Systemic Oxygenation

CaO₂ = (1.34 x [Hb] x SaO₂) + (0.003 x PaO₂)

The normal arterial O₂ content is 20 ml/dL and only 1.5% represents dissolved O₂.

CvO₂ = (1.34 x [Hb] x SvO₂) + (0.003 x PvO₂)

The normal venous O₂ content is about 15 ml/dL and less than 1% represents dissolved O₂.

The difference between the arterial and venous O₂ content is 5 ml/dL or 50 ml/L, which means that 50 ml of O₂ is extracted from each liter of blood flowing through the capillaries.