Does Defibrillation Obey the Fundamental Law of Electrostimulation?
Since the introduction of external DC defibrillation, it has been common to use the energy as the defibrillation dose. This has historical reasons, as external defibrillators could not measure the voltage applied to the paddles, the current, or the duration of the pulse, as is usually done in electrostimulation. The only measurable quantity was the voltage to which the output capacitor was charged. Using the well-known formula that the stored energy is equal to half the capacitance of the charged capacitor times the voltage squared, the manufacturers were able to specify the energy of a pulse. This expedient in defining the dosage has greatly influenced the thinking of those engaged in defibrillation. Nonetheless, one has to ask whether the current practice is in accordance with the theories of electrostimulation and, if not, whether defibrillation obeys the laws of electrostimulation!
KeywordsField Strength Implantable Defibrillator Excitable Tissue Biphasic Pulse Distortion Factor
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