Roche Diagnostics
Instructions for Use · Version 13.0 93
cobas b 123 POC system 4 Theoretical foundations
Table of contents
Theoretical foundations 4
This chapter contains background information on how calculated values are derived
and how calibrations are performed on the system. In addition, unit conversion
tables, standard values and reference ranges for measured parameters are provided.
In this chapter
Chapter
4
Assigning unit formats to parameters ...............................................................................95
Selecting between pH and H
+
unit formats......................................................................96
Parameters and calculations ...............................................................................................97
Conversion table for units.............................................................................................97
Temperature..............................................................................................................97
Standard values and ranges...........................................................................................97
Equations.........................................................................................................................98
cH
+
.............................................................................................................................98
cHCO
3
-
......................................................................................................................98
ctCO
2
(P) ...................................................................................................................98
FO
2
Hb .......................................................................................................................98
BE...............................................................................................................................99
BE
ecf
...........................................................................................................................99
BB...............................................................................................................................99
SO
2
.............................................................................................................................99
SO
2
(c) ........................................................................................................................99
P
50
........................................................................................................................... 100
ctO
2
......................................................................................................................... 101
ctCO
2
(B) ................................................................................................................ 101
pH
st
......................................................................................................................... 101
cHCO
3
-
st
................................................................................................................ 102
PAO
2
....................................................................................................................... 102
AaDO
2
.................................................................................................................... 102
a/AO
2
...................................................................................................................... 103
avDO
2
..................................................................................................................... 103
RI............................................................................................................................. 103
Shunt (Qs/Qt)........................................................................................................ 104
Shunt estimated (Qs/Qt
est
).................................................................................. 105
nCa
2+
...................................................................................................................... 105