How many defibrillator shocks are given during an unsuccessful resuscitation attempt?
One shock for every two minutes of cardiopulmonary resuscitation is the official algorithm, especially if there is a shockable rhythm like ventricular fibrillation. So if the resuscitation is continues for 30 minutes as is usual, upto 15 shocks may be delivered. It all depends on the other conditions like the type of underlying disease and predicted feasibility of return to a good quality of life. In those who are terminally ill and with a “do not resuscitate” instruction, no resuscitation may be attempted at all.