Rhythmx® Aed Ecg Analysis Algorithm - Cardiac Science Powerheart G5 User Manual

C
ECG Analysis Algorithm and Rescue Waveform
Contents
◆ RHYTHMx® AED ECG analysis algorithm .................................. C-1
◆ Rescue protocol ................................................................................ C-1
◆ STAR® biphasic waveform .............................................................. C-1
This section describes the ECG analysis algorithm and Star Biphasic waveform.
RHYTHMx® AED ECG analysis
algorithm
The RHYTHMx AED ECG analysis algorithm provides extensive ECG
detection capabilities.
◆ All ventricular fibrillation (VF) are classified as shockable.
◆ Asystole is separated primarily by amplitude. ECG rhythms of low
amplitude are classified as asystole and are not shockable.
◆ The AED detects noise artifacts in the ECG form, generated from,
for example, movement of the patient, adjustment of the defibril-
lation pads, or electronic noise from external sources. The analysis
is delayed or aborted in these cases.
◆ The AED can detect or reject pulses from an implanted
pacemaker.
In addition, RHYTHMx optionally shocks selected VT and SVT
rhythms. Settings for several detection features can be adjusted
through AED Manager software:
◆ Detection rate—All ventricular tachycardia (VT) rhythms at or
above this rate are classified as shockable. All rhythms below this
rate are classified as non-shockable.
◆ Non-committed shock—If the patient's rhythm changes to a
non-shockable rhythm before the actual shock is delivered, the
AED cancels the shock.
◆ Synchronized shock—The AED automatically attempts to syn-
chronize shock delivery on the R-wave if one is present. If delivery
cannot be synchronized within one second, a nonsynchronized
shock is delivered.
◆ SVT discriminator—The AED is configurable to shock SVT
waveforms that are above a threshold rate that can be pre-set, or
can be disabled (default setting).
Powerheart® G5 Automated External Defibrillator
Rescue protocol
The AED rescue protocol is consistent with the guidelines recom-
mended by the AHA/ERC 2010 Guidelines for Resuscitation and
Emergency Cardiac Care.
Note: For consistency with AHA/ERC guidelines, the CPR time can
be set to allow for 5 cycles of 30 compressions and 2 breaths.
Use AED Manager to change the protocol. For details, see the AED
Manager User's Guide.
STAR® biphasic waveform
The waveform generated by the Cardiac Science AED is a biphasic
truncated exponential waveform. The waveform complies with the
IEC 60601-2-4 standard. Figure 1 is a graph of the waveform voltage
as a function of time when the AED is connected to a 50 ohm resistive
load using preinstalled pads (model number XELAED001.)
2000.0
1500.0
1000.0
V1
T1
500.0
0.0
-500.0
-1000.0
-1500.0
-1.000 0.000 1.000 2.000 3.000 4.000 5.000 6.000 7.000 8.000 9.000 10.000
Figure 1: High variable energy waveform with 50 ohm resistive load
Patient impedance
The Cardiac Science Biphasic Truncated Exponential (BTE) waveform
uses variable energy. The actual energy delivered varies with the
patient's impedance. The device delivers a shock to a patient with an
impedance in the range of 25 - 175 ohms. Energy is delivered at up to
three different levels: ultra-low variable energy, low variable energy,
and high variable energy (see the waveform and energy tables on the
following pages).
T2
V2
Time (ms)
C-1
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