measuring CO2 level

[AHands]

Do they measure the CO2 in the blood or in the breath?

[hboyajian]

So far as I know, CO2 is measured in the blood. If the levels rise, this can be an indication of approaching breathing failure, so it is very serious, and can indicate the need for bi-pap immediately.

[Al]

They usually do an arterial blood gas by taking blood from the blood vessel deep in your wrist. It can be a bit painful but not if the tech is good at. It is the most accurate. During a sleep study they can hook you up to a monitor but it is not as accurate as the ABG.
AL.

[AHands]

taking blood from the blood vessel deep in your wrist.

Aha! I guess thats why it does not show up as a checkbox option on the standard lab order form. Thanks!