Razi Journal of Medical Sciences

fa بررسی تداخلات امواج الکترومغناطیسی بین تلفن‎های همراه و دستگاه الکتروکوتر به جهت کمینه نمودن این اختلالات در مراکز درمانی Investigating Electromagnetic Wave Interference between Mobile Phones and Electrosurgical Device to Minimize These Disturbances in Medical Centers مهندسی علوم Biotechnology پژوهشي Research <div style="text-align: justify;">زمینه و هدف: اختلالات ناشی از حضور تلفن همراه در محیط‌های درمانی، به عنوان یکی از مسائل مهم و چالش‌برانگیز در حفظ ایمنی بیمار و عملکرد صحیح تجهیزات پزشکی میباشد. در این پژوهش، به صورت جامع و کمی، تداخلات امواج الکترومغناطیسی بین تلفن همراه و دستگاه الکتروکوتر بررسی شده است تا نتیجه آن مشخص شده و با استناد به آن از بروز بیشتر این تداخلات جلوگیری شود. روش کار: برای اندازه&lrm;گیری تاثیر میدان‌ الکترومغناطیسی حاصل از تشعشع یک گوشی تلفن همراه بر دستگاه الکتروکوتر، از یک دستگاه سیگنال آنالایزر و یک پروب الکترومغناطیسی با قابلیت اندازه&lrm;گیری فرکانس&lrm;های مختلف  استفاده شده است. سپس در شرایط متنوع تعداد و محل قرارگیری تلفن همراه نسبت به دستگاه الکتروکوتر، نمودار میدان مغناطیسی نشان داده شده توسط دستگاه سیگنال آنالایزر بررسی و تحلیل شده است. یافتهها: مقایسه نتایج نشان می&lrm;دهد که حضور تلفن همراه حتی در حالت روشن هم تاثیرگذاری خود را دارد که این اثر در حدود 5dB است. اما چیزی که واضح است این است که در فواصل دورتر این اثر کاهش می&lrm;یابد و تقریبا قابل اغماض است. ضمنا اگر تلفن همراه در حالت مکالمه یا انتقال داده باشد بیشترین اثر مخرب را دارد و این اثر هنگامی افرایش پیدا می&rlm;کند که بیش از دو عدد تلفن همراه در اتاق حضور داشته باشد. در این حالت حتی در فواصل دورتر از 50 سانتی‌متر هم اثر مخرب خود را می&lrm;گذارند. نتیجه‌گیری: باتوجه به یافته های این پژوهش نتیجه گرفته میشود که بروز تداخل امواج بین تلفن همراه و تجهیزات پزشکی از جمله الکتروکوتر امری اجتناب ناپذیر است و درصورتی که به دلایل ذکرشده (افزایش تعداد تلفن همراه یا کاهش فاصله آنها از دستگاه پزشکی) مقدار این امواج و میدان مغناطیسی ایجاد شده توسط آنها افزایش یابد، میتواند ایمنی بیمار را به خطر بیاندازد. جهت کاهش این تداخلات راهکارهای زیر توصیه می‌شود:</div> <ul> <li dir="RTL" style="margin-right: 48px; margin-bottom: 13px; text-align: justify;">طراحی تجهیزات با شیلدینگ مناسب و فیلترهای EMI</li> <li dir="RTL" style="margin-right: 48px; margin-bottom: 13px; text-align: justify;">تعیین فاصله حداقل ۱ تا ۲ متری گوشی از دستگاه‌های حساس</li> <li dir="RTL" style="margin-right: 48px; margin-bottom: 13px; text-align: justify;">آزمون‌های EMC پیش از استفاده از تجهیزات جدید در بیمارستان و...</li> </ul> <div style="text-align: justify;"></div> <div style="text-align: justify;">Background & Aims: The presence of mobile phones in clinical environments, particularly in sensitive areas such as operating rooms, is recognized as a significant and challenging issue concerning the safety and proper functioning of medical equipment. Despite strict prohibitions on mobile phone usage in these areas and strong recommendations from numerous guidelines, the lack of reliable scientific sources and documented evidence has made it difficult to conclusively demonstrate the extent and impact of such interference. This issue involves not only technical implications but also clinical, managerial, and even legal aspects. Given the proven sensitivity of certain medical devices—such as pacemakers—to electromagnetic waves emitted by mobile phones, tablets, and wireless devices, and the potential for these waves to disrupt device performance, there is a plausible risk that similar interference could affect other medical equipment as well. Numerous international studies [1, 2] have indicated that even modern smartphones can cause interference in the performance of electrosurgical units at distances of less than 1 meter. Furthermore, a 2011 study [3] demonstrated that radiofrequency (RF) emissions from mobile phones can interfere with medical equipment in intensive care units (ICUs) when used at close distances (less than 1 meter). That study, carried out in a hospital in India, recommended maintaining a minimum safe distance of 1 meter between mobile phones and medical devices. In this study, electromagnetic interference (EMI) between mobile phones and electrosurgical units is comprehensively and quantitatively investigated. The electrosurgical unit is a critical instrument in medicine, essential for numerous procedures and interventions. It utilizes the principles of electricity and heat to control bleeding and remove damaged or abnormal tissues within the surgeon's reach. Methods: The investigation of electromagnetic waves emitted by communication devices such as mobile phones is highly dependent on the specific type of medical equipment under study. In this project, the impact of mobile phone electromagnetic emissions on the Cavandish Systems electrosurgical unit, model MEG1, was examined. The process consisted of the following steps: Preparation and Setup: The first phase of the EMI test involved establishing a controlled environment that simulated the actual conditions in which the medical device is used. Test equipment—including signal generators, spectrum analyzers, and antennas—was installed to generate and measure electromagnetic fields. The device under test (DUT) was positioned to replicate real-world usage, with all cables and connections properly arranged. It was essential to ensure that the test setup complied with relevant standards and guidelines, such as those issued by regulatory bodies like the FDA or international standards such as IEC 60601-1-2. Testing and Evaluation: After completing the setup phase, the EMI testing began. The interference effects were evaluated by first measuring the radiation levels emitted by the mobile phone at the location of the DUT under worst-case conditions—such as when the phone was powered on, ringing, or during an active call. These measured values were then compared with the permissible limits specified in the device's datasheet. The results of each test were recorded according to the predefined criteria and compared under conditions of mobile phone presence versus absence. Each test was repeated at least three times on separate occasions to verify accuracy and ensure reproducibility. Additionally, to determine the acceptable safe distance, tests were conducted at several different points relative to the device. This study was carried out at the Hazrat Fatemeh (PBUH) Superspecialty Educational and Therapeutic Center of Plastic and Reconstructive Surgery. The findings can serve as a scientific and documented basis for developing practical and engineering guidelines aimed at preventing electromagnetic interference in medical devices. Results: The experiments were conducted under various mobile phone conditions (powered on, powered off, data transmission, ringing, and active call) and configurations (one, two, and three phones) at different distances from the device and its electrode. Each test was repeated at least three times to ensure accuracy and reliability. The summarized results are presented below. Mobile Phone Powered Off: This state served as the baseline for testing, as a powered-off phone emits no signals and therefore has no measurable effect on the electrosurgical unit. Mobile Phone Powered On: Tests were performed with the phone powered on and placed at distances of 10 cm, 50 cm, 1 m, and 2 m from the device, and were repeated with two phones. The results indicate that even in the standby (powered-on) state, the phone exerts a measurable influence of approximately 5 dB. However, this effect diminishes significantly with increasing distance and becomes negligible beyond 1 meter. The strongest interference occurs at 10 cm. Notably, placing the phone close to the main body of the electrosurgical unit is more disruptive than placing it near the electrode. Mobile Phone Ringing (Incoming Call): The results show that when the phone is ringing (i.e., during call initiation), its electromagnetic interference increases significantly compared to the standby state. Although the effect weakens at greater distances from the electrosurgical unit, it remains noticeable and can disrupt device performance. Importantly, in this state, both the device body and the electrode are similarly affected by the interference. Mobile Phone During Active Call: The findings indicate that during an active voice call, the level of interference is comparable to that of the ringing state. While the effect decreases with distance, it remains sufficient to cause operational disturbances in the electrosurgical unit. Similar to the ringing state, both the device body and the electrode are equally susceptible to interference during an active call. Mobile Phone During Data Transmission: When the mobile phone is engaged in data transmission, it causes disruptive interference even at distances greater than 50 cm, leading to performance issues in the electrosurgical unit. This harmful effect becomes more pronounced when the number of mobile phones increases to two or three, resulting in significantly stronger interference and a greater risk of device malfunction. Conclusion: The results demonstrate that even a mobile phone in the powered-on state can cause interference with the electrosurgical unit. The most significant harmful effects occur when the phone is engaged in a call or data transmission, and this interference intensifies when two or more mobile phones are present in the room. Specifically, a single mobile phone in data-transmission or call mode can affect the device within a range of up to 50 cm. However, as the number of phones increases, this interference range can extend up to 2 meters, negatively impacting the medical device's performance. </div> الکتروکوتر, تلفن همراه, تداخل, الکترومغناطیس Electrosurgical unit, Mobile phone, Interference, Electromagnetic 1 11 http://rjms.iums.ac.ir/browse.php?a_code=A-10-8699-1&slc_lang=fa&sid=1 Zahra Sabetghadam زهرا ثابت قدم z.sabetghadam@yahoo.com 3900319475328460091623 3900319475328460091623 Yes Medical Equipment Specialist, Food and Drug Administration, Iran University of Medical Sciences, Tehran, Iran کارشناس تجهیزات پزشکی، معاونت غذا و دارو، دانشگاه علوم پزشکی ایران، تهران، ایران