1. Lectures on respiratory physiology
Blood gas transport

2. DRY AIR: 21% IS OXYGEN [O2] = 21 ml/dl FO2 = 0.21
CONCENTRATION AND PARTIAL PRESSURE
O2 MOLECULES
IN AIR
DRY AIR: 21% IS OXYGEN
[O2] = 21 ml/dl
FO2 = 0.21
As PB = mm Hg
PO2 = x mm Hg
= mm Hg

3. 37oC PO2 = 0.21 x 713 mm Hg EFFECT OF WATER VAPOR PB = 760 mm Hg
PH2O = mm Hg
PDRY = mm Hg
PO2 = x mm Hg
= mm Hg

4. O2 IN PHYSICAL SOLUTION 37oC AFTER EQUILIBRATION, AIR: PO2 = 150 mm Hg
WATER
AFTER EQUILIBRATION,
AIR: PO2 = 150 mm Hg
AIR
WATER: PO2 = 150 mm Hg
AIR: [O2] = 21 ml/dl
WATER: [O2] = ml/dl
37oC
SOLUBILITY = 0.45 / 150 = ml/(dl.mmHg)

5. SOLUTION DURING EXERCISE
TRANSPORT OF O2 IN
SOLUTION DURING EXERCISE
Solubility = ml/(dl.mmHg)
PO2 in arterial blood = 100 mm Hg
[O2] = 0.3 ml/dl = 3 ml/liter
Cardiac output = 30 liters/min
Maximum O2 available = 90 ml/min
But O2 requirement is 3000 ml/min

6. Structure of hemoglobin

7. Normal cells Sickle cells

8. Oxygen dissociation curve

9. ARTERIAL
BLOOD
VENOUS
BLOOD
P50 27

10. TOTAL O2 IN BLOOD IS THE SUM
OF Hb-BOUND AND DISSOLVED O2
TOTAL [O2] = x [Hb] x % SATURATION/100
x PO2

11. TOTAL O2 IN ARTERIAL BLOOD
(1.39 x 15 x 0.97) ( x 100)
= 20.5 ml/dl

12. Effects of changing hemoglobin concentration

13. Shifting the O2 dissociation curve

14. CO-Hb DISSOCIATION CURVE
SATURATION, % O2
PARTIAL PRESSURE, mm Hg

15. Effects of CO on the O2 dissociation curve

16. Carbon dioxide is carried in the
blood in three forms
Dissolved
As bicarbonate
3. As carbamino compounds

17. Solubility of Oxygen 0.003 ml/(dl.mmHg)
Solubility of Carbon Dioxide ml/(dl.mmHg)

18. Carriage of CO2 in the blood

19. Formation of bicarbonate
CO2 + H2O H2CO3
H2CO H+ + HCO3-

20. Formation of carbamino compounds
Hb.NH2 + CO Hb.NH.COOH

21. Uptake of CO2 in systemic capillaries

22. Carriage of CO2 in the blood

23. CO2 dissociation curves

24. Comparison of O2 and CO2 dissociation curves