OPTi CCA-TS2, Руководство оператора, Страница: 215 / 299

Operator’s Manual – OPTI CCA-TS2 PO2-B-1
ANALYTES P O
2
(Dry Sensor)
PO
2
(Dry Sensor - B-Lac Cassette)
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