Temperature and Oxygen Transport

Overview
  • Increased temperatures of blood result in a reduced affinity of hemoglobin for oxygen and thus a rightward shift of the Oxygen-Hemoglobin Dissociation Curve described in Oxygen Transport. Consequently, higher temperatures result in enhanced unloading of oxygen by hemoglobin. This relationship is helpful as metabolically-active peripheral tissues such as exercising skeletal muscle which often display supra-normal temperatures. Because of this increased temperature, oxygen unloading by hemoglobin is enhanced in these metabolically-active tissues, thus improving oxygen transport to areas which require it most.
Modulation of the Oxygen-Hemoglobin Dissociation Curve
A variety of environmental factors can shift the Oxygen-Hemoglobin Dissociation Curve. Effects which are associated with increased peripheral tissue metabolism, such as reduced pH, increased CO2, increased temperature, shift the curve to the right, reducing hemoglobinâ€s affinity for oxygen and thus improving oxygen unloading. Chronic hypoxia increases the bloodâ€s concentration of 2,3-DPG which also shifts the curve to the right. The presence of HbF and carbon monoxide (CO) shift the curve to the left, increasing the oxygen affinity of hemoglobin.