OPTi CCA-TS2 - Page 265

Operator’s Manual – OPTI CCA-TS2 THB/SO2-3
ANALYTES tHb/SO
2
Interferences
The following exogenous interferents were quantied in tonometered whole blood, showing interferences
to dyes which typically have short half-lives within the body before being metabolized by the liver.
This testing was done on the OPTI CCA platform, with a standard OPTI style cassette. No changes were
made to the sensor or the measurement principle for the tHb and SO
2
measurement, so the interference of
the OPTI CCA-TS2 is equivalent to the OPTI CCA.
EXOGENOUS
Substance Amount tHb change (g/dL) SO
2
change (%)
Cardio (indocyanine) green 0.5 mg/dL +4.7 +4%
Evan’s Blue 5.0mg/dL <1.0 -17%
Methylene blue 25 mg/dL +3.0 -37%
ENDOGENOUS
Substance Amount tHb change (g/dL) SO
2
change (%)
Carboxyhemoglobin 10% -2.0 <2%
Carboxyhemoglobin 20% -3.3 <2%
Methemoglobin 13% +1.7 -7%
Rapidly sedimenting blood samples should be mixed thoroughly and immediately aspirated into the
OPTI cassette, as described in Section 5.1.7 “Handling and Storage of Samples”, to ensure accurate tHb
measurements. If allowed to sediment, the blood sample’s reported tHb may be falsely high or low.
Fetal hemoglobin taken from cord blood extracts was tested and showed no interference to the tHb and
SO
2
measurement.
Only clear, uncolored quality control materials, such as OPTI CHECK or OPTI CHECK PLUS brand
aqueous controls should be used with the OPTI CCA-TS2 system. Colored materials, including
prociency testing materials, may interfere with the tHb and SO
2
measurement, or fail to be properly
aspirated.