The monophasic wave of electric defibrillation is 360J, and the bidirectional wave is 150~200J.
The position of electric defibrillation: the center of the cardiac base electrode is located at the intersection of the right midclavicular line and the second intercostal space; the center of the cardiac apical electrode is located at the intersection of the left anterior axillary line and the fifth intercostal space (in the anterolateral position). Electrical defibrillation is a method of stopping ventricular fibrillation by shocking the heart with a certain amount of electric current. It is an effective treatment for ventricular fibrillation, and DC defibrillation is the most widely used method today.
Expanded:
The voltage converter converts the DC low voltage into pulsed high voltage, which is rectified by the high voltage and then charged to the energy storage capacitor C, so as to make the capacitor obtain a certain amount of energy storage. When defibrillation treatment, the control of high voltage relay K action, so that the charging circuit is cut off, by the energy storage capacitor C, inductance L and the human body (load) connected in series.
To make it constitute the RLC (R for the human body resistance, the wire itself resistance, the human body and the electrode contact resistance of the sum of three) series resonance attenuation oscillation circuit, that is, for the damping oscillation discharge circuit, through the human heart of the current waveform shown in Figure 6-1-2.
Experimental and clinical evidence suggests that this kind of RLC discharge of bidirectional spike current defibrillation effect is better, and less damage to human tissue. As mentioned earlier, the discharge time is generally 4 to 10 ms.
This can be achieved by selecting L and C appropriately. Inductor L should be used open iron core coil, in order to prevent the discharge due to high current caused by iron core saturation caused by the inductance value of the drop, and the output waveform changes. In addition, the presence of high voltage in defibrillation poses a risk of accidental electric shock to both the operator and the patient, so it is necessary to prevent incorrect operation and adopt various protective circuits.
Baidu Encyclopedia-Electrical Defibrillation