DATREND Systems Oxitest Plus 7, Руководство по эксплуатации

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OXITEST PLUS 7 OPERATING MANUAL
When using Oxitest Plus 7 , the primary consideration is to first choose the correct make, model
and sensor type for the device under test. Many manufacturers of oximeters use another company’s
technology, for instance, Tyco provides Nellcor technology on an OEM basis to a large number of
physiological monitor manufacturers. Each of these individual manufacturers may use the R-Curve
developed by Nellcor, or they may decide to develop their own curve. In addition, they may use the
Nellcor sensors, or manufacture a sensor under their own brand name. These same manufacturers
may use both Nellcor sensors and their own, implementing a different R-Curve for each sensor.
With all of these combinations possible, it is very important to select the correct pulse oximeter and
sensor type in the menu to ensure that the simulation is correct for the unit under test.
Disposable sensors can produce questionable results when used with ‘compatible’ oximeters. For
instance, Nellcor makes a disposable finger sensor which, due to the cable connector, can be
attached to many other manufacturer’s oximeters. In order to have a better manufacturing yield,
Nellcor ‘codes’ the disposable sensor with a resistor, which the Nellcor oximeter uses to adjust the
R-Curve for the sensor. In effect, this is providing compensation for the optical response of the
sensor. However, even though the Nellcor disposable sensor fits on other manufacturer’s cables, it
may not provide reliable results - especially at the lower saturation levels - if the R-Curve variation is
not taken into account.
5.1.2 Probe/Sensor Interface
The single most variable parameter in testing oximeters is the fit between the tester probe and the
oximeter sensor. Due to the wide variety of sensor shapes, a test probe which provides an excellent
fit with a Nellcor sensor may not be as good a fit to a Nonin sensor. The
Oxitest Plus 7 probe has
been designed to provide the best-compromise fit for testing both disposable and nondisposable
sensors across many brands.
Most non disposable sensors fit into two categories of design: 1) Nellcor style - with an ‘end stop’ for
the finger or 2) Ohmeda style - with a ‘finger depression’ molded in the sensor. In many cases, the
sensor can be simply slid over the test probe and will sit ‘naturally’ in place. If you do not get good
results with this method, the following instructions should improve the results:
1) Nellcor (Tyco) Style
The Nellcor style sensor generally utilizes a soft, cushiony material to surround the finger, with a
hard plastic or metal outer shell. Inside there is an ‘end stop’ to prevent the finger from going
too far into the sensor. Examples of this type include Nellcor, Nonin, and
SpaceLabs/Novametrix finger clip sensors. The ‘end stop’ of the Nellcor DS-100A finger clip
sensor can be seen in
Figure 6 .
Test Useage/Chapter 5
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