APEX Respiratory Physiology Flashcards

1
Q

Where does dead space end?

A

Terminal bronchioles
Next is respiratory bronchioles, which is where gas exchange begins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Muscles of expiration

A

“I let the air out of my TIRE”
internal intercostals
Rectus abdominis
external oblique/ internal oblique
Traverse abdominis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Muscles of inspiration

A

Diaphragm
External intercostals
Sternocleidomastoid
Scalene muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Primary determinant of CO2 elimination

A

Alveolar ventilation- more important than MV (Ve) bc it includes dead space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Alveolar ventilation formula

A

Vt-Vd x rr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What increases PaCO2/ETCO2 gradient?

A

Things that increase deadspace
PPV
Hypotension- decreased BP decreases ETCO2
Atropine- bronchodilator

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Normal Vd?

A

33%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Define physiologic Vd

A

anatomical Vd + alveolar Vd

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Anatomical vs alveolar Vd

A

Body part is confined to conducting airways
alveoli has ventilation but no perfusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Things that change dead space

A

I- old age, copd, hotn, atropine, decreased co
D- ETT, LMA, Trach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The base of the lung has more / less what in compared to the apex in the sitting position

A

More blood, more CO2,
Less PO2, Less Vq ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

The most compliant part of the lung

A

Base

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

V/Q= infiniti cause

A

Dead space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Does HPV minimize shunt or dead space?

A

Shunt!
Theres no shunting since theres no blood flow
It could be said that it increases Vd bc the air has to travel further for VQ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

VQ=0 means

A

Shunt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

The tendency of an alveolus to want to collapse is indirectly proportional to ____

A

Surface tension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The tendency of an alveoli collapse is directly proportional to ______

A

Radius

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

VQ ratio in Zone 1, does zone 1 always occur? how does lung combat this zone?

A

infinity / 0
Zero blood flow
Does not occur in normal lung
To combat, bronchioles constrict

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Zone 2 VQ ratio

A

1/1=1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Zone 3 VQ ratio

A

0 / infinity
Although, zone 3 is good, most zone 3 is just “shunt-like” bc the Q is higher than V

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Anatomical shunts

A

Thesbian veins (drain L heart)
Bronchiolar veins (drain bronchial blood)
Pleural veins (drain bronchial blood)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Zone 4 lung

A

Too much fluid, not enough removal by lymph
Fluid overload, pulmonary edema, Mitral stenosis,

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Aa gradient can be altered, meaning?

A

Can be increased
Can not be decreased, just stays “normal”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Hypoxemia define

A

PaO2 <80mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Things that increase Aa gradient

A

VQ mismatch (too much V, COPD, embolism)
Older age
Shunt (Pneomonia, atelectasis, alveoli cant touch blood!)
Diffusion impairment- Same as shunt! (Emphysema, ILD, Fibrosis)

25
Q

Aa gradient formula

A

PAO2-PaO2
Normal range is <15mmHg

26
Q

IRV, ERV, Vt, IC, FRC, RV, TLC

A
27
Q

What cant spirometery measure?

A

RV, FRC, TLC, CC, CV

28
Q

What inreases/ reduces FRC?

A

Age- Old people can sigh long af bc high FRC
Sighs recruit alveoli
COPD traps air in FRC
Prone- thats why we do it
PEEP adds air to FRC
—–
Obesity/ pregnancy- no space left over!
GA, light anesthesia, NMB- decreased muscles
Supine- thats why we only prone under emergency

29
Q

CV, things that increase CV

A

The volume above RV where small airways begin to collapse, a bad thing! want it to be small
COPD
LV failure
Obesity/ pregnancy
Surgery
Extremes of age

30
Q

Closing capacity (CC) formula

A

CV + RV
Absolute volume of gas in lungs when collapse begins

31
Q

How does CC ratio to FRC

A

FRC should be higher
If CC higher, more shunts

32
Q

DO2 definition and formula

A

Delivery of O2
CaO2 x CO x 10

32
Q

CaO2 definition and formula

A

Arterial oxygen content (AOC)
(1.34 x hgb x SaO2) + (PaO2 x 0.003)

33
Q

VO2 meaning and range

A

Consumption of Oxygen
250ml/min

34
Q

Increase vs decrease P50

A

Decrease is actually a L shit- HALDANE HOLDS O2- holding stronger to O2
Haldane is about CO2, not O2
HGB F hypocarbia, carboxyhemoglobin, decreased CO, decreased 2,3 DPG (which is also in banked blood) decreased H ions- alkalosis, low Fio2 (gonna hold because its scarce)

Increase is a R shift- BOHR BYE O2- letting go of O2 easily
Bohr is about O2 not CO2
Acidosis, hypercarbia, increased 2,3 DPG (caused by hypoxia which tells body let go of O2!), hyperthermia, high fio2 (can let it go easily)

35
Q

Glucose ATP ratio

A

1:38
1 glucose converts to 38 ATPs

36
Q

What is the biggest ATP producer? lesser ones?

A

electron transport- 34 ATPs
Krebs- 2
Glycolysis- 2

37
Q

The hamburger shift

A

Pertaining to CO2 production and elimination
main character- Cl-
For every molecule of HCO3 that leaves the RBC, a Cl is transported in

38
Q

Hypercarbia effects on O2 demand
Other effects of Hypercarbia

A

Increases it! too much CO2 in blood
Hypoxemia
Hyperkalemia

39
Q

Salicylates effect on minute ventilation

A

Increase!
“Aspirin makes you breathe!”

39
Q

Pacemaker for breathing

A

Dorsal Respiratory center in the medulla
Although, new evidence says pre-botzinger complex in VRG
Door cell- door opens for breathing

40
Q

CO2 Ventilatory response curve

A

Opposite of Bohr haldane
L shift- prompts breathing
R shift- stops the prompt to breathe

41
Q

Pacemaker for expiration

A

Ventral respiratory center in the medulla

42
Q

What inhibits the respiratory pacemaker?

A

Pneumotaxic center in the upper pons

43
Q

What stimulates the respiratory pacemaker?

A

Apneustic center in the lower pons

44
Q

What does the DRC respond to ?

A

pH of the CSH
PaCO2
Although, stimulated by hypoxemia and hypercarbia, and is depressed by PROFOUND hypoxemia and hypercarbia

45
Q

Can CO2 cross BBB? (CCR)

A

Yes, but H can’t

46
Q

What does the central chemoreceptor respond to?

A

H+, although h cant pass bbb, so when co2 diffuses across, it combines with h2o to form h and hco3

47
Q

Peripheral chemoreceptor location and purpose

A

Carotid arteries, transverse aortic arch
monitor for hypoxemia PaO2<60mmHg (hypoxic ventilatory response)

48
Q

How does the peripheral chemoreceptors respond to hypoxemia

A

Raises RMP, opens CA channels, AP is sent down Herings nerve to CN9 to increase ventilation

49
Q

Things that impair hypoxic ventilatory response

A

Endarectomy cuts the limbs of the nerves
Low anesthetic gases 0.1MAC
Volatile anesthetics

50
Q

What prevents over inflation of the lung (reflex, nerve, etc.?)

A

Hering-Breuer Reflex

51
Q

J receptors

A

Hyperventilate, i cause ventilation o_o (side eye)

52
Q

Agents that causes shunt/ prevent HPV

A

DES prevents HPV
TIVA agents will not increase shunts
Vasodilators like dobutamine, CCB will
Vasoconstrictors will cause fast BF and cause shunt

53
Q

How do the stupid lungs respond to zone 3?

A

HPV to prevent shunt

54
Q

Sepsis effect on P50

A

Right shift, take the O2! although it wont

55
Q

Whats another way to say increase dead space?

A

increase paco2 etco2 gradient

56
Q

Does hemorrhage effect Vd?

A

Yes, increases , adds more pathways in the body

57
Q

What drugs increase shunting?

A

Des, SNP

58
Q

VO2 formula

A

250ml/min
3.5ml/kg/min

59
Q

EMLA cream and oxyhemoglobin curve

A

Shifts to the left
EMLA turns into methemoglobin which is a left shift