Susceptibility of automated external defibrillators to train overhead lines and metro third rails

Future shock: automatic external defibrillators

“…However, susceptibility to highpower lines (such as those used in train and metro terminals) has raised concerns regarding whether current AED models should be used in certain public locations [26,27 ]. In their study, Kanz et al [27 ] concluded that the AED models examined 'were unsuitable for automated defibrillation [in these settings] as these devices demonstrated an unacceptable performance in respect of accuracy and safety'.…”

Removal of electrocardiogram distortion in portable high-power medical device

“…Among these medical devices, automated external defibrillator (AED) has become an essential medical device with the tendency of increase in cardiovascular diseases, and each country advises to necessarily provide AEDs within public places, trains, cinemas, planes, and etc., [5,6]. To allow even the ordinary people to use AEDs at cardiac arrest, they are designed in simple and intuitive interfaces for automatic diagnosis of heart conditions, charging and delivery energies for defibrillations.…”

Interference of 16.7‐Hz electromagnetic fields on measured electrocardiogram

“…The influence of EMI from 16.7-Hz ac power lines on the function of electrocardiogram (ECG) devices and automated external defibrillators (AED) causing life-threatening risks to patients has recently gained special attention [Kanz et al, 2004;Schlimp et al, 2004;Schlimp et al, 2005a;Fleischhackl et al, 2006]. The appearance of 16.7-Hz EMI is basically restricted to the widely used electrified railroad systems and overland power lines in five European countries with approximately 110 million inhabitants.…”

“…This 16.7-Hz EMI overlaps the typical frequency spectra of 0.05-150 Hz of conventional ECG monitors. Kanz et al [2004] tested AED models in a specified metro setting with small train engines and observed severe malfunctions of some AED models already under conditions of low magnetic fields from 0.7 to 3.7 mT. It is notable that current variations in railroad power lines elicited by the acceleration and deceleration of locomotive engines operated in double traction systems can range up to 2000 A, corresponding to approximately 70 mT on the bottom of the railroad platform (Eq.…”

“…Therefore, in case that the stray capacitances are equal the resulting differential voltage at the input of the AED amplifier is negligible and could not be observed in the recorded ECG when the ECG device and the wires were in the same horizontal plane as the test person's chest. EMI in the ECG depends on the axis of the test person's ECG lead in relation to the course of the power line and is pronounced in a lead that is parallel to the power line and minimal in a lead at a 908 angle (perpendicular) thereto [Kanz et al, 2004;Schlimp et al, 2004]. 16.7-Hz EMI observed in the recorded ECG depends on the thoracic impedance of the body, the differences in electrode impedance and the asymmetry of the measurement channel of the ECG device.…”