What happens to CO2 in hypoxemic respiratory failure?

[@ravis2618]

Spot on.This is exactly what I wanted to know.

[@CarlosPires-du3ps]

could you elaborate more with the last four mechanisms. How shunt does not cause hypercapnia? and why dead space does not cause hypoxemia?

[@Luchaux]

Shunt does not cause hypercapnia because the brainstem reacts to hypoxemia thus induces hyperventilation which will more likely cause hypocapnia