Beckman Coulter COULTER LH 750 System, Reference

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PN 4277248DD
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USE AND FUNCTION
METHOD HISTORY
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dataplot and the WBC histogram are consistent with NRBCs, the NRBC count is derived from
the WBC histogram.
COULTER IntelliKinetics Application
The LH 700 Series utilizes the COULTER IntelliKinetics application. Control of reaction
kinetics is extremely important to ensure the best performance of the automated white cell
differential and reticulocyte analysis. The IntelliKinetics application is a management tool for
the key step of system optimization when fluctuations in external variables in the laboratory,
such as temperature, occur.
The IntelliKinetics application management ensures consistent reaction kinetics. This
application intelligently manages variations in ambient laboratory temperature through
automatic adjustments to reagent reaction temperature, exposure time and delivery volumes.
Enhancements in instrument electronics, such as improved signal-to-noise ratio, work with
the IntelliKinetics application to provide better data signals for the system algorithms to
analyze. Reagent temperature control helps to increase the speed of dye uptake, thereby
improving instrument throughput. Analysis occurs under controlled conditions.
The LH 700 Series with the IntelliKinetics application shows improved separation of
populations, both for the white cell differential and reticulocytes. Cell populations made
available for analysis by the algorithms are in a more consistent location in three-dimensional
space. The IntelliKinetics application, working in concert with new algorithms, provides the
instrument with the best signals for analysis, even when the laboratory environment varies
throughout the day.
XB Analysis
Dennis B. Dorsey, MD, proposed in 1963 that the relatively constant blood cell indices could
be used to follow the performance of hematology instrumentation.
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Brian Bull, MD,
improved the technique and it is termed XB Analysis.
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XB Analysis uses a "weighted moving average" of patient sample results because Koepke and
Protextor said that QC materials "ideally should be similar in structure and in reactivity to the
patient constituent being measured. Therefore freshly drawn patient blood samples seem to
be the most appropriate [QC material]."
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Bull explains, "The analyser [sic] is considered to
be ‘in control’ when mean MCV, MCH, and MCHC determined on a batch of 20 patients by
use of the algorithm XB are within 3% of the expected mean indices of the population."
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XM Analysis
XM Analysis is a quality-control method that uses an Exponentially Weighted Moving
Average (EWMA) of CBC, Diff, NRBC and Reticulocyte Parameters and compares them with
known target values, to monitor instrument performance. The first form of moving average
statistical analysis in hematology was XB Analysis.
Extended QC
Extended QC Rules are derived from the German Quality Control Guidelines for the Medical
laboratory, known in Germany as Rili-BÄK. Rili-BÄK (Guidelines of the Federal Chamber of
Physicians), was first published in 1987 and amended in 1990 and 1993 covering clinical
chemistry, immunochemistry and other tests, but not hematology. In 2003, the guidelines
were extended to include hematology.