Rapidlab 1200 Operator’s Guide: System Overview and Intended Use 1-57
02087462 Rev. V
If FO
2
Hb is unavailable, oxygen content is derived from estimated oxygen
saturation [O
2
SAT(est)] according to the following equation:
O
2
CT = (1.39 × ctHb × O
2
SAT(est)/100)+ (0.00314 × pO
2
)
If ctHb is not measured or entered, O
2
CT is not displayed or printed.
NOTE: Clinically significant errors can result from incorporating an estimated
value for oxygen saturation in further calculations, such as oxygen content and
shunt fraction (Q
sp
/Q
t
), or by assuming that the value obtained [O
2
SAT(est)] is
equivalent to fractional oxyhemoglobin.
19
Oxygen Content of Hemoglobin
The oxygen content of hemoglobin, ctO
2
(Hb), is the volume of oxygen actually
bound to hemoglobin.
19
The oxygen content of hemoglobin, with hemoglobin
oxygen saturation and oxygen capacity, is a useful parameter for determining the
amount of oxygen in the blood that is actually available to the tissues and for
determining the effectiveness of oxygen therapy.
The oxygen content of hemoglobin for a sample when pO
2
is not available is
determined using the following equation:
ctO
2
(Hb) = (OBF × tHb × FO
2
Hb)
where OBF is the O
2
binding factor. The system uses the default value of 1.39, or
whatever value is entered as the default value in Setup. FO
2
Hb is in decimal
format.
Oxygen Capacity of Hemoglobin
The oxygen capacity of hemoglobin (BO
2
) is the maximum amount of oxygen
that the hemoglobin in a given quantity of blood can carry. This value represents
the potential of hemoglobin to bind to oxygen and includes all the oxygen that can
be bound to the available hemoglobin.
19
The oxygen capacity of hemoglobin,
with hemoglobin oxygen saturation and oxygen content, is a useful parameter for
determining the amount of oxygen in the blood that is actually available to the
tissues and for determining the effectiveness of oxygen therapy.
The oxygen capacity of hemoglobin is determined using the following equation:
BO
2
= OBF x tHb x (FO
2
Hb + FHHb)
where OBF is the O
2
binding factor. The system uses the default value of 1.39, or
whatever value is entered as the default value in Setup. FO
2
Hb + FHHb are in
decimal format.