Roche cobas b 123 - Equations

Roche Diagnostics
98 Instructions for Use · Version 13.0
4 Theoretical foundations cobas b 123 POC system
Parameters and calculations
Equations
WARNING
If calculated values exceed their critical ranges, verify the validity of your results
with a medical specialist before making any clinical decisions.
q
Default units are used for the calculation of the equations.
q
Calculated values that require measurement results from arterial blood are only provided
for “arterial” and “capillary” blood types.
q
You can find all referenced publications in the bibliography at the end of this section.
cH
+
Hydrogen ion concentration
[1]
Unit: [nmol/L]
Equation 4-3
cHCO
3
-
Bicarbonate concentration in plasma
[1]
Unit: [mmol/L]
Equation 4-4
ctCO
2
(P)
Total concentration of CO
2
in plasma
[1]
Unit: [mmol/L]
Equation 4-5
FO
2
Hb
Fractional oxygen saturation
[1]
Unit: [-]
Equation 4-6
FH
+
= 10
(9-pH)
cHCO
3
-
= 0.0307 * PCO
2
* 10
(pH-6.105)
ctCO
2
(P) = cHCO
3
-
+ (0.0307 * PCO
2
)
FO
2
Hb
O
2
Hb
100
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