Product Manual

Principles of Operation

N-560 Operator’s Manual 93

Functional versus Fractional Saturation

This N-560 measures functional saturation -- oxygenated hemoglobin

expressed as a percentage of the hemoglobin that can transport

oxygen. It does not detect significant amounts of dysfunctional

hemoglobin, such as carboxyhemoglobin or methemoglobin. In

contrast, hemoximeters such as the IL482 report fractional saturation

-- oxygenated hemoglobin expressed as a percentage of all measured

hemoglobin, including measured dysfunctional hemoglobins. To

compare functional saturation measurements to those from an

instrument that measures fractional saturation, fractional

measurements must be converted as follows:

functional saturation =

fractional

saturation

100 - (% carboxyhemoglobin + % methemoglobin

)

100