Lesson 7: Airways Resistance and Lung Volumes

Question 1

what is resistance highly dependent on?

Answer 1

the diameter/radius of the tube

Question 2

what happens to your alveoli and small bronchioles because of the negative intrapleural pressure when we inhale?

Answer 2

alveoli and small bronchioles get pulled open a little bit when we inhale because of the negative intrapleural pressure

Question 3

what happens if there is too much mucous accumulation in the airways?

Answer 3

it can actually compromise your ability to move air in and out of the lung

Question 4

what are the neurological factors that influences airway resistance?

Answer 4

• parasympathetic (acetylcholine) constricts (lowers radius)
• epinephrine (sympathetic) dilates
• histamine constricts (allergic reactions)

Question 5

what type of muscle is bronchioles wrapped in?

Answer 5

smooth muscle

Question 6

information from the ANS comes from?

Answer 6

the brain

Question 7

what does it mean to say “the small airways are under pretty strict neural tone”

Answer 7

the smooth muscle in the bronchioles can contract or relax

Question 8

when you are running from a bear, you have an adrenal rush. something that happens is your airways will open. why?

Answer 8

because your body is sensing a threat. so it is increasing the airways to allow for you to increase flow to run away from the bear

Question 9

what neurologically leads to dilation of small airway?

Answer 9

epinephrine stimulating adrenal receptors on the small airways leads to dilation

Question 10

what does an epi pen do?

Answer 10

opens up the airways to !!!temporarily!!! reduce the allergic reaction which was causing constriction

Question 11

what does an anti-histamine do in terms of respiration?

Answer 11

helps to mitigate and open up the airways

Question 12

when an airway constricts, resistance increases. does this represent smooth muscle contraction or relaxation?

Answer 12

contraction

Question 13

what are the two types of diseases of the airway?

Answer 13

1. obstructive diseases
2. chronic obstructive pulmonary disease

Question 14

what is “obstructive diseases”?

Answer 14

• the diameter of the airways may be a little bit lower and the resistance might be a little bit higher

Question 15

if you have an increased airway resistance, to generate the same level of flow, you need to have?

Answer 15

a larger pressure generation

Question 16

what type of respiratory disease is asthma?

Answer 16

obstructive

Question 17

what is asthma?

Answer 17

• bronchoconstriction leading to airflow obstruction
• generally a disease of the small airways.
• can be seasonal
• can be based on triggers to certain environmental challenges, whether, exercise, smoke, pollutants

Question 18

the bronchoconstriction in asthma is generally a secondary cause after?

Answer 18

neurological factors such as smooth muscle constriction

Question 19

does individuals with asthma have inflammation of the airways?

Answer 19

yes
- can lead to bronchoconstriction

Question 20

are individuals with asthma hyper or under responsive to triggers?

Answer 20

hyperresponsive to triggers

Question 21

what type of triggers are individuals with asthma hyperresponsive to?

Answer 21

things like exercise, smoke, pollutants

Question 22

why does the airways constrict during an asthma attack?

Answer 22

to try and move that stuff out. by constricting, it is trying to avoid air coming in

Question 23

how is asthma trated?

Answer 23

1) with anti-inflammatory drugs
2) bronchodilators (reversing the bronchoconstriction)

Question 24

what does bronchodilators do?

Answer 24

• relaxes the airways by:
  a) mimic epinephrine (often beta-2 agonists)(inhalers)
  b) inhibit acetylcholine (getting ride of inflammation)

Question 25

why is bronchoconstriction happening in an asthma attack?

Answer 25

in asthma, they have bronchoconstriction because the smooth muscle is hyper reacting. (constricting more than it probably should)

Question 26

what does a beta-2 agonist do?

Answer 26

Binds with a beta-2 receptor and relaxes the smooth muscle which then dilates the airways which will then decrease the airways resistance

Question 27

in someone with asthma, what happens if you can treat the inflammation?

Answer 27

you can reduce the rate of them having an asthma attack and needing the bronchodilators

Question 28

how do we typically treat asthma?

Answer 28

generally by targeting the smooth muscle and relaxing it

Question 29

what does COPD stand for?

Answer 29

chronic obstructive pulmonary disease

Question 30

what is COPD generally due to?

Answer 30

- tobacco smoking / second hand - if you work in a factory with bad air quality - breathing in toxins - there is going to be damage, an inflammatory response, damage to the airways

Question 31

can asthma be developed?

Answer 31

rarely. usually and genetic predisposition

Question 32

what is COPD characterized by?

Answer 32

the development of both emphysema and bronchitis

Question 33

what is emphysema?

Answer 33

a destruction and collapse of the small airways and also the interface with the pulmonary capillaries and the elastic tissue (recoil pressure) (losing the elasticity of the lung)

Question 34

what is chronic bronchitis?

Answer 34

- chronic inflammation of airways - excessive mucous production in smaller airways (more than asthma)

Question 35

because of what is why individuals with COPD have CONSTANT bronchoconstriction/increased airway resistance?

Answer 35

excessive mucous production (physical factor so a puffer cannot fix this) - also depends on severity of emphysema

Question 36

what is the clinical treatment for individuals with COPD?

Answer 36

the same as asthma, but its only partially reversible

Question 37

each diseases of the airway results in?

Answer 37

a) increased airway resistance b) decreased air flow rate

Question 38

what is the purpose of picking up our breathing?

Answer 38

maintain homeostasis

Question 39

because of diseases in the airway, how may someone's life be affected?

Answer 39

- increased work of breathing - compromises gas exchange - impaired oxygenation of blood

Question 40

what is an example of a restrictive disease?

Answer 40

pulmonary fibrosis

Question 41

what is a restrictive lung disease?

Answer 41

- normal airway resistance - minimal airway narrowing - reduced lung capacity (volume of air)

Question 42

why does people with pulmonary fibrosis have a small lung capacity?

Answer 42

because their lungs are so stiff (low compliance), they can't take as big of a breath in (small volume/capacity)

Question 43

when we breath in, how does our diaphragm know to pull down and make space?

Answer 43

- the medulla sends a signal down the phrenic nerve to the diaphragm and it pulls down and opens the space

Question 44

we could have a respiratory issue at what levels?

Answer 44

- the brain - the nervous system - muscle level - so if there is something wrong in any of those, it can lead to restrictive respiratory physiology

Question 45

what are examples of neuromuscular disorders?

Answer 45

- polio - amyotrophic lateral sclerosis (ALS) - muscular dystrophy (tears in the diaphragm)

Question 46

in heart disease, why can you have a restrictive lung disease?

Answer 46

because you have a pressure fluid buildup in the heart, you get hypertrophy and the heart actually displaces the lungs. it pushes on the lungs and you cannot breathe as much you can get lung disease through heart disease

Question 47

how do we measure the capacity/volume of the lung?

Answer 47

we look at the change in air volume that is displaced on inspiration and expiration

Question 48

what device do we use to measure the capacity/volume of the lung?

Answer 48

a spirometer

Question 49

what did the old spirometer that is 70-80 years old consist of?

Answer 49

an air-filled drum floating in a water-filled sealed chamber - drums sitting in water and hoses attach to it. the hoses measure the inspired and expired breath and the air would go into the chamber and push the drum up or down. We would measure the change in the lung volumes

Question 50

how can flow be determined by a spirometer?

Answer 50

only if we track time - this is critical for measuring lung function

Question 51

what helps to classify/characterize obstructive lung conditions?

Answer 51

flow

Question 52

what is tidal volume (Vt)?

Answer 52

the volume of air entering or leaving the lungs during a single breath; average value under resting conditions

Question 53

what is inspiratory reserve volume (IRV)?

Answer 53

the extra volume that can be maximally inspired over and above the typical resting tidal volume

Question 54

what is inspiratory capacity (IC)?

Answer 54

the maximum volume that can be inspired, starting from the end of a normal, quiet expiration (IC = IRV + Vt)

Question 55

what is expiratory reverse volume (ERV)?

Answer 55

the maximum volume that can be actively expired starting from the end of a typical resting tidal volume

Question 56

your TLC (total lung capacity) is a direct index of?

Answer 56

the size of your lung

Question 57

do we always have a residual volume (RV)?

Answer 57

yes, as long as our lung is not collapsed we will always have a little bit of air left

Question 58

about how much of our total lung capacity is residual volume?

Answer 58

about a quarter

Question 59

when we take a big breath in or a big breath out, what capacity/volume is that?

Answer 59

vital capacity - difference of top or your breath to bottom of your breath

Question 60

does our vital capacity and total lung capacity ever change?

Answer 60

they are pretty set. do not really change - will go down as we age however

Question 61

What are some chronic obstructive pulmonary diseases?

Answer 61

Emphysema and chronic bronchitis