Operator's Manual

Radical-7 Chapter 1: Technology Overview
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CaO
2
= 1.34 (ml O
2
/g) x Hb (g/dL) x HbO
2
+ PaO
2
(mmHg) x 0.003 (ml
O
2
/dL/mmHg)
Where HbO
2
is the fractional arterial oxygen saturation and PaO
2
is the
partial pressure of arterial oxygen.
For typical PaO
2
values, the second part of the above equation is
approximately 0.3 ml O
2
/dL based on PaO
2
being approximately 100
mmHg. Furthermore, for typical carboxyhemoglobin and methemoglobin
levels, the functional saturation (SpO
2
) as measured by a pulse oximeter
is given by:
SpO
2
= 1.02 x HbO
2
When calculating oxygen content (SpOC), the Radical-7 will use SpfO
2
™ if
available instead of SpO
2
. SpfO
2
is the measured fractional arterial
oxygen saturation.
*Martin, Laurence. All You Really Need to Know to Interpret Arterial Blood
Gases, Second Edition. New York: Lippincott Williams & Wilkins, 1999.
General Description for SpOC
The above approximations result in the following reduced equation for
oxygen content via the Pulse CO-Oximeter:
SpOC (ml/dL*) = 1.31 (ml O
2
/g) x SpHb (g/dL) x SpO
2
+ 0.3 (ml O
2
/dL)
*When ml O
2
/g Hb is multiplied by g/dL of SpHb, the gram unit in the
denominator of ml/g cancels the gram unit in the numerator of g/dL
resulting in ml/dL (ml of oxygen in one dL of blood) as the unit of
measure for SpOC. See
Warnings and Cautions on page 15.