Physio Control LIFEPAK 20, Manual

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Clinical Summaries
B-8 LIFEPAK 20e Defibrillator/Monitor Operating Instructions
Figure B-2
Cumulative Shock Success for Intra-operative Defibrillation with Monophasic (MDS) and Biphasic
(BTE) Shocks: Observed Rates ( n ) Plotted with Estimated Dose Response Curves
Conclusions
The data demonstrate the Physio-Control biphasic waveform is clinically superior to the
conventional monophasic damped sine waveform for intra-operative internal defibrillation of VF.
Specifically, these biphasic shocks have higher defibrillation efficacy, while requiring fewer
shocks, less threshold energy and less cumulative energy than monophasic damped sine
shocks. There were no unsafe outcomes or adverse effects from the use of the biphasic
waveform.
Table B-3
Cumulative Shock Success Rates and Crossover Shock Results for Intra-operative Defibrillation
Energy
Setting
2 J 5 J 7 J 10 J 20 J
20 J Crossover
Successes
MDS: n = 41 7% 22% 34% 51% 76%
3 of 8 pts succeeded with
20 J BTE shock
BTE: n = 48* 17% 52% 67% 75% 83%
3 of 8 pts succeeded with
20 J MDS shock
*Two subjects randomized to the BTE group were unable to be included in the cumulative success rates shown
in the table and figure due to protocol deviations occurring after the 5 J shock.
% Succ
ess
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Energy Setting (J)
0 5 10 15 20
MDS
BTE