Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Respiratory Exam 1 > Alveolar Ventilation and Perfusion > Flashcards

Alveolar Ventilation and Perfusion Flashcards

1
Q

what is the leading cause of low blood oxygen

A

-V/Q inequality

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

PaO2 level that is hypoxemia

A
  • <80 mmHg
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

the total pressure of a mixture of gasses is the sum of

A
  • the partial pressures exerted by each gas
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is conditioning?

A
  • warming, cleansing, and humidifying inspired air
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is the partial pressure of water vapor

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

what happens when you introduce water vapor into a mixture of dry gases

A
  • dry gas partial pressure falls accordingly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what does the blood deliver to the lungs

A
  • CO2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what do the lungs give to the blood

A
  • O2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is alveolar ventilation

A
  • volume of air reaching alveoli to participate in gas exchange x respiratory rate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

the first 150 mL of air that is inspired is

A
  • expired air from the previous breath
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

amount of CO2 produced by the body’s metabolism per minute compared to the amount of CO2 eliminated by alveolar ventilation - during steady state

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

relationship between alveolar ventilation and PACO2

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

increased PaCO2 will result in at change in pH

A
  • fall in blood pH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

can doubling ventilation double PAO2

A
  • no

- cannot rise higher than PO2 of humidified air (150)

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

regulation of ventilation by the CNS is driven primarily by

A
  • arterial PCO2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

hyperpnea

A
  • increase in rate and depth of alveolar ventilation caused by a rise in metabolism
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

tachypnea

A
  • rapid, shallow breathing to maintain sufficient gas exchange
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

apnea

A
  • cessation of breathing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

hypoapnea

A
  • slow, shallow breathing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

PaCO2 of hyperventilation

A
  • less than 35 mmHg
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

PaCO2 of hypoventilation

A
  • greater than 45 mmHg
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

if the lung is functioning perfectly, what will be the partial pressures of gas in the pulmonary blood versus alveolar gas

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

what does the A-a difference compare

A
  • calculated PAO2 and PaO2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

partial pressure of CO2 in alveolar gas versus that in the arterial blood

A
  • equal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

in a subject standing or sitting upright, where is ventilation greatest

why?

A
  • base of the lung

- gravity pulls lung downward and creates more negative interpleural pressure at the apex that holds alveoli more open

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

at end expiration, which alveoli are held more open

A
  • alveoli at top of lung
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

alveoli at the base

A
  • more compliant

- greater increase in volume for a given increase in pressure.

28
Q

pressure, volume of the pulmonary circulation

A
  • low pressure, high volume
29
Q

what does the low pressure of pulmonary circulation help prevent

A
  • fluid extravasation (pulmonary edema)
30
Q

pulmonary arterioles shape, size

A
  • numerous, short, thin walled
31
Q

auto regulation of pulmonary arterioles

A
  • lack autoregulation
32
Q

compliance of pulmonary arterioles

A
  • high compliance
33
Q

pulmonary capillary compliance to arterial pressure

A
  • high compliance
34
Q

capillaries are also uniquely susceptible to

A
  • alveolar air pressure
35
Q

where are extra-alveolar vessels located

A
  • not adjacent to alveoli
36
Q

extra-alveolar vessels when lung volume increases

A
  • increase in caliber and decrease in resistance
37
Q

extra-alveolar vessels when lung volume decreases

A
  • decrease in caliber and increase in resistance
38
Q

alveolar vessels are located

A
  • adjacent to alveoli
39
Q

alveolar vessels when lung volume increases

A
  • decrease caliber and increase resistance
40
Q

alveolar vessels when lung volume decreases

A
  • increase caliber and decrease resistance
41
Q

negative alveolar pressure during inspiration will do what to alveolar vessels

A
  • dilate and decrease resistance
42
Q

positive alveolar pressure during expiration what do what to alveolar vessels

A
  • collapse alveolar vessels and increase resistance
43
Q

high alveolar pressures at high lung volumes create

A
  • lung zones with high vascular resistance and low blood flow
44
Q

high intravascular pressure will do what to alveolar vessels

A
  • increase caliber of compliant ones

- lower resistance

45
Q

increases arterial or venous pressure leads to what in pulmonary vascular resistance

A
  • a decrease in pulmonary vascular resistance
46
Q

what can increased intravascular pressures also do

A
  • recruit previously non-perfused pulmonary capillaries
47
Q

capillaries because the lung is a very low pressure hemodynamic system

A
  • many capillaries may be minimally perfused
48
Q

many capillaries may be minimally perfusion during

A
  • periods of low activity and quiet breathing
49
Q

perfusion pressure and vascular resistance in upper zones of lung

A
  • low perfusion pressure

- higher vascular resistance

50
Q

capillaries in upper lung respiratory units

A
  • susceptible to collapse under influence of alveolar air pressure
51
Q

perfusion pressure and vascular resistance in lower zones of lung

A
  • higher perfusion pressure

- low resistance

52
Q

vascular resistance in zone 1

why

A
  • high. vasculature is snapped close.

- alveolar pressure higher than pulmonary arterial and pulmonary venous pressure

53
Q

result of collapse of alveolar capillaries and expansion of zone 1

A
  • increase physiologic dead space
54
Q

pressures in zone 3

A
  • pulmonary venous and arterial pressure higher than alveolar pressure
55
Q

lung perfusion is highest where

A
  • zone 3
56
Q

why is there a dip in blood flow at the very bottom of the lung

A
  • extra alveolar vessels are compressed at low lung volumes
57
Q

pressure in zone 2

A
  • alveolar pressure intermediate to arterial and venous pressure
58
Q

arterial pressure in zone 2

A
  • high enough to keep capillary open

- closer to the bottom

59
Q

arterial pressure in zone 2 at you go up up the lung

A
  • decreases as you go up the lung

- artery will collapse and pinch off blood flow

60
Q

blood flow in zone 2 dependent on

A
  • difference between arterial and alveolar pressures
61
Q

V/Q is highest at

A
  • apex
62
Q

V/Q is lowest at

A
  • base
63
Q

alveoli in apex of lung

A
  • low compliance
  • low ventilation
  • low blood flow
  • high PAO2
64
Q

alveoli in base of lung

A
  • high compliance
  • high ventilation
  • high blood flow
  • low PAO2
65
Q

hypoxia (low areas of O2 tension) will have what effect on the vasculature

result

A
  • vasoconstriction

- directs blood away and toward more well ventilated areas to preserve V/Q

66
Q

consequence of hypoxic pulmonary vasoconstriction

A
  • increases pulmonary artery pressure
67
Q

result of long standing pulmonary hypertension

A
  • cor pulmonale (right ventricular hypertrophy)

Respiratory Exam 1 (27 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions