OPTi CCA-TS2, Руководство оператора, Страница: 210 / 299

Operator’s Manual – OPTI CCA-TS2 PO2-1
ANALYTES P O
2
PO
2
Clinical Significance
1
The
P
O
2
value of arterial blood is used to assess how well the body is able to absorb oxygen in the lungs.
Values below the normal arterial P O
2
( arterial hypoxemia ) are usually caused by pulmonary, circulatory,
or respiratory abnormalities (e.g. bronchial obstruction, vascular problems, decrease in cardiac output,
increased oxygen demand, anatomical heart defect, low inspired O
2
content). Generally, O
2
levels
above 100 mmHg do not contribute significantly to the oxygen content since, with normal hemoglobin
concentrations, 80 - 100 mmHg,
P
O
2
provides a 97% saturation level, and a level greater than 100%
cannot be achieved.
Measurement Principle
The P O
2
optode measurement principle is based upon luminescence quenching, first documented in the
1930’s 2
,
and commercially utilized to measure blood P O
2
in 1983 3
.
The relationship of luminescence to
P O
2
is quantified by the Stern-Volmer equation,
I
0
/ I = 1 + kP
which describes how the fluorescence emission intensity “I” is reduced as the P O
2
“P”, is increased.
Unlike conventional electrochemical “Clark”
P
O
2
electrodes, the oxygen optode does not consume
oxygen molecules during the measurement.
The P O
2
partial pressure is influenced by the local barometric pressure, as dictated by Dalton’s law.
The OPTI CCA-TS2 incorporates a pressure transducer, which accurately tracks the local barometric
pressure and automatically compensates for it. The OPTI CCA-TS2 has been factory-calibrated to the
absolute barometric pressure.
Measurement Range
Range Resolution (Low/High) Units
10 to 700 1/0.1 mmHg
1.33 to 93.31 0.1/0.01 kPa
Standard Reference Cassette (SRC) Limit Values
LOW NORMAL HIGH Units
60.0 ± 3.0 100.0 ± 3.0 170.0 ± 3.0 mmHg
8.00 ± 0.40 13.33 ± 0.40 22.66 ± 0.40 kPa
Interferences
Interference testing was done on the OPTI CCA platform, with a standard OPTI style pO
2
sensor.
No changes were made to the sensor or the measurement principle, so the interference of the OPTI CCA-
TS2 is equivalent to the OPTI CCA.
Only clear, uncolored quality control materials, such as OPTI CHECK or OPTI CHECK PLUS brand
aqueous controls should be used with the OPTI CCA-TS2 system. Colored materials, including
proficiency testing materials, may interfere with the pO
2
measurement, or fail to be properly aspirated.