Development Of Standard Defibrillation Energy Source

Defibrillator plays an important role in emergency system. While rescuing patients with Sudden Cardiac Arrest(SCA), defibrillator may cure abnormal heart rhythms by releasing pulse current, which would flow through the heart. The accuracy of energy released form defibrillator is an important technical parameter, and it decides whether the patient can be saved. Almost all the medical metrology institutions test the accuracy of energy with defibrillator analyzer, but the traceability system of defibrillator analyzer is faulty. In our lab, defibrillators are calibrated by the factory methods which must open the cabinet. The calibration of defibrillator analyzer is difficult to form a unified standard, and can’t meet the basic requirement of calibration.In this thesis, the algorithm of calculating the defibrillation pulse is analyzed, and the module testing defibrillation pulse energy is designed by using STM32. And the standard defibrillation energy source is designed with the energy testing module. The standard defibrillation energy source may release both monophasic waveform and biphasic waveform pulse, and it can display the standard value of defibrillation energy. The standard defibrillation energy source designed in this thesis may used as the standard device while calibrating the defibrillator analyzer, the development of this energy source perfected the traceability system of defibrillation pulse energy, and would insure to be effective and safe while using defibrillator.This thesis focuses on the following aspects:1. The methods of energy measurement and the Simpson numerical algorithm are studied after analyzing the principle of generating monophasic waveform and the waveform characteristic. 2. The circuit used to test energy of defibrillation pulse is designed by STM32, and the software system is developed to calculate the pulse energy accurately. The standard defibrillation energy source is designed with energy testing module and discharging module which is improved to discharge both monophasic waveform and biphasic waveform. 3. The standard defibrillation energy source have been evaluated by discharging to different defibrillator analyzers. The accuracy and error repeatability of the standard defibrillation energy source is evaluated to be qualifiedInnovation in this thesis are listed as follows:1. A new testing module which calculates energy with voltage and current is designed, and the module is not rely on load resistance. And Simpson algorithm is used to diminish error. 2. The standard defibrillation energy source is first proposed, and the it can release both the monophasic waveform and biphasic waveform. The design of this standard defibrillation energy source provided a standard device while calibrating the defibrillator analyzer, and the traceability system of defibrillation energy is perfected.