Medonic CA530, User Manual

Page: 81 / 108

03-11-24 81
10 Calibration and controls
10.1 Introduction
The instrument has been calibrated at the factory. This applies to all measured
parameters. As the instrument has a mechanical fixed metering unit and fixed me-
chanical micro-volumes; the numerical calibration for the RBC/WBC and PLT
are basically stable at all time. Good laboratory practice however, requires regular
checks and calibration of the measured parameters.
The software calibration factors for all measured parameters can be changed by
the user within a large range. This is done to match other analyzers, methods or
applications in the laboratory.
It is advisable that the performance of the CA620/530 system is checked daily
(not calibrated) with a certified control blood. Special attention should be paid to
the calculated MCHC parameter (MCHC = HGB/(MCV*RBC)).
Recommended calibration periods are twice a year with an 'Hematology Blood
Calibrator' certified by Boule.
The MCHC parameter can be used as an excellent check on the relation between
HGB and HCT. This parameter should be in the range of 30 - 37 g/dl. Daily
mean values of the samples should always be 32 - 36 g/dl.
RBC, WBC and PLT
Calibration of the above-mentioned parameters is done at the factory with refer-
ence standard instruments and volumetric measuring methods. The metering
tube is mechanically constant and will remain stable.
MCV
Calibration of the MCV parameter may be necessary if the temperature environ-
ment of the laboratory has changed significantly. (>
∆
10 °C)
10.2 Use of Calibrators and Controls
The calibration of the instrument can be verified by counting pre-assayed com-
mercial reference control samples or by counting retained patient samples with
known reference values from another “reference” instrument.
To ensure the accuracy of the values obtained whenever commercial controls are
used:
1. Always re-suspend according to the manufacturer's recommendations.
2. Never use an open vial longer than recommended by the manufacturer or
subject any vial to excessive heat or agitation.
3. Verify the condition of controls when received. Make sure that they are cold
and not leaking.
4. Do not use a commercial control for calibrating the instrument, use only
“Calibrators”.
Important
Do not calibrate the MCV
parameter using commer-
cial controls with values
given for other analyzers,
unless approved by Boule.
Not following this might
lead to incorrect MCV val-
ues on processed samples
Important
Use the special ID func-
tion to identify the specific
control blood. See
Print
control blood id:s on
page 70.
Not doing so might lead to
incorrect WBC values.
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