Introduction; Intended Use; Principles Of The Test - QBC Diagnostics Star Operators & Service Manual

Intended Use

The QBC STAR™ Centrifugal Hematology System provides a diagnostic hematology profi le on venous or
capillary blood providing values for:
• Hematocrit
• Hemoglobin
• Mean Corpuscular Hemoglobin Concentration (MCHC)
• Platelet count
• White blood cell count
• Granulocyte count (% and number)
• Lymphocyte/monocyte count (% and number)

Principles of the Test

It has been known for many years that the grayish-white layer (buffy coat) that appears above the red
blood cells in a hematocrit tube contained packed layers of leukocytes (white blood cells) and thrombo-
cytes (platelets) . The QBC STAR Centrifugal Hematology System uses technologies that make it possible
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to quantify the buffy coat cells.
When the QBC STAR tube is fi lled with blood and placed into the QBC STAR instrument, the tube is spun
at a high rate of speed causing the different types of cells in the blood to separate into layers or bands from
the heaviest to the lightest. The QBC STAR System uses a special tube designed to enhance the natural sepa-
ration properties of a whole blood sample when it is centrifuged. A special coating in the QBC STAR tube
stains the two white blood cell populations (granulocytes appear orange-yellow and lymphocytes/monocytes
appear green) and the platelet layer (platelets appear yellow-orange). The ability to quantify the cells is also
enhanced by the insertion of a precision plastic fl oat into the QBC STAR tube that mechanically expands the
buffy coat layers. The hematocrit, white blood cell counts, and platelet count are directly measured from the
cell layers. The fl oat, whose density approximates the buffy coat cells, will also penetrate the red blood cell
layer. The QBC STAR hemoglobin measurement is directly related to the density of the red blood cells, and
is based on the depth of penetration of the fl oat into the red blood cell layer. Mean corpuscular hemoglobin
concentration (MCHC) is electronically calculated using the standard formula [(HGB / HCT) * 100]
The QBC STAR tube is also internally coated with anticoagulants that allow collection of capillary blood
directly from a skin puncture site.
The QBC STAR System is intended for in vitro diagnostic use.
CAREFULLY OBSERVE ALL WARNINGS AND PRECAUTIONS IN THIS MANUAL
AND ON LABELING OF QBC STAR TUBES CONCERNING THE SAFE HANDLING
L–000867(A)
1 – Introduction
WARNING
OF BLOOD AND BLOOD-DERIVED PRODUCTS.
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