ABX Pentra 80 RAB108EA, User Manual

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Description & Technology
Measuring principles
Pentra 80 - User Manual - RAB108EA
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3.2.3. HCT Measurement
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 function is a numeric integration of the MCV.
The HCT results are given as a percentage of this integration.
3.2.4. RDW calculation
The RDW ( Red cell Distribution Width ) is used to determine erythrocyte abnormalities linked
to Anisocytosis. The RDW will enable the user to follow the evolution of the width of the RBC
histogram in relation to the number of cells and their average volume.
The RDW is also a calculation from the RBC histogram.
Calculations are as followed:
– RDW = (K X SD) / MCV
With:
◆ K = system constant
◆ SD = Standard Deviation according to statistical studies on cell distribution within the RBC
histogram.
◆ MCV = Mean Corpuscular Volume of erythrocytes
3.2.5. MCV, MCH, MCHC calculation
◆
MCV (Mean Cell Volume) is calculated directly from the entire RBC histogram.
◆ MCH (Mean Cell Hemoglobin) is calculated from the HGB value and the RBC count.
◆ The mean hemoglobin weight in each RBC is given by the formula:
– MCH (pg) = HGB/RBC x 10
◆ MCHC (Mean Corpuscular Hemoglobin Contained) is calculated according to the HGB and
HCT values. Mean HGB concentration in the total volume of RBC is given by the formula:
– MCHC (g/dL) = HGB/HCT x 100
3.2.6. MPV Measurement
The MPV (Mean Platelet Volume) is directly derived from the analysis of the platelet distribu-
tion curve.
3.2.7. Pct Calculation
Thrombocrit is calculated according to the formula:
– Pct% = PLT (10
3
/mm
3
) x MPV (µm
3
) / 10 000