How does sleep apnea affect arterial blood gas?

When taken?: If the blood gas is taken while the person is awake, the results are likely to be normal unless there is an underlying breathing or lung disorder. If taken while asleep, it could show a low oxygen level, a higher than normal co2 level, but these changes are constantly fluctuating on a breath by breath basis.

Can temporarily lower 02: When someone is having apnea they stop breathing and this can cause a decrease in the blood oxygen and an increase in the blood carbon dioxide. Once they start breathing again usually this corrects itself fairly quickly.