oxygen in blood?

Question

A normal subject has an arterial PO2 of 13.3 kPa (100 mm Hg) and a mixed venous PO2 of 5.3 kPa (40 mmHg). Fully saturated hemoglobin carries 1.34 ml O2 per gram (at STP). The hemoglobin concentration for this subject is 145 g per liter of whole blood and the oxygen solubility is 0.225 ml l-1 kPa-1 (0.03 ml/mm Hg/liter of blood). Using the data provided calculate: a) The quantity of oxygen dissolved in the arterial blood. b) The quantity of oxygen dissolved in mixed venous blood. c) The quantity of oxygen combined with hemoglobin in the arterial blood. d) The quantity of oxygen combined with hemoglobin in mixed venous blood. e) The total oxygen content of the arterial blood. f) The total oxygen content of mixed venous blood.

Answer 1

a) 3 ml/L
b) 1.2 ml/L
c) 194.3 ml O2/L assuming the subject's blood is fully saturated. But at 100mm Hg, the subject is 97.7% saturated, so = 189.8 ml/L
d) At 74.9% saturated, venous blood contains 145.5 ml O2/L.
e) 192.8 ml O2/L
f) 146.7 ml O2/L

Answer 2

Oxygen content can be measured directly or calculated by the oxygen content equation:

CaO2 = Hb (gm/dl) x 1.34 ml O2/gm Hb x SaO2 + PaO2 x (.003 ml O2/mm Hg/dl)

Answer 3

Are you in need of someone to do your home work? You should know the formula and can work this out for yourself.