horiba ABX MICROS ES60, Руководство пользователя

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Description & Technology
User Manual - RAB237AEN 3–9
3.3.2. HGB
◆
The hemoglobin measurement is based on a startup cycle. This cycle includes an hemoglobin blank
test sequence which includes 2 hemoglobin blank measurements. Each analysis cycle run after
start-up also has a HGB blank measurement which is compared to the initial start-up HGB blank.
Each analysis cycle run thereafter compares the HGB blank reading to the previous cycle HGB
blank reading.
◆
During the WBC analysis cycle, 0.5ml of ABX Lyse reagent is added to 2.05ml of diluted blood in
the WBC chamber. The Lyse reagent contains potassium ferricyanide [Fe(Cn)]K, and potassium
cyanide [KCN]. This lysing reagent breaks down the RBC cell membrane and releases the
hemoglobin within the RBC.
◆
The hemoglobin then combines with the potassium cyanide to form a chromogenous
cyanmethemoglobin compound. This chemical compound is measured by spectrophotometry,
through the optical pathway in the WBC chamber. The light wavelength of measurement is at
550nm.
Results : HGB results are given as such:
HGB = Log(Blank value/Sample value) x Calibration Coefficient.
3.3.3. HCT
◆
The hematocrit is a combination measurement of electronic pulses and mathematical calculations.
All the RBC pulses are grouped into various sizes. Each group pulse height is then averaged. All
the pulse height averages are then averaged one final time for a mean average of all the RBC pulse
heights. This is a function of the numeric integration of the MCV. Results are given as a percentage
of this integration.
3.3.4. MCV, MCH & MCHC
◆
MCV (Mean Cell Volume), is calculated directly from the entire RBC histogram.
◆
MCH (Mean Cell Hemoglobin), is calculated from the hemoglobin value and the RBC count.
Calculations are as follows:
MCH (pg) = HGB/RBC x 10
(pg) Picograms
◆
MCHC (Mean Corpuscular Hemoglobin Concentration), is calculated according to the hemoglobin
and hematocrit values. Calculations are as follows:
MCHC (g/dl) = HGB/HCT x 100
3.3.5. RDW
◆
The RDW (Red cell Distribution Width) is used to determine erythrocyte abnormalities linked to
anisocytosis. The RDW will enable you to follow the evolution of the width of the RBC histogram
in relation to the number of cells and their average volume. This is also a calculation of the RBC
histogram. Calculations are as follows:
RDW (%) = K x SD/MCV
K: Calibration coefficient for RDW.
SD: Standard Deviation according to statistical studies on cell distribution.
MCV: (Mean Cell Volume) of the erythrocytes.
3.3.6. MPV
◆
The MPV (Mean Platelet Volume), is directly calculated from the platelet histogram distribution
curve. This calculation is almost the same as the MCV.
3.3.7. PCT
◆
Thrombocrit (Plateletcrit), is calculated according to the formula:
PCT% = PLT (10
3
/mm
3
) x MPV (µm
3
) / 10 000