Abstract: A defibrillator which may be portable and which may be used without relying on electrical supply mains. The apparatus comprises a capacitor, an inductance and a pair of electrodes whereby the capacitor is discharged through a patient and the selection of the energy level, the capacitor and the inductance being such that the voltage wave-form of the discharge pulse has a duration of between ten and fifteen milliseconds, a peak value of not more than 4 kilovolts and a minimum rise time to that peak of 1,000 microseconds.

Abstract: A portable defibrillator to inflict an electric shock on patients comprises a pair of electrodes to be connected to the patient and a circuit to pass a shock of given magnitude and duration through the electrodes and patient, the circuit being contained in housings on which the electrodes are mounted so that the defibrillator is fully portable.