Design and Implementation of Portable Auto Defibrillator

Abstract

Sudden Cardiac Arrest (SCA) is a case that made the heart stop pumping the blood. Ventricular fibrillation (VF) and ventricular tachycardia (VT) are the major causes that lead to cardiac arrest. To treat SCA, a defibrillator device is used to return the heart to its normal sinus rhythm. The main generation of the defibrillator is the manual type which has many limitations involved., It requires the physician’s instruction to determine the patient state and the amount of joule required; therefore, it is preferable to design an auto defibrillator. The aim of this paper is to design a hardware implementation system of auto dc-shock utilized in the emergency case for diagnosing patient case and recovering the normal state of the heart. This prototype consists of five main parts, including the diagnosing system, high voltage section, charging unit, discharging unit, and safety unit. The output of diagnosing system is followed by charging and discharging period in order to get a suitable amount of joule according to patient situation of 50, 100, 120, and 150 joule discharged on the patient body by using a biphasic system provided by safety mode circuit so that the discharge process automatically happens in the case of not discharged on the patient body. The proposed diagnosing system in hardware design was tested on several patients in Ibn al-Nafis hospital and healthy patients at home and the accuracy was achieved of 97.03%, specificity is 97.8%, and the detection error rate is 3.09%.