RADIOMETER ABL800 FLEX - Page 158

ABL800 FLEX Reference Manual 6. Parameters
Derived parameters, Continued
Oxygen derived
parameters
(continued)
Symbol Definition Type Eq.
FShunt Relative physiological shunt or concentration-
based shunt [5,8,9].
• Calculated from the pulmonary shunt
equation:
&
&
()
Q
Q
tO (a v)
tO A tO (a)
s
t
2
22
=
+
−
−
1
1
c
cc
if both arterial and mixed venous blood
samples are used.
• May be estimated from one arterial sample
by assuming a constant difference in the
concentrations of total oxygen in arterial
and mixed venous blood:
ctO (a v) 2.3 mmol / L (5.1 mL / dL)
2
−
=
dv
34
FShunt (T) FShunt at patient temperature. dv
35
RI Respiratory Index; ratio between the oxygen
tension difference of alveolar air and arterial
blood and the oxygen tension of arterial blood.
dv
36
RI(T) Respiratory Index; ratio between the oxygen
tension difference of alveolar air and arterial
blood and the oxygen tension of arterial blood at
patient temperature.
dv
37
VO
2
/V(dry
air)
Volume fraction of oxygen in dry air. dv
52
Q
x
Cardiac oxygen compensation factor of arterial
blood defined as the factor by which the cardiac
output should increase to allow release of 2.3
mmol/L (5.1 mL/dL) oxygen at a mixed venous
pO
2
of 5.0 kPa (38 mmHg) [5,8].
dv
38
V(B) Volume of blood, calculated when FCOHb and
V(CO) values are keyed in [5].
dv
42
6-21