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Flashcards in 12. Oxygen content of blood Deck (31):
1

O2 content = (equation )

O2 content = ( O2 binding capacity x saturation) + disolved O2 = (1.34 x Hb x Sa O2 ) + ( 0.003xPaO2)
SaO2 = arterial O2 saturation
PaO2= partial pressure of O2
( 0.003xPaO2) = dissolved oxygen
(1.34x Hb ) = oxygen binding capacity

2

normally 1 g Hb bind ... O2

1.34 ml

3

normal amount of Hb in blood

15g/ dL

4

cyanosis resutls when

deoxygenateed Hb > 5g /dl

5

O2 binding capacity (calculation and result )

O2 binding capacity = normal amount of Hb in blood x 1.34 ml = 15g/ dl x 1.34ml =20.1ml O2/dL

6

O2 binding capacity (result ) normally

20.1ml O2/dL

7

Dereased Hb --> O2 content of arterial blood?

decreased

8

Dereased Hb --> O2 saturation

no change

9

Dereased Hb --> arterial pO2

no change

10

O2 delivered to tissues ( equation)

O2 delivered to tissues = cardiac output x O2 contain of blood

11

CO poisoining - Hb concntration ?

normal

12

anemia - Hb concentration ?

decreased

13

polyctemia - Hb concentration ?

increased

14

Co poisoning - % saturation of Hb ?

decreased

15

anemia - % saturation of Hb ?

normal

16

polycethemia - % saturation of Hb ?

normal

17

CO poisioning - dissolved O2 (PaO2) ?

normal

18

anemia - dissolved O2 (PaO2) ?

normal

19

polyethemia - dissolved O2 (PaO2) ?

normal

20

anemia - total O2 content ?

decreased

21

Co poiosoning - total O2 content ?

decreased

22

pollycethemia - - total O2 content ?

increased

23

CO vs O2 binding on Hb ( affinity?)

CO has x 200 grater affinity

24

Dissolved O2 in blood equation

0.003 x PaO2

25

What is the equation for oxygen content in the blood?

O2 content = (O2 binding capacity × percent saturation) + dissolved O2

26

A previously healthy patient develops blue lips and fingertips. What does this say about the value of her deoxygenated hemoglobin level?

Her deoxygenated hemoglobin must be >5 g/dL (this is cyanosis)

27

What is the normal value of the O2 binding capacity?

20.1 mL O2/dL

28

As Hb falls, what happens to each parameter (increase/decrease/unchanged): O2 content of arterial blood, O2 saturation, arterial PO2?

O2 content of arterial blood decreases, O2 saturation and arterial PO2 remain unchanged

29

• How do you calculate oxygen delivery to the tissues?

O2 delivery to tissues = cardiac output × O2 content of blood

30

A woman has CO poisoning. What are the likely levels of her Hb, %O2 saturation of Hb, dissolved O2 (PaO22 content?

Hb is normal, %O2 saturation of Hb is decreased (CO competes with O2), PaO2 is normal, and total O2 content is decreased

31

A woman has fatigue and pallor. What are the likely levels of her Hb, %O2 saturation of Hb, dissolved O2 (PaO2), and total O2 content?

Hb is decreased, %O2 saturation of Hb is normal, PaO2 is normal, and total O2 content is decreased (she has anemia)