Conditions that shift the curve may affect oxygen delivery to the tissues; these effects are most pronounced at low partial pressures of oxygen:
Hb: hemoglobin; O2: oxygen gas; Hb F: fetal hemoglobin; R state: relaxed state of hemoglobin; T state: tense state of hemoglobin.
* The ferric hemes of methemoglobin do not bind oxygen, but they increase the oxygen affinity of the normal ferrous heme in the hemoglobin tetramer, shifting the curve left. With high methemoglobin levels, oxygen saturation will be low for a physiologic PaO2 due to inability of ferric heme to bind oxygen, shifting the curve right.Do you want to add Medilib to your home screen?