Effects of metabolism and distribution of carbon monoxide on blood and body stores.

LUOMANMAKIJCIMMO, AND RONALD F. COBURN. Effds of metabolism and distribution of carbon monoxide on blood and body stores. Am. J. Physiol. 2 17(Z) : 354-363. 1 969.-14C0 was administered to 3 1 anesthetized dogs and 5 normal subjects who were breathing in a closed system. 14C0 was oxidized to 14C02 at average rates of 0.30 =t (SD) 0.18 and 0.16 & 0.03 a/,/hr of the total. administered in dog and man, respectively. 14C0 oxidation rates did not change significantly as a result of increasing the 12C0 body stores Z-30 times normal or altering arterial oxygen tension from 30 to over 600 mm Hg. Rates of metabolic consumption of body 12C0 appear to be insignificant compared to rates of 12C0 production at normal levels of blood carboxyhemoglobin in man; in dog the rate of 12C0 consumption was approximately 10% of the rate of production. Evidence is presented that the distribution of CO between blood and other tissues remains constant with changes in arterial oxygen tension from 40 to 650 mm Hg, arterial CO2 tension from 28 to 65 mm Hg, and carboxyhemoglobin from 0.8 to approximately 55 % saturation. With more severe arterial hypoxemia up to 50% of the blood 14C0 shifted into extravascular tissue.