User's Manual

i15 Blood Gas and Chemistry Analysis System User Manual Parameters
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pCO
2
is an important indicator to reflect respiratory acid-base balance. If pCO
2
is above the
normal range, it is termed respiratory acidosis. If pCO
2
is below the normal range, it is termed
respiratory alkalosis. Metabolic factors can also cause pCO
2
increase/decrease: metabolic
acidosis leads to decreased pCO
2
, and metabolic alkalosis leads to increased pCO
2
. pCO
2
along
with pH is a more persuasive tool to assess acid-base balance.
12.2.2 Traceability
pCO
2
values assigned to calibrant and controls are traceable to NIST standards.
12.2.3 Temperature Correction
pCO
2
is a temperature dependent quantity which is measured at 37°C on the system. The pCO
2
value can be corrected to the patient’s temperature other than 37°C. Patient temperature can be
entered on the Enter Patient Information screen during each patient sample test.
The pCO
2
at the patient’s temperature is calculated as follows:
pCO
2
(T) = pCO
2
× 10
0.019(T - 37)
12.2.4 Performance Characteristics
Experiments are designed according to the following CLSI guidelines: CLSI EP6-A for linearity
studies, CLSI EP9-A2 for method comparison studies, and CLSI EP7-A2 for interference studies.
Typical performance data presented below were obtained by technologists, nurses, physicians and
therapists trained in the use of the system and the comparative method.
Repeatability on RNA Medical
®
QC823 Blood Gas●Electrolyte●Metabolite●BUN controls was
estimated using one lot of test cartridges, and 20 replicates of each level were successively analyzed
on one i15 Blood Gas and Chemistry Analysis System. RNA Medical
®
QC823 Blood
Gas●Electrolyte●Metabolite●BUN controls are traceable to NIST standards.
In the following repeatability data table below,
SD refers to the standard deviation.
Controls Mean
SD
Level 1
68.63 2.650
Level 2
43.97 1.368
Level 3
24.41 1.910
Precision and recovery on whole blood samples was estimated using multiple whole blood