Physio-Control LIFEPAK 1000 - Manual (Page 62)

Shock Advisory System
B-2 LIFEPAK 1000 Defibrillator Operating Instructions
A number of activities can create motion, including CPR, rescuer movement, patient movement,
vehicle movement, and some internal pacemakers. If variations in the transthoracic impedance
signal exceed a maximum limit, the Shock Advisory System determines that patient motion of
some kind is present. If motion is detected, the ECG analysis is inhibited. The operator is
advised by a displayed message, a voice prompt, and an audible alert. After 10 seconds, if
motion is still present, the motion alert stops and the analysis always proceeds to completion.
This limits the delay in therapy in situations where it may not be possible to stop the motion.
However, the rescuer should remove the source of motion whenever possible to minimize the
chance of artifact in the ECG.
There are two reasons why ECG analysis is inhibited when the motion alert occurs, and why the
rescuer should remove the source of the motion whenever possible:
• Such motion may cause artifact in the ECG signal. This artifact may occasionally cause the
Shock Advisory System to reach an incorrect decision.
• The motion may be caused by a responder's interventions. To reduce the risk of inadvertently
shocking a responder, the motion alert prompts the responder to move away from the patient.
This will stop the motion and ECG analysis will proceed.