GE MAC 5000 Operator's Manual page 25

Recording ECGs During Defibrillation
This equipment is protected against the effects of cardiac
defibrillator discharge to ensure recovery, as required by
test standards.
The patient signal input of the acquisition module is
defibrillation-proof. Therefore, it is not necessary to remove
the ECG electrodes prior to defibrillation.
When using stainless steel or silver electrodes a
defibrillator discharge current may cause the electrodes to
retain a residual charge causing a polarization or dc offset
voltage. This electrode polarization will block acquisition of
the ECG signal. To avoid this condition, use non-polarizing
electrodes (which will not form a dc offset voltage when
subjected to a dc current) such as silver/silver-chloride
types if there is a situation where there is a likelihood that
a defibrillation procedure will be necessary.
If polarizing electrodes are used, we recommend
disconnecting the leadwires from the patient before
delivering the shock.
MAC 5000 System — 2000657-057, Revision B
Electrode defibrillation recovery is the ability of the
electrode to allow the ECG trace to return after
defibrillation. We recommend using non-polarizing
disposable electrodes with defibrillation recovery ratings as
specified in AAMI EC12 3.2.2.4. (MMS P/N 9623-105 Silver
MacTrodes, MMS spec. TP9623-003). AAMI EC12 requires
that the polarization potential of an electrode pair does not
exceed 100mV, 5 seconds after a defibrillation discharge.
Accuracy of the Input Signal Reproduction
Overall System Error is tested using the method
described in AAMI EC11 3.2.7.1. Overall System Error
is +5%.
Frequency Response is tested using the method
described in AAMI EC11 3.2.7.2 methods A and D.
Introduction: Safety Information
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