Beckman Coulter COULTER LH 750 System, Справочник

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PN 4277248DD
1-3
USE AND FUNCTION
QUALITY CONTROL (QC)
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1.3 QUALITY CONTROL (QC)
Your laboratory can use these QC techniques with the LH 700 Series:
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Daily instrument checks
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Commercial or Patient Controls
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Delta checks
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XB Analysis
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Extended QC
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XM Analysis
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Interlaboratory Quality Assurance Program (IQAP)
Quality Assurance includes routine maintenance and service in conjunction with the use of
controls and calibrators. The combination of these methods provides the assurance of
complete quality control and should be applied separately or in combination, in accordance
with your laboratory, state and federal protocols.
1.4 METHOD HISTORY
Development
W.H. Coulter (1956) describes the Coulter Principle:
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A suspension of blood cells is passed thru [sic] a small orifice simultaneously with an
electric current. The individual blood cells passing thru the orifice introduce an
impedance change in the orifice determined by the size of the cell. The system counts the
individual cells and provides cell size distribution. The number of cells counted per
sample is approximately 100 times greater than the usual microscope count to reduce the
statistical error by a factor of approximately 10 times.
This substantial improvement in precision over previous methods helped to establish the
erythrocyte count as a sensitive index of erythropoietic dyscrasia, particularly when
considered together with Hct and Hgb measurements.
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The COULTER COUNTER Model S analyzer was the first instrument that automated
simultaneous multiparameter measurements on blood. Brittin et al., Gottmann, and Hamilton
and Davidson, reviewed the performance and clinical value of the Model S.
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Refinements of the COULTER COUNTER analyzer to provide accurate size (volume)
distribution data led to a reawakening of interest in pathological erythrocyte size distribution,
first sparked by Price-Jones.
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Among the advantages offered by the Coulter method of counting and sizing was the ability
to derive an accurate Hct measurement by summing the electronic volume of erythrocytes.
England et al. speculated that electronic Hct measurements did not contain the trapped
plasma error of centrifugal Hct measurements.
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Bull et al. described the use of a COULTER COUNTER analyzer for counting thrombocytes.9
This method, useful as it was, depended on preparing thrombocyte-rich plasma to avoid
counting erythrocytes as thrombocytes. Mundschenk et al. and Schulz and Thom discussed
the possibility of counting thrombocytes in the presence of erythrocytes and classifying them