RADIOMETER ABL800 FLEX - Page 136

5. Performance characteristics ABL800 FLEX Reference Manual
Interference tests, Continued
ctBil sensitivity
for MCHC
variations
(continued)
∆c
c
tBil
tBil
0.58
1 0 350
=−
−
×
−
=+
.
.
58
18
0071 And ∆ctBil = 0.071 x 400 = 28 µmol/L.
If the reference value for Hct is known, it is possible to correct the displayed ctBil
value, using the following equation:
cc
c
tBil(corrected) tBil(displayed
tHb(displayed)
Hct(reference)
=×
−×
−
)
.1 00301
1
ctHb is measured in g/dL.
ctBil is slightly sensitive to pH deviations from the nominal value of pH = 7.4.
ctBil sensitivity
for pH changes
The following table shows the changes in ∆ctBil compared to the value at pH =
7.4.
Sample Type
ctHb
g/dL
Nominal
ctBil
µmol/L
∆
ctBil
(7.4→7.1)
µmol/L
∆
ctBil
(7.4→7.9)
µmol/L
Adult/fetal plasma 0 0 3 0
Adult blood, sO
2
= 100 % 15 0 0
−5
Fetal blood, sO
2
= 100 % 15 0
−13
4
Adult/fetal plasma spiked with
unconjugated bilirubin
0 400
−2 −1
Adult/fetal plasma spiked with
conjugated bilirubin
0 400 9
−11
Adult blood spiked with un-
conjugated bilirubin, sO
2
= 100 %
15 400 10
−26
Fetal blood spiked with un-
conjugated bilirubin, sO
2
= 100 %
15 400
−4 −16
Adult blood spiked with conjugated
bilirubin, sO
2
= 100 %
15 400 14
−35
Fetal blood spiked with conjugated
bilirubin, sO
2
= 100 %
15 400 0
−26
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