Exam 2 - Lecture 5

Question 1

What is the lower error bar for upright, and what is the upper error bar for supine?

Answer 1

2.6ish -> 2.4ish, thats why positioning may OR may not be statistically significant for every patient.

Question 2

what is higher, ERV or IRV?

Answer 2

IRV

Question 3

What makes up vital capacity?

Answer 3

ERV, IRV, TV

Question 4

What can basic spirometry not cover?

Answer 4

Anything that has RV as a component. So RV, FRC and TLC.

Question 5

What is the indicator gas USUALLY for advanced spirometry? why?

Answer 5

Helium; cheap and inert and theres very low volumes of it in the atmosphere so makes it more accurate to measure.

Do not want to use a gas that is going to undergo any reactions in the lung or be exchanged.

Question 6

How do they measure FRC?

Answer 6

With advanced spirometry, they compare starting concentration with end concentration.

No helium is lost, it’s just diluted out

Question 7

What do you need to use advanced spirometry?

Answer 7

Helium (indicator gas), helium meter, source of oxygen, and CO2 absorbent.

Question 8

What group did he talk about on the periodic table?

Answer 8

noble gases

Question 9

Whats at the top of noble gases?

Answer 9

helium.

Question 10

What other noble gases did he mention you can use as an indicator gas?

Answer 10

Neon, Argon (expensive and rare), Xenon, Radon

Question 11

What did he say about radon gas?

Answer 11

It isnt reactive, but natural radon in the ground is very reactive. Radon gas is the second leading cause of Lung cancer behind smoking, and can be present in basements up north.

Question 12

Emphysema leads to what issues with compliance?

Answer 12

Loss of elastic tissue, becomes much more compliant with low resistance.

Question 13

Emphysema is more or less stretchy?>

Answer 13

He said LESS. It’s confusing, but i believe the lack of stretchiness is related to lack of recoil. it expands just fine, just doesnt recoil well and exhale air.

Question 14

How much transpulmonary pressure do you need to expand with emphysema, starting at RV?

Answer 14

only 10 cmH2O to get to nearly 6L of vital capacity.

Question 15

Restrictive lung diseases such as fibrosis have more or less compliance?

Answer 15

Less, harder to fill.

Question 16

What gets “laid down” in the lungs with fibrosis?

Answer 16

Scar tissue

Question 17

Fibrosis causes what shift on the chart, and what does that mean?

Answer 17

Right shift, more pressure is required and end up with less Vital capacity.

Question 18

Starting at RV, how much pressure is needed to get to what total vital capacity with fibrosis?

Answer 18

35cmH2O is required to only get 3L of vital capacity.

Question 19

What do normal lungs require for pressure and vital capacity starting at RV?

Answer 19

4.5L with a transpulmonary pressure of 30cmH2O

Question 20

At the beginning of inspiration from RV, the P_TP change between 0 and 8cmH2O alters the volume of the lung how?

Answer 20

Doesnt change much, but once it gets above 8, volume increases fast.

Question 21

What would if we hypothetically put all saline into the lungs?

Answer 21

Way more compliant with nearly zero hysteresis.

Question 22

If saline causes there to almost be no hysteresis, that tells us that something about air is affecting the

Answer 22

surface tension.

Question 23

whats the air-water interface

Answer 23

Where air and a very thin layer of water meet eachother.

Question 24

If we have a ton of surface tension, this makes it more or less difficult to get air into lungs?

Answer 24

Much more difficult.

Question 25

When we replace air with saline, the air-water interface is

Answer 25

removed from the lungs

Question 26

Surface tension has a big influence for inhalation of air, especially at

Answer 26

low lung volumes. *This is why there is such low lung compliance between 0-8cmH2O*

Question 27

What is the role of surfactant

Answer 27

Gets in between water molecules and breaks surface tension, making it easier for air to get into lungs.

Question 28

Surfactant is made out of

Answer 28

90% phospholipids, and 10% 4 different surfactant proteins.

Question 29

The 4 surfactant proteins are ______, and which ones are hydrophillic?

Answer 29

A B C and D A and D are hydrophillic, B/C are hydrophobic.

Question 30

Surfactant proteins are a mix of water soluble and insoluble, so they are

Answer 30

amphipathic

Question 31

how do you spell the super long phospholipid and how many syllables is it what % of surfactant does it make up?

Answer 31

Dipalmitoylphosphatidylcholine 10 syllables. 31%

Question 32

Unsaturated phosphatidylcholines make up __% of surfactant?

Answer 32

31%

Question 33

What cells produce surfactant?

Answer 33

Mostly type II and clara/club cells, and a little bit of goblet cells

Question 34

Where are goblet cells located and what do they produce?

Answer 34

mostly mucus, a little surfactant.

Question 35

Where are club/clara cells located?

Answer 35

bottom part of airways/in alveoli

Question 36

what shape are type II cells? why?

Answer 36

Cube shaped so they can fit extra stuff such as golgi apparatus and allat shit

Question 37

Type II cells are between _______

Answer 37

interspersed between type I cells.

Question 38

Surfactant is released by

Answer 38

exocytosis

Question 39

Major gas exchange happens in ________ at what %?

Answer 39

Type I cell, 90-95% of gas exchange.

Question 40

What % of gas exchange occurs by type II cells?

Answer 40

5-10%

Question 41

There are ___ as many type II cells than type I.

Answer 41

2x but type I takes up more space cause theyre long and skinny

Question 42

Whats the crosshatched netting structure called and what does it do?

Answer 42

Tubular myelin Where surfactant hangs out while its inactive, until it gets knocked off by vacuum pressure from air moving in, then it floats up to air-water interface to become active and break surface tension.

Question 43

What is an issue with surfactant and positive pressure ventilation?

Answer 43

The lack of vacuum pressure doesnt knock off as many surfactant off tubular myelin to become active.

Question 44

What breaks down old surfactant that isnt good anymore and what does it do with them?

Answer 44

Alveolar macrophages, turns them into component parts to be reuptaken by surfactant producing cells to recycle and make good again. They also clean up any garbage in lungs.

Question 45

If we arent reproducing more surfactant, surface tension will

Answer 45

increase

Question 46

There needs to be a ______ between rate surfactant falls apart and replaced.

Answer 46

balance *it could also just not be getting knocked off net, same issues*

Question 47

There is _______ where lungs are collapsed.

Answer 47

no surfactant

Question 48

If there is no surfactant where lungs are collapsed, what issue does this cause?

Answer 48

Hard to get it back open and re-recruit, because surfactant isnt breaking up surface tension.

Question 49

What is important for re-opening collapsed lung areas?

Answer 49

Time. Much harder to re-open if its been a day instead of just 30 minutes.

Question 50

What cells release a mediator that irritates the airway, causing airway smooth muscle to tighten?

Answer 50

Mast cells releasing histamine

Question 51

How many alveoli do we have as young adults?

Answer 51

500 million.

Question 52

Can your lungs reproduce alveoli?

Answer 52

Yes, but at a very slow rate (just like the heart)

Question 53

Each alveoli has up to _______ capillaries.

Answer 53

a thousand

Question 54

how many square meters of surface area is available in the lungs for gas exchange in a healthy 20 year old adult, and what is that size compared to?

Answer 54

70 square meters, tennis court.

Question 55

Water surface tension is responsible for ______ of recoil pressure, while elastic tissue of the alveoli are responsible for ___.

Answer 55

2/3rds; 1/3rd

Question 56

Water wants to be ___ other water.

Answer 56

near

Question 57

What disorder has "tons" of springy tissue? what are the issues this causes?

Answer 57

Fibrosis/RLD. Hard to inflate, increased resistance, decreased compliance, easy to exhale. More negative pressures required.

Question 58

There is a ______ in every lung disease ever studied.

Answer 58

Surfactant deficiency

Question 59

Surfactant not only reduces surface tension but also keeps our lungs ___.

Answer 59

dry

Question 60

Surfactant keeps the water layer ____, because this helps with gas exchange.

Answer 60

thin

Question 61

At higher lung volume, air resistance is

Answer 61

low

Question 62

At lower lung volume, air resistance is

Answer 62

high *Just think of it like blowing up a balloon. Hard to start, but once its open, its easy.*

Question 63

Large vessels are held open by ______, but it also holds our _______ ________.

Answer 63

Negative pleural pressure; larger airways open.

Question 64

At the level of the alveolus (small airways), the thing that keeps it open is more related to ______ than the negative intrapleural pressure.

Answer 64

volume

Question 65

What is traction?

Answer 65

Negative pleural pressure holding the larger airways open, allowing for air to come in.