Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Introduction to Respiratory Care > Gas Exchange > Flashcards

Gas Exchange Flashcards

1
Q

What is Respiration?

A

the process of getting air into the body for tissue utilization and removal of CO2 into the atmosphere

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

What are the 4 stages of gas exchange?

A

Breathing: air in and out of lungs
External Respiration: gas exchange with inspired air and the blood in the lungs
Transport: O2 cells to cells and Co2 away from cells
Internal Respiration: gas exchange with the internal organs

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

What are the gases normally composed in the alveoli?

A

O2, Co2, H2O, and N2

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

What is the alveolar air equation?

A

PAO2 = FiO2 x (PB - 47) - (PACO2 / 0.8)

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

What is the normal for the alveolar air equation?

A

99.73 (round to 100)

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

What is diffusion?

A

moving from high pressure to low pressure

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

what are the barriers of diffusion?

A

A/C membrane has 3
- alveolar epithelium
- interstitial space and structures
- capillary endothelium
RBC membrane (Hb)

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

Fick’s Law

A

greater the surface area, diffusion constant, and pressure gradient, the more diffusion will occur

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

For gas exchange to occur between alveoli and capillaries, a difference in ______ must exists

A

Partial Pressure

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

What is an alveolar shunt?

A

Lack of ventilation with adequate perfusion

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

what is alveolar deadspace?

A

portion of tidal volume that enters into alveoli but NO perfusion

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

What does PAO2 stand for?

A

Partial Pressure of O2 in alveoli

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

What does PaO2 stand for?

A

Partial Pressure of O2 in arterial

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

What is the A-a gradient equation?

A

P(A-a)O2

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

What is the normal PAO2?

A

100 mm Hg

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

What is the normal PaO2

A

80-100 mm Hg

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

Number above _____ is a shunt

A

300 (must use A-a gradient)

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

What are the reasons for differences in A-a gradient?

A
  • Right - to - left shunt
  • regional inequalities in ventilation and perfusion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

If FiO2 is .60 or ___ and PaO2 is 60 mm Hg or ___, then a capillary shunt is present.

A

greater, less

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

Increasing FiO2 of a patient with a capillary shunt will not help, you must ______

A

Add pressure, like PEEP

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

True or False: PaO2 is always less than PAO2

A

True, PAO2 is always greater due to the presence of anatomical shunts

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

Blood flow is about ___ times higher at bases

A

20

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

V/Q Ratio

A

^ PAO2 v PACO2 - ^ V/Q
v PAO2 ^ PACO2 - v V/Q

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

What is the dissolved equation?

A

(0.003 x PaO2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is the combined equation?
(1.34 x Hb x SaO2)
26
What is Hb Saturation?
the measure of the proportion available Hb that is actually occupied
27
What is the normal values for combined O2 (arterial and venous)
aterial: 19.5 venous: 14.7
28
What is the normal values for dissolved O2 (arterial and venous)
arterial: 0.3 venous: 0.1
29
What are the normal values for total O2 content (arterial and venous)
arterial: 19.8 venous 14.8
30
What is the total O2 content equation?
CaO2 = (Hb x 1.34 x SaO2) + (PaO2 x 0.003)
31
What is the arterial - venous O2 content equation?
C(a-v)O2
32
What does the arterial - venous equation do?
directly measures how much O2 is consumed
33
What is the normal for arterial - venous content?
5 vol%
34
Rule of Thumb for QT: if the CVO2 is decreased, cardiac output is _______
decreased
35
What is the ventilation equation?
RR x Tidal Volume (VT) = min. volume
36
What is the cardiac output equation (Fick equation)
QT = VO2 / (CaO2 - CvO2) x 10
37
What is the Oxyhemoglobin Dissociation Curve?
curve describes relationship between available O2 and the amount of O2 carried by hemoglobin
38
What is Affinity?
term used to describe O2s attraction to hemoglobin binding sites
39
What changes with affinity?
- pH - body temperature - CO2 - 2,3 - DPG
40
What are the horizontal and vertical values on a normal oxyhemoglobin dissociation curve?
Horizontal : PaO2 is 60 Vertical: Sao2 is 90
41
Right Shift Curve
Decreased affinity Decreased pH Increased CO2 Increased body temp. Increased 2,3 - DPG
42
Left Shift Curve
Increased affinity Increase pH Decreased CO2 Decreased body temp. Decreased 2,3 - DPG
43
What is P50?
O2 tension at which Hb is 50% saturated (Normal P50=26.7 mm Hg)
44
What is Oxygen Reserve?
25% of O2 available on the Hb is given to tissues (normally) Hb still carrying 75%. If tissues need more O2 in an emergency O2 starts popping off at rapid rate
45
3 Methods of CO2 transport in Blood
- dissolved (8%) - binds to Hb (12%) - travels as bicarbonate ion (80%)
46
What is the Haldone effect?
Hb affinity for CO2 increases as O2 dissociates with Hb
47
What is the Bohr effect?
Hb affinity for O2 decreased as CO2 enters blood
48
What affects CO2 removal?
- Inadequate VE - Increased deadspace - V/Q imbalance
49
What are some abnormalities of gas exchange and transport?
- impaired delivery - QT or perfusion decreases - abnormal cellular function
50
What are 2 things that can lead to hypoxia
Arterial blood content decreases - VQ imbalance - Hb deficiencies Circulatory failure - body attempts to shunt blood to vital organs - low reduction in perfusion
51
What is Physiological O2 consumption?
tissue extract as much O2 that is needed for what is delivered.
52
What is Pathological O2 consumption?
delivery falls or demand increases to critical point of delivery
53
What is hypoxic hypoxia?
decrease in PO2 levels
54
What is anemic hypoxia?
decrease in Hb
55
What is circulatory shock
The body attempts to shunt blood to vital organs but with massive blood loss the body attempt is limited
56
What is histotoxic hypoxia?
inability of cells to take up or use O2
57
What is hypoventilation?
increased VCO2 decreased pH ventilation does NOT meet metabolic needs
58
What is hyperventilation
decreased PaCO2 alveolar ventilation increases, lungs remove CO2 faster than being produced
59
What is hyperpnea?
ventilation increases depth and rate due to increased metabolic rates
60
What is a MI/Stroke
Localized loss of blood flow
61
Blood is acidic
Decrease pH
62
Blood is alkaline
Increase pH
63
QT speed
0.25 - 0.75 seconds
64
Normal Hb range
12 - 15
65
What is the normal PACO2
40 mm hg
66
Total O2 content normal
16 to 20 ml dl

Introduction to Respiratory Care (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions