Brainscape's Knowledge GenomeTM

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


See full index

RC Test 2 > B4.030 - Pulmonary Embolism Prework 1 > Flashcards

B4.030 - Pulmonary Embolism Prework 1 Flashcards

1
Q

adequate matching of ventilation and blood flow in the lungs in necessary for what

A

efficient gas exchange

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

what does PAO2 and PACO2 refer to

A

pressure of O2 or CO2 in the alveoli

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

what does PaO2 and PaCO2 refer to

A

Pressure of O2 or CO2 in the arteries

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

what is the A-aPO2 in the real lung

A

about 5 mmHg

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

what is the PaCO2-PACO2 in the real lung

A

about equal

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

describe the dots on the graph and what they represent

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

describe the Ppl, Va, Q, and VA/Q in the lung

A

Ppl - lowest at top (most negative), highest at bottom(least negative)

Va - lowest at top, highest at bottom

Q - lowest at top, highest at bottom

VA/Q - lowest at bottom, highest at top

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

describe PACO2, PAO2 levels at the top of the lung and at the bottom as well as VA/Q

A

PACO2 at the top of the lung is lower than at the bottom

PAO2 is higher at the top of the lung than at the bottom

VA/Q is better at the top

VA/Q is lower at the bottom

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

what type of pathology could cause this

A

differences in airway resistance

narrowing of airway A

Chronic bronchitis

increased mucus secretion and swelling of bronchial mucosa

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

what is shown in the picture

A

differences in airways compliance

difference in Ppl is lower in B than in A, so alveolar ventilation is lower in B

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

what type of pathology might cause both of these

A

COPD

Chronic bronchitis and emphysema

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

what can cause an acute blood flow distribution

A

pulmonary embolism

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

what can cause a chronic blood flow distribution

A

alteration fo the pulmonary architecture (pulmonary fibrosis, emphysema)

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

what is the equation to finding the number of dead space units

A

VD/VT = (PaCO2 - PECO2) / PaCO2

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

what is a normal VD/VT ration

A

1/4 - 1/3

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

at what VD/VT level are patients usually ventilated artificially

A

.6

17
Q

what happens to PaO2 in a lung with increased dead space

A

Low PaO2 because perfusion time is lower since youre pushing more blood through the non dead spaces to try and compensate for the increase in dead space

18
Q

what can cause this

A

bronchial occlusion

that area does not undergo gas exchange and keeps venous blood gas pressures

19
Q

what happesn to PO2 when you have a shunt unit

A

you have a large decrease in PaO2

20
Q

why does the artery PaO2 reflect a number lower than the average of the two streams oxygen content?

A

because O2 levels in blood is not linearly related to PO2

it has a sigmoidal shape

O2 content can be averaged to find the resulting O2 content, but NOT PO2

21
Q

why does hyperventilation not help with increasing PAO2 in the case of a dead alveoli

A

becuase in the alveoli that arent affected the O2 level is already high, you arent chanign much because the bood streams are still going to mix resulting in a low PaO2

22
Q

what pathologies can cause venoaterial gas mixture

A

veno arterial shunst

bronchiole obstructions

atelectases

abnormal distribution of ventilation (COPD, chronic interstitial pneumonia)

23
Q

why is there a smaller effect on PaCO2 in the case of alveolar shunt

A
  1. relationship between PCO2 and total blood CO2 content is fairly linear, so its proportional
  2. the difference between arterial and venous CO2 is relatively small compared to the difference in PO2 in veins and arteries
24
Q

why does hyperventilation work for eliminated PaCO2

A

it will lower PCO2 and CO2 content in the lung enough to lower mixed PCO2 arterial PCO2

25
Q

what does a shunt do to PaO2 and PaCO2

A

Large drop in PaO2

Small increase in PaCO2

26
Q

why might you see a patient with high PaCO2 and now PAO2?

A

Because the level of hyperventilation needed to maintain normal PaCO2 is so high not everyone can do it

27
Q

how do you calculate the PAO2-PaO2

A

measure aterial PCO2/PO2

assume PaCO2 = PACO2

PAO2 = PIO2 - (PaCO2 x 1.2)

normally PAO2 is close to measure PaO2

magnitude of difference is indicative of the severity of the shunt

28
Q

what measure will be off in a patient with this pathology

A

VD/VE ratio >.35

29
Q

what measure will be off in a patient with this pathology

A

A-aPO2 > 10 mmHg

RC Test 2 (19 decks)

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