Covidien Nellcor GR101704-RR, Operator'S Manual

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Additional Nellcor™ Pulse Oximetry Sensor
Operator’s Manual Addendum ADD-25
1.8
Additional Nellcor™ Pulse Oximetry Sensor
When selecting a Nellcor™ sensor, consider the patient’s weight and activity
level, the adequacy of perfusion, and the available sensor sites, the need for
sterility, and the anticipated duration of monitoring. Use the recommended
sensor’s
Instructions for Use to guide sensor selection or contact Covidien or a
local Covidien representative. Reference Nellcor™ Sensor Performance Consid-
erations , p. ADD-22.
1.9
Theory of Operations
The Respiration Rate parameter, when used in conjunction with the
Nellcor™ Bedside Respiratory Patient Monitoring System and Nellcor™ Adult
Respiratory Sensor, provides continuous non-invasive monitoring of arterial
oxygen saturation, pulse rate and respiration rate using a single sensor. The
Respiration Rate parameter provides an indication of central ventilatory drive
by processing and interpreting the photoplethysmogram, or pleth.
The pleth signal is used to measure arterial oxygen saturation (SpO
2
). A typical
pleth pattern includes a regular cardiac 'pulse' waveform on top of a large con-
stant baseline component, or DC component. See
Figure 1-17 (a).
In clinical settings, both the cardiac pulse and baseline components may vary
over time due to physiologic conditions and changes. In standard pulse oxim-
etry, these variations are typically filtered out in order to accurately measure
arterial oxygen saturation (SpO
2
). These same subtle variations, however, may
be used to derive respiration rate by tracking three types of changes associated
with the respiratory cycle.
1.
Baseline (DC) variation — Changes in intrathoracic pressure during the respira-
tory cycle influence venous return to the heart and result in baseline DC variation
in the pleth. Reference
Figure 1-17 (b).
2.
Pulse amplitude variation — Changes in intrathoracic pressure during inspira-
tion also lead to variation in cardiac stroke volume and result in pulse amplitude
variations. Reference
Figure 1-17 (c).
Table 1-5. Additional Sensor Model and Patient Size
Nellcor™ Pulse Oximetry Sensor SKU Patient
Size
Nellcor™ Adult Respiratory Sensor (Sterile, single-use only) 10068119 >30 kg