O2 Solubility In Blood And Temperature Correction Factors For Po2
Tonometry of 100 paired samples of blood and measurement of Po2 before and after warming in a sealed syringe showed that the relative solubility of O2 (αB/αHh2O) in fully saturated blood is constant at all temperatures between 24.5 and 38 C, i.e., fully saturated blood appears to behave as a dilute aqueous solution. When Po2 is kept constant during cooling the relative increase in dissolved O2 in blood is the same as with water. Thus, when cooling from 38 to 20 C the increase in dissolved O2, if Po2 is kept constant, is 31%. Correction factors for the effect of temperature on Po2 of blood warmed to 38 C can be based on ratios of αHh2O38/αHh20T. These factors were found to give adequate correction at O2 tensions above 250 mm Hg. Inaccuracies were found when previously proposed factors were applied to blood having a Po2 of 300 mm Hg. These results were interpreted as showing that blood is essentially fully saturated at a Po2 of approximately 250 mm Hg.
(With the Technical Assistance of A. Murphy and A. Seifen)
relative solubility; agr; hypothermia; hemoglobin; dissociation; tonometry; O2 electrode; physiologic shunt
Submitted on December 23, 1963