User's Manual

i15 Blood Gas and Chemistry Analysis System User Manual Parameters
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NOTE:
It is possible that there are other substances interfering with the K
+
measurement.
12.6 Ionized Calcium (Ca
++
)
Ionized calcium (Ca
++
) is measured by potentiometry with an ion-selective electrode. The
concentration of ionized calcium 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.
12.6.1 Intended Use
The ionized calcium test is intended for the quantification of ionized calcium in arterial, venous,
or capillary whole blood samples.
Ca
++
, the physiologically active form of calcium, plays an important role in muscle contraction,
transmission of nerve impulses, and cardiac functions.
For patients who are in critical care situations, especially those who need to receive large
amounts of blood, the Ca
++
level should be monitored closely.
12.6.2 Traceability
Ionized calcium concentration values assigned to calibrant and controls are traceable to NIST
standards.
12.6.3 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.