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
pH 15 0.98 0.12 0.99996 0.00397 6.715 – 7.768
In the comparison study, samples were analyzed in parallel on the i15 Blood Gas and Chemistry
Analysis System and the Rapidpoint 400 system. Two replicates of each sample were analyzed
on each system.
Parameter N Slope Intercept
Correlation
Coefficient
Sy.x Range
pH 215 1.0259 -0.1934 0.9919 0.0126 7.137 – 7.720
12.1.5 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 pH
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 pH measurement.
12.2 pCO
2
pCO
2
, the partial pressure of carbon dioxide, is measured by potentiometry. pCO
2
is determined
by the measured potential through the Nernst equation.
If test results are inconsistent with the clinical assessment, the sample should be analyzed again
with a new test cartridge.
12.2.1 Intended Use
The pCO
2
test is intended for the quantification of pCO
2
in arterial, venous, or capillary whole
blood samples.