# Transport of Gases Flashcards Preview

## ► Med Misc 44 > Transport of Gases > Flashcards

Flashcards in Transport of Gases Deck (41)
1
Q

Total O2 Carrying capacity of blood:

O2 has a solubility in blood of what numerical value?

A

0.003

2
Q

Calculating the amount of dissolved O2 in blood:

what are the units used when calculating?

A

mL O2/100mLs blood

3
Q

Calculating the amount of dissolved O2 in blood:

what is the equation to calculate?

A
1. 003 x PO2

* *PO2 is PaO2**

4
Q

Calculating the amount of dissolved O2 in blood:

how much O2 is dissolved in arterial blood if PaO2 is 90mmHg

A

0.003 x 90 = 0.27 mL O2/ 100ml blood

5
Q

Calculating the amount of dissolved O2 in blood:

Calculate the increase in dissolved O2 in the arterial blood if PaO2 increases from 50mmHg to 300mmHg

A
1. 003 x 50 = 0.15 mLO2/100ml blood
2. 003 x 300 = 0.90 mLO2 / 100mL blood
3. 90 - 0.15 = 0.75 mLO2/100mL blood increase in dissolved O2
6
Q

Calculating the amount of dissolved O2 in blood:

Who’s law permits the amount of O2 dissolved on O2 tom be calculated?

A

Henry’s Law

7
Q

Calculating the amount of dissolved O2 in blood:

what are 2 things you need to know in order to do the calculation

A

Partial pressure

Solubility

8
Q

Carriage of O2 by the blood Summary:

O2 is carried by the blood in 2 forms…what are they?

A
```Hgb bound (chemical form)
Dissolved (physical form)```
9
Q

Carriage of O2 by the blood Summary:
in a young healthy iundividual normal arterial blood (PaO2=100 mmHg) has _____ mLO2/100mL blood dissolved, and ___ mL O2/ 100mL blood bound to Hgb.

A
1. 3 mLO2/100mL blood

19. 8 mlO2/100mL blood

10
Q

Carriage of O2 by the blood Summary:

the maximum O2 carrying capacity of arterial blood of a healthy person breathing room air is what?

A

20.4 mL O2/ 100mL blood

11
Q

Carriage of O2 by the blood Summary:
the maximum O2 carrying capacity of arterial blood of a healthy person breathing room air is 20.4 mL O2/100 mL blood, ____ mL of O2 is carried by Hb and ____ mL is dissolved

A
1. 1 Hb

0. 3 dissolved

12
Q

Carriage of O2 by the blood Summary:
the ODC is S shaped, the steep portion of the curve occurs when PO2 is less than 60 mmHg. clinical application: Hypoxia is defined as a PaO2

A
13
Q

Carriage of O2 by the blood Summary:
As blood passes through the capillaries of metabolizing tissues, the ODC automatically shifts to the ____ b/c temperature and PCO2 are increased and the pH is decreased, this assist with the unloading of O2

A

right shift

14
Q

Carriage of O2 by the blood Summary:
Blood passing through the Pulmonary capillaries gives up CO2 and pH Increases. The ODC shift to the ____. this facilitates the loading of O2 into Hgb

A

Left shift

15
Q

Carriage of O2 by the blood Summary:
the ___ effect refers to the shift in the position of the ODC in response to changes in PCO2. according the this effect there will always be a rightward shift in the curve in response to an increase in PCO2 and a leftward shift in response to a decrease in PCO2

A

Bohr

16
Q

Carriage of O2 by the blood Summary:

if fetal Hgb (HgF) is present the ODC shifts where?

A

left

17
Q

Carriage of O2 by the blood Summary:

maternal Hgb exhibits a ____ shift

A

right

18
Q

Carriage of O2 by the blood Summary:

if carboxyhemoglobin or methemoglobin is present there is a ___ shift

A

left

19
Q

Carriage of O2 by the blood Summary:

most of the O2 carried in the blood is boud to ___, and only a very small fraction is dissolved

A

Hgb

20
Q

Calculating the amount of O2 bound to Hgb:

what is “normal” Hgb concentration for equations

A

15 g hb/100 mL blood

21
Q

Calculating the amount of O2 bound to Hgb:

to calculate you need to know what 3 things?

A

1) the amount of O2 carried by each gram of fully saturated Hb. (1.34 mL O2 per g Hb)
2) the normal concentration of Hb (15 g per 100 mL blood)
3) the % saturation (90% = 90/100 = 0.9)

22
Q

Calculating the amount of O2 bound to Hgb:

what is the equation

A

O2 Hb = (1.34) x (15) x (0.9)

or O2 Hb = 1.34 x (hb) x % saturated

23
Q

Calculating the amount of O2 bound to Hgb:

calculate the amount of O2 carried by Hb when it’s 90% saturated. (assume normal Hb concentration)

A

1.34 x 15 x 0.9 = 18.1 mL O2/ 100mL blood

24
Q

Calculating the Total amount of O2 carried by the Blood:

what is simple equation

A

O2 bound to Hb + O2 dissolved in blood

25
Q

Calculating the Total amount of O2 carried by the Blood:

Calculate the total amount of O2 carried by the blood when it is 90% saturated (assume normal Hb)

A

1.34 x 15 x 0.9 = 18.1 mL O2/ 100 mL blood
use ODC to find PaO2 90% = 60 mmHg
0.003 x 60 = 0.18 mL O2/ 100 mL/blood

18.1 + 0.18 = 18.28 mL O2 / 100mL blood

26
Q

If SvO2 is 70% how much O2 is dissolved is venous blood

A

SvO2 70% = PvO2 40 mmHg

0.003 x 40 = 0.12 mL O2 / 100ml blood

27
Q

what is another way of writing 100mL blood

A

dL blood

28
Q

Normal values for Venous vs Arterial
Arterial O2 90% = ____ PaO2
Venous O2 70% = ___ PvO2

A

Arterial 60

venous 40

29
Q

CO2 blood dissociation curve:
the ___ effect describes how changes in Partial pressure of O2 (PO2) in the blood influences the blood dissociation curve.

A

haldane effect

30
Q

CO2 blood dissociation curve:

when PO2 in the blood increases, the blood CO2 dissociation curve shifts how?

A

down and to the right

31
Q

CO2 blood dissociation curve:

when the PO2 in the blood decreases, the blood CO2 dissociation curve shifts how

A

up and to the left

32
Q

CO2 blood dissociation curve:

what effect does Opioids have on the blood CO2 dissociation curve? why?

A

shifts it up and to the left b/c opioids decrease PO2 secondary to respiratory deprssion

33
Q

CO2 blood dissociation curve:

Approximately 90% of the CO2 in transported by the blood is in the form of what?

A

HCO3-

34
Q

Conversion of CO2 to Bicarbonate in RBC’s:

What is the balancing formula that this uses

A

CO2 + H2O H2CO3 HCO3- + H+
( = carbonic anhydrase)
(H2CO3 = carbonic acid)

35
Q

Conversion of CO2 to Bicarbonate in RBC’s:

what principle is used for the to occur

A

LaChantelier’s principle

36
Q

Conversion of CO2 to Bicarbonate in RBC’s:

so explain in basic terms how this occurs

A
• CO2 leaves cell into the plasma
• then diffuses into RBC
• Once in RBC CO2 uses colonic anhydrase to combine with H2O and form carbonic acid (CO2 + H2O = H2CO3)
• then carbonic anhydrase breaks down carbonic acid into bicarb and hydrogen (H2CO3 = HCO3- + H+)
• Hb (-) charged and are buffers for H+
• HCO3- then leaves the RBC freely and another (-) needs to enter so Cl- enters
37
Q

CO2 is carried in the blood in 3 ways what are they?

A

1) in dissolved form
2) as Bicarbonate
3) chemically bonded to proteins (plasma proteins and HB)

38
Q

Chloride Shift in NON-Pulmonary Capillaries:

explain it

A
• CO2 leaves cell into the plasma
• then diffuses into RBC
• Once in RBC CO2 uses colonic anhydrase to combine with H2O and form carbonic acid (CO2 + H2O = H2CO3)
• then carbonic anhydrase breaks down carbonic acid into bicarb and hydrogen (H2CO3 = HCO3- + H+)
• Hb (-) charged and are buffers for H+
• HCO3- then leaves the RBC freely and another (-) needs to enter so Cl- enters thus maintaining electroneutrality
• the exchange of Cl- for HCO3- is the chloride shift
39
Q

Chloride Shift in NON-Pulmonary Capillaries:

the chloride shift is also called what

A

Hamburger shift

40
Q

How do you calculate the amount of CO2 in dissolved blood?

A

PCO2 x 0.067

result in mL CO2 in 100mL blood

41
Q

who’s law allows you to calculate the amount of CO2 dissolved in blood?

A

henry’s law