RADIOMETER FLEX ABL90, Reference Manual

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ABL90 FLEX reference manual 8. Parameters
8-39
The actual position of the ODC at 37  C for a given sample is, in principle,
determined in two steps:
1. The calculation of the combined effect on the ODC position at 37  C of all
known causes for displacement (= ac in equation 46.13), and based on
this position.
2. The computation by a numerical method of the actual position of the
ODC curve by shifting it to pass through the known set of coordinates
(P
0
, S
0
).
Eq. Description
46.13 a = ac + a6
46.14 ac = a1 + a2 + a3 + a4 + a5
46.15 a1 =  0.88  (pH  7.40)
46.16
2
CO
a2 0.048 ln
5.33
p
 
46.17 a3 0.7 MetHb F   
46.18
   
a4 0.06 0.02 HbF DPG 5 F c    
46.19 a5 0.25 HbF F   
Step Description
I: pO
2
, sO
2
can be used.
If sO
2
> 0.97, the calculation is based on II or III – see
below.
Coordinates (P
0
, S
0
) are calculated from equations
(46.9) and (46.11).
If FCOHb and FMetHb are not known, the default values
are used.
The ODC is shifted from the reference position to a
position that corresponds to the effect of all measured
parameters according to step I.
The magnitude of the shift is "ac".
The ODC is then further shifted to pass through the
point (P
0
, S
0
).
The magnitude of the shift is "a6".
The actual ODC
position
Determining
the actual
displacement