ABL90 FLEX reference manual 8. Parameters
8-31
Eq. 34 [5]:
22
22
tO (c) tO (a)
Shunt=
tO (c) tO (v)
cc
F
cc
and
Eq. Description
34.1
22
22
tO (A) tO (a)
Shunt
tO (A) tO (v)
cc
F
cc
34.2
1
22
22
tO (a) tO (v)
Shunt= 1
tO (A) tO (a)
cc
F
cc
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
22 2
tO (a) 0.0105 O (a) tHb 1 COHb MetHb O (a)cpcFFs
34.4
22
2
tO (A) 0.0105 O (A) tHb
1COHbMetHb O(A)
cpc
FF s
34.5
22
2
tO (v) 0.0105 O (v) tHb
1COHbMetHb O(v)
cpc
FF 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