RADIOMETER ABL800 FLEX - Page 80

4. User-defined corrections ABL800 FLEX Reference Manual
Correction factors for oximetry parameters and bilirubin,
Continued
ctBil
The following recommendations apply to ctBil:
Item Description
Units
µmol/L
Sample Radiometer recommends that human plasma or serum is used
with pH ≈ 7.4 (the analyzer reading). Zero point sample could
be adult sample (ctBil ≈ 0 µmol/L) and maximum point could
be an unconjugated bilirubin sample with
ctBil ≈ 300 - 400
µmol/L.
Averaging repeated measurements on samples from different
donors gives an optimized accuracy of the correction.
Averaging repeated measurements on samples from the same
donor also improves the accuracy.
Commercial bilirubin standards can interfere with bilirubin
measurement because they may have an absorbance spectrum
different from that of human plasma.
Slope 0.5 - 1.5
Offset
± 100
FO
2
Hb and
FHHb
The units for FO
2
Hb and FHHb are [Fraction].
After the user-defined corrections of the parameters
sO
2
, FCOHb and FMetHb
have been carried out, FO
2
Hb and FHHb are automatically calculated using the
formulae stated below, since the sum of the fractions
FCOHb, FMetHb, FO
2
Hb
and
FHHb as defined must be equal to 1.0:
FO Hb:
2
FO
2
Hb = (1 − FCOHb − FMetHb) × sO
2
FHHb:
FHHb = (1 − FCOHb − FMetHb) × (1 − sO
2
)
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