MIOT (Medical Internet of Things)
Survey Paper submitted by : Divya Dasararaju
Abstract – The advancement in microelectronics has fueled the development of compact wearable medical devices which can monitor vital health parameters and provide significant insights about a person’s health. The significance is much greater when such wearable devices are integrated with IOT and can track the vital health parameters over extended period and help in the prognosis of diseases. This emerging field is known as MIOT (Medical Internet of Things) or HIOT (Healthcare Internet of Things). A wearable health device can monitor and save data in its limited memory for a couple of days but once it is connected to Internet or Cloud services at a regular basis this device can help to accumulate years of data which can then, be used for a prognosis. This paper mainly discusses about MIOT and how a smart wearable device is controlled and managed through a mobile app with the help of Bluetooth.
Keywords – Wearable Devices, MIOT, Bluetooth, Health Monitoring, Vital Signs.
Emerging developments in wireless technologies and improvements in the on-body sensor design which can bring change in the conventional medical health care platform which will ultimately replace it with the Medical Wearable Devices mainly centered individual (1). With the constant modifications in our lifestyle and constantly increasing developments in the field of technology and mobility, it is becoming very hard to adapt a healthy lifestyle. It is important to keep a regular track of one’s health in the day to day basis. It is always wiser to be attentive to monitor our health habits. This kind of regular check can be achieved by monitoring Vital Health Parameters with the help of Wearable Devices. While the rapid developments in the field of health, the advancements caught the idea of the medical workers, researcher’s, customers. There is increasing novel ideas for wearable devices in hospitals and local families to monitor and track the vital health parameters (2).
As the world population is rising and chronic diseases are on the rise the medical industry is also rapidly developing high-tech advanced wearable devices that greatly improves patient outcomes and reduces healthcare costs. People become more health conscious and patients become health consumers seeking for better health and lifestyle changes which includes healthcare, fitness, rehabilitation. The conventional healthcare with hospitals is altering towards “patient/citizen” centered health and from diagnosis and treatment practice the attainment is put more in early detection and prevention. With the vast developments in sciences and technologies like Micro, Nano technologies (MNT), we tend to see more solutions to our health-related issues and new possibilities such as miniaturization, intelligence, low power consumption and at our affordable cost. As a result, these are consequences from continuous innovations and developments in technologies and great market demand for micro and nano technologies in medical applications like hearing aids, blood pressure devices, heart pacemakers and biochips. In “Patient/Citizen” health platform, it is essential to have necessary access to various kinds of health-related information e.g., patient/citizen up to date health record for an specific individual, monitoring and managing of individual health status through Vital Signs, which afterward transforms the data to health provider. With the previously stored patient data, it could advance health conditions in treatment, diagnosis, disease prevention and disease management (3).
Currently wearable devices are important part of any discussion related to IOT. With the emerging technology IOT (Internet of Things), which provided the possibility of monitoring and tracking human health environments with the help of Wearable Devices. A wearable medical device can be mentioned as non-invasive, self-determining system that completes a precise medical function such as monitoring or tracking the results. The “Wearable Device” is something that is connected directly to human body and has a necessary design technology to enable its prolonged use as wearable device. In other words, we can say that the device should be minimal size and weight such that it is easy to use and worn in comfort. Remote health care monitoring allows patient/citizen to stay at home rather than in expensive health care providers e.g., nursing homes, hospitals. This typical device is constructed around a central processing unit which in turn provide and monitor a degree of physiological tracking of data, the respective data and processing combined with the help of microelectronics, mechanical, electrical functions that involves high degree of intelligence and telemedicine functions. Like any other computer, these medical devices processes input mechanism, respective central processing unit and output mechanism. Firstly, the input mechanism deals with the gathering information about clinical and environmental though the direct data input by the user, physiological and other sensors. The main function of the central processing unit is to handle the real time input information to deliver the appropriate feedback. The feedback which is delivered by the central processing unit is thus can be directly accessed by the user in different forms that includes monitoring, decision support functions, alerting or it provides a control mechanism for other components of the system presenting support functions (5).
Wearable devices or wearable technology has grown to the very huge industry which serves many other markets and we can say this market is becoming a new source of big data, attracting many multinational companies and corporations which include the entire value chain. Source from IDTechEx predicts that these wearable devices are likely to reach about $150bn in 2026. Revenues are predicted to raise by 23% from 2018 until 2023 and to touch over $110bn by 2023 (6). As per new report from Tractica, medical healthcare wearables of worldwide shipments will gradually increase from 2.5million in 2016 to 97.6million in 2021. At the end of this period the market of global health care wearable devices will tend to $17.8billion in yearly revenue (7).
Fig 2. Shipments and Revenue for Wearable Medical Devices, World Markets: 2015-2021 (Source: Tractica) (7)
The term “Wearable” suggests that the support environment is either body or piece of clothing. In a border sense mostly commonly used medical equipment’s like eyeglasses, bandages, contact lenses can be obviously considered as wearable devices because they are wearable, and they provide respective medical function. In this context in particularly we deal with much more sophisticated products that integrate mechanical functions with microelectronics, computing capabilities and such medical functions that are currently performed by such devices include applications of health monitoring, long term medical aid and rehabilitation assistance. Most of the current devices depends on human intervention to record data processed later offline.
2. Evolution of Medical Wearable Devices
One of the main driving force behind the advancements of wearable devices is that medical field which is shifting from hospital to home care and subsequently to personal health care. Wearable devices provide the versatile means of medical monitoring and support, but the main functionality is based on the innovative technologies that are evolving now. With the advancements in wearable technologies, corresponding developments in microsensor technology, wireless communications and their fusion with clothes industry that enable wear ability leads to the developments in wearable devices. The first wearable technology was invented backed in the 13th century when eyeglasses were invented. Devices like transportable, wearable clocks were invented in the 16th century that became a status symbol in some parts of Europe until a wrist and pocketed watches were invented (8). It would be easy to monitor, and track steps has only just emerged in to our world, but it has been there for years. Wearable hearing aid which was invented back in 1938 marking one of the prominent steps towards the advancements of wearable devices in the field of Medical Industry. Then came the Vitatron C-series which was the world’s first digital pacemaker helped the clinicians to download patient information in just 18seconds (9).
The first medical wearable device was the Holter monitor which was invented back in 1960’s, used for recording ECG data which collects data in a wearable device and will be used in later stage. Late in 1990s telemedicine was innovative approach and it was mostly practiced by the health practitioners for the further consultation despite of place and time. The necessity of real time accessibility for the individuals who are monitored continuously led to the development of wearable devices that incorporate clinical data and monitoring functions with telemedicine with real time wireless telemetry. With the help of this technology the first devices were developed for U.S space program where NASA would continuously monitor its astronauts in space to analyze physiological behavior of astronauts in space. Then the invention of wearable battlefield computers which was useful to monitor soldier’s health and their ability to fight in the battle filed and manage military communications that was developed by the US army (10). Then came the more prominent inventions of monitoring soldiers pulse, oxygen level, blood pressure which will be used to determine soldiers condition. With the rapid developments in the field of science and medical fields, there is enormous type of wearable medical devices that are evolving commercially today. Amidst of 2010, wearable device technologies started to encompass with IEEE, IETF and other major Industry Standards such as most efficient wireless technology i.e., Bluetooth Technology which leads to other interfacing networks such as Wireless Body Area Network (WBAN) and Wireless Personal Area Network (WPAN) categories. Then Google launched its first Google Glass and released the same to the public for a starting price of $1500, this was an alarming period for the many companies to run into wearable market including Samsung (Galaxy Gear), Apple (iWatch), Sony (Smart Watch) and many others. The milestone started with the launch of Nike and Apple launch Nike+ iPod integrating with a sensor worn in a shoe that transmits running data like calories burned and the user exact distance traveled to the user iPod. These companies are focusing on a vast array of several types of health care wearable devices that includes fitness trackers, smartwatches, augmented reality game equipment (VR) and smart clothing. The more efficient activity trackers in 2008-2012 allowing users to track steps taken, calories burned, sleeping patterns, activity intensity, distance travelled, heart rate, ambient temperature and even monitor UV exposure. The devices are expanding with a rapid growth and with in 10-20 years we can see science fiction will appear in our real lives (11).
3. System Design: HIOT
The emerging prototype of Internet of things is mainly aimed on collecting and processing data all the time and everywhere. With the development of IoT enabling to use all type of objects with their basic functionalities for example in the field of medical care devices are being designed in such a way that patients are monitored to manage specific chronic conditions. Related with this idea medical internet of things is a new concept to create efficient health services and monitor the vital health parameters. Now-a-days lot of gadgets and sensors are used to collect data from various parts of the human body which is in contact and thereby collecting the respective data and developed. In recent years many applications have been developed around medical internet of things concepts to sense capabilities of things that play a vital role in determining and monitoring human health and behavior. There were many devices and applications which play a significant role in gathering data by means of wearable devices and that will integrate with mobile device users and thus enabling the vital health parameters for different purposes such as wellness monitoring, training and medical care (12).
Mobile devices are advanced enough, and the wearable devices were integrated to work with biomedical data and run health related applications.
Wearable devices for health monitoring systems consists of diverse types of miniature sensors that are wearable. These miniature sensors can measure vital parameters like blood pressure, oxygen level, heart rate, respiration rate, body and skin temperature. The obtained parameters are then transmitted via Bluetooth to the android mobile and from there to the prescribed medical center. The figure illustrates that a wearable medical system may incorporates wide variety of components that includes wearable materials, sensors, smart textiles, wireless communication modules, control and processing units, software algorithms for data extraction and retrieving. Health monitoring system consists of acquisition module, android mobile and health care provider, in which framework includes acquisition module, gateway which is categorized as smartphone, and the webserver i.e., health care provider in which data is transmitted via Internet of Things module.
Fig.3 Medical Internet of Things for Healthcare (13)
(Source: Medium Corporation)
Acquisition module consists of smart devices to monitor conventional parameters such as blood pressure, heart rate, body temperature, oxygen level etc. All the information from these devices is collected and transfers the data with the help of Bluetooth module to send results wirelessly. Bluetooth is a wireless technology industry specification for short range connectivity between fixed and portable devices (13).
4. Vital Signs Monitoring
Many wearable devices have been invented to monitor critical parameters in health care. Vital signs are measurements of basic body functions of human mainly blood pressure, pulse rate, body temperature, respiration rate. These vital signs can be measured and monitored in a medical setting at a medical emergency or at home or elsewhere (14). There have been many efforts in wearable devices to elaborate its functions in multi task vital signs monitoring. The four main Vital Signs normally monitored by health professionals are 1) Body Temperature 2) Blood Pressure 3) Heart Rate 4) Respiration Rate.
4.1.1 Body Temperature:
Body temperature gives an insight into the physiological state of an individual. Abnormal change in body temperature is a sign of fever or infection. On the other hand, the lower body temperature indicates low blood flow in the body because of the circulatory shock so the body temperature is considered as the first vital sign. While determining the body temperature the cause of measurement factor should be taken in to count as the body temperature changes determining on the measurement factor. For instance, consider at moderate room temperature (23c) wrist temperature is at 30c and the body core temperature is about 35c. Temperatures that are recorded are much less than the body core temperature because in any wearable method, the temperature sensors are normally places on the chest or arm. Devices like Thermistors, thermoelectric effects are used to measure the body temperature. Nevertheless, the most eminent method in wearable sensor is the Thermistor Configuration. The resistance of resistors depends on the temperature. Th ere are many important advances have been made in the field of wearable temperature sensing devices but there are still some obstacles disturbing the accurate temperature measurement to occur. Mostly thermistors manifest strain dependence which is not good for wearable sensing due to when we twist or flex, the sensor can modify the resistance of the respective thermistor. Like said every obstacle has a solution, there is approach utilizing small scale rigid thermistor which is embedded with stretchable and flexible matrix that is used bypass the strain dependence. With the help of this method flexible and stretchable matrix will give the compliance and the rigid thermistor will eventually have minimal influence by the induced strain. Skin temperature always has a strong connection and dependence on the environmental fluctuating temperatures. With the use of wearable sensor devices temperature measured in the indoor and the outdoor environments will shift 2-3c in the skin temperature. Also core temperatures tend to shift in between 1-2c throughout the day. The variations between the skin temperature and core temperature are not similar but even though it is possible to establish a connection between these two. The evaporation of sweat outcomes in minimizing the relationship between the skin temperature and core temperature and it will deprave the thermal contact between the sensor and the skin. For accurate core temperatures to render all these methods to be addressed.
4.1.2 Blood Pressure:
Blood pressure is very well-known term in our day to day life and is one of the most prominent factor in the general health condition of a person. The device that is used to measure the blood pressure is called as sphygmomanometers which has a pump attached to an inflatable cuff which is normally wrapped around the patient/person’s arm and the manometer which is attached to it is used to measure the pressure. At the beginning the cuff pressure is normally magnified above 200mm Hg breaking of the blood circulation to the person’s arm and then the pressure gradually decreases making the blood to erupt into the blood vessel at the high pressure of the pulse which is called as systolic pressure. The lowest pressure of the pulse is diastolic pressure where the pressure is reduced to a lower point such that making the blood to stop flowing. The blood pressure of normal healthy person lies in a range of 120/80(systolic/diastolic). This blood pressure can be measured with the help of sounds heard through a stethoscope. With the help of sphygmomanometers, it has become normal in clinical visits but this type of devices of more likely limited by their static setup and expensiveness which makes them to monitor continuously.
4.1.3 Heart Rate:
The main function of the human heart is to pump to oxygenated nutrients and blood to the whole parts of the body and discharge carbon dioxide and other wastes which are produced in the body. The process of pumping deoxygenated blood to the lungs and supplying newly oxygenated blood to the whole body though aorta is called cardiac cycle. The pulse or heart rate is expressed in terms of beats per minute (b.p.m) which is the frequency of cardiac cycles. Any change in mental or physical state of mind changes the pulse. Therefore, Heart rate is one of the most important vital sign to monitor mental and physical state of a person. The Heart rate can be measured normally from a stethoscope, radial artery at the wrist or from the carotid artery at the neck. To measure heart rate more accurately optical, electrical and strain sensors can be used. The sensors that are used in the wearable devices was used to measure and monitor the heart rate. Depending on the electrical, optical and pressure the heart rate can be measured very accurately. Sensing location is determined based on the sensing technique. For example, optical or pressure sensors are preferred on the wrist and similarly ECG electrodes are chosen over the pressure or optical sensors on the chest.
4.1.4 Respiration Rate:
Respiration Rate is another important vital sign due to without proper intake of oxygen and removal of carbon dioxide, the prescribed patient is at risk of death or critical health condition. Most importantly abnormal respiration rates are marks of disorders like asthma, sleep apnea, anemia and chronic pulmonary disease. Sensors can be implanted in numerous ways to the flow of breath or to the contraction and expansion of chest to measure Respiration Rate. There are many ways to convert contraction and expansion of lungs in to an electrical signal. Electrodes that are implanted on the body and the change in the resistivity between contraction and expansion between them reflects the change. Most of the wearable respiration sensors which are connected directly to the human body can sense the expand and contract with the help of lungs and that indicate some type of pressure sensing to the volume change. With the advancements in technology many new wearable pressure and strain sensors which utilizes the novel materials and main advantage of comfort and sensitivity (15).
4.2 Motion Trackers:
There are many devices which are useful in monitoring above mentioned vital parameters in our day to day life. Below are the four most popular wrist worn wearable devices – a) Fitbit Flex, b) Withings Pulse, c) Misfit Shine, d) Jawbone
Fig.5 (A-D) Popular Four Tracker Wearable Devices (16)
Fitbit Withings Misfit Jawbone
Dimensions(inch) 6.3*8.2 1.7*0.87*0.33 1.08*0.13*1.08 6.1*6.1
Weight(g) 16.4 8 9.4 19
Battery life (month) 4-6 6 3 4-6
Rechargeable Battery Yes Yes No yes
Changeable battery No No Yes No
Usable time per charge Up to 14days Up to 14days Up to 180days Up to 10days
Price in market ($) 100 100 95 150
Table 1. Characteristics of four Wearable Devices (16)
Human body movement can be measured with the help of various kind of motion trackers. These devices can motivate the person to daily during the workout time to perform and burn more calories and which provides this activity measured through a smartphone without any human calculation (16).
Fitbit Flex Counting of steps, quality of steps, small size, wrist worn
Withings Pulse Distance travelling, step counting, measuring heart rate, recording sleep time and measure of optimal sleep hours
Misfit Shine Step counting, calories burnt, distance travelled, tracking of sleep, hours of light too
Jaw Bone Step counting, distance travelled, calories burnt, eating habits, daily activities, tracking of sleeping hours
Table 2. Features of four Wearable Devices (16)
5.Transmission of Data
Bluetooth is common low power RF Communication Technology which has been used widely in most popular devices like fitness trackers, laptops and smartphones for short range communication. The best on-body wireless communication would be the IEEE 802.15.1, Bluetooth which is widely used in WPAN wireless personal area network. The vital sign data which is synchronized in the wearable device is transferred to the smartphone with the most efficient wireless technology i.e., Bluetooth. The Vital Signs Monitoring data can measure the continuous data for some real time every day and which is prescribed to monitor blood pressure, heart rate, body temperature, distance travelled, calories burned, active sleep hours, the devices data package encryption and then transferred to the cloud platform with the help of Bluetooth. The cloud platform will decode, process the data and save the vital signs data after it receives after these vital signs data with a Bluetooth as a medium (17). This WPANs cover the extend away from the body i.e., off-body communications. On other side, Wireless Body Area Networks which covers the immediate contact area of the body also known as intra-body communications. The very well know example for Bluetooth Usage in WBANs are the transmission of voice data between cell phone and head set. Many Bluetooth enabled devices function at the unlicensed scientific, Industrial, medical band around 2.45HGz which is further divided in to 79 channels with 1Mbps data rate. Frequency hopping spread spectrum technique is used for minimizing the fading and interference. The other technique called The Gaussian frequency shift keying which is effective in transmitting data in a range of two to ten meters. Bluetooth devices can form a piconet which is star topology network used for communicating with seven slave devices with help of master device which is connected to it. Bluetooth offers a low power method like body worn sensors for very low requirement power options. When comparing to other technologies high power transmission is a limitation for Bluetooth Technology and it is vulnerability to security concerns because of ad-hoc networking (18).
5.2 Remote Monitoring System:
The remote health care monitoring is a kind of ambulatory health platform which involves the body sensors that are implanted in the wearable deices to measure and monitor temperature, blood pressure, heart rate, distance travelled, calories burned and sleep hours and thereafter sending them to a real time remote server which carries the further analysis. Monitoring of patient’s health condition using wireless medium of networks is really a ground-breaking idea an also helps the patients to predict patient’s health condition based on their Vital Signs and medical history (19). When the mobile phone is in the network and then the wearable device software will start to upload the stored data, which enables the system to be in data integrity and validity. The cloud platform server ensures the data validity and the data integrity. The data that is aggregated should be transferred to the cloud for long term storage. To address privacy patterns, the data must be encrypted before sending transmission. A lot of data is being measured and generated about an individual’s health. Most significantly, it proposals persistent monitoring of patient’s health condition as wireless sensor medium transfer the data to the remote server with the help of Bluetooth which is widely available (20).
Wearable medical devices are gaining popularity in in different fields like sports to fitness in real time monitoring of heath. The IoT is promising emerging technology that comprises of interconnected devices. These interconnected network devices offer faster, better and cheaper customer satisfying applications in health care sector. The main aim of this paper is to give a comprehensive overview regarding Vital Signs and Motion Trackers are most significant parameters mostly focused on Temperature, Blood Pressure, Heart rate and Respiration Rate in the health monitoring therefore to gain the complete knowledge off health monitoring all the above-mentioned parameters were studied. The data that is collected from the device is transmitted to the android mobile through Bluetooth Technology and then the data is analyzed, transmitted to the cloud for storage in real time. The data that is stored in the cloud can be view by users and then keep track of their health habits for future.
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