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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Emerging Technology Trends on the Smart Industry and the Internet of Things, January</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>IoT-based Pain Monitoring and Management System</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Fouad Jameel Ibrahim Alazzawi</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Marwa Azzawi</string-name>
          <email>marwa.azzawi@yahoo.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Madiha Fouad Jameel</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Yurii Khlaponin</string-name>
          <email>y.khlaponin@gmail.com</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Biomedical Engineering Department, Al-Nahrain University</institution>
          ,
          <addr-line>Baghdad</addr-line>
          ,
          <country country="IQ">Iraq</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Computer Engineering Department, Al-Rafidain University college</institution>
          ,
          <addr-line>Baghdad</addr-line>
          ,
          <country country="IQ">Iraq</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Department of Dentistry, Al-Rafidain University college</institution>
          ,
          <addr-line>Baghdad</addr-line>
          ,
          <country country="IQ">Iraq</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Kyiv National University of Construction and Architecture</institution>
          ,
          <addr-line>Povitriflotskyi Ave., 31, 03037, Kyiv</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2022</year>
      </pub-date>
      <volume>19</volume>
      <issue>2022</issue>
      <fpage>124</fpage>
      <lpage>131</lpage>
      <abstract>
        <p>Patient suffering from pain is in need for an immediate medical intervention, however in some cases self-pain assessment is not available due to unconsciousness or prone to errors due to observer's biases. Therefore, automated pain assessment and management is needed. The internet of things (IoT) revolution along with biosensor technology could be convenient for pain assessment and management application. Therefore, this paper is a mini-survey of the literatures in this field published in six years (2016-2021) was conducted in three online databases. Hundreds of papers were found, however after title, abstracta and contents screening only 13 papers were included. This paper is aimed to review the papers that suggest a pain assessment model in a IoT philosophy, in order to summarize the present work and propose new suggestions for future work. Research with different pain levels, in a bigger and real patient population with different diseases were suggested in the conclusion for future work.</p>
      </abstract>
      <kwd-group>
        <kwd>Keywords1</kwd>
        <kwd>Internet of Things</kwd>
        <kwd>pain monitoring</kwd>
        <kwd>pain management</kwd>
        <kwd>biosensor</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Pain is the fifth vital sign besides the temperature, pulse rate, respiration rate and blood pressure.
Furthermore, it is one of the most warning signs for seeking medical consideration [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Mostly, pain could
significantly contribute the quality of life and cause psychological disturbance including depression,
sleeping disorder, anxiety and fatigue which lead to physiological problems. Therefore, adequate
assessment of pain is essential for precise determining of appropriate treatment [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
      <p>
        Commonly, pain assessment is done through a self-report or different observational pain scales such as
Numeric rating scale (NRS) [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] and Visual Analogue Scale for Pain (VAS) [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. However, self-reporting
method could be prone to different types of errors, including the subjective biases of the observer and
patient’s ability to express the amount of perceived pain. Moreover, under special circumstance as in the
patients who are noncommunicative it is not possible to assess the amount of pain. On the other hand,
accurate pain management relies on continuous and precise pain assessment, however, it is impractical to
continuously monitor pain by humans. Furthermore, overdosing of pain-killers could be a life-threatening
problem that may cause a prolonged sedation or hepatic injury [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
      </p>
      <p>2022 Copyright for this paper by its authors.</p>
      <p>
        Therefore, researchers through the last decade tried to identify the alter of different physiological signals
as a consequence of pain suffering, including electromyography (EMG) [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], electrocardiography (ECG)
[
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], electroencephalography (EEG) [8] and photoplethysmography (PPG) [9] in real-time monitoring. ECG
are the process of measuring the small electrical fluctuation produced by the cardiac muscle and it gives as
indication about blood flow, while EEG evaluated brain’s electrical activity and the EMG tracks the
electrical activity of the muscles. Moreover, PPG signal measures blood volume change using irradiation
light applied non-invasively to peripheral body sites. All these signals show alteration and abnormalities
during suffering from pain. Galvanic Skin Response (GSR) is another characteristic that exhibits fluctuation
in the signal during pain due to change of skin conductance.
      </p>
      <p>In the last years, physiological parameters such as heartbeat is not assessed through a clinical and
physical examination. Today, a smartwatch can identify heartbeat and the observed data is sent to a cloud
through a wireless network to be observed by physician, hospital, and other stake holders. Furthermore,
data is stored in a digital form and analyzed for machine deep learning (ML) purposes. All the previous
process is done through what is known as the internet of things (IoT) which connect computer and
healthcare provider together to make our life easier [10]. Figure 1 illustrates the lifecycle of the IoT assisted
wearable sensor system in health care.
In this mini-review, the aim is to overview, consolidate and summarize the work that has been done over
the last six years to automatically assess pain from different biomedical signals including EEG, EMG, PPG
and GSR, to identify the challenges and determine the direction of future researches. In this paper, a survey
of “IoT” and “pain” database is done in three different online databases. Then a focused reading, studying
and categorization followed by concluding is performed and many papers were excluded in this stage
according to the methodology described in the second section of this paper. All the results of the survey of
the databases containing IoT using in paint monitoring and controlling were discussed and presented in
section three. Section four concludes the paper and discusses the future opportunities of such work.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Methodology</title>
      <p>Papers in this mini-review were collected by searching three online database, including google scholar,
ScienceDirect and IEEE Xplore. All the research articles, review articles, book chapters, conference papers
were included in the research, however, the review articles were excluded during results analysis and
discussion. The research was conducted during December 2021 and is limited to six years period, which
is between 2016 and 2021. Furthermore, the search was limited to English language papers and the search
keywords was ‘IoT’ OR ‘Internet of Things’ AND ‘pain assessment’ OR ‘pain monitoring’.</p>
      <p>The inclusion criteria in this mini-review were based on 1) any scientific paper that describe IoT-based
solution for pain management, 2) all included papers should mentioned the word ‘internet of things’ or
‘IoT’ or any technique used in IoT, 3) review articles, mini-review articles, papers with only an abstract
and case reports were excluded.</p>
      <p>The papers were collected for review and the following points were focused on during reading:
 The paper is about pain detection or assessment not targeted emotions, mental health, happiness or
sadness and stress.
 The paper is targeted a patient with pain or a disease that causes pain not affecting the healthy
person with a painful stimulus like heat to cause pain and assess that pain accordingly.
 The physiological parameters detected, or the biosensor used, on the other hand the IoT technology
used in the work.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Results and Discussion</title>
      <p>Three databases were searched for suitable papers depending on the review methodology of this
minireview. Hundreds of papers were found then they were filtered after reading the abstract. For instance, in
the ScienceDirect database 274 papers were found in the period between 2017–2021, and they are
distributed as per Fig. 1. As per figure the subject started to gain interest more after 2019.</p>
      <p>However, after reading the abstract many papers have been excluded due to many criteria, for instance
miss understanding between pain and mental health and emotions which is not an indication of pain
specifically. Moreover, papers that were not about medical application of pain assessment were excluded
too.</p>
      <p>The over all papers after all the exclusion were 12 papers as listed according to the year of publication
in Table 1. Physiological parameter or biosensor used, medical problem targeted, IoT-based technology
used and wither the paper worked on pain assessment or pain management or both were mentioned in
Table 1.</p>
      <p>As per Table 1 the “pain assessment” and “IoT” subject work started to increase after 2019. For instance,
in 2020 (6/12) papers in pain assessment and IoT technology in medical application were published.
Furthermore, (7/12) of the papers were on patients after surgeries especially orthopedic ones like joint
replacement surgeries and in intensive care unit. Mostly, the reason behind that is poorly controlled
postoperative pain correlated with prolonged duration of recovery, impairment of daily life and eventually
increase morbidity, according to reference [24]. Therefore, continuous assessment and control of pain
through applying of drug analgesia according to pain intensity is a cutting-edge subject that would cost
lower health-care expenses in addition to adequate treatment and recovery. Furthermore, few papers were
about specific disease and pain caused by them like tension-type headache (TTH) and Sickle cell disease.
One paper was about remote rehabilitation of elbow and control of pain due excessive movement, through
a feedback process. Fig. 3 shows an overview of the control architecture.
parameter or biosensor, medical problem, IoT-based technology and Pain
monitoring and
management are mentioned
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes</p>
      <p>Pain
monitoring</p>
      <p>Pain
management</p>
      <p>Pain
monitoring</p>
      <p>Pain
management</p>
      <p>No
No
No
No
No
No
Yes
No
No
No</p>
      <p>Yes
(Biofeedback
therapy)</p>
      <p>Yes
(Drug analgesia)</p>
      <p>Ref.
[12]
[13]
[14]
Ref.
[15]
[16]
[17]
[18]
[19]
[20]
[21]
[22]
[23]</p>
      <p>Year of
publication</p>
      <p>Year of
publication
2016
2018
2019
2020
2020
2020
2020
2020
2020
2021
2021
2021</p>
      <p>Physiological
Parameter or</p>
      <p>biosensor
Facial expression
using surface EMG
Facial expression
using surface EMG
PPG depending on
pulse counting</p>
      <p>analysis
Physiological
Parameter or</p>
      <p>biosensor
High-density
painevoked EEG</p>
      <p>potential
Clinical notes</p>
      <p>Peripheral blood
flow and skin ability</p>
      <p>to conduct
electricity using
PPG and GSR
GSR, EMG and</p>
      <p>EEG signals</p>
      <p>EMG signal
Force and sweat</p>
      <p>sensor
Electrodermal
activity of GSR
PPG spectrogram
Heart rate and body
temperature</p>
      <p>Medical problem
Patient with pain
Intensive care
unit patients
Post operative</p>
      <p>patient
Medical problem
Patient with pain</p>
      <p>Sickle cell
disease patient
Patient with pain</p>
      <p>TTH
Remote elbow
rehabilitation
Indication of
labor pain
Post-operative</p>
      <p>patient
Post-operative
pain in conscious</p>
      <p>patient
Post-operative
bone and joint
replacement
surgery</p>
      <p>IoT-based</p>
      <p>Technology
Wi-Fi with a cloud</p>
      <p>serve</p>
      <p>Mobile web
application with</p>
      <p>cloud server
A model builds on
multiple logistic
regression
IoT-based</p>
      <p>Technology
Auto encoder model
based on CNN1
Four binary ML2
classifier</p>
      <p>Several
communication
protocol for IoT
FOG computing</p>
      <p>Fuzzy logic
GSM through cloud</p>
      <p>server
ML algorithms</p>
      <p>CNN
System based on</p>
      <p>NOA3</p>
      <p>Facial expression using a surface EMG biosensor for pain assessment was one of the technique used to
quantify the pain, however no works were found after 2018. The reasons behind this is claimed to be that
this technique faces several challenges related to data acquisition and development, on the other hand pain
assessment system should be capable to be adapted according to patient facial morphology and texture [25].
However, Yang et al. [13] have designed a wearable mask based on surface EMG signal for continuous
pain assessment as per Fig. 4.</p>
      <p>Furthermore, a paper was about labor pain assessment using a belt around the belly that sense the sweat
using a GSR sensor and the force generated by delivery contractions. Biosensors used in papers were
equally used in (4/12) for GSR, EMG and PPG, however EEG was the less commonly used due the artifacts
and requirement of high data transmission rate and large storage capacity [17].</p>
    </sec>
    <sec id="sec-4">
      <title>4. Conclusions</title>
      <p>As a conclusion, pain monitoring and control is a worthy and wide-range research topic. The studies
mentioned in this mini-review are poor in many aspect, for instance, number of applied patients, scale of
pain level and connection with medication management system. However, several biosensors and IoT
technologies have been covered by the researchers, but the effective application of the automated pain
assessment is yet to come.</p>
      <p>This mini-review discussed a total of 12 paper in pain assessment ant management using IoT-technology
in many medical applications. Future studies can be more precise in the medical application they targeted,
for instance, considering cancer patients who suffers from sever pains and in need for medication control,
also patients with high rate of heart stroke who suffers from severe chest pain and in need for immediate
medical intervention.</p>
      <p>Furthermore, future studies concentration on Fog networking, that can support the big data structure and
large cloud system with large geographical distribution are expected to further improve performance.</p>
    </sec>
    <sec id="sec-5">
      <title>5. References</title>
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