NOVA BIOMEDICAL Stat Profile PRIME, Инструкция по эксплуатации

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B-4
Prime CCS Instructions for Use Manual
B.1.4 Partial Pressure of Oxygen ( P O
2
)
Definition of PO2
The partial pressure (tension) of oxygen in solution is
defined as the partial pressure of oxygen in the gas phase
in equilibrium with the blood. P O
2
provides an indication of
the availability of oxygen in inspired air.
Principle of P O
2
Measurement
P
O
2
is measured amperometrically by the generation of a
current at the sensor surface. As oxygen diffuses through
a gas permeable membrane, the oxygen molecules are
reduced at the cathode, consuming 4 electrons for every
molecule of oxygen reduced. This flow of electrons is then
measured by the sensor and is directly proportional to the
partial pressure of oxygen.
B.1.5 Hematocrit
Hematocrit is defined as the percentage of red blood cells
to the total blood volume and can be obtained by measuring
electrical resistance of the blood sample. Two standard
solutions are used to calibrate the hematocrit sensor and to
obtain the slope. The analyzer then measures the electrical
resistance of the blood sample to obtain the hematocrit
value. The hematocrit value obtained is corrected for the
concentration of the sodium ion.