User's Manual

i15 Blood Gas and Chemistry Analysis System User Manual Parameters
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Parameter N Slope Intercept
Correlation
Coefficient
Sy.x Range
pO
2
215 0.9811 1.3173 0.9986 2.0303 20.4 – 191.0
12.3.5 Interfering Substances
Aqueous sample was spiked by addition of a potentially interfering substance to the following
test concentration to test for interferences. Twelve replicates of both the spiked sample and the
unspiked sample were tested on two i15 Blood Gas and Chemistry Analysis Systems with one lot
of test cartridges. The interference was computed using the difference between the mean of the
spiked sample and the unspiked sample.
The following substances were tested and found not to be clinically significant for the pO
2
measurement: 24mmol/L hydroxyurea, 1.0mmol/L magnesium, 20mmol/L lactate, 4.00mmol/L
salicyte, 37.5mmol/L bromide, and 20mmol/L β-hydroxybutyrate.
NOTE:
It is possible that there are other substances interfering with the pO
2
measurement.
12.4 Sodium (Na
+
)
Sodium is measured by potentiometry with an ion-selective electrode. The concentration of
sodium ions is determined by the measured potential through the Nernst equation. The system
uses a direct (undiluted) method to measure sodium and the obtained values may differ from
those obtained by an indirect (diluted) method.
If test results are inconsistent with the clinical assessment, the sample should be analyzed again
with a new test cartridge.
12.4.1 Intended Use
The sodium test is intended for the quantification of sodium in arterial, venous, or capillary whole
blood samples.
Sodium is the major cation in the extracellular space in the body. It plays an important part in
maintaining osmotic pressure and acid-base balance.
Monitoring blood sodium level is important in the diagnosis or monitoring of diseases involving
electrolyte imbalance and all disturbances of the water balance, heart and kidney insufficiencies,