inspiration the expansion os the ribs has what effect on the sternum?
moves sternum upward and outward
If the chest cavity and lungs are contracted, what process is occuring?
expiration
During expiration what happens to the ribs and sternum?
ribs and sternum depress
The sternocleidomastoid and scalenes are muscles involved in:
inspiration
The external oblique, internal oblique, transversus abdominus and rectus abdominis are muscles involved in:
Active expiration
Active expiration occurs if you want to breathe out more than:
500ml of air
Does active expiration occur if you are calmly breathing in class?
NO
The ____ is the primary inspiratory muscle:
diaphragm
The diaphragm arches over the _____ and moves ____ like a piston when it contracts, which ____ the size of the thoracic cavity and _____ the pressure in the thorax/lungs
liver; down; increases; reduces
During active expiration, the _____ Muscle push abdominal contents against the diaphragm (compressing the lungs) and the ____ depress the ribs
abdominal muscles; internal intercostals
Pressure-Volume Relationships:
- Air is a mixture of:
- Gases have different:
- Air moves from ___ to ___.
- gases
- pressures
- high pressure to low pressure
According to Boyle’s Law, in a sealed container, pressure times volume equals:
a constant
According to Boyle’s Law, if pressure increases, volume will:
decrease
According to Boyle’s law, what variable will change first? What variable will change first with respiration?
pressure; volume
How does the respiratory system get a change in volume?
contraction of muscles
For air to ENTER the lungs, the pressure in the alveoli (Palv) must be _____ than atmospheric pressure (Patm)
lower
If volume is increasing and pressure is decreasing, this is describing aspect of respiration?
inspiration
For air to LEAVE the lungs, the pressure in the alveoli (Palv) must be ____ than the atmospheric pressure?
higher
A decrease in volume and and increase in pressure is describing what aspect of respiration?
Expiration
Humans are ____ pressure breather; what does this mean?
negative, for us to breathe in we have to suck air into the lungs DOWN a pressure gradient
A preemie baby is put on positive pressure ventilation, what does this mean?
Air is being pushed into the lungs rather than pulled into it
What is the purpose of contracting the respiratory muscles during inspiration?
To get a volume change which will allow for the pressure to change in the opposite direction
What allows for the gradient for airflow?
Increase in alveolar pressure
The lungs and chest wall are:
Elastic
The chest wall and lungs both wish to:
recoil apart
What is the natural direction of recoil for the chest wall?
outward
What is the natural direction of record for the lung?
inward
When the chest wall recoils outward this moves it:
away from the lungs
The inward recoil of the lungs is due to:
alveoli
The elastic recoil of the lungs favors:
a decrease in lung volume or compression
The elastic recoil of he lungs favors a decrease in lung volume or compression which is ultimately favoring:
expiration
The elastic recoil of the chest wall favors:
an increase in lung volume or expansion
The elastic recoil of the chest wall favors an increase in lung volume or expansion which ultimately is favoring:
inspiration
The ____ overcomes the recoil between the lungs and chest wall
intrapleural fluid
The intrapleural fluid overcomes the recoil of the lungs and chest wall, keeping the two:
attached together so when the chest moves, the lungs move with it
Recoilability=
Stretchability=
elasticity
compliancy
Why do we consider the intrapleural pressure to be -5 when in reality it is 755mmHg?
Because we set atmospheric pressure which is 760mmHg equal to 0 and the intrapleural pressure is 5 less than that
A calculated value describing the pressure across the lung wall:
Transpulmonary pressure/ transmural pressure
How can transpulmonary pressure be calculated?
PTP= PALV - PIP
(Pressure of alveolus - intrapleural pressure)
An increase in transpulmonary pressure (PTP) is needed for:
Inspiration
A decrease in transpulmonary pressure (PTP) is needed for:
expiration
The bigger the value of PTP, the bigger the ____ is.
volume change
What value must always be positive in order to hold the lung open?
transpulomary pressure (PTP)
It PIP=PATM, then PTP = ____.
Describe this situation
PTP= 0
There is no longer a force to keep the lungs open (pneumothorax)
The lungs want to naturally recoil inward and ____ is what prevents this
Transpulmonary pressure (PTP)
Why does one collapse lung not cause the other lung to collapse?
Due to each lung being in their own cavity
When beginning inspiration, describe the relationship between Patm and Palv:
Patm= Palv
During inspiration, the inspiratory muscles ____ and causing the volume of the thorax (and lungs) to ____.
contract; increase
During inspiration, the increase in volume of the lungs causes what to happen to the PIP?
decrease in PIP
What is the starting value at rest for PIP? What happens with the initial change in volume?
-5; it goes to -7.5
During inspiration, the increase in volume of the lungs that causes a decrease in PIP, causes what to happen to PTP? Explain why:
Increase in PTP; because PTP= Palv- Pip
where we are getting these values:
Palv = 0 at rest
PIP started at -5. and with the initial change in volume decreased to -7.5 which is why we get an increase in PTP (because we are subtracting a larger negative number)
During inspiration, after PTP has increase, this causes what to happen with Palv?
Palv decreases to -1mmg (from 0 where it started at rest)
When Palv<Patm, air:
flows into the lungs
When Palv<Patm, air flows into the lungs:
a: as air enters the lungs, Palv:
b: Air flow continues until:
a: Palv begins to increase again
b: Palv = Patm
During inspiration, when Palv is less than Patm air flows down its concentration gradient into the lungs. What eventually will happen as air flows in?
Palv= Patm so no more air will flow into the lungs because no difference in pressure = no difference in flow
During resting breathing, what amount of air is moved into the lungs? What is this considered?
500ml; tidal volume
Why is expiration considered a passive process?
because we just have to rely out inspiratory muscles
Expiration begins after inspiration when:
Patm= Palv
Relaxed breathing is referred to as:
eupnea
In expiration, the thorax (and thus the lungs) ____ in volume
decrease
In expiration, the lung volume decrease because the decrease in thorax volume causes a ____ in PIP
increase
In expiration, an increase in PIP causes PTP to:
decrease
In expiration, an increase in PIP causes PTP to:
decrease
In expiration, because volume decrease, lung pressure (Palv):
increases (to +1mmHg)
During expiration, as soon as Palv> Patm, air flows:
down pressure gradient and out of the lungs
What happens to Palv as air is leaving the lungs:
Palv decreases
During expiration, when Palv=Patm:
airflow stops
Compliance =
Change in volume / change in pressure
if the lung stretches easily it has a ____ compliance
high
If the lung is difficult to stretch it has a ___ compliance
low
describe the compliance of the alveoli in the base o the lung; what does this allow for?
the alveoli in the base of the lungs are more compliant and undergo greater expansion during inspiration
The opposite of compliance is elasticity which describes the lungs ability:
to return to its normal, resting position
Easy stretch describes:
Easy recoil describes:
high compliance
high elasticity
Lungs with a lower compliance require _____ to _____.
larger transpulmonary pressure to increase volume
Disease characterized by the destruction of elastic fibers resulting in an increased compliance
Obstructive lung disease
An example of an obstructive lung disease:
emphysema
describe the pattern of breathing for an individual effected by an obstructive lung disease:
deep slow breaths
Why might someone with obstructive lung disease take slow deep breaths?
to reduce the work of breathing
A disease characterized by decreased compliance of the lungs:
restrictive lung disease
What is an example of a restrictive lung disease?
pulmonary fibrosis
describe the breathing pattern of an individual effected by a restrictive lung disease:
shallow and fast breaths
Why might someone with a restrictive lung disease take shallow, fast breaths?
to reduce the work of breathing
accounts for 2/3s of pulmonary elasticity:
surface tension
forces that occur at any gas-liquid interface due to cohesive forces between liquid molecules
surface tension
Surface tension describes the force that occurs at any ____ interface due to the ___ forces between ___ molecules
gas-liquid; cohesive; liquid
The fluid covering of alveoli exerts a constant force favoring:
contraction
The fluid covering of alveoli exerts a constant force favoring attraction which means:
collapse of alveoli
Describes the relationship between surface tension and radius if an alveolus:
The Law of LaPlace
Equation for The Law of LaPlace:
Collapsing pressure= 2(surface tension)/ radius of alveolus
If two alveoli are connected and the surface tension of each is equal, the pressure in the smaller alveolus is:
greater
If two alveoli are connected and the surface tension of each is equal, the pressure in the smaller alveolus is greater. Because of this:
air will flow into the larger alveolus
If two alveoli are connected and the surface tension of each is equal, the pressure in the smaller alveolus is greater. Because of this, air will flow into the larger alveolus . Is this ideal?
No
If two alveoli are connected and the surface tension of each is equal, the pressure in the smaller alveolus is greater. Because of this, air will flow into the larger alveolus. The respiratory system compensates for this by:
altering surface tension via surfactant
______ reduces surface tension and equalizes pressure between alveoli of different sizes (compensates for radius differences)
surfactant
surfactant reduces surface tension and ______ between alveoli of different sizes
equalizes pressure
Pulmonary surfactant is secreted by:
Type II alveolar cells.
Pulmonary surfactant _____ surface tension, (thus ______) and _____ compliance
decreases ; elasticity; increases
You really need surfactant for breathing in to be easier because every tie you breathe in , you’re fighting against:
the elastic nature of the lungs
Surfactant is primarily made up of _______.
phospholipids
Surfactant spreads over the fluid lining of the alveolar surface to:
disrupt surface tension forces
What is surfactants effect on hydrogen bonding?
decreases
Some components of surfactant are components of:
innate immunity
Surfactant is particularly important for reducing surface tension in _____ alveoli
small
Surfactant decreases the work of:
inspiration
Surfactant production is increased with:
hyperinflation of the lungs (such as sighing and yawning), exercise, and Beta-adrenergic agonists
Multiple pathologies are associated with decreases in surfactant production such as:
Infant Respiratory Distress syndrome, Acute Respiratory distress syndrome (ARDS), and chronic smoking
Explain why beta receptors function to increase surfactant production:
Beta receptors function in fight or flight response, which requires more oxygen an therefore more breathing (so it makes sense we would want to make breathing easier this way)
equation for airflow:
airflow= (Patm-Palv) / Resistance
In the respiratory system, how might we physiologically change the resistance in airways?
by changing the radius of the airways
List the determinants of resistance in the respiratory system: (3)
- radius of bronchi/bronchioles
- viscosity of substance
- length of tube
How might we alter the radius of bronchi/bronchioles?
a: bronchodilation
b: bronchoconstriction
c: mucus accumulation
- epinephrine on beta-2 receptors
- decreased oxygen
- increased CO2
These would all have what affects on there radius of airways?
bronchodilation
- acetylcholine on M3 receptors
- increased oxygen
- decreased CO2
- histamine
bronchoconstriction
increasing resistance and decreased flow in bronchi/bronchioles =
bronchoconstriction
The airways with the smallest radius (r) have the highest ____ resistance; but the _____ resistance (R) of that generation is the smallest.
highest individual resistance; total
Describe the effects each of the following have on bronchi/bronchiole radius:
- SNS
- PNS
- SNS- bronchodilation
- PNS- bronchoconstriction
Pathologies that increase airway resistance:
Obstructive diseases
Asthma, Emphysema, and Bronchitis are all examples of:
Obstructive diseases
If resistance increases, what must happen to the difference in pressure (Patm-Palv) to maintain normal airflow? How does this effect work of the lung?
We need to make the change in pressure greater and do this by recruiting more muscles, causing more work for the lung
(flow = change in pressure / radius)
Surface tension accounts for 2/3 of pulmonary elasticity and the other 1/3 is due to:
elastic fibers in lung tissue
What is the average values for a pulmonary function test for a 70kg man (women 20-25% less)?
- Inspiratory reserve volume
- Tidal volume
- Expiratory reserve volume
- Residual volume
- IRV= 3000 ml
- TV= 500 ml
- ERV= 1100 ml
- RV= 1200 ml
Label the following image:
A: IRV
B: TV
C: ERV
D: RV
The air that comes in as a result of taking a deeper breath (more so than a regular breath)
Inspiratory reserve volume
The upward portion of a TV wave is a result of ___ while the downward portion of a TV wave is a result of ____.
inspiration, expiration
The volume of air that you can NEVER get out of your lungs:
Residual volume (RV)
Forcing out more air (past tidal volume)
expiratory reserve volume
In a healthy individual, there is around _____ of anatomic dead space per ____ of ideal body weight.
1ml; pound
The volume of air in the condo tin zone:
anatomic deadspace
If you take in 500 ml of air, around ____ will stay in the conducting zone and ____ will go to the respiratory zone
150ml; 350ml
Why is air that remains in the conducting zone considered “anatomic dead space”
because this air is NOT available for gas exchange
Equation for physiological dead space:
Physiologic dead space = anatomic DS + alveolar DS
Everyone has _____ dead space; however healthy individuals do NOT have ____ dead
anatomic; alveolar
The parts of the lung where the amount of air and blood do not match (VQ mismatch)
alveolar deadspace
Give an example of someone that might have a lot of alveolar deadspace:
someone wit low cardiac output
Lung capacities is a combination of:
Volumes
Total lung capacity is considered a _____ value for a given individual
fixed
Which is a better indicator of gas exchange:
minute/pulmonary/total ventilation or alveolar ventilation and why?
Alveolar ventilation because this tells us how much air is going to get to the respiratory zone
Total ventilation may also be called?
minute ventilation or pulmonary ventilation
Equation for minute/pulmonary/total ventilation:
Tidal volume (ml/breath) x Respiration rate (breaths /min)
Equation for alveolar ventilation:
(Tidal volume - Dead space volume) x respiration rate
If you take in a 2000 ml breath, what will the dead space volume be? If you take in a 200 ml breath, what will the headspace volume be?
150 ml regardless of the size of breath
In order to get more air into the respiratory zone for gas exchange, which is better: deeper breath or faster breath?
Deeper breath
Forced vital capacity and forced expiratory volume are both measurements that reflect airflow within:
large airways
What measurements of expiratory flow are used to test for increased airway resistance?
- forced vital capacity (FVC)
- forced expiration volume 1
The volume of air forcibly expired after maximal inhalation:
Forced vital capacity (FVC)
Fraction of FVC expired during the first second:
Forced expiration volume 1 (FEV1)
Explain how we would measure the forced expiration volume 1:
Patient takes deepest breath possible, holds it for a second, and then they breathe out as fast and hard as they can
What is the normal volume for FEV1/FVC:
0.8 (80%)
FEV1 rejects flow in:
Large airways
If an individual has an FEV1 less than 80% what is this indicative of? This is a sign of:
obstructive lung disease; increased airway resistance
Normal quiet breathing
eupnea
increase rate or volume of breathing due to higher metabolism
hypernea
Increased rate or volume breathing WITHOUT increased metabolism
Hyperventilation
Decreased alveolar ventilation
hypoventilation
Rapid breathing rate (usually with decreased depth)
tachypnea
Difficulty breathing; air hunger
dyspnea
What type of ventilation may occur with exercise
Hypernea
What type of ventilation may occur with an extreme emotional response
hyperventilation
Describe the effects of metabolism on hyper- and hypoventilation:
Don’t have anything to do with changes in metabolism
Panting would be an example of:
tachypnea
If you are blowing up a balloon, _____ may occur
hyperventilation
Shallow breathing, asthma and restrictive lung disease are examples of what pattern of ventilation?
Hypoventilation
Various parthologies or hard exercise may result in what pattern of ventilation:
dyspnea
Normal quiet breathing takes ~ ____% of total body energy
3-5
The energy requirement of breathing will significantly increase if a patient has a respiratory condition that alters:
compliance/elasticity and or resistance
Patients with various pulmonary conditions may require additional energy to feel adequate ventilation up to:
a 50 fold increase
Obstructive vs. Restrictive Diseases:
occur due to increased airway resistance
obstructive diseases
Obstructive vs. Restrictive Diseases:
occur due to decreased lung compliance
restrictive diseases
Obstructive vs. Restrictive Diseases:
Example: pulmonary fibrosis
restrictive disease
Obstructive vs. Restrictive Diseases:
Examples: asthma, emphysema, bronchitis and cystic fibrosis
Obstructive diseases
Obstructive pulmonary disease primarily impacts:
expiration
Obstructive vs. Restrictive Diseases:
Primarily impacts expiration
obstructive
Obstructive vs. Restrictive Diseases:
Primarily impacts inspiration
restrictive
Individuals with obstructive pulmonary diseases will breathe:
slow and deep
Individuals with restrictive pulmonary diseases will breathe:
fast and shallow
Describe what is a result of the shallow breaths associated with restrictive pulmonary diseases:
decrease in tidal volume
Atopic asthma is a ____ disease
obstructive
Atopic asthma is a ___ mediated _____ reaction
IgE mediated- Type 1 hypersensitivity reaction
An allergen leads to an inflammatory response that causes bronchospasm that obstruct airflow
atopic asthma
In atopic asthma the chronic inflammation can lead to: (3)
- impaired mucocilliary response
- edema
- increased airway responsiveness
Describe what occurs in the early phase response of atopic asthma:
bronchospasm & increased mucus production
Describe what occurs in the late phase response of atopic asthma:
continued bronchospasm and increased mucus product a + increased vascular permeability and edema
What are the quick relief medications used to treat atopic asthma and describe what they do: (2)
- Beta-2 agonists: causes bronchodilation
- anticholinergic agents: bronchodilation
What are the long term medications used to treat atopic asthma and describe what they do: (2)
- inhaled corticosteroids: suppress inflammatory response
- long-acting bronchodilators
A disease that can occur with respiratory infections , exercise, hyperventilation, cold air, inhaled irritants, aspirin and other NSAIDS. An immune system hypersensitivity reaction is NOT involved.
Nonatopic asthma
In atopic asthma what do the mast cells release and what does this cause?
Mast cells release cytokines; contraction of smooth muscle
An autosomal recessive disorder resulting in defective chloride ion transport that results in an abnormally thick mucus that obstructs airways:
Cystic fibrosis
Cystic fibrosis is a ____ disease
obstructive
mutation that causes cystic fibrosis and location of it:
CFTR ion channel mutation on chromosome 7
What are the treatment options for cystic fibrosis?
- antibiotics
- Chest PT (percussion and postural drainage)
- Mucolytic agents
- Pancreatic enzyme replacement
Due to the defective chloride ion channel in the epithelial tissue of the airway, there is defective ____ secretion and excessive ___ & ___ absorption
chloride (Cl-)
Na+ and H20 absorption
Describe the secretions as a result of the defective chloride ion channel (excessive Na+ and H20 absorption) in CF:
abnormally thick and viscid respiratory tract secretions
In CF, the abnormally thick and viscid respiratory tract secretions results in: (2)
- development of a microenvironment that is protective of microbial agents
- defect mucocilliary clearance
In CF, the chronic airway obstruction and bacterial infection results in: (2)
Neutrophil influx; release of elastase and inflammatory mediators
What might develop secondarily to CF:
- chronic bronchitis
- bronchiectasis
- respiratory failure
Emphysema is a ____ disease
obstructive
Emphysema results from :
- destruction of elastic fibers
- enlargement of airspace’s due to destruction of airspace walls
What is the biggest risk factor for emphysema?
smokin ciggies
In emphysema, the destruction of elastic fibers causes:
increased lung compliance
How does smoking lead to emphysema?
- releases reactive oxygen species
- recruited neutrophils to area (which also create reactive oxygen species)
Smoking ciggies can cause tissue damage to the alveolar membrane which:
decreases the surface area available for gas exchange
The reactive oxygen species released as a result of smoking causes inactivation of _____ leading to an increase in _____.
inactivation of antiproteases; increase in neutrophil elastase
In a normal healthy lung, the enzyme ____ functions to inactivate ____ before it can _____.
alpha1-anti-trypsin ; inactivates least before it can destroy elastic fibers
What enzyme is in decreased amounts in lungs affected by emphysema:
alpha-1 antitrypsin
What is the function of alpha-1 antitryspin in the lungs?
Inactivates elastase before it is able to destroy elastic fibers
Disease characterized by increased mucus production and inflammatory reaction (may be acute or chronic):
bronchitis
Any pulmonary problem that limits lung expansion (decreased lung compliance)
restrictive respiratory diseases
Restrictive respiratory diseases make ____ much more difficult
inspiration
In restrictive respiratory diseases, tissue injury leads to ___ and the normal architecture of the lungs is disrupted and is replaced with ___
chronic inflammation; scar tissue/fribrosis
In restrictive respiratory diseases, the the normal lung tissue is replaced with scar tissue/fibrosis, this leads to:
a decrease in lung compliance
In restrictive respiratory diseases, patients breathe fast and shallow and because shallow breaths decrease alveolar ventilation there is:
a decrease in gas exchange
Pulmonary fibrosis (idiopathic, drug induced, or environmental), pneumonia, and pulmonary edema are all examples of:
restrictive respiratory diseases
List the signs and symptoms of a restrictive respiratory disease:
- increased respiration rate
- chronic cough (dry & non-productive)
- Polycythemia due to hypoxia
An increased number of red blood cells due to a decreased partial pressure of oxygen:
polycythemia
It takes a red blood cell about ____ to travel through pulmonary circulation at resting cardiac output; about ____ of this time is spent in pulmonary capillaries; when in reality gas exchange takes only about ____.
4-5 seconds
0.75 seconds
0.25 seconds
List the order of blood flow from start to finish circulating:
- vena cava
- right atrium
- tricuspid valve
- right ventricle
- pulmonary valve
- pulmonary artery
- pulmonary capillaries
- pulmonary vein
- left atrium
- bicuspid valve
- left ventricle
- aortic valve
- aorta
Compared to systemic circulation, pulmonary circulation has: (4)
- lower pressures
- lower resistance
- higher compliance
- lower volume
Pulmonary arteries and arteriole diameters are ___ than systemic arteries and arterioles:
larger
Pulmonary artery and arteriole walls are ___ and ___ which results in ____.
thin & distensible; large compliance
Compared to systemic circulation in which only the veins have a high compliance, in pulmonary circulation what has the high compliance?
arteries, capillaries, AND veins all have high compliance
What is unique about the pulmonary capillaries in pulmonary circulation:
there is a population of capillaries in the lungs that are closed at rest that can be recruited when necessary
Bronchial circulation is part of ____ circulation
systemic
Supplies oxygen and nutrients to the tracheolbronchial tree down to the terminal bronchioles and also pulmonary blood vessels, visceral pleura, nerves, and hilar lymph nodes
bronchial circulation
What supplies the nutrients and oxygen to the conducting zone of the respiratory system?
bronchial circulation
Bronchial flow is about ___% of cardiac output of the left ventricle
2%
Since bronchial flow is about 2% of cardiac output of the left ventricle, this means that the blood in the left atrium has a _____ than the blood in the pulmonary capillaries
a slightly lower O2 concentration
Since bronchial flow is about 2% of cardiac output of the `left ventricle, this means that the blood in the left atrium has a slightly lower O2 concentration (PaO2 = 95) than the blood in the pulmonary capillaries since:
some deoxygenated blood from the bronchial veins mixes with the oxygenated blood in the pulmonary veins
Describe bronchial flow:
blood flows from the LEFT VENTRICLE through the AORTA in the same way oxygenated blood would get to the organs BUT some of the blood is deposited into the BRONCHIAL ARTERY where it will oxygenate the non- alveolar tissue of the LUNGS
The resulting deoxygenated blood will then get mixed into the PULMONARY VEIN’S (oxygenated blood) lowering the oxygen content from 100 —> 95 and then will dump into the LEFT ATRIUM
Structures in the respiratory zone receive oxygen directly by ____ from the ____ and receive nutrients from the ____ in pulmonary circulation.
diffusion from the alveolar air; mixed venous blood
The pulmonary circulation has ___ pressure & ___ resistance
Low pressure and low resistance
Pulse pressure equation:
pulse pressure = systolic pressure - diastolic pressure
Mean arterial pressure equation (2):
MAP = Diastolic pressure + 1/3 pulse pressure
MAP = CO x TPR
Give the averages for MAP of systemic circulation and MAP of pulmonary circulation as well as blood pressure for each:
Systemic circulation: MAP= 93mmHg and BP= 120/80
Pulmonary circulation: MAP= 14mmHg and BP= 25/8
Describe the pressure patterns from the pulmonary artery to the pulmonary capillary to the left atrium:
pulsatile from pulmonary artery to pulmonary capillaries and not pulsatile from pulmonary capillaries to left atrium; pressure decreases a long the way
By the time the blood moves through pulmonary circulation and reaches back to the left heart, the pressure is only about:
5mmHg
List the average MAPs for the following
Pulmonary artery:
Pulmonary capillary:
Left atrium:
pulmonary artery= 14
pulmonary capillary= 7
left atrium= 2-5
The filtration force in the pulmonary capillaries:
pulmonary capillary pressure
Pulmonary blood volume accounts for ~ ___ % of blood volume but is ___.
9%; highly variable
What are three ways in which pulmonary blood volume varies:
- volume increases during inspiration
- lying down increases the blood volume
- disease states (ex. heart failure) can increase blood volume
Describe why pulmonary blood volume increases during inspiration:
Because PIP because more negative (-5 to -7.5 mmHg) and this actually pulls extra blood back into the thoracic cavity (vacuum suction)
describe why lying down increases the pulmonary blood volume?
due to gravity
Describe why disease states like heart failure can increase blood volume?
because blood can get backed up into the lungs
Because pulmonary vessels are far more distensible/compliant, they are able to alter their size and adjust to _____.
changing pulmonary volumes
Cardiac output increases 4-7 times with heavy exercise. What effect does this have on pulmonary artery pressure?
only a small increase
When pulmonary capillaries are recruited, what will opening more capillaries do to the total resistance?
This will result in an increase in surface which decreases resistance
The pulmonary circulation is not as prone to ____ as the systemic circulation
hypertesnion
During exercise, CO (flow) may increase 7 fold but MAP in the pulmonary circulation will only increase 1-2 mmHG. How is that possible?
An increase in blood flow will cause a decrease in PVR
Describe the difference of the MAP equation in systemic circulation vs. pulmonary circulation
MAP= CO x TPR in systemic circulation
MAP= CO x PVR in pulmonary circulation
What is a mechanisms that produces a decrease in PVR with an increase in blood flow (CO)?
- recruitment of pulmonary capillaries
- distension of pulmonary capillaries
Why do we have mechanisms to decrease PVR in times of increased blood flow?
To keep MAP stable
An increase in blood flow = a ____ in PVR
decrease
When PAO2 (alveolar concentration of O2) drops 70% below normal, what occurs:
adjacent blood vessels constrict which will increase the resistance (up to 5x increase in R)
When PAOS (alveolar concentration of O2) is high, what occurs?
Adjacent vessels will dilate (bringing more blood to alveolus)
What is the functional result of constricting and dilating vessels with changes in PAO2?
blood is delivered to alveoli where it will be most effective at gas exchange
What happens through out the pulmonary circulation at a high altitude where PAO2 is reduced?
we will constrict blood vessels all through out the lungs to decrease blood flow because all areas of alveoli are getting reduced airflow
When PAO2 is reduced and we constrict blood vessels through out the lungs to decrease blood flow (in a situation like high altitude), this can lead to:
Pulmonary HTN
What response occurs in systemic circulation when PaO2 levels drop?
In systemic circulation if blood O2 drops (PaO2) to a tissue, this produces the opposite effect resulting in vasodilation (active hyperemia)
What situation is this showing?
perfusion of well ventilated alveoli and maximal gas exchange
What situation is this showing?
Perfusion of a hypoventilated alveolus with no response of vasoconstriction = decrease PaO2
What situation is this showing?
hypoxic pulmonary vasoconstriction (HPV) in response to a decreased PAO2 (which works to reduce blood flow to hypoventilated alveoli)
Compare the effects of systemic capillaries vs. pulmonary capillaries?
Opposite effects; systemic = delivers O2 to tissue and pulmonary = pick up O2 and drop off CO2
What mechanisms occurs to reduce blood flow to hypoventilated alveoli?
hypoxic pulmonary vasoconstriction (HPV)
List the vasodilators for pulmonary arterioles: (7)
- High O2 in alveoli
- Dopamine
- Bradykinin
- Prostacyclin
- Nitric oxide
- Histamine (H2)
- Acetylcholine
List the vasoconstrictors for pulmonary arterioles: (7)
- Low O2 in alveoli
- High CO2 in alveoli
- Norepinephrine
- Angiotensin II
- Endothelin
- Vasopressin
- Thromboxane A2
What is significant about the following vasoactive substances for the pulmonary arterioles?
Vasodilators: high O2 in alveoli
Vasoconstrictor: low O2 in alveoli & high Co2 in alveoli?
Opposite response in pulmonary arterioles than what is produced in systemic arterioles with the same changes in gas concentration
Lung volumes have a ___ effect on pulmonary vascular resistance (PVR)
passive effect
the ___ vessels include pulmonary capillaries, smallest arterioles, and venules
alveolar vessels
The ___ vessels are all the other vessels not including the pulmonary capillaries, smallest arterioles, & venules
extra-alveolar vessels
= the total of alveolar vessels + extra-alveolar vessels resistance
PVR (pulmonary vascular resistance)
When the alveoli expand during inspiration:
1) _____ are compressed/elongated and their resistance increases
2) ____ have decreased resistance
1) alveolar vessels
2) extra-alveolar vessels
Why do the extra-alveolar vessels have a decreased resistance in times of inspiration?
Because when you breathe in, PIP gets more negative and resulting in a pressure difference across the wall, which therefore pulls the vessel open and ultimately decreases resistance
Why do the alveolar vessels have an increased resistance in times of inspiration?
Because alveolar vessels get compressed with inspiration as the alveolus gets bigger, and will passively compress the alveolar vessel; ultimately increasing the resistance
Resistance in the pulmonary circulation is lowest when:
lung volume is equal to FRC (functional residual capacity)
The volume of air in the lungs after normal (TV) expiration:
FRC
At low lung volumes, extra-alveolar volumes resistance ____ which has what effect on total PVR?
increases; increases
At high lung volumes, alveolar vessel resistance ____ which has what effect on total PVR?
increases; increases
Hydrostatic pressure gradients in the lung alter _____ pulmonary blood flow
regional
When in an upright position, there is a ____ difference in pulmonary arterial pressure from the apex to the base of the lung. This is due to ______.
23 mmHg; gravity
Zone 3 of the lung has the highest ____ and thus the highest ___ per alveolus
hydrostatic pressure; blood flow
What zones of the lung does exercise increase blood flow to?
All zones of the lung though the bottom of the lung still receives the most blood flow
Pulmonary capillaries in the zones of the lung experience force from fluids inside _____, and outside the vessel ___.
Inside vessel: Pa= hydrostatic pressure
Outside vessel: PALV= alveolar air pressure
The hydrostatic pressure of blood inside the capillaries (how do we abbreviate this)?
Pa
The hydrostatic pressure of blood inside the capillaries favors ___ and functions to ____
filtration; keep the vessel open
Pa is greater in zone ___ of the lungs compared to zone ____ due to _____.
Zone 3; Zone 1; gravity
The tissue pressure of the lungs is largely based on:
alveolar air pressure (PALV)
The tissue pressure (largely based on alveolar air pressure - PALV) outisde of the capillary opposes ____ and favors ____.
Opposes filtration; favors vessel collapse
Only the capillaries & smallest of the arterioles & venues (alveolar vessels) are altered by:
PA (Pressure-Alveolar)
A pressure that can compress and close the vessel:
PALV
A pressure that can hold the vessel open because it is the pressure inside the vessel:
Pa (sometimes referred to as Pc)
The capillaries at the base of the lungs have a higher ____ meaning it will hold the vessel open more efficiently
hydrostatic pressure
The pulmonary capillaries near the alveoli can become ____ during ____.
compressed during inspiration
What happens to the resistance of the vessel in the alveolus when there is more air in the alveolus and why?
The resistance of the alveolus goes up if the alveolus has more air in it because there is more external pressure from the outside compressing that vessel.
In zone 1: P-arterial (Pa) is _____ than P-Alveolar (PA). This means that the capillaries are ______.
Pa lower than PA
compressed
If P-arterial (Pa) drops or P-Alveolar (PA) increases (positive pressure breathing), a greater portion of the lung is converted to:
zone 1
Compared to zone 1, zone 2 has a higher ____ due to ___.
P-arterial (Pa) due to gravity
Because zone 2 has a higher p-arterial (Pa) due to gravity, this means that P-arterial (Pa) is ____ than P-Alveolar (PA) during _____.
higher; systole
In zone 2, during diastole what occurs with the P-arterial (Pa) and P-alveolar (PA)
During diastole, P-arterial (Pa) will drop lower than (PA).
In zone 2, because of the pressure differences during systole and diastoles, we call this the region of:
intermittent blood flow
In zone 2, during systole (heart contraction) the vessels are _____ and during diastole (heart relaxation) the vessels are _____.
systole- open
diastole- closed
Zone 3 has the highest ____ due to ____.
P-arterial (Pa) due to gravity
Zone 3 is considered the region of:
continuous blood flow
Why is zone 3 considered the region of continuous blood flow?
Because P-arterial is higher than P-Alveolar (PA) during both systole and diastole
When does gas exchange occur in zone ? When does gas exchange occur in zone 2? When does gas exchange occur in zone 3?
Zone 1- never
Zone 2- During systole (Pa> PA) - opposite in diastole
Zone 3- All of the time (Pa> PA) - during both systole and diastole
The majority of healthy lungs have ____ & ____ blood flow:
Zone 2 & Zone 3
The majority of healthy lungs have ____ & ____ blood flow:
Zone 2 & Zone 3
Exercise converts ___ into ____ blood flow
Zone 2 to Zone 3
When in the supine position, the lungs have mostly ____ blood flow because ____.
Zone 2; because gravity is reduced
How might someone with diseased lungs be positioned when they sleep or when they are in your dental chair?
More upright if possible
Index of the match between airflow (alveolar ventilation) and pulmonary blood flow (perfusion)
V/Q match
Normal whole lung V/Q =
0.8
Because the normal whole lung V/Q is 0.8 this means that there is more ____ than ____.
blood flow than airflow
In a normal individual, the ____ of the lung has a higher V/Q than the rest of the lung.
apex
As one moves from Zone 1 to Zone 3, there is a ____ in ventilation than blood flow.
slower increase
Fast, shallow breaths = lower _____
tidal volume
Fast, shallow breaths in an upright position causes V/Q mismatch because:
air flows to upper lobes and blood flows to lower lobes
The V/Q ratio at the apex of the lung is ______, meaning:
greater than 1.0; meaning that overall the apex receives more venilation than blood flow
Ventilation in Zone 1:
- Intrapleural pressure is more _____
- Transmural pressure gradient is ______
- Alveoli are ____ and ____
- Overall ____ ventilation
Perfusion in Zone 1:
1. _____ intravascular pressures
2. ____ recruitment
3. _____ resistance
4. Overall _____ blood flow
- negative
- greater
- larger & less
- less
- lower
- less
- higher
- less
Ventilation in zone 1 compared to zone 3:
Ventilation in zone 1 compared to perfusion in zone 1:
Less ventilation in zone 1 compared to zone 3
Ventilation in zone 1 compared to perfusion is more because V/Q ratio is greater than 1
Ventilation in Zone 3:
- Intrapleural pressure is _____.
- ______ transmural pressure gradient
- Alveoli are ____ and ____
- overall ____ ventilation
Perfusion in Zone 3:
- _____ vascular pressures
- ____ recruitment
- ____ resistance
- Overall, ____ blood flow
- less negative
- less
- smaller and more compliant
- more
- greater
- more
- lower
- more
Ventilation in Zone 3 compared to ventilation in zone 1:
Ventilation in zone 3 compared to perfusion in zone 3:
greater ventilation in zone 3 compared to zone 1
Greater perfusion in zone 3 compared to ventilation in zone 3
Alveoli at the ___ of the lungs receive more ventilation than those in the ____.
base; apex
The pulmonary capillaries at the ____ of the lungs receive more blood flow than those in the _____
base; apex
Describe the intrapleural pressure (PIP) at the apex of the lungs compared to the base?
PIP at apex is more negative and at base is less negative ad these average out to ~-5
Responses to V/Q mismatch are:
negative feedback responses
The respiratory and circulatory systems are working to deliver air and blood to the ____ portions of the respiratory membrane
SAME
If ventilation is limited:
- V/Q is _____
- Thus O2 is ____ & CO2 is ____
- Smooth muscles in the _____ constrict
- low
- low; high
- blood vessel
In times of an airway obstruction, we are not getting proper air into that alveolus, therefore what do we want to occur?
What is this referred to as?
We want the blood vessel that is serving this alveolus to constrict
hypoxic pulmonary vasoconstriction
If perfusion is limited:
- V/Q is ____
- Thus O2 is ___ & CO2 is _____
- Smooth muscles in the ______ constrict
- high
- high; low
- bronchioles
In times of low perfusion, why would we want smooth muscles in the bronchioles to constrict?
We would rather send that air to an alveoli that is perfused with blood
What is an example of a condition that may cause low perfusion?
Pulmonary embolus
Pulmonary Capillary Exchange:
Blood traverse pulmonary capillaries in _______ and _____ must occur during this time frame.
0.3-0.8 seconds; gas exchange
Pulmonary Capillary Exchange:
In addition to gas exchange, ____ also occurs and is dictated by ____.
fluid exchange; starling’s forces
Pulmonary Capillary Exchange:
Fluid filtration (F) is determined by _____ and _____.
hydrostatic fluid forces and capillary and interstitial colloid
What are the hydrostatic pressures?
capillary pressure (Pc) & Interstitial fluid pressure (Pif)
What are the osmotic pressures?
Plasma colloid osmotic pressure (pi-p) & interstitial fluid colloid osmotic pressure (pi-if)
movement of things OUT of the capillary bed:
Filtration
movement of things IN to the capillary bed:
Absorption
Determine whether the following pressures result in filtration or absorption:
- Capillary pressure (Pc)
- Plasma colloid osmotic pressure (pi-p)
- Interstital fluid pressure (Pif) - negative
- Interstitial fluid pressure (Pif)- positive
- Interstitial fluid colloid osmotic pressure (pi-if)
- filtration
- absorption
- filtration
- absorption
- filtration
Filtration pressures = a total of:
29mmHg
Describe what makes the total filtration pressure of 29mmHg:
Capillary pressure (Pc) = 7mmHg
Interstitial fluid pressure (Pif)= -8 (use absolute value)
Interstitial colloid osmotic pressure (pi-if)= 14 mmHg
The value of interstitial fluid pressure (Pif) = -8. The negative tells us:
that this is a filtration pressure
The absorptive pressures = a total of:
28mmHg
What makes up the total absorptive pressure of 28mmHg:
plasma colloid osmotic pressure (pi-p)
Because normal filtration pressures are greater than absorptive forces by +1 mmHg (29-28), there is a slight continual flow of fluid from the:
pulmonary capillaries into the interstitial spaces
Fluid that leaves the capillaries is absorbed by ____ and returned to _____.
lymphatic circulation; circulation
Extra fluid that enters the alveoli will be sucked into the interstitial space due to the ____ and then picked up by lymphatic capillaries to keep the alveoli dry
slight negative pressure
The balance of pulmonary capillary and interstitial hydrostatic and colloid pressures can be disrupted resulting in _____.
Describe this phenomenon
Pulmonary edema- large increase in net capillary filtration
Pulmonary edema can occur with: (3)
- left sided heart failure
- mitral valve stenosis
- damage to pulmonary capillary membranes
