[Relationship of P 50 in normal subjects in physiological condition and their percentage of Hb-CO].
After a short review on the actual knowledge about the relationship between P50 of human blood in normal adults and newborns and their relative amount of Hb-CO, the Authors analyze a wide series of subjects in Whom the survey has been performed at the physiological saturations of Hb-CO. The results show that, a part from an usually high percentage of Hb-CO of still unknown origin in the newborn, the P50 of normal adults and newborns appear to be relatively stable and not shifted towards the right in spite of the progressive increasing of hypoxia induced by still physiological levels of Hb-CO.