I work at St Vincent Hospital in Leadville, CO (10,200 feet above sea level).  We have many of the Uranium Miners come to us to have Arterial Blood Gases, PFTs, and x--rays.  Our policy is the patient must be at Altitude at least 8 hours prior to any ABGs.  The ABG is only affected by the PO2 which is 60 to 80 instead of 80 to ...