6. Parameters ABL800 FLEX Reference Manual
General information, Continued
Derived parameters are calculated according to the equations stated.
Derived
parameters
If… Then…
the required measured or input
values are unknown
default values are used, unless a measured
parameter does not have a value or is outside
the measuring range.
all values are known the derived parameter is designated calculated
and a ‘c’ is added to the result.
a default value is used the derived parameter is designated estimated
and an ‘e’ is added to the result.
If one or more default values have been used in the calculation, the result may
deviate significantly from the true value. The deviation on “estimated” oxygen status
parameters may become particularly significant if default values are used instead of
measured blood oximetry data.
In some cases however, the default value is not accepted as the input for the
calculation. This is because the actual values of the missing parameter may deviate
significantly from the default value, thus making the estimation clinically
inappropriate. If sO
2
cannot be measured due to severe errors, it will be calculated.
Measured
parameters
Some of the listed parameters are measured, depending on the analyzer
configuration. In these cases the equation given only applies if that parameter is
not directly measured by the analyzer.
Sample type
Unless otherwise stated, a parameter will be calculated or estimated irrespective of
the choice on the Patient Identification screen: ‘Arterial’, ‘Capillary’, ‘Venous’,
‘Mixed venous’, or ‘Not specified’. Some parameters however are defined for
arterial samples only; they will be calculated only for sample types entered as
‘Arterial’ or ‘Capillary’.
The symbol for system (blood (B) or plasma (P)) is not stated in the equations
unless it is important for the calculation.
The units given for each parameter refer to the units available on the analyzer for that
parameter.
Units
Default values
The default values are listed in Default Values at the end of this chapter.
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