Mindray Passport 5-Lead, Service Manual

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Operation (XG) Operation (5-Lead, 5L, LT and XG)
1 - 132 0070-00-0420 Passport 5-Lead, 5L, LT, XG Service Manual
2. This mode uses a 2 to 3 second averaging time and therefore is more affected by
patient motion. It is useful for special applications that require a fast response time, such
as sleep studies.
3. This mode uses a 10 to 15 second averaging time and consequently is least affected by
patient motion. In this mode, if SpO
2
has been selected as the source for pule rate
information, pulse rate is not displayed and there is no pulse tone.
Pleth Auto Scaling
The Pleth waveform is automatically scaled when using Nellcor® SpO
2
. There is no
adjustment that can be made to the pleth waveform size.
Changing Operating Modes
To change from 1 to 2 or 3, select SpO
2
in the menu and toggle through the choices of 1, 2,
and 3 using the up and down arrow keys. Press SELECT (2) then EXIT (3) to lock the choice in
and return to monitoring mode. See “Use of Menus” on page 1-109 for details on using
menus.
The operating mode will be displayed in the pleth waveform window.
1.6.11 Respiration Monitoring
The Passport XG Monitor offers two kinds of respiratory monitoring: thoracic impedance and
CO
2
waveform. Both methods offer certain benefits and limitations. A respiration source must
be selected, see “Resp Menu” on page 1-179.
WARNING: Thoracic respiration measurement may interfere with some
pacemakers. Refer to the pacemaker’s manual.
1.6.11.1 Thoracic Impedance
The Passport XG Monitor presents a small electrical signal across the RA and LA ECG limb
leads. This signal changes as the patient’s chest wall rises and falls during the breath cycle.
The advantage of the thoracic impedance method is that respiration is obtained non-
invasively and without any extra cost. It is important to use cables with internal resistors for
Thoracic Impedance, see Section 5 in the Datascope P/N’s 0070-00-0397, 0070-00-0440,
0070-00-0503 Passport Operating Instructions for a list of cables.
Choke blocks are electrical filters that may be used in electro-cautery environments where
ECG interference can be substantial. These filters remove the electro-cautery noise, but also
block the signal used by the Passport XG Monitor to measure respiration.
The filling and emptying of the heart chambers can interfere with the thoracic impedance
signal, so called cardiovascular artifact (CVA), such that the respiratory signal matches the
heart rate. The Passport XG warns the operator when the respiration value equals the heart
rate by displaying the CVA message.
If the patient’s airway is obstructed and the patient attempts to breath, then the chest wall can
move and create a respiratory signal even though no gas flow is occurring to the patient.