In Vivo Pulse Oximeter Validation Study

Hypoxia was induced to different and stable levels of oxyhemoglobin saturation (between 70-100%) by having subjects breathe mixtures of nitrogen, air, and carbon dioxide controlled by the study physician by adjusting gas flows with valves according to breath-by-breath estimates of oxygen saturation calculated from end-tidal PO2 and PCO2 displayed on a screen using LabVIEW 2015