RADIOMETER FLEX ABL90, Reference Manual

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ABL90 FLEX reference manual 8. Parameters
8-31
Eq. 34 [5]:
2 2
2 2
tO (c) tO (a)
Shunt=
tO (c) tO (v)
c c
F
c c


and
Eq. Description
34.1
2 2
2 2
tO (A) tO (a)
Shunt
tO (A) tO (v)
c c
F
c c



34.2
1
2 2
2 2
tO (a) tO (v)
Shunt= 1
tO (A) tO (a)
c c
F
c c

 


 

 
where
ctO
2
(c): total oxygen in pulmonary capillary blood
ctO
2
(a): total oxygen in arterial blood
ctO
2
(A): total oxygen in alveolar air. Oxygen tension = pO
2
(A).
ctO
2
(v– ): total oxygen in mixed venous blood
34.3
 
2 2 2
tO (a) 0.0105 O (a) tHb 1 COHb MetHb O (a) c p c F F s      
34.4
 
2 2
2
tO (A) 0.0105 O (A) tHb
1 COHb MetHb O (A)
c p c
F F s
  
  
34.5
 
2 2
2
tO (v) 0.0105 O (v) tHb
1 COHb MetHb O (v)
c p c
F F s
  
  
where:
pO
2
(a): oxygen tension in arterial blood; measured
pO
2
(A): oxygen tension in alveolar blood. See equation 15.
pO
2
(v– ): oxygen tension in mixed venous blood; measured and then
entered
sO
2
(a): oxygen saturation in arterial blood; can be measured
sO
2
(A): oxygen saturation in (alveolar) blood calculated from equation
39 where P = pO
2
(A)
sO
2
(v– ): oxygen saturation in mixed venous blood; measured and then
entered
The calculation requires entering the sample type as "Arterial" or
"Capillary"
If sO
2
(a) > 0.97, the default value (3.578 kPa) will be used to estimate
the ODC.
If no venous sample is measured, FShunt is estimated assuming:
ctO
2
(a) – ctO
2
(v– ) = 2.3 mmol/L in equation 34.2
FShunt