Masimo Rad-87, Operator'S Manual

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1-6 Rad-87 Pulse CO-Oximeter Operator’s Manual
o v e r v i e w
1
PRINCIPLE OF OPERATION - (CONTINUED)
Once the Rad-87 receives the signal from the sensor, it utilizes Masimo Rainbow SET
signal extraction technology to calculate the patient’s functional arterial oxygen satura-
tion, blood levels of carboxyhemoglobin (SpCO), methemoglobin (SpMet) and pulse rate.
The SpCO and SpMet measurements rely on a multiwavelength calibration equation to
quantify the percentage of carbon monoxide and methemoglobin in arterial blood. In an
ambient temperature of 35º C the maximum skin surface temperature has been measured
at less than 106º F (41º C), verifi ed by Masimo sensor skin temperature test procedure.
FUNCTIONAL SATURATION
The Rad-87 is calibrated to measure and display functional saturation (SpO
2
): the
amount of oxyhemoglobin expressed as a percentage of the hemoglobin that is available
to transport oxygen. Note that carboxyhemoglobin and methemoglobin are not capable
of transporting oxygen, but is recognized as oxygenated hemoglobin by conventional
pulse oximetry.
RAD-87 vs. DRAWN WHOLE BLOOD MEASUREMENTS
When SpO2, SpCO and SpMet measurements obtained from the Rad-87 (noninvasive) are
compared to drawn whole blood (invasive) measurements by blood gas and/or laboratory CO-
Oximetry methods, caution should be taken when evaluating and interpreting the results. The
blood gas and/or laboratory CO-Oximetry measurements may differ from the SpO2, SpCO,
and SpMet measurements of the Rad-87 Pulse CO-Oximeter. In the case of SpO2, different
results are usually obtained from the arterial blood gas sample if the calculated measurement
is not appropriately corrected for the effects of variables that shift the relationship between
the partial pressure of oxygen (PO2) and saturation, such as: pH, temperature, the partial
pressure of carbon dioxide (PCO2), 2,3-DPG, and fetal hemoglobin. In the case of SpCO,
different results are also expected if concentration of methemoglobin in the blood gas sample
is abnormal (greater than 2% for methemoglobin concentration). High levels of bilirubin may
cause erroneous SpO2, SpMet, and SpCO readings. As blood samples are usually taken over
a period of 20 seconds (the time it takes to draw the blood) a meaningful comparison can only
be achieved if the oxygen saturation, carboxyhemoglobin and methemoglobin concentration
of the patient are stable and not changing over the period of time that the blood gas sample is
taken. Subsequently, blood gas and laboratory CO-Oximetry measurements of SpO2, SpCO
and SpMet may vary with the rapid administration of fl uids and in procedures such as dialysis.
Additionally, drawn, whole-blood testing can be affected by sample handling methods and time
elapsed between blood draw and sample testing.
MASIMO SIGNAL EXTRACTION TECHNOLOGY (SET) FOR SpO
2
MEASUREMENTS
Masimo Signal Extraction Technology’s signal processing differs from that of conven-
tional pulse oximeters. Conventional pulse oximeters assume that arterial blood is the
only blood moving (pulsating) in the measurement site. During patient motion, however,
the non-arterial blood also moves, causing conventional pulse oximeters to read low val-
ues, because they cannot distinguish between the arterial and venous blood movement
(sometimes referred to as noise). Masimo SET pulse oximetry utilizes parallel engines
and adaptive digital fi ltering. Adaptive fi lters are powerful because they are able to adapt
to the varying physiologic signals and/or noise and separate them by looking at the whole
signal and breaking it down to its fundamental components. The Masimo SET signal
processing algorithm, Discrete Saturation Transform
®
(DST
®
) reliably identifi es the noise,
isolates it and, using adaptive fi lters, cancels it. It then reports the true arterial oxygen
saturation for display on the monitor.