Yeah, and if there was a real pressing need to get an more accurate number, you would get an arterial blood gas. Pulse oximetry is for monitoring change. When

Yeah, and if there was a real pressing need to get an more accurate number, you would get an arterial blood gas. Pulse oximetry is for monitoring change. When a critical value is needed for medical intervention, such as a decision to put in a breathing tube, tests like arterial blood gas has are used.