A&p2 Unit 3/4

Front 1

3 different ways gases can exist in solution

Back 1

-dissolved state in solution
-combined w/ proteins in solution (Hgb)
-chemically modified (CO2 combines w/ water to form carbonic acid)

Front 2

normal oxygen consumption at rest

Back 2

VO2=250ml/min
(this is how much is delivered to the tissues per minute)

Front 3

normal cardiac output at rest

Back 3

5L/min

Front 4

how many mls of O2 is delivered to the tissues for every Liter of blood?

Back 4

250ml/min / 5L/min=50ml

Front 5

How many mls of oxygen per 100ml of blood is passing through the tissues?

Back 5

5ml O2/100ml
(50ml O2/1000ml)

Front 6

what percentage of oxygen delivered to the tissues is in the dissolved state?

Back 6

3% of the 5mls=0.15mls of O2

Front 7

what accts for the partial pressure of the gas?

Back 7

the gas that is physically dissolved

Front 8

volume of oxygen dissolved in the plasma is r/t to its ______?

Back 8

solubility coefficient

Front 9

solubility coefficient for oxygen in plasma at normal body temp?

Back 9

0.003 mlO2/100ml blood/torr

Front 10

volume of oxygen dissolved in the plasma is directly proportional to ?
And whose law is this?

Back 10

the partial pressure of oxygen
henry's law

Front 11

calculate the amt of oxygen dissolved in the plasma of arterial blood?

Back 11

Sol coeff of O2 x PaO2=
.003ml/100ml blood/torr x 100
=
0.3ml O2/100ml blood

Front 12

calculate the amt of oxygen dissolved in plasma of mixed venous blood?

Back 12

sol coeff of CO2 x PvO2=
.003ml/100ml blood/torr x 40=
0.12ml O2/100ml blood

Front 13

how do you determine the amt of oxygen delivered to tissue in dissolved state?

Back 13

amt of oxygen dissolved in plasma of arterial blood -
amt of oxygen dissolved in plasma of mixed venous

Front 14

actual calculation of the amt of oxygen delivered to tissues in dissolved state?

Back 14

0.3ml/100ml blood -
0.12 ml/100ml blood=
0.18ml O2/100ml blood
(amt delivered to the tissues from plasma of every 100mls of blood flowing thru systemic capillaries)

Front 15

how do you come up with 3% for the amt of oxygen delivered to tissues in dissolved state?

Back 15

at rest, deliver 5ml of O2 for every 100ml/blood delivered to tissues & 0.18ml of this O2 is from plasma
(0.18ml O2/100ml blood
--------------------------------
5 ml O2/100 ml blood )
=.036---3.6%= approx 3 %

Front 16

if breathing 100% at sea level, how much oxygen is dissolved in plasma?

Back 16

1. determine PAO2
Patm-Ph2o-PACO2=673 torr
2. PAO2 x sol coeff:
673 x .003 ml/O2/100ml blood/torr=2.01 ml O2/100ml
(if all of this dissolved oxygen could be delivered to tissue, then approx 40% of tissues oxygen need can be met by the oxygen dissolved in plasma when breathing 100% oxygen)

Front 17

how much oxygen is dissolved in plasma if breathing 100% at 2 atms?

Back 17

2(760)-47-40= PaO2 of 1433 torr
1433 x .003ml/100ml/torr=4.3 ml O2/100ml blood
(80% of tissue needs could be met by doing this)

Front 18

when does the amount of oxygen being delivered to the tissues from the dissolved state become significant?

Back 18

-when breathing oxygen at high pressure

Front 19

how does administering high FIO2 benefit pt's?

Back 19

-increasing amt of O2 that can be delivered from the dissolved oxygen to the tissue
-increasing the initial O2 pressure gradient (imp for gas equilibration across pulm and systemic memb)

Front 20

how much of the oxygen delivered to the tissue per min is combined w/ Hgb?

Back 20

97%

Front 21

3 steps needed in order for oxygen to combine w/ Hgb

Back 21

1. oxygen diffuses across the pulm membrane and becomes dissolved in the plasma
2. oxygen diffuses from plasma and into the fluid of the RBC
3. oxygen combines with the Hgb molecules in the RBC

Front 22

as oxygen becomes dissolved in plasma and the partial pressure rises, this creates a gradient b/t which two things?

Back 22

the plasma and fluid of RBC

Front 23

what increases oxygen binding to Hgb?

Back 23

higher partial pressures of oxygen

Front 24

what type of bond does oxygen form w/ hgb?

Back 24

reversible

Front 25

oxygen combined w/ Hgb =

Back 25

oxyhemoglobin

Front 26

if 100% saturated, each Hgb molecule is able to combine w/ how many molecules of oxygen?

Back 26

4 (8 total)

Front 27

composition of Hgb molecule

Back 27

-globulin portion
-4 heme groups, each having a ferrous iron (Fe+2)

Front 28

oxygen is specifically binding to iron in what state?

Back 28

ferrous only (2+)

Front 29

unoxygenated hgb is called ?

Back 29

deoxygenated hgb or deoxyhemoglobin

Front 30

the maximum amt of oxygen that can combine w/ hgb in 100ml of blood is termed?

Back 30

oxygen carrying capacity of hgb

Front 31

what does the oxygen-carrying capacity depend on?

Back 31

the amt of hgb present in the blood

Front 32

normal hgb concentration

Back 32

15gm% ( 15gm of Hgb/100ml blood)

Front 33

how many mls of oxygen can combine w/ 1gm hgb?

Back 33

1.34 ml O2/ gm Hgb

Front 34

what is oxygen carrying capacity in lab setting w/ pure Hgb (no impurities present)

Back 34

1.39 ml O2/gm Hgb

Front 35

normal oxygen carrying capacity for physiological man w/ Hgb of 15gm%?

Back 35

20.1 ml O2/100ml blood
(20.1ml of O2 will combine w/ Hgb in every 100ml of blood)

Front 36

if you change the Hgb concentration, what else will change?

Back 36

the oxygen carrying capacity

Front 37

2 things you have to know to determine Hgb saturation

Back 37

-amt of oxygen combined w/ hgb
-the oxygen carrying capacity of Hgb

Front 38

formula to determine the oxygen carrying capacity of Hgb (% saturation)

Back 38

(O2 combined w/ Hgb/O2 carrying capacity of Hgb) x 100

Front 39

what shows the relationship b/t the oxygen tension of the blood and the % saturation of Hgb w/ oxygen?

Back 39

oxyhemoglobin dissociation curve

Front 40

is the % saturation of Hgb w/ oxygen linearly related to the partial pressure of oxygen in the blood?

Back 40

no, it is a S-shaped or sigmoid shaped curve

Front 41

term used for mls of oxygen per 100ml of blood

Back 41

volumes percent

Front 42

does volumes percent or % saturation vary w/ the amt of Hgb present?

Back 42

volumes percent

Front 43

when using a volume percent of 20 for 100% saturation, this is only true when the Hgb is ?

Back 43

15gm%

Front 44

how do youcalculate volumes percent?

Back 44

oxygen carrying capacity x Hgb

Front 45

a normal PaO2 of 100, has a % saturation of ?
(arterial blood)

Back 45

97.5%

Front 46

how do you find out the amount of oxygen bound to Hgb in arterial blood?

Back 46

a. 1.34ml O2 x 15gm/100=20.1(amt of O2 combined w/ Hgb in 100mls)
b. Oxy carrying capacity x % sat of arterial blood
(20.1 x .975=19.6)
**20 ml O2/ 100ml of blood**

Front 47

how do you find out the oxygen content of the arterial blood?

Back 47

add the amt dissolved and the amt bound to Hgb
(19.6 + 0.3=19.9 ml O2/100ml)

Front 48

what would the arterial oxygen tension need to be to get 100% saturation of arterial blood?

Back 48

250 torr

Front 49

does hyperventilating add significant amts of oxygen to the arterial blood?

Back 49

no

Front 50

what is the oxygen saturation of mixed venous blood as it returns to the pulm capillaries?

Back 50

75%

Front 51

calculate the oxygen carrying capacity of Hgb in mixed venous blood?

Back 51

20.1 x 0.75=15
(15 mls O2 bound to Hgb/100ml blood)

Front 52

oxygen content of mixed venous blood?

Back 52

15.1 + 0.1= 15.2

Front 53

what is the utilization coefficient?

Back 53

that fraction of oxygen that has been released from Hgb to the tissues

Front 54

utilization coefficient of the arterial blood at rest?

Back 54

25%
(5ml O2/100ml blood
--------------------------------
20 ml O2/100ml blood)

Front 55

the utilization coefficient depends on what?

Back 55

the metabolic activity of tissues and organs
(greater the metabolic activity, greater the utilization coefficient)

Front 56

utilization coefficient of the blood in the coronary sinus at rest?

Back 56

75%
(myocardium extracts 15ml of O2 per 100ml blood)

Front 57

how do we increase the amount of oxygen available to the cardiac muscle?

Back 57

we must increase perfusion b/c we are already releasing 75% at rest

Front 58

which is more important:
% saturation or arterial oxygen tension in the blood

Back 58

oxygen tension

Front 59

the pulse ox provides us with a way to do what?

Back 59

noninvasively estimate the arterial oxygen tension

Front 60

3 parts to the oxyhemoglobin dissociation curve

Back 60

steep middle portion
area b/t flat upper and steep
flat upper portion

Front 61

steep middle portion of the curve corresponds to what?

Back 61

oxygen tensions at the tissue level

Front 62

oxygen tensions of the steep middle portion of the curve range from ?

Back 62

40 torr to about 15/20 torr

Front 63

what is the significance of the steep middle portion of the deoxyhgb curve?

Back 63

a relatively small change in pressure causes a relatively large change in oxygen attached to hgb

Front 64

a small decrease in pO2 in steep middle portion of curve, also causes a decrease in?

Back 64

volume percent of O2 or percent saturation d/t a relatively large amt of oxygen being unloaded from hgb to the tissue

Front 65

how does the steep middle portion of the curve facilitate oxygen delivery to the tissues?

Back 65

it allows us to drop our pressure slowly so that we maintain our gradient which continues to allow oxygen to move into the tissues but still unload a large amt of oxygen

Front 66

what is the significance of the flat upper portion of the curve?

Back 66

that the pO2 can drop significantly (from 100-60) but the % saturation remains relatively high

Front 67

what serves as a safety factor as it r/t the amt of oxygen bound to hgb?

Back 67

the flat upper portion of the curve that asllows significant drops in pO2 without reducing the % saturation significantly

Front 68

shifting the deoxy curve to the left and right, has little impact on which parts?

Back 68

flat upper or very beginning

Front 69

the greatest repositioning of the deoxy curve will be seen where?

Back 69

at the steep portion, this occurs to pO2 seen at the tissue level...greatest impact is on oxygen delivery to tissues

Front 70

a shift to the right of the deoxy curve results from?

Back 70

Hgb's decreased affinity for oxygen, which means more will be given up to tissues

Front 71

what is the significance of the part of the curve b/t the steep and flat upper part?

Back 71

as blood is returning from tissues to pulm cap, mixed venous blood oxygen tension goes from 40-60, saturation goes from 75%-90%.
Fair amt of unloading of oxygen has already occurred, but there is still a PG left to allow the rest to unload (60-100)

Front 72

how could you double oxygen delivery to the tissues?

Back 72

shift the curve to right

Front 73

factors shifting the curve to the right by decreasing Hgb's affinity for oxygen

Back 73

-increase CO2 tension
-increase in H+ conc.
-increased temp
-increase in 2,3 DPG/ 2,3 BPG
-sickle cell anemia

Front 74

the effect that H+ has on Hgb's affinity for oxygen is known as the?

Back 74

Bohr effect

Front 75

3 things that can increase H+ concentration causes shift to the right

Back 75

ketoacidosis
lactic acid
exogenous acids from meds

Front 76

what is produced in the RBC as a result of glycolytic metabolism?

Back 76

2,3 DPG/BPG
(diphosphoglycerate/bis)

Front 77

what happens to 2,3 DPG production during the first hour of strenous exercise?

Back 77

it increases, which is beneficial b/c it decreases Hgb's affinity for oxygen, so it can be released to tissues which need it

Front 78

a shift to the left results from?

Back 78

increase in Hgb's affinity for oxygen

Front 79

shift to the left causes:

Back 79

less oxygen to be given up to the tissues

Front 80

factors shifting curve to the left by increasing Hgb's affinity for oxygen are:

Back 80

decrease in CO2
decrease in H+
decrease temp
decrease 2,3 DPG
increase in fetal Hgb
increase in methemoglobin
increase in carboxyhemoglobin

Front 81

how was the Bohr effect first presented to us?

Back 81

as Hgb effect due to CO2, now we understand it has Hgb effect due to H+ ions

Front 82

what is directly causing the change in affinity of Hgb for oxygen?

Back 82

the release of H+ in response to the increased CO2

Front 83

an increase in CO2/H+ decreases Hgb's affinity for oxygen, curve is shifted to ____, and the shift occurs where?

Back 83

left, tissue level

Front 84

a decrease in CO2/H+ increases Hgb's affinity for oxygen, curve is shifted to _____, and this occurs where?

Back 84

right, level of the lungs

Front 85

events occurring in systemic & pulm capillaries in response to CO2 changes is referred to as?

Back 85

the Bohr effect

Front 86

what determines the relative position of the oxyhemoglobin dissociation curve? (whether it has shifted to right/left)

Back 86

P50 test

Front 87

what is P50?

Back 87

the PaO2 at which the Hgb is 50% saturated with oxygen (or 50% is in deoxygenated state)

Front 88

Normal P50 of arterial blood

Back 88

26-27 torr

Front 89

when P50 is increased, the curve is?

Back 89

shifted to right, decreased affinity of Hgb for oxygen, more to tissues

Front 90

when P50 is decreased, the curve is?

Back 90

shifted to left, increased affinity of Hgb for Oxygen, less to tissues

Front 91

why is the venous curve shifted to the right?

Back 91

b/c of lower pH and PCO2 is higher

Front 92

what is the pH and CO2 like in the arterial blood...generally speaking?

Back 92

increased pH and decreased CO2

Front 93

what is the binding site of CO?

Back 93

same binding site as oxygen on Hgb, ferrous site

Front 94

how could you treat CO poisoning?

Back 94

100% oxygen b/c you are increasing odds that oxygen will bind d/t increasing gradient
-could add a little CO2 to increase ventilation
-hyperbaric chamber at 2atms

Front 95

how much more of an affinity does Hgb have for CO than Oxygen?

Back 95

210 times greater

Front 96

carbon monoxide + Hgb=

Back 96

carboxyhemoglobin

Front 97

color of carboxyhemoglobin

Back 97

cherry pink

Front 98

2 ways that CO decreases oxygen delivery to the tissues

Back 98

-it occupies some of the binding sites normally occupied by oxygen
-it increases affinity of Hgb for those oxygen molecules that are bound to Hgb, so makes it difficult to release

Front 99

in pt exposed to CO, what will their PaO2 look like?

Back 99

normal b/c CO doesn't interfer with ability of oxygen to dissolve in plasma

Front 100

what law explains why PaO2 levels are normal in someone exposed to CO?

Back 100

dalton's law of partial pressure:
each gas in a mixture exerts a pressure independent of other gases in mixture

Front 101

in CO exposure, what happens to total oxygen content of the blood?

Back 101

decrease in total content

Front 102

what are readings like of someone's pulse ox that was exposed to CO?

Back 102

normal or false high