RADIOMETER ABL800 FLEX Reference Manual

3. Optical measuring principles ABL800 FLEX Reference Manual
Correcting for interferences, Continued
Most likely
interfering
substances
Fetal hemoglobin and non-hemoglobin substances present in blood that absorb
light within the same wavelength range used to measure the oximetry parameters
and bilirubin, will interfere with the true spectra of the blood samples.
The optical system in the ABL800 FLEX analyzers compensates for the most
likely interfering substances by repressing their spectra.
The interference from following substances the analyzer compensates for when
measuring the oximetry parameters:
Intralipids (turbidity)
Sulfhemoglobin, SHb
Repressing
spectra
Repressing the spectra of the likely interfering substances is done in two ways
depending on the substance:
• Either the substance is taken account of in the calculation of the matrix of
constants, K (see the section
Measuring Principle in this chapter). This applies
to Intralipids and Sulfhemoglobin,
• Or the substance is detected, and the measured spectrum is corrected
accordingly. This applies to HbF.
Residual
spectrum
A measured spectrum is compared to a model spectrum calculated from the
determined concentrations. The difference between the two spectra is then called
the residual spectrum. If the difference is too high a warning (Oxi spectrum
mismatch) is issued on all the oximetry module parameters
ctHb, sO
2
, FO
2
Hb,
FCOHb, FMetHb, FHHb, FHbF and ctBil.
The same action is taken if one of the following conditions exist and
FHb
deriv
is
defined as one of the parameters
sO2, FO
2
Hb, FCOHb, FMetHb, FHHb:
• ctHb<−0.1mmol/L or ctHb>25mmol/L.
• FHb(deriv)<-2% or FHb(deriv)>102%.
• Negative fraction of SHb<−2% is detected.
• Value of Turbidity<−0.5%.
3-8

RADIOMETER ABL800 FLEX Specifications

General

Brand	RADIOMETER
Model	ABL800 FLEX
Category	Measuring Instruments
Language	English