Nellcor OXIMAX N-560, Operator'S Manual

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Principles of Operation
94
Functional Testers and Patient Simulators
Some models of commercially available bench top functional testers and
patient simulators can be used to verify the proper functionality of Nellcor
pulse oximeter sensors, cables and monitors. See the individual testing
device’s operator’s manual for the procedures specific to the model of
tester being used.
While such devices may be useful for verifying that the pulse oximeter
sensor, cabling, and monitor are performing as designed, they are
incapable of providing the data required to properly evaluate the accuracy
of a system’s SpO
2
measurements. Fully evaluating the accuracy of the
SpO
2
measurements requires, at a minimum, accommodating the
wavelength characteristics of the sensor and reproducing the complex
optical interaction of the sensor and the patient’s tissue. These capabilities
are beyond the scope of known bench top testers. SpO
2
measurement
accuracy can only be evaluated in vivo by comparing pulse oximeter
readings with values traceable to SaO
2
measurements obtained from
simultaneously sampled arterial blood made using a laboratory
CO-oximeter.
Many functional testers and patient simulators have been designed to
interface with the pulse oximeter’s expected calibration curves and may
be suitable for use with Nellcor monitors and/or sensors. Not all such
devices, however, are adapted for use with the Nellcor
O
XI
M
AX
digital
calibration system. While this will not affect use of the simulator for
verifying system functionality, displayed SpO
2
measurement values may
differ from the setting of the test device. For a properly functioning
monitor, this difference will be reproducible over time and from monitor
to monitor within the performance specifications of the test device.