FPGA Based Wireless Emergency Medical System for Developing ...

2015 Annual Global Online Conference on Information and Computer Technology

FPGA based wireless emergency medical system for developing countries Shivangi Agarwal, Asha Rani, Vijander Singh, Member, IEEE, A.P.Mittal Division of Instrumentation and Control Engineering, NSIT Sec-3 Dwarka, University of Delhi, New Delhi, India {agarwal.shivangi, ashansit, vijaydee, mittalap}@gmail.com

India should have better EMS to meet the growing number of emergency mass casualties, natural disasters or national emergencies. Pre-hospital care during any emergency medical situations, is the key for saving lives. Acute coronary syndrome(ACS) is curable if diagnosed quickly [4].The EMS should be designed to meet the needs of the cardiac emergency systems, systems for monitoring neurological disorders, noninvasive monitoring of respiratory rate, blood pressure monitoring etc. in developing countries. Previous research of developed countries shows that MDR (Medical Disaster Response)[6] project deals with specially trained local healthcare providers but the proposed research can deal with even a common man & volunteers present around the site, even when trained nurses and healthcare professionals are not present. A previous study [5] shows that present healthcare system does not meet the needs of increased mortality from cardiovascular disease. In the present research cardiac EMS is proposed to meet the emerging health care requirements. Proposed research can save few more lives due to its timely intervention and can monitor more than one patient while earlier systems monitors single patient [1] (figure 2b.). C.C. Chou and W.C. Fang et. al. designed a system to monitor [15] 3-lead ECG waveform of single patient while present research proposes the monitoring of multiple ECG waveforms of more than one patient The FPGA based EMS is one of the most integrated systems and an initiative to strengthen the concept of EMS in India. Most of the population of India resides in rural areas that do not have facility of EMS. Making a step forward in this direction, the proposed system will help in making fast analysis of life threatening clinical syndromes like cardiac anomalies: acute coronary syndrome, tachycardia & bradycardia etc., that require prompt diagnosis. Due to the cost effectiveness of the proposed medical system, NGO’s can afford it & help the patients during emergency. It can be used at primary health centres in villages where electricity is not available. This system is also useful for old age homes and creates a layer of protection for senior citizens. The Proposed FPGA based medical system is applicable both for outside& inside hospital use. Outside the hospital in emergency medical services, it helps first responder to take action to save the life of the patient. Inside hospital in emergency room or in ICU (Intensive Care Unit), system is easy to use where every second counts.

Abstract- In developing countries like India the translational gap between research development & implementation to routine clinical applications is high. To bridge this gap, a research methodology related to the development of emergency medical system & implementation of pre-hospital care is proposed. In order to provide comfort & convenience to first responders & paramedics, system is highly portable due to its light-weight The present work explores the use of low cost FPGA-based medical system in emergency medical situations where high processing speed is required.. The design system incorporates the FPGA, user interface components and wireless connectivity is provided with an extra module. Xilinx’s Spartan 3E starter kit by Digilent is chosen for the development of proposed medical system. FPGAbased designs offer a lot of flexibility in terms of updating the system & can be transformed to larger and newer FPGAs as the market demands. The proposed system can become one of the major constituents of the EMS (Emergency Medical Services) as it has the unique feature of monitoring multiple EKG waveforms which is not available in conventional hardware design [1]. IndexTerms- FPGA(Field Programmable Gate Array); EMS (Emergency Medical Services); EKG(Electrocardiogram,ECG)

I. INTRODUCTION EMS is an important part of overall healthcare system of any country. Indian EMS is still in its infancy because emergency medicine was recognised as a subject in 2009[2]. In spite of tremendous development has been made in the medical care over the past decade, India has to establish a single, comprehensive EMS that can be available all over the country. The EMS should not be thought as the regional health disaster organisation [6]. It is the emergency medical organisation that will work with other services during a casualty to provide emergency medical care [6]. In modern EMS systems patient is brought to the doctor or doctor is brought to the patient, still an early idea. The proposed medical system makes physician more efficient and results in better prehospital care. EMS in India has better facilities in comparison to other developing countries, but not ideal one. India still needs a lot of health facilities and better integrated systems. As per World Health Organization (WHO) survey, due to inadequate EMS around 30 percent of people die [3]. Therefore, EMS should be strong enough to provide the state -of-the-art facilities [3]. 978-1-5090-2314-1/16 $31.00 © 2016 IEEE DOI 10.1109/GOCICT.2015.23

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Fig. 1 Block Diagram of the FPGA based EMS.

II. SYSTEM DESCRIPTION The Proposed medical system is shown in figure 1, it can also be called as cardiac triage system as it displays EKG waveforms. By observing the waveforms cardiologist can diagnose the severity of disease. On the basis of triage, patients can be given pre hospital care & thus patient’s life can be saved. Thus proposed research can play an important role in EMS. Features of the proposed system are: x System is very simple & easy to use, even common man & volunteers present around the site may help in handling the system & can send images to doctors & healthcare experts.

x x x x

Highly portable due to its light weight. System is robust [7] so can be used in challenging operating conditions. System is able to monitor multiple ECG waveforms, and heart rate [1]. Hardware handling is reduced as many patients can be monitored with the same system at the same time. With this proposed medical system, 2-Lead EKG or two patients having single lead EKG can be monitored at the same time as shown in figure2(a).

Fig. 2 (b) Previous hardware design [1] shows only vital signs of single patient

Fig. 2 (a) Proposed medical system shows heart rate as well as EKG waveforms of two patients at the same time

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The block diagram of proposed system includes different modules which are as follows: A. ECG Signal Acquisition module For testing purpose ECG signal of MIT-BIH arrhythmia database is taken through function generator. In addition to this, raw ECG can also be acquired through reconfigurable analog front end (AFE) circuit as shown in figure 3 proposed by C. Tsai et al [8]. AFE circuit is a set of analog signal conditioning circuitry that uses op-amp, filter, and other circuits to provide a configurable and flexible electronics functional block.

Fig. 4 Proposed system powered by solar panel, battery backup & batteries of the vehicles

C. Wireless connectivity module Wireless network transmission may be established by using IEEE 802.11 protocols, but keeping in mind the cons of this type of network, which results in making any system slower, unreliable i.e. susceptible to interference and range is limited. There is a need to increase the range of wireless network; therefore multiple repeaters are to be added, hence increasing the overall cost. Generally paramedical staff with ECG training can give interpretation of prehospital ECGs without conveying to hospital and doctors [9] and instant medication can be done, whereas in case of lack of trained staff data has to be sent wirelessly. Here, a very simple scheme can be used [10] in which images of 2-lead ECG can be captured through camera phones shown in Figure 5 and can be sent over wireless messaging network to the cardiologist. Nowadays every person has camera mobile phones which cost very less and taking the advantage of availability to common man in this perspective, ECG waveforms can be transmitted to cardiologist for further processing and advice can be taken without establishing extra arrangements for wireless networks. Camera phones shorten the diagnostic time of Acute Coronary Syndrome[10].Online monitoring can also be done by transmitting small video clips of ECG waveforms in 3GPP file format of complete scan series of patients, using mobile phones with 3G MMS technology[10] or whatsapp technology. In addition to this, optional arrangements for Bluetooth, Zigbee or PC can also be considered into our system, but bluetooth is not optimal for a device operated on battery [16].

Fig. 3. Functional diagram of analog front end circuit [18]

B. Power Supply module The electric power to FPGA based EMS can be supplied by different types of sources like electricity, batteries & solar panels as shown in figure 4. Concept of solar homes which is used in Germany can be used for primary health centres in villages where electricity is not available for energising the medical systems. The system is battery operated & can be powered by solar panels. When batteries of the medical systems are exhausted, batteries of vehicles which are present around the site can also be used. So the proposed system can also be used at primary health centres.

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3) Digital Filter: 50Hz powerline interference in AFE circuit is filtered through adaptive canceller [14] which is integrated in the FPGA chip. 4) Clock generator module: It generates clocks for all other modules. Global clock pin C9 of FPGA provides input clock of 50MHz. III. EXPERIMENTAL RESULTS Figure 6 shows output data displayed on graphical LCD. The proposed FPGA-based medical system corroborates that the system has capablility of displaying the 2-channel ECG signal, heart rate on LCD & can indicate tachycardia & bradycardia on LEDs. For testing purpose, ECG input from MIT-BIH Arrhythmia database in .arb format has been taken from Agilent’s 33522A function generator & given to VINA & VINB input of onboard ADC and results are shown on digital storage oscilloscope, LCD & LEDS. The proposed system can also be used at night or adverse conditions.

Fig. 5 ECG image on camera phone

D.

FPGA system module

Xilinx’s Spartan 3E starter kit is chosen for the development of proposed medical system. FPGA-based designs offer too much flexibility in terms of reprogrammability & can be easily transformed to larger or newer FPGAs as the market demands [11]. Xilinx provides functional safety in Medical systems. FPGA chip acts as central microprocessor unit in FPGA and is designed on Verilog to realize ECG signal processing in real time. The FPGA chosen is a Xilinx: XC3S500E Spartan-3E. It has over 10,000 logic cells [12], x16 data interface, 64 MByte (512 Mbit) of DDR SDRAM, 100+ MHz. The package is a 320-pin FPGA. It’s clock is of 50 MHz crystal oscillator. It has up to 232 user-I/O pins[12], VGA display port, RS-232 ports [12], digilent 6-pin expansion connectors, four-output SPI-based Digital-to-Analog Converter , two-input, SPI-based Analog-to-Digital Converter with programmable-gain pre-amplifier, rotary-encoder with push-button shaft, 8-discrete LEDs, 4-slide switches, four pushbutton switches, SMA clock, eight-pin DIP socket. Following are important subsystems of FPGA: 1) Analog Capture circuit: FPGA Starter Kit board incorporates a two-channel analog capture circuit, it includes programmable scaling pre-amplifier and ADC. ADC converts raw ECG data received from analog front end (AFE) or function generator. Inverting amplifiers with programmable gain are provided with programmable preamplifiers. Amplifier scales the incoming voltage on voltage input pins. The LTC1407A-1 provides two ADCs. [12]. 2) VGA Display Port: It consists a VGA display port via a DB15[12] connector. In the proposed system port is directly connected to PC monitor or flat-panel LCDs for display of EKG waveforms.

Fig.6. The complete architecture of the proposed medical system (a)Subject with ECG signal Acquisition/simulator (b)FPGA based platform (c)ECG waveforms on LCD

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IV. LIMITATION Availability of wireless messaging network may be disrupted due to extreme weather conditions.

[1]Gao T, Massey T, Selavo L, Crawford D, Chen B, Lorincz K, Shnayder V, Hauenstein L, Dabiri F, Jeng J, Chanmugam A, White D, Sarrafzadehand M, W Matt. The advanced health and disaster aid network: a light-weight wireless medical system for triage. IEEE Trans. Biomed. Circuits Syst.2007; 1:203-216. [2] Why is India’s emergency healthcare system in tatters? (2012) [Online]. Available:http://www.thehealthsite.com/news/why-is-indias-emergencyhealthcare-system-in-tatters/

V. FUTURE SCOPE The proposed research presents a prototype & preliminary tests which validate our approach. Further future enhancements can be done by adding more sensors like temperature, EEG module, EMG module. x several types of sensors can be interfaced to ADC. x It can be extended up to 16 channels by using higher configurations so 12-lead ECG can also be analysed. x 8 patients having two lead-ECG or 16 patients having single lead-ECG can be analysed with the same system. According to Prime Minister of India while delivering his first address to Loksabha [17]. He said," we have agri-universities, but the transition from “lab to land” is not happening to the extent that it should be". Similarly in the case of healthcare systems also, whatever is present in labs after research it is not available in hospitals for patient care. Therefore present work is also an effort to take the research on the actual grounds i.e. for the wellbeing of mankind. Validation of the proposed medical research by doctors & clinical trials will be done in future.

[3]Emerging Healthcare: Taking off to the next level (2011) [online]. Available:http://modernmedicare.co.in/articles/emergency-healthcaretakingoff-to-the-next-level [4].Acute Coronary Syndrome (2013) [Online]. Available:http://www.mayoclinic.org/diseases-conditions/acute-coronarysyndrome/basics/definition/con-20033942 [5] Ramanujam P and Aschkenasy M. Identifying the Need for Pre-hospital and Emergency Care in the Developing World : A Case Study in Chennai, India. J. of The Assoc. of Physicians of India.2007;55:491-495. [6]Benson M, Koenig KL, and Schultz CH. Disaster triage: START, then SAVE—A new method of dynamic triage for victims of a catastrophic earthquake. Prehospital Disaster Med.1996;11:117–124. [7]Device Reliability Report. Xilinx, First Quarter 2014 [8] Tsai C; Hsieh ZH; Fang WC. A low-power low-noise CMOS analog frontend IC for portable brain-heart Monitoring applications. Life Science Systems and Applications Workshop (LiSSA), IEEE/NIH.2011;l: 43-46. [9] Implementation and Integration of Prehospital ECGs Into Systems of Care for Acute Coronary Syndrome. A Scientific Statement From the American Heart Association Circulation.2008; 118: 1066-1079.

VI. CONCLUSION The paper presents a scheme which improves healthcare with the help of FPGA based EMS. Pre-hospital cardiac care delay is minimized in patients. Therefore high speed medical system benefits directly in saving lives of patients. The possible achievement of the proposed system is that a few more lives can be saved and results in less number of people with morbidities due to calamities & emergencies. According to WHO, low and middle-income countries face significant challenges such as: limited financial resources, lack of available information, and lack of training [13]. The proposed system overcomes these problems as it is economic and even common man and volunteers present around natural calamity site can communicate to experts by sending ECG images with simple camera mobile phones. The proposed prototype is an initiative to attract attention of biomedical engineers & researchers in this direction and bring them together. After development of such type of proposed medical systems, trauma centres can be established easily in developing countries due to its cost effectiveness & feasibility.

[10] Waran V, Bahuri NFA , Narayanan V , Ganesan D & Kadir KAA. Video clip transfer of radiological images using a mobile telephone in emergency neurosurgical consultations (3G Multi-Media Messaging Service). British J. of Neurosurgery.2012;26:199–201. [11]. Using FPGAs to Render Graphics and Drive LCD Interfaces (2009) [Online]. Available: http://www.altera.com/literature/wp/wp-01100-graphiclcd-display.pdf [12]. Xilinx UG230 Spartan-3E FPGA Starter Kit Board User Guide (2011) [Online].Available:www.xilinx.com/support/documentation/boards_and_kits/ ug230.pdf [13] Medical Devices Save Lives (2013) [Online] Available: http://www.who.int/medical_devices/MD_Brochure_A4_2013.pdf?ua=1 [14] Ramos R, Lazaro AM, Rio JD and Olivar J.FPGA-Based Implementation of an Adaptive Canceller for 50/60-Hz Interference in Electrocardiography. IEEE Trans. Instrum. Meas.2007; 56: 2633-2640. [15] Chou CC, Fang WC, Huang H.A Novel Wireless Biomedical Monitoring System with Dedicated FPGA-based ECG Processor.16th IEEE Int. Symp. On Consumer Electronics.2012 [16] Ahola T, Korpinen P, Rakkola J, Ramo T, Salminen J and Savolainen J. Wearable FPGA Based Wireless Sensor Platform. 29th IEEE Annual International Conference of the IEEE EMBS.2001; 23-26.

ACKNOWLEDGEMENT Special thanks to all the support and encouragement which we received from the members of the Research Lab of the Instrumentation & Control Engineering Department, Netaji Subhash Institute of Technology (NSIT), New Delhi.

[17] Narendra Modi delivers first address to Lok Sabha, talks about Centre’s commitment to serve the poorest of the poor.(2014) [Online] Available: http://www.narendramodi.in/narendra-modi-delivers-first-address-to-loksabha-talks-about-centres-commitment-to-serve-the-poorest-of-the-poor/ [18] http://www.ti.com/product/ads1298.

REFERENCES

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