Children are much less likely to fibrillate and when they do, it is caused by severe metabolic or structural damage to the heart. Defibrillation alone is not likely to be enough in this situation. This makes a good outcome very unlikely. Some infection protection, more attractive option than mouth to mouth, can be supplemented with oxygen. List pros and cons of ambubags in this environment.
Pocket mask is probable the best choice here.
Although sales people say biphasic waveform is better, at this time, there is not enough evidence to believe this. Biphasic technology may be as effective, the same, or less effective than standard monophasic defibrillation. It is true, that the biphasic wave is easier to electronically produce. This results in smaller, cheaper, lighter, more battery efficient units. They also cause inappropriate analyzes.