ZOLL X Series, Operator'S Manual

Page: 244 / 344

Chapter 20 See-Thru CPR
20-2 www.zoll.com 9650-001355-01 Rev. M
See-Thru CPR enables the rescuer to see a close approximation of the patient’s underlying ECG
rhythm while performing CPR. See-Thru CPR is available if the X Series is monitoring CPR.
Chest compressions introduce CPR artifact into the ECG signal. See-Thru CPR uses a filter
that relies on the correlation between CPR compressions, as detected by the ZOLL Onestep,
OneStep Complete
or CPR-D-padz, and the CPR artifact to remove much, but not all, of the
artifact from the ECG signal. Under some conditions, residual noise after filtering can obscure
the ECG rhythm, requiring the rescuer to stop CPR to assess the ECG. For example, in the case
of asystole or low amplitude PEA, the residual artifact seen after filtering may look like fine
ventricular fibrillation.
Because the filtered ECG signal may contain residual chest compression and/or filtering
artifacts,
a rescuer should always follow the standard procedure of stopping CPR to assess the
patient’s ECG rhythm before determining treatment .
Using See-Thru CPR
To use See-Thru CPR
•
The X Series unit must be monitoring CPR.
•
ZOLL OneStep CPR pads, OneStep Complete pads, or CPR-D-padz must be attached to the
unit.
When chest compressions begin, the X Series unit automatically starts filtering the CPR artifact
after detecting the first 3 to 6 compressions. The filtered ECG, with the label “FIL,” may be
displayed on the second or third trace (by selecting
FILT ECG in the Trace2 or Trace3 menu).
See-Thru CPR filtering continues as long as the OneStep CPR, OneStep Complete or
CPR-D-padz detect compressions and patient impedance is valid. When no compressions are
detected or one of the conditions noted above occurs, See-Thru CPR filtering stops, and
unfiltered ECG signals are displayed. When compressions resume, filtering automatically
restarts after 3 to 6 chest compressions.
Note: There is a delay of approximately 1/16 second between the See-Thru CPR waveform
and the Trace 1 ECG waveform.