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Defibrillator Energy E = ½CV² — FRCA Primary MCQ

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ModeratePhysics & Clinical MeasurementDefibrillator Energy E = ½CV²FRCA Primary

Regarding the physics of defibrillation the energy stored in a defibrillator capacitor is calculated as:

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Correct answer: E — E = ½CV² (where C = capacitance and V = voltage)

Energy stored in a capacitor: E = ½CV² where C = capacitance (Farads) and V = voltage (Volts). The defibrillator charges a capacitor to a high voltage then discharges through the patient's chest. Biphasic waveforms deliver current in both directions and are more effective at lower energies than monophasic waveforms.

Reference: Al-Shaikh Stacey 2019 Essentials of Anaesthetic Equipment