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Abstract: The exponential diffusion of wearable medical devices (WMD) in recent years has involved people of all ages, including workers. Workers who use WMDs should be considered at a particular risk from electromagnetic fields, and in accordance with EU Directive 2013/35/EU, they require an individual risk assessment. Currently, there is no international standard that provides specific guidance on how to perform such a risk assessment. This paper focuses on the effects of electromagnetic fields on WMDs and does not consider the direct effects on human body tissues. It aims to offer practical recommendations to employers and/or health physicists for the risk assessment of workers with WMDs. Focusing on EU countries, we first describe the requirements outlined by the technical standard for the electromagnetic compatibility (EMC) of medical electrical equipment EN 60601-1-2. Then, some general guidelines on how to perform the risk assessment are provided. The assessment can be conducted by comparing the field values measured in the workplace with the immunity test levels specified in the technical standards of medical electrical equipment. If the measured values are lower than the immunity test levels indicated in the standard and the distance from the electromagnetic source is greater than the distance used by the manufacturer during the EMC (electromagnetic compatibility) tests (typically 30 cm), the risk for the worker may be considered acceptable. However, if the measured values exceed the immunity test levels or the distance criteria, a specific evaluation based on a case-by-case analysis is required., (Copyright © 2024 Health Physics Society.)

Abstract: Pacemakers (PM) and implantable cardioverter defibrillators (ICD) are active implantable medical devices (AIMD) needed in case of cardiac arrhythmias. Given their potentially life-sustaining nature, the interaction between any source of electromagnetic field and these AIMDs is an ongoing concern of patients, industry, and regulators. According to the current regulatory framework, the required immunity of PM and ICD provides a reasonable unperturbed behavior in the presence of cell phones and base stations that use pre-5G technologies. PM/ICD international standards do not consider some peculiar characteristics of 5G technology and some of the 5G technology frequency bands (those above 3 GHz), since these frequencies are considered not to add risks to the AIMD functioning. Here we analyze the theoretical issues about the interference between 5G technology and PM/ICD and propose an experimental approach to perform a measurement campaign., (Copyright © 2023 Health Physics Society.)

Abstract: In 2017, the Italian National Institute of Health conducted a study to evaluate the potential risks of Conducted Electrical Weapons (CEW, AKA "stun guns") for users bearing a pacemaker (PM) or an implantable cardioverter defibrillator (ICD). The study addressed two specific models of stun guns: the TASER model X2 and AXON model X26P. In 2019, the same experimental protocol and testing procedure was adopted to evaluate the risk for another model of stun gun, the MAGEN model 5 (MAGEN, Israel). The MAGEN 5 differs from the previous stun guns tested in terms of peak voltage generated, duration of the shock, and trigger modality for repeated shocks. This note is an update of the previous study results, including the measurements on the MAGEN 5 stun gun. Despite the differences between the stun gun models, the effects on the PM/ICD behavior were the same as previously observed for the TASER stun guns., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2020 Health Physics Society.)

The aim of the study is to investigate systematically the possible interactions between two types of stun guns and last-generation pacemakers and implantable defibrillators. Experimental measurements were performed on pacemakers and implantable defibrillators from five leading manufacturers, considering the effect of stun gun dart positioning, sensing modality, stun gun shock duration, and defibrillation energy level. More than 300 measurements were collected. No damage or permanent malfunction was observed in either pacemakers or implantable defibrillators. During the stun gun shock, most of the pacemakers entered into the noise reversion mode. However, complete inhibition of the pacing activity was also observed in some of the pacemakers and in all the implantable defibrillators. In implantable defibrillators, standard stun gun shock (duration 5 s) caused the detection of a shockable rhythm and the start of a charging cycle. Prolonged stun gun shocks (10-15 s) triggered the inappropriate delivery of defibrillation therapy in all the implantable defibrillators tested. Also in this case, no damage or permanent malfunction was observed. For pacemakers, in most cases, the stun guns caused them either to switch to the noise reversion mode or to exhibit partial or total pacing inhibition. For implantable defibrillators, in all cases, the stun guns triggered a ventricular fibrillation event detection. No risks resulted when the stun gun was used by a person wearing a pacemaker or an implantable defibrillator. This work provides novel and up-to-date evidence useful for the evaluation of risks to pacemaker/implantable defibrillator wearers due to stun guns.

Objective: High blood pressure (BP) is associated with reduced pain sensitivity, known as BP-related hypoalgesia. The underlying neural mechanisms remain uncertain, yet arterial baroreceptor signaling, occurring at cardiac systole, is implicated. We examined normotensives using functional neuroimaging and pain stimulation during distinct phases of the cardiac cycle to test the hypothesized neural mediation of baroreceptor-induced attenuation of pain., Methods: Eighteen participants (10 women; 32.7 (6.5) years) underwent BP monitoring for 1 week at home, and individual pain thresholds were determined in the laboratory. Subsequently, participants were administered unpredictable painful and nonpainful electrocutaneous shocks (stimulus type), timed to occur either at systole or at diastole (cardiac phase) in an event-related design. After each trial, participants evaluated their subjective experience., Results: Subjective pain was lower for painful stimuli administered at systole compared with diastole, F(1, 2283) = 4.82, p = 0.03. Individuals with higher baseline BP demonstrated overall lower pain perception, F(1, 2164) = 10.47, p < .0001. Within the brain, painful stimulation activated somatosensory areas, prefrontal cortex, cingulate cortex, posterior insula, amygdala, and the thalamus. Stimuli delivered during systole (concurrent with baroreceptor discharge) activated areas associated with heightened parasympathetic drive. No stimulus type by cardiac phase interaction emerged except for a small cluster located in the right parietal cortex., Conclusions: We confirm the negative associations between BP and pain, highlighting the antinociceptive impact of baroreceptor discharge. Neural substrates associated with baroreceptor/BP-related hypoalgesia include superior parietal lobule, precentral, and lingual gyrus, regions typically involved in the cognitive aspects of pain experience.

The purpose of this study is to evaluate the potential for electromagnetic interference (EMI) and to assess the immunity level of implantable pacemakers (PM) when exposed to the radiofrequency (RF) field generated by Wi-Fi devices. Ten PM from five manufacturers, representative of what today is implanted in patients, have been tested in vitro and exposed to the signal generated by a Wi-Fi transmitter. An exposure setup that reproduces the actual IEEE 802.11b/g protocol has been designed and used during the tests. The system is able to amplify the Wi-Fi signal and transmits at power levels higher than those allowed by current international regulation. Such approach allows one to obtain, in case of no EMI, a safety margin for PM exposed to Wi-Fi signals, which otherwise cannot be derived if using commercial Wi-Fi equipment. The results of this study mitigate concerns about using Wi-Fi devices close to PM: none of the PM tested exhibit any degradation of their performance, even when exposed to RF field levels five times higher than those allowed by current international regulation (20 W EIRP). In conclusion, Wi-Fi devices do not pose risks of EMI to implantable PM. The immunity level of modern PM is much higher than the transmitting power of RF devices operating at 2.4 GHz.

Electromagnetic interference with critical medical care devices has been reported by various groups. Previous studies have demonstrated that volumetric and syringe pumps are susceptible to false alarm buzzing and blocking when exposed to various electromagnetic sources. The risk of electromagnetic interference depends on several factors such as the phone-emitted power, distance, and carrier frequency. The aim of this study was to assess the risk of GSM phone-induced electromagnetic interference with volumetric and syringe pumps, at various distances and emitted powers. Malfunctions were observed in 6 out of 8 volumetric pumps and in 1 out of 4 syringe pumps exposed to mobile phones at their maximum output, at distances up to 30 cm. The maximum power that did not induce any malfunction at zero distance was 50 mW at 900 MHz and 2.5 mW at 1,800 MHz. In state-of-the-art pumps, the presence of moderate-good base station coverage would significantly reduce the risk of electromagnetic interference.

We studied a possible correlation between autonomic cardiac activity and the level of the red blood cell acetylcholinesterase (AChE) in patients with probable Alzheimer disease (AD). The influence of cholinesterase inhibitor treatment on this autonomic activity was evaluated. Twelve patients satisfying the NINCDS-ADRDA criteria of probable AD and 10 healthy controls were studied. Autonomic cardiac activity was evaluated by means of power spectral analysis (PSA) of heart rate variability (HRV) using an autoregressive algorithm on 250 consecutive electrocardiographic R-R intervals. All patients received oral eptastigmine, a new cholinesterase inhibitor, for 1 month. Before treatment, a simultaneous recording of the electrocardiographic and respiratory activities was performed at rest and subsequently during head-up tilt test at 700. Recording was repeated on the last day of treatment. The level of AChE activity during each recording was also evaluated. Spectrum power was calculated in three main frequency bands: high frequency (HF), 0.15-0.4 Hz; low frequency (LF), 0.04-0.15 Hz; very low frequency (VLF), <0.04 Hz. In addition, we calculated the total spectrum power (TSP) and the LF/HF ratio. The TSP and the absolute value of each spectral component were significantly lower in AD patients than in controls. In contrast with controls, AD patients did not show any significant change before treatment in either the LF and HF components or in the LF/HF ratio during the tilt test. However, the modification in the LF component, induced by tilting, showed a significant correlation with the level of AChE activity (p < 0.03). During the tilt test, the treatment caused changes in LF and HF components and in the LF/HF ratio similar to those observed in controls. These results suggest that the presence of autonomic cardiac dysfunction in AD patients might be due to a cholinergic deficit in the peripheral autonomic nervous system. Some aspects of this autonomic dysfunction can be normalized by cholinesterase inhibitor treatment.