Recently, remote healthcare systems have received increasing attention in the last decade, explaining why intelligent systems with physiology signal monitoring for e-health care are an emerging area of development. Therefore, this study adopts a system which includes continuous collection and evaluation of multiple vital signs, long-term healthcare, and a cellular connection to a medical center in emergency case and it transfers all acquired raw data by the internet in normal case. The proposed system can continuously acquire four different physiological signs, for example, ECG, SpO2, temperature, and blood pressure and further relayed them to an intelligent data analysis scheme to diagnose abnormal pulses for exploring potential chronic diseases. The proposed system also has a friendly web-based interface for medical staff to observe immediate pulse signals for remote treatment. Once abnormal event happened or the request to real-time display vital signs is confirmed, all physiological signs will be immediately transmitted to remote medical server through both cellular networks and internet. Also data can be transmitted to a family member’s mobile phone or doctor’s phone through GPRS. A prototype of such system has been successfully developed and implemented, which will offer high standard of healthcare with a major reduction in cost for our society.
A healthcare system in the last decade was made possible due to the recent advances in wireless and network technologies, linked with recent advances in nanotechnologies and ubiquitous computing systems. The term telemedicine refers to the utilization of telecommunication technology for medical diagnosis, treatment, and patient care [
Main components of telemedicine system.
The biosignal sensors are responsible for acquiring the physiological data (patient’s vital signs) and transmitting it to the signal processing unit. Several studies are made focusing only on designing these sensors to be tiny in size [
To improve the mobility of the doctor, the global system for mobile (GSM) communication mobile telephony network was used for connecting the server [
Set of telemedicine studies along with aspects which each study concerns.
Reference |
Biosignal sensors | Communication technology | Medical algorithm | Comments | |
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GSM/GPRS | Internet | ||||
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ECG, BP, HR |
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WSN, type of localization method for patients and an energy efficient transmission strategy, video streaming. | |
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HR, SPO2, |
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Implement a prototype of telemedicine system based on wireless technology using GSM and GPS. | ||
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Weight, activity, |
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Android application for monitoring and using Bluetooth enabled sensors. | |
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BP, HR, TEMP. |
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Design of sensors to reduce power consumption using VLSI and FPGA. | |
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ECG, HR, SPO2, |
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Wearable belt; high quality and flexible modules for signal conditioning are designed and assembled together. | ||
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ECG, BP, HR |
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Small rang RF transmission, smart wearable vest, deriving BP and HR from ECG. | |
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ECG |
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QRS detection algorithm, extraction of heart rate variability, implemented in the PDA and GPS. | |
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ECG |
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A real-time ECG classification algorithm, GPS, and a real-time R wave detection algorithm. |
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Pulse signal |
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Intelligent data analysis scheme to diagnose abnormal pulses for exploring potential chronic diseases. | |
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ECG, HR, SPO2, |
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Vital signals are acquired from the monitor using the RS232 interface and transmitted through the internet. | ||
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ECG, BP, HR |
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Commercial monitors are used for the acquisition of biosignals and Huffman algorithm for ECG signal compression, GSM, GPRS, POTS, or satellite. |
In this paper, we propose a wireless telemedicine system which integrates sensor unit, processing unit, and communication unit in one chip bounded to patient’s body called mobile-care unit. This will improve patient’s mobility and will not affect active daily life during monitoring. To lower the cost of using GPRS network, only abnormal readings are transmitted so the proposed system operates in two modes, store-and-forward mode and real-time mode. In store-and-forward mode the care unit records and transmits patient’s vital signs to the server through the internet. When an abnormal heartbeat that the doctor concerns is detected, the care unit transmits it to the server via GPRS network in real-time. The doctor at the server side could communicate with the patient also by using SMS if necessary. The proposed system also has a friendly web-based interface for medical staff to observe immediate vital signs for remote treatment which will give more mobility for medical staff. The remainder of this paper is organized as follows. The system is described in Section
This section describes in detail the system design based on physiological sensor, signal processing, embedded system, and wireless communication and World Wide Web technologies. Figure
The architecture of the proposed system.
The aim of this study is to design and implement a telemedicine system with intelligent data analysis based on physiological sensors, embedded system, wireless communication, and World Wide Web for vital signs monitoring, patient diagnosis, and home care. Architecture of the proposed system is shown in Figure Mobile-care unit: it could be bound to patient’s body and could acquire real-time or periodical vital signs information without affecting their normal activities. Then an intelligent data analysis scheme is applied to identify abnormal pulses and transmits these data to the remote server by wireless communication through either internet in store-and-forward mode for normal case or cellular networks in real-time mode for abnormal case. The transmission of patient data in real-time mode can also be operated manually. Whenever the user feels uncomfortable, he can transfer his current vital signs to the management unit for advice or a checkup. By this way, the cost for using the GPRS network is lowered because only abnormal signals are transmitted. For possible long-term store-and-forward mode, the raw data can be stored in the extended secure digital flash memory contained in the mobile-care unit. The remote server: it stores the received vital signs in a human physiology database and displays the physiology signals to the medical personnel through application program for diagnosis. Also, it enables remote access for caregivers and physicians to obtain vital signs through web-based interface over internet to monitor these data on their pervasive devices. After examining the vital signs data, the doctor can send a feedback MMS message to the user. The message may contain medical advice and/or a list of control commands to the mobile-care device for resending the abnormal case’s vital signs data. Also remote server may alarm family member in abnormal case and call emergency service to transport patient to nearest medical center. Pervasive devices: pervasive devices include laptop, personal digital assistant (PDA), and mobile phone. Through these terminal devices family members or doctors can acquire abundant information about the healthcare recipients anywhere and at any time.
This section details the system components of the proposed emergency telemedicine system for patient monitoring and diagnosis.
In the proposed system the mobile-care unit was designed to be portable and lightweight which means it is easy to carry and easy to use making patients do nothing. The mobile-care unit consists mainly of three modules. These are mainly vital-sign signals acquisition module, data control and processing module (MCU), and data communication module. Thus it can collect critical biosignals, including three-lead ECG, HR, blood pressure, and SpO2 which are vital signs. Also, it may evaluate patient status and trends in patient’s medical condition and it may generate emergency alert if the patient’s condition is critical. Moreover, it should support wireless communication and be compatible with global positioning information system to locate the patient position for emergency help. Figure
Mobile-care unit.
The ECG signals are typically 1mV peak-to-peak; an amplification of 300 is necessary to render this signal usable for heart rate detection and realizing a clean morphological reproduction. A differential amplifier with gain of 20 avoids the noises overriding the ECG signals; this is achieved by an instrumentation amplifier (INA321EA), CMRR of 100 dB, and at the end an operational amplifier (Analog AD8625) is used to amplify the signal with a gain of 15. The ECG signals are restricted in bandwidth of 0.5–100 Hz using second order Butterworth high pass and low pass filters after the first stages of amplification. The power line interference in the ECG signal is filtered by a 50 Hz notch filter, which is user selectable to avoid loss of 50 Hz component of the ECG signals. Then the ECG signal is fed to the analog input of processing unit for digitizing and analysis. Figure
Block diagram of ECG acquisition hardware.
(a) Temperature sensor. (b) Signal conditioning circuit.
Specification of various physiological parameters monitored.
Physiological parameter | Specifications | Typical values for average healthy person |
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ECG | Frequency: 0.5 HZ–100 HZ |
R-WAVE amplitude: >4.5 mv |
Heart rate (HR) | 40–220 beats per minute | 60–100 beats/minute |
Body temperature | 32°C–40°C | About 37.5°C |
Blood pressure | Systolic: 50–300 mmHg |
Systolic: less than 120 mmHg |
Blood oxygenation (SpO2) | Measurement range: 70–100% | Around 94% to 99% |
Respiratory rate | 2–50 breath/min. | Adults: 12–24 breaths per minute |
SpO2/HR sensor.
Architecture of microcontroller.
We can summarize the main functions of MCU in the proposed system as follows. It receives and digitizes the signals acquired from vital sign sensors. It controls the operation of all connected modules as shown in Figure It processes the received signals using different sorts of processing techniques and algorithms. It sets up a connection with the remote server and transmits to it the analysis results and raw data using communication techniques. It stores analysis results and raw data to flash memory.
Functions of MCU.
Sensor and module initialization component: it is in charge of starting, initializing, and configuring the medical care unit. Vital signs perception component: it acquires the values of vital signs from sensor nodes. Vital signs processing component: it realizes data conversion and processing and carries out patient diagnosis by determining the health status of patient. Information transmission component: data exchange between mobile-care unit and server is realized with the help of this component. Information receiving component: it helps the node to receive the controlling or inquiring requests from the server. Exception notification component: when the abnormal sensing information appears, it sends a message to the server immediately and sends out the alarm as soon as possible.
Work flow about mobile-care unit.
(a) ENC28J60 Ethernet module and (b) Sim900 GSM/GPRS module.
In the application of telemedicine, the medical information usually needs to be distributed among medical doctors and display, archival, and analysis devices. Therefore, the remote server unit is developed with the purpose of receiving, storing, and distributing the vital sign data from patients. The server is composed of presentation tier, web tier, and database tier. A multitier architecture allows for separation of concerns where any tier in the system can be expanded and updated with minimal or no effect on the client tiers. The following subsections discuss the three tiers further.
Access constraints are applied all the time based on the authorized user registered in the database. It includes lists of patients and personal information about patients. It displays patients’ vital signals and sets thresholds for each measurable parameter. It alerts healthcare providers in abnormal cases. It adds new patient, new consultation, and drug prescription. It shows past medical records for all patients including diseases, past surgeries, clinical findings, past medication, allergies, and images. It provides search for all registered patients by patient’s ID or patient’s name. It shows notations (patient experience) while taking measurements. It sends messages including instructions for patients and drug prescription. Sensor data will be automatically reloaded at predefined time intervals to keep the view updated.
Screen shots of the developed software are shown in Figures
Screen shot of the developed interface main page.
Add new patient screen shot.
Displaying patient’s vital signs.
User authentication page.
Displaying patient’s vital signs.
store, retrieve, and update patient’s record including his/her medical personnel’s contact information and other details; store and retrieve the received physiological sensor data transmitted by medical care unit; store, retrieve, and update patient’s consultations and drug prescriptions; store and retrieve patient’s notation during sessions; store, retrieve, and update registered doctors, physicians, and nurses; store, retrieve, and update the ECG data, record time, location of the R wave, and estimated ECG beat type.
Figure
Screen shot for how to search.
Web tier in the remote server is designed to allow remote user to acquire abundant information about the healthcare recipients anywhere and at any time using pervasive devices such as laptop, PDA, and mobile phone. Finally we can say that the proposed system can operate in the following three situations. Time-based connection: all data needed by the remote caregivers or specialists should be uploaded. Data compression is essential to limit the upload time. In this situation the remote caregiver should determine time schedule for uploading all patient data to remote server. The time schedule is stored in the mobile-care unit so it will upload data according to this time schedule. Emergency connection: to lower the cost of using GSM/GPRS network we develop algorithm which detects abnormal heartbeats. So during sensor monitoring, if the mobile-care unit detects an abnormal condition it sends the collected data to the remote server in order to receive clinical assessment and treatment planning. (Event awareness) connection on demand: the mobile-care unit uploads the amount of data requested by the remote caregivers or specialists to monitor the health status of the patient.
This paper proposes the design and implementation of a wireless telemedicine system, in which all physiological vital signs are transmitted to remote medical server through both cellular networks in emergency case and internet in normal case for long-term monitoring. By this, the cost of using GSM/GPRS network is reduced as only abnormal cases will be transmitted through cellular network. Also the proposed system presents friendly web-based interface for medical staff to observe immediate vital signs for remote treatment. Comparing this system with other systems which are mentioned in the introduction [
In the future, a lot of work could be done in the three main aspects of telemedicine systems to enhance the healthcare services. The three main aspects are type of sensors, signal processing algorithms, and data communication technology. In the sensor layer wireless sensor network of wearable noninvasive sensor units can be designed. Fabrication of sensors can be improved to obtain small size and low power sensors to improve patient’s mobility and prolong network lifetime. Also we can increase the number of transmitted vital signs to have a complete picture of patient’s case. For more improvement in telemedicine systems, many medical algorithms can be developed to help in patient diagnosis and early detection of cardiovascular diseases and real-time analysis of vital signs can be performed in the place where the vital signs are acquired. The latest achievement on a smart phone market provided an opportunity to integrate smart phones in telemedicine systems. For example, android based mobile phones patient monitoring application could be developed which allows doctors to monitor the health status of a patient using the easy to understand user interface (UI). This application also provides alerts, reminders, and emergency notifications for vital measurements to help doctors to take timely decisions in emergency situations. Finally for data communication technologies, in many countries, 3G mobile networks like the UMTS are currently installed and operating, which provide bandwidth up to 2 Mbps maximum (typically hundreds of kbps) [
The authors declare that they have no conflict of interests regarding the publication of this paper.