Abbott CELL-DYN 3200, Руководство оператора системы

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CELL-DYN ® 3200 System Operator’s Manual
3-23
9140181H—October 2001
Section 3 Principles of Operation
Hemoglobin Measurement
Overview
The HGB channel is used for the colorimetric determination of hemoglobin.
During sample aspiration, 12 µL of sample is segmented in the Shear Valve for
HGB measurement.
Before the HGB is measured, a reference value is obtained using the
CELL-DYN 3200 Diluent/Sheath in the HGB Flow Cell. A zero or blank reading
is obtained on the diluent to provide a reference to which the sample signal is
compared. Five separate blank readings are made on the diluent. The lowest and
highest are eliminated and the remaining three are averaged to give the final HGB
reference reading.
The Diluent/Sheath Syringe dispenses 1.7 mL of diluent/sheath to the Shear Valve,
transferring the HGB segment to the HGB Mixing Chamber. The HGB Lyse
Syringe then dispenses 0.9 mL of HGB Lyse into the mixing chamber. The mixture
is swirl mixed, resulting in a 1:218 dilution ratio. The HGB lyse reagent lyses the
red blood cells, converting the hemoglobin that is released by a cyanide-free
chemical process. When the lysing action is completed, a low-energy LED in the
HGB Flow Cell, attached to the mixing chamber, measures the amount of
absorbance which is proportional to the HGB concentration.
A LED with a wavelength of 555 nm is the light source. A photodetector measures
the light that is transmitted.
Five separate HGB readings are made on each sample. The lowest and highest are
eliminated and the remaining three are averaged to give the final HGB sample reading.
After the hemoglobin readings have been made, the HGB Flow Cell is rinsed with
diluent/sheath (in the normal run mode).
The reference and sample readings are compared to determine the HGB
concentration of the sample. The HGB result is expressed in grams of hemoglobin
per deciliter of whole blood. Up to two decimal places may be displayed for
hemoglobin results less than 10.0 g/dL.
HGB Parameters
The Hemoglobin is directly measured and is expressed in grams of hemoglobin per
deciliter of whole blood.
HGB Flagging
Refer to the “Operational Messages and Data Flagging” subsection of this section
for HGB flagging information.