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Radical-7R Pulse CO-Oximeter Operator’s Manual
4
O p e r a t i o n
NUMERIC DISPLAY - SpO
2
Stability of the SpO2 readings may be a good indicator of signal validity. Although stability is a relative term,
experience will provide confidence in changes that are artifactual or physiological and the speed, timing, and
behavior of each. The stability of the readings over time is affected by the averaging mode being used. The
longer the averaging time, the more stable the readings tend to become. This is due to a dampened response
as the signal is averaged over a longer period of time than during shorter averaging times. However, longer
averaging times delay the response of the Pulse CO-Oximeter and reduce the measured variations of SpO2
and pulse rate. Inaccurate measurements may be caused by:
■
Elevated levels of Carboxyhemoglobin.
■
Elevated levels of Methemoglobin.
■
Severe anemia.
■
Elevated Total Bilirubin levels.
■
Low arterial perfusion.
■
Motion artifact.
NUMERIC DISPLAY - PULSE RATE
The Pulse Rate displayed on the Radical-7R Pulse CO-Oximeter may differ slightly from the heart rate
displayed on ECG monitors due to differences in averaging times. There may also be a discrepancy
between cardiac electrical activity and peripheral arterial pulsation. Significant differences may indicate
a problem with the signal quality due to physiological changes in the patient or one of the
instruments or
application of the sensor or patient cable. The pulsations from intra-aortic balloon support can cause the
pulse rate displayed on the Pulse CO-Oximeter to be significantly different than the ECG heart rate.
NUMERIC DISPLAY - RRa
Rainbow Acoustic Monitoring continuously measures a patient’s respiration rate based on air-
flow sounds generated in the upper airway. Inaccurate measurements may be caused by:
■
Excessive ambient or environmental noise.
■
Improper sensor placement.
NUMERIC DISPLAY - SpCO
A stable SpCO reading is associated with correct sensor placement, small physiological
changes during the measurement and acceptable levels of arterial perfusion in the patient’s
fingertip (measurement site). Physiological changes at the measurement site are mainly
caused by fluctuations in the oxygen saturation, blood concentration and perfusion. Inaccurate
measurements may be caused by:
■
Levels of methemoglobin approximately 1.5% or above.
■
Intravascular dyes such as indocyanine green or methylene blue.
■
Abnormal hemoglobin levels.
■
Low arterial perfusion.
■
Low arterial oxygen saturation levels.
■
Elevated Total Bilirubin levels.
■
Motion
artifact.
NUMERIC DISPLAY - SpMet
A stable SpMet reading is associated with correct sensor placement, small physiological
changes during the measurement and acceptable levels of arterial perfusion in the patient’s
fingertip (measurement site). Physiological changes at the measurement site are mainly
