Effect of carboxyhemoglobin on measured oxygen saturation by pulse oximetry
Effect of carboxyhemoglobin on measured oxygen saturation by pulse oximetry
SpO2 and cooximetry versus carboxyhemoglobin (COHb) at FiO2 = 1.0. SpO2 consistently overestimates O2 saturation in the presence of COHb. At COHb = 70 percent, SpO2 is still roughly 90 percent, while oxyhemoglobin has fallen to 30 percent.
FiO2: fraction of inspired oxygen; O2: oxygen; SpO2: standard pulse oximetry.