HemoCue Glucose 201, Operating Manual

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27
Specifications
US
General
The HemoCue Glucose 201 with plasma conversion is a system for
the determination of the total amount of glucose in whole blood.
The measured whole blood value is converted to a plasma equiva-
lent glucose result which is displayed on the analyzer. The system
consists of a specially designed analyzer with specially designed
microcuvettes containing dried reagents. The microcuvette serves
as pipette, reaction vessel and as a measuring microcuvette. No
dilution is required. The glucose measurement takes place in the
analyzer, which follows the progress of the reaction and presents
the result only when the end point of the reaction has been
reached. The system is factory calibrated and needs no further
calibration. The HemoCue glucose reference system is traceable to
an Isotope Dilution Gas Chromatography - Mass Spectrometry (ID
GC-MS) method.
Intended use
Quantitative determination of glucose in whole blood using a spe-
cially designed analyzer, the HemoCue Glucose 201 with plasma
conversion. The quantitative determination of the instant blood
glucose concentration in circulation supplements the clinical evidence
in the diagnosis and treatment of patients with diabetes as well as
monitoring of neonatal blood glucose levels. The HemoCue Glucose
201 Analyzer with plasma conversion multiplies the measured whole
blood glucose value by a factor of 1.112 and displays a plasma equi-
valent glucose result. HemoCue Glucose 201 Microcuvettes are for In
Vitro Diagnostic use only, and are only to be used with the HemoCue
Glucose 201 Analyzer. For professional use only.
Theory
The chemistry method utilized by the HemoCue Glucose 201
Microcuvette is a modified glucose dehydrogenase method described
by Banauch et al.
3
A chromogen compound is added to the reagents
according to the principle outlined by Bergmeyer
4
with saponin used
for hemolyzing the erythrocytes. The absorbance is measured at two
wavelengths (667 and 840 nm) to compensate for turbidity.
Reagents
Saponin, NAD, MTT and NaF
Enzyme mix: Glucose Dehydrogenase, Diaphorase and Mutarotase
Specimen collection and preparation
Capillary, venous or arterial whole blood may be used. The anti-
coagulants EDTA or sodium heparin and the glycolysis inhibitors
sodium fluoride, sodium oxalate or potassium oxalate shall be used.
Glycolysis is a major concern in all glucose measurements. To mini-
mize the effect of glycolysis, measure the blood sample as soon as
possible after taking the sample. Samples of blood collected in vials
with recommended anticoagulants should be analyzed within 30 minu-
tes. If the blood has been kept in a refrigerator, it must be allowed to
reach room temperature 64 – 86 °F (18 – 30 °C) before analysis. Mix
all anticoagulated samples thoroughly on a mechanical mixer for at
least 2 minutes or invert the tube 8–10 times by hand before measure-
ment. Alternatively follow local recommendations. In cases of severe
hypotension and peripheral circulatory failure, glucose measurement
from capillary samples may be misleading. In such circumstances we
recommend that an analysis be made of the glucose level using venous
or arterial whole blood.