Lecture 2 Pulm physio Flashcards Preview

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Flashcards in Lecture 2 Pulm physio Deck (37):
1

respiration is the series of exchanges that leads to the uptake of ____ by cells and the release of ___ to the lungs.

cellular respiration is the use of ____ in _____

O2, CO2;

O2, ATP synthesis

2

Dalton's law: the total pressure of a mixture of gases is equal to the ____

sum of the individual gas pressures;

ie Patm (760) * % gas in atmosphere = P(gas in atmosphere)

3

fick's law of diffusion:
3 things that are typically constant and affect rate of diffusion:

1 thing that changes and thus determines diffusion rate

diffusion distance, molecule size, temperature;

pressure gradients

4

boyle's law:
the pressure and volume of a gas in a system are ____ related

inversely

5

if diaphragm contracts, thoracic cavity volume ___ and the pressure ____. air thus flows ____

increases, decreases, in (ie inspiration)

6

diaphragm is relaxed: thoracic cavity volume ___ and the pressure ____. air thus flows ____

decreases, increase;

out

7

grahm's law:

for a gas dissolved in a liquid, the rate of diffusion is proportional to its _____ and is inversely proportional to what?

proportional to solubility in liquid;

inversely proportional to square root of molecular mass

8

which is more soluble in water, out of CO2 and O2? Which thus has a greater partial pressure in plasma? Which needs less of a pressure gradient for diffusion?

CO2, CO2, CO2

9

O2 is mostly transported in blood as:
CO2 is transported as:

bound to Hb;
HCO3-

10

the intrapleural pressure is always ____ than the alveolar pressure

lower

11

pulmonary blood vessels ____ when hypoxic.

vasoconstrict

12

Hypoxic vasoconstriction of pulmonary vessels causes blood to be diverted to the "good alveolus". this causes an ____ in O2 saturation/partial pressure

increase

13

when a person is standing, blood flow is ____ at the base (zone 3) and ____ at the apex (Zone 1). ventilation is greatest at the ____ and lowest at the _____

highest, lowest;
base, apex

14

Normal V/Q ratio is ___. At zone 1 (apex), the V/Q ratio is ____ due to a larger decrease in _____. At zone 3 (base), the V/Q ratio is ____ due to a larger increase in _____.

0.8;
increased, perfusion;

decreased, perfusion;

15

At the gas exchange area, there is a ____ pressure gradient for O2 than CO2. Which diffuses faster? Why?

larger; CO2, better solubility in plasma

16

hypoxia is a decrease in ____.
hypoxemia is a decrease in _____.

O2 delivery to tissue;
decreased partial pressure of O2

17

hypoxia causes synthesis of ____ and production of more _____

EPO, RBCs

18

an increase in ACE-BAT causes a ____ shift of the Hb-O2 dissociation curve

right

19

increase in ACE-BAT causing a right shift:
A =
C =
E =
B =
A=
T =

A = acid
C = CO2
E = exercise
B = 2,3 BPG (DPG)
A = altitude
T = Temperature

20

a shift to the right of an Hb-O2 saturation curve corresponds with a _____ in affinity of Hb for O2. this causes an increase in ____ of O2 from arterial blood to peripheral tissues

decrease, unloading

21

2,3-DPG is increased during chronic _____ ( ie at high ____). this ____ the binding affinity of O2 for Hb

hypoxia, altitude;

lowers

22

diffusion capacity ____ during exercise due to :
increase in number of _____ participating in diffusion, _____ of alveoli and capillaries, ____ the diffusion distance;
improved V/Q ratio in the ____ of the lungs due to increased ____ to the area

increases;
capillaries;
dilation;
lowering;

apex, blood flow

23

A-a gradient refers to the difference in what?

Alveolar O2 (PA) - arterial O2 (Pa)

24

normal A-a gradient causes of hypoxemia: (2)

high altitude, hypoventilation

25

Increased A-a gradient causes of hypoxemia: (3)

V/Q mismatch, diffusion limitation, R to L shunt

26

a decrease in cardiac output causes (hypoxia/hypoxemia);

anemia causes (hypoxia/hypoxemia)

hypoxia, hypoxia (CO and CN poisining also causes hypoxia)

27

3 forms that CO2 is transported in the blood

HCO3- (majority), Carboxyaminohemoglobin, Dissolved

28

Haldane effect: increase in the concentration of ____ will displace ____ from Hb

CO2, O2 (and vice versa)

29

Haldane effect:
thus, if too much O2 is given to a patient with COPD, there is an increase in plasma ____ and ____ can occur

CO2;
acidosis

30

what is anatomic dead space? what is physiologic dead space?

normally, how do they relate?

anatomic = volume of air present in conducting airways

physiologic = volume of lung which doesn't participate in gas exchange (ie not perfused)

normally physiologic = anatomic

31

compliance is a measure of ______ and is equal to ____ divided by change in ____. what is the opposite of compliance?

distensibility;
volume, change in pressure;

elastance

32

what is the V/Q ratio in airway obstruction?

what is the V/Q ratio in blood flow obstruction (ie pulmonary embolus)?

O;

infinity

33

The _____ center is located in the lower pons and _____ inspiration

apneustic;
stimulates

34

The ____ center is located in the upper pons and _____ inspiration

pneumotaxic;

inhibits

35

the central chemoreceptors are located in the _____. THey are sensitive to changes in ___ and ____ of CSF

medulla;
pH, CO2

36

The peripheral chemoreceptors are located:
They are sensitive to changes in what?

carotid and aortic bodies;

changes in pH, CO2, and O2

37

the chemoreceptors in general are most responsive to changes in ____

CO2