Survival rate rises when the time taken to begin defibrillation lessens. While CPR helps in providing some blood flow to the brain and heart in response to a fatal arrhythmia, it is unable to directly refresh an organized rhythm. There is a much higher chance of restoring an organized rhythm with defibrillation and immediate CPR. The defibrillation disrupts the body’s chaotic rhythm, which helps to continue normal and effective electrical activity by restoring the heart’s usual pacemakers.
The defibrillator’s design—biphasic or monophasic—determines the appropriate energy dose. Monophasic defibrillators require a single 360 J shock, with exactly the same energy dose for the following shocks. Biphasic defibrillators are more effective when dealing with a fatal arrhythmia, as they utilize waveforms. The energy dose of the biphasic defibrillator depends on the manufacturer’s recommendations. If the arrhythmia is not terminated by the first shock, you may consider escalating the amount of energy.
Continue administering CPR during the defibrillator’s charging to minimize interruptions. Ensure that oxygen is removed and that no individual, including yourself, is in contact with the patient before delivering the shock. CPR should be administered for five cycles, or about two minutes (each cycle consists of 30 compressions then two breaths for individuals without an advanced airway). For those with an advanced airway, a rate of one breath every 5 to 6 seconds (or 10 to 12 breaths per minute) is acceptable.