An extended h-bridge circuit for generating biphasic sawtooth discharge waveforms in cardiac defibrillators

Abstract

The invention belongs to the technical field of medical electronics, in particular to an extended H-bridge circuit in a defibrillator capable of generating a biphasic sawtooth discharging waveform. The H-bridge circuit consists of at least one energy storage capacitor, an inductive coil, a current sensor and a plurality of control switches, wherein the control switches are in parallel connection to form an extended H-bridge circuit switch with three vertical arm bridge circuits and two transverse arm bridge circuits; the control switches form a high-voltage discharging circuit according to a scheduled time sequence; and the high-voltage discharging circuit outputs diphasic pulse defibrillation current in a biphasic sawtooth wave pulse type to a patient to terminate ventricular fibrillation in a body and conduct rescue on the patient in time. With the adoption of the H-bridge circuit, requirements on high-voltage characteristics of a discharging bridge circuit can be lowered and device cost can be saved, individual and accurately controlled defibrillation electric energy can be provided for the patient, the success rate of cardiac shock defibrillation can be increased, and myocardial injuries in a high-voltage defibrillation process are decreased.

Description

technical field [0001] The invention belongs to the technical field of medical electronics, and in particular relates to a high-voltage discharge circuit for cardiac defibrillation, in particular to an extended H-bridge circuit used in an automatic external defibrillator (AED) for generating biphasic sawtooth discharge waveforms. Background technique [0002] Sudden cardiac death (SCD) is an unexpected circulatory collapse that occurs immediately within 1 hour of clinical symptoms, leading to cardiac arrest, and is the main cause of death from cardiovascular diseases. The epidemiological research results of the Center for Health Statistics in the United States show that more than 50% of all cardiovascular disease deaths are SCD, and the total number of SCD cases in my country is more than 544,000 cases every year; at the same time, in the past few decades, with the aging of the population The occurrence of process SCD is on the rise. Among them, 80% of SCDs are attributed to...

AI Technical Summary

Problems solved by technology

Although the above patents and biphasic defibrillation waves are used, the positive phase and reverse phase are essentially only one wave, which is in the form of high-voltage exponential decay and decline.

Its main disadvantages are: (1) The peak portion of the exponential wave exceeds the defibrillation threshold, which wastes energy and is likely to cause excessive stimulation and damage the myocardium; (2) The energy control deviation is large, and the energy released by the defibrillator depends on the chest. Impedance adjustment is difficult to achieve individualized and precise control, especially for patients with extremely high or low impedance; (3) The peak part of the exponential wave requires a higher initial voltage of the capacitive energy storage device and a higher withstand voltage. Fibrillation output stage, increasing the design complexity and manufacturing cost of defibrillator equipment

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