I am, however, concerned that Dr. Bozeman's interpretation of his own data continues the perpetuation of the myth that my investigation clearly disproved. While pulse oximeters overestimate the arterial hemoglobin oxygen saturation, the amount is not equal to the COHb level. Thus, while pulse oximeters do overestimate true arterial hemoglobin oxygen saturation, it is by an amount that is less than the COHb level. Dr. Bozeman's data confirm my finding in this regard. It should not be surprising that the two values are not equal.
Pulse oximeters rely on the differential absorption of light to make their measurement.
The absorption spectra of carboxyhemoglobin and oxyhemoglobin are not identical at the wavelengths utilized. Confirmation of the pulse oximetry gap in carbon monoxide poisoning. Pulse oximetry in severe carbon monoxide poisoning. 1100 Ninth Ave. 2000 American College of Chest Physicians in association with The Gale Group and LookSmart.