Oxygen and Carbon Monoxide Equilibria of Human Adult Hemoglobin at Atmospheric and Elevated Pressure

Adult human hemoglobin has been shown to have an affinity for carbon monoxide 218 times that for oxygen at 37°. There is no change in the relative affinity between pH 6.8 and 8.8. The same value was obtained with whole blood and with concentrated undialyzed hemoglobin solutions. Measurements made at atmospheric pressure were identical with those at increased total pressure up to 21.4 atmospheres absolute. Substitution of helium for nitrogen as inert gas did not alter the value. The relative affinity constant K is increased by 2 per cent by a decrease in temperature of 1° C.