Bayer HealthCare Rapidlab 800, Operator'S Manual

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The CO-oximeter (CO-ox) module detects and indicates concentrations of
sulfhemoglobin greater than 1.5%.
Hemoglobin derivatives have characteristic absorbance spectra; that is, each
derivative absorbs light differently at different wavelengths. Similarly, interfering
substances also absorb light at known wavelengths.
The spectral absorption method determines concentration using matrix equations.
For each substance or fraction, the absorbance at a specific wavelength is equal to
the product of the path length, concentration of the fraction or substance, and the
molar absorptivity or the extinction coefficient for that substance, as shown in the
following equation:
A
x
ε
1
C
1
2
C
2
. . .
n
C
n
where A
x
is the absorbance at a specific wavelength,
ε
is the major extinction
coefficient for that fraction or substance at a specific wavelength, and C is the
concentration of the substance.
These equations are based on the work of VanAssendelft
33,34
and Benesch,
Benesch, and Yung.
35
The 800 systems CO-oximeter (CO-ox) module measures the light of whole blood
at several wavelengths. Based on this, the CO-ox module measures and reports
total hemoglobin and other related quantities. The CO-ox module also detects the
presence of interfering substances such as bilirubin, cyanmethemoglobin, turbidity,
and dyes.
The CO-ox module is connected to the base model, which supplies power to the
module. The CO-ox module contains measuring, fluidic, and electronic
components. It uses the sample entry port, reagents, and waste components of the
base model.
The measurement system for the CO-ox module detects and quantitates the
analytes present in the sample. The measurement system has the following
components:
the lamp
the illumination optics (lenses and filters)
the fiber optic coupler
the sample chamber