Study on Electromagnetic Interference Risk of Active Implantable Medical Devices in Multiple Unit Environment / 中国医疗器械杂志

Concerning on the safety risks caused by electromagnetic interference of patients implanted with high-risk active implantable medical devices in the environment of domestic MUs, this study evaluates and focuses on the requirements of electromagnetic compatibility in domestic and international standards for rail transit vehicles, the main mechanism of risks caused by EMI, the actual measurement of environmental data in MUs and the working performance of various active implantables in the compartment. The test results shows that all kinds of active implantable medical device samples works normally in the CRH2A EMU in China, and there is still a large margin between the measured radiation emission in MU and the limit required by the standards.

Electrocirugía en procedimientos dermatológicos en pacientes portadores de dispositivos eléctricos cardíacos implantables / Electrosurgery in dermatological procedures in patients with implantable cardiac electrical devices

Debido al acelerado envejecimiento de la población, cada vez es mayor la cantidad de usuarios portado-res de dispositivos electrónicos cardíacos implan-tables (DECI). Muchos de estos pacientes se verán enfrentados a procedimientos dermatológicos que con frecuencia utilizan equipos de electrocirugía. Es-tos tienen riesgo potencial de producir interferencias electromagnéticas (IEM), y por lo tanto alterar el fun-cionamiento de estos dispositivos. Si bien no todos los DECI tienen las mismas características, las nuevas tec-nologías de estos dispositivos han disminuido, aunque no eliminado completamente, el riesgo de IEM. Este artículo tiene como propósito revisar el tema y recopilar las recomendaciones generales que todo dermatólogo debe conocer tanto en la fase preoperatoria, intraoperatoria, como postoperatoria al utilizar equipos de electrocirugía en un paciente con DECI.

Due to the accelerated population aging, an increa-sing number of users is carrying cardiac implantable electronic devices (CIEDs). Many of these patients will face dermatological procedures that often use electrosurgical equipment. The latter has the poten-tial to produce electromagnetic interference (EMI), and therefore alter the operation of these devices. While not all CIEDs have the same characteristics, new technologies for these devices have decreased if not eliminated completely the risk of EMI.The purpose of this article is to review CIED topic and compile general recommendations that every dermatologist should be aware of, both in the preoperative, intraoperative, and postoperative phases when using electrosurgery equipment in a patient with CIED.

Requirements and Countermeasures of Electromagnetic-compatibility for Medical Electrical Equipment / 中国医疗器械杂志

This article elaborates electromagnetic compatibility of medical electrical equipment and the regulatory tests based on related standards. And elaborating the diversity and the necessity of rectification by specific cases and deeply discussing and summing up for improving the compatibility of medical electrical equipment.

Research on influence on safety and efficiency of medical devices induced by RFID system / 中国医学装备

As a rising automatic identification technology, radio frequency identification (RFID) is receiving considerable attention and eliciting widespread interest in medical institutions in China. Some medical institutions have begun exploring and developing RFID systems for kinds of applications. A majority of medical institutions pay insufficient attention to the issue of RFID interference with medical devices. Specialized standards for the application of RFID in healthcare environments are desired. And there are misalignments between existing technology standards. Further researches should be developed to study the influence on safety and efficiency of medical devices induced by RFID system.

Endoscopic Electrosurgery in Patients with Cardiac Implantable Electronic Devices

BACKGROUND/AIMS: Patients with cardiac implantable electronic devices (CIEDs) undergoing endoscopic electrosurgery (EE) are at a risk of electromagnetic interference (EMI). We aimed to analyze the effects of EE in CIED patients. METHODS: Patients with CIED who underwent EE procedures such as snare polypectomy, endoscopic submucosal dissection (ESD), and endoscopic retrograde cholangiopancreatography (ERCP) with endoscopic sphincterotomy (EST) were retrospectively analyzed. Postprocedural symptoms as well as demographic and outpatient follow-up data were reviewed through medical records. Electrical data, including preprocedural and postprocedural arrhythmia records, were reviewed through pacemaker interrogation, 24-hour Holter monitoring, or electrocardiogram. RESULTS: Fifty-nine procedures in 49 patients were analyzed. Fifty procedures were performed in 43 patients with a pacemaker, and nine were performed in six patients with an implantable cardioverter-defibrillator. There were one gastric and 44 colon snare polypectomies, five gastric and one colon ESDs, and eight ERCPs with EST. Fifty-five cases of electrical follow-up were noted, with two postprocedural changes not caused by EE. Thirty-one pacemaker interrogations had procedure recordings, with two cases of asymptomatic tachycardia. All patients were asymptomatic with no adverse events. CONCLUSIONS: Our study reports no adverse events from EE in patients with CIED, suggesting that this procedure is safe. However, because of the possibility of EMI, recommendations on EE should be followed.

Design of electromagnetic compatibility in shelter hospital system / 医疗卫生装备

To explore the electromagnetic compatibility in the shelter hospital system to adapt it to the future complex electromagnetic environment. The factors for electromagnetic interference were analyzed, and some measures were put forward including separating the interference source from the sensitive device, setting up shielding space, applying grounding measures, eliminating interference signals by filtering and etc. The electromagnetic compatibility in the shelter hospital system was detected through electromagnetic self-compatibility test and electromagnetic environ-mental suitability test for external radio frequency. Simulations and tests proved that the failures and mal-re-sponse due to electromagnetic interference were avoided in the shelter hospital system. The electromagnetic compatibility scheme can meet the requirements of emergency medical facilities for electromagnetic protection in field conditions.

Electromagnetic interference reduction by dynamic impedance balancing applied to biosensors

INTRODUCTION: Electromagnetic interference caused by electric power lines adversely affects the signals of electronic instruments, especially those with low amplitude levels. This type of interference is known as common-mode interference. There are many methods and architectures used to minimize the influence of this kind of interference on electronic instruments, the most common of which is the use of band-reject filters. This paper presents the analysis, development, prototype and test of a new reconfigurable filter architecture for biomedical instruments, aiming to reduce the common-mode interference and preserve the useful signal components in the same frequency range as that of the noise, using the technique of dynamic impedance balancing. METHODS: The circuit blocks were mathematically modeled and the overall closed-loop transfer function was derived. Then the project was described and simulated in the VHDL_AMS language and also in an electronics simulation software, using discrete component blocks, with and without feedback. After theoretical analysis and simulation results, a prototype circuit was built and tested using as input a signal obtained from ECG electrodes. RESULTS: The results from the experimental circuit matched those from simulation: a 97.6% noise reduction was obtained in simulations using a sinusoidal signal, and an 86.66% reduction was achieved using ECG electrodes in experimental tests. In both cases, the useful signal was preserved. CONCLUSION: The method and its architecture can be applied to attenuate interferences which occur in the same frequency band as that of the useful signal components, while preserving these signals.

Magnets and implantable cardioverter defibrillators: What's the problem.

A growing number of surgical patients present to the operating room with implantable cardioverter defibrillators (ICD). Peri-operative care of these patients dictates that ICD function be suspended for many surgical procedures to avoid inappropriate, and possibly harmful, ICD therapy triggered by electromagnetic interference (EMI). An alternative to reprogramming the ICD is the use of a magnet to temporarily suspend its function. However, this approach is not without complications. We report a case where magnet use failed to inhibit ICD sensing of EMI, and a shock was delivered to the patient. Measures to decrease EMI, controversies regarding magnet use, and expert recommendations are discussed.

Discussion on the Defending Technologies for Military First-aid Equipments of the Army under Complex Electromagnetic Environments / 中国医学物理学杂志

Objective:To discuss the safety capability and defending technologies for military First-aid equipments of the army under complex electromagnetic environment.Methods:This paper analyzed the current status researching of the defending technologies for military First-aid medical equipments of the army,expatiated on the effect mechanism of the high power electromagnetic radiation on the medical equipment,and discussed the defending and reinforcing technologies.Results:The current military First-aid medical equipments of the army are of a sort defending capability,and it will have important significance to strengthen the study on the anti-electromagnetic interference technologies.Conclusion:The defending and reinforcing technologies discussed in this paper could enhance the subsistence capability of the military First-aid equipments under complex electromagnetic environments.

Avaliação do ambiente eletromagnético em estabelecimentos assistenciais de saúde / Electromagnetic environment assessment in health care facilities

A crescente inserção de tecnologia eletroeletrônica em estabelecimentos assistenciais de saúde (EAS), seja como equipamentos terapêuticos, de diagnóstico ou até mesmo suporte vital, tem sido vista pela comunidade científica como a grande responsável pelo aumento dos níveis de energia eletromagnética emitidos ao ambiente hospitalar. Dessa forma, quando a energia eletromagnética presente no ambiente atinge um determinado nível crítico, fica estabelecida uma situação que é propícia ao aparecimento de dois fenômenos indesejados: a interferência eletromagnética (EMI) em equipamentos médicos, e os riscos biológicos (RBL) em seres vivos. Um importante recurso para gerenciar a compatibilidade eletromagnética e evitar o aparecimento destes fenômenos é o conhecimento das características eletromagnéticas presentes nestes ambientes. O objetivo deste trabalho é diagnosticar o comportamento eletromagnético estabelecido em ambientes de grande concentração de fontes emissoras como, por exemplo, o encontrado em centros cirúrgicos, através de uma série de medições in situ das grandezas eletromagnéticas envolvidas nestes meios (campos elétricos, campos magnéticos, ruídos conduzidos). Com base nestas medidas é realizada uma avaliação crítica de modo a comparar a situação estabelecida nos EAS e os limites de segurança preconizados por organismos competentes, tanto para EMI quanto para RBL. Como resultado desta análise, começa a existir maior discernimento quanto à real situação do ambiente eletromagnético encontrado em EAS nacionais, subsidiando informações para a definição de diretrizes mais eficientes para implementação de programas de gestão tecnológica que são direcionados às necessidades específicas destes hospitais.

Advances in technology and the increased use of electro-medical equipment (EME) to support medical procedures such as monitoring, diagnosis, therapeutic or even life support are considered as greatly responsible for the increase of electromagnetic energy within health care facilities (HCF) environments. In such circumstances, when electromagnetic energy reaches a certain critical level, a dangerous situation is established and two undesirable phenomena can take place, both electromagnetic interference (EMI) in medical equipment, and biological risks (BLR) in living beings. The knowledge of electromagneticcharacteristics shown by these environments can represent an important tool in order to promote electromagnetic compatibility and avoid the appearance of undesirable phenomena. Therefore, this work aims to diagnose the electromagnetic profile established in critical areas, such as operating rooms, through a number of “in situ” measurements concerning electromagnetic quantities present in this environment (electric field, magnetic field, conducted noise). Moreover, a critical evaluation follows in order to compare the establishedsituation within HCF and the safety levels prescribed by regulatory organizations regarding EMI and BLR. As a result of this assessment, a better understanding on the actual situation concerning the electromagnetic environment in HCF can be achieved, allowing clinical engineers to define better directives in order to implement an adequate management programs in these hospitals.

In site electric field measurementos in hospital operating rooms / Medição de campos elétricos in situ em centros cirúrgicos

A interferência eletromagnética pode causar problemas no funcionamento de equipamentos eletromédicos. Dentre as fontes radiantes de interferência encontradas na literatura, os telefones celulares e as unidades eletrocirúrgicas vêm recebendo atenção especial. Rotineiramente, essas fontes operam simultaneamente em pequenos espaços físicos, como as salas cirúrgicas. Este estudo apresenta uma sondagem da intensidade de campo elétrico ambiente em salas cirúrgicas durante a intervenção médica. As medições aconteceram em centros cirúrgicos de três hospitais com o emprego de um medidor isotrópicos de campo elétrico com sensor calibrado. Sete diferentes tipos de cirurgia foram monitorados. Para evitar a obtenção de intensidades de campo discrepantes nas medições, os experimentos aconteceram nas salas cirúrgicas disponíveis que apresentaram disposição similaar de objetos e móveis cirúrgicos e equipamentos eletromédicos. O medidor de campo adquiriu as medidas em quatro pontos ao redor da mesa cirúrgica. A comunicação remota entre o medidor dentro da sala cirúrgica e um computador portátil fora da sala foi estabelecida por meio de um cabo de fibra ótica. Quinze minutos em cado ponto totalizaram 1 hora de observação por cirurgia. O medidor registrou valores de campo elétrico mais elevados que o nível basal quando do acionamento da unidade eletrocirúrgica. O valor médio de campo elétrico variou entre 1,1 mais ou menos 0,3 V/m e 3,0 mais ou menos 1,2 V/m. Contudo, intensidades mais elevadas de campo elétrico foram observadas, como 9,1 V/m, para distâncias maiores que 2,0 m. Os campos elétricos registrados resultam da integração de todos os campos existentes no espectro de freqüências que o medidor é capaz de monitorar. Por esse motivo, o medidor não consegue determinar os campos elétricos na freqüência de operação de um equipamento eletrodoméstico específico, diferentemente de um analisador de espectro. Porém, ele apresentou o impacto causado pela ativação da unidade eletro...

Anesthetic Experience of Appendectomy of a Patient with Implantable Cardioverter Defibrillator: A case report / 대한마취과학회지

Implantable Cardioverter Defibrillator (ICD) devices have been developed for prompt recognization and termination of life-threatening ventricular arrhythmias. We experienced a case of 34-years old male patient with ICD diagnosed as Brugada Syndrome and undergone appendectomy under general anesthesia. Before anesthetic induction, the device was turned off to avoid electromagnetic interference (EMI) from electrocautery during operation and turned on again after surgery. There was no significant cardiac events during perioperative period and postoperative care for 7 days of admission.

Mitigating EMI with healthcare electronic facilities referring to FDA recommendations / 医疗卫生装备

In view of China's medical equipment industry has not been equipped with a sound system and strict administration, it is wise to draw on FDA recommendations and seek effective ways of solving EMI problems. Further should focus on improving the performance of medical equipment so as to adapt to the different environment. In the end, the design of healthcare facilities to meet EMC standards is put forward specifically in four parts of electronic circuits, power circuits, display device, and the mechanical shell.

Existent Question and Strategy of Medical Equipment Under Complex Electromagnetic Environment / 医疗卫生装备

The future war will inevitably to be in the land,the sea and the sky and so on hyperspace,and electromagnetic environment is very complex.How to eliminate interference of medical equipment under the complex electromagnetic environment,to promote the performance of the medical support,these is austerity and reality questions in current every level of medical and health organization.Only based on the existing,bold practice,independent innovation,the comprehensive medical support exercise under the complicated electromagnetic environment,to master various types of medical equipment in a complex electromagnetic environment of the characteristics and laws in order to give full play to existing health technologies and equipment performance,improve the timeliness of medical support.