METHOD AND APPARATUS FOR GENERATING ADAPTIVE N-PHASIC DEFIBRILLATION WAVEFORMS

摘要

A method and apparatus for delivering an adaptive n-phasic waveform to the heart in either a fixed-tilt delivery mode or a fixed-duration delivery mode. A first phase of a first polarity is delivered to the heart. The first phase is set to terminate upon decaying to a preset level. If the first phase does not decay to the preset level within a predetermined maximum period of time, the first phase is terminated and the subsequent phases are delivered in a fixed-duration delivery mode. Because the first phase did not decay fast enough, it is determined that the patient has a relatively high system impedance. Therefore, subsequent phases will be delivered to the patient in a fixed-duration mode to ensure the defibrillation is reversed. Otherwise, if the first phase decays to the preset level in less than the maximum predetermined period of time, it is determined that the patient has a relatively low system impedance and subsequent phases should be delivered in a fixed-tilt mode.