WSN for Healthcare

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March 2009

2009 ZigBee Alliance. All rights reserved. www.zigbee.or

ZigBee Wireless SensorApplications for Health,Wellness and Fitness


2/15 2009 ZigBee Alliance. All rights reserved. www.zigbee.or 2009 ZigBee Alliance. All rights reserved. www.zigbee.or

ZigBee Wireless Sensor Applications for Health, Wellness and Fitness - March 2009

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Foreword

Since its inception, the ZigBee Alliance has worked with a singular ocus: create a muchneeded global wireless language capable o giving voices to the myriad o everydaydevices which surround us as we go about our daily lives. This ocus has been aimed at the

little devices, o ten overlooked in an IT centric world, such as light switches, thermostats,electricity meters, remote controls as well as more complex sensor devices oundabundantly in the health care, commercial building and industrial automation sectors. Asa result, ZigBee Alliance members have created a wireless standard o ering extraordinarycontrol, expandability, security, ease-o -use and the ability to use ZigBee technology in anycountry around the world.

Today, organizations use ZigBee to e ectively deliver solutions or a variety o areasincluding consumer electronic device control, energy management and e ciency, homeand commercial building automation as well as industrial plant management. With thiscomprehensive set o attributes, the nonpro t, open membership and volunteer drivenAlliance has become a thriving ecosystem o more than 300 members. As an ecosystem,the Alliance o ers everything prospective product and service companies need to developZigBee products and services and bene t rom the Alliances competitive and stable supplychain.

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Executive Summary

The prospects o intervening to prevent deathin developing countries have never been better,said Dr. Gro Harlem Brundtland 1 . However theseimproved prospects come with a price tag. Healthcare costs (both economic and human) are sharplyrising in all regions o the world, not only in thedeveloped world. Several infuential actors are welldocumented as causes o this phenomenon; moresophisticated treatments employing advancedand costly technologies, longer li e spans withresulting increases in elderly population, rising costs

or energy, natural resources, and overall cost o living, increased living standards that can lead to anincrease o prosperity diseases like obesity, diabetes

and cardiovascular diseases.

ZigBee technology can be used today to beginachieving the vision o Dr. Brundtland. ZigBee is anAssistive Technology that can be used anywherein the world. It is designed with simplicity in mind,making it easy or people to use and allowing themto maintain their independence and mobility. It isalso extremely e cient in its use o power, and as aresult, capable o running on common batteries oryears.

New Assistive Technologies in Health Care based onwidely accepted standards, like ZigBee, will play animportant role in slowing down the sharp increaseo health costs. Medical devices based on the ZigBeestandard acilitate the reduction o costs associatedwith the development and manu acturing o new medical devices. Standards o er enormouseconomy o scale bene ts or components, whileo ering an unprecedented ability to simpli y the

control and monitoring o patients and unctions inhospitals, elderly care acilities and even homes.

The ZigBee Alliance is an association o companiesworking together to enable reliable, cost-e ective,low-power, wirelessly networked monitoring and

1 World Health Organization http://www.who.int/in -pr-2000/en/pr2000-78.

html

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control products based on an open global standard.Promoter member companies include Ember,Freescale, Huawei, Itron, Landis+Gyr, Philips, ReliantEnergy, Samsung, Schneider Electric, Siemens,STMicroelectronics, Tendril and Texas Instruments.

The goal o the ZigBee Alliance is to provide theconsumer with ultimate fexibility, mobility andease o use by building wireless intelligenceand capabilities into everyday devices. ZigBeetechnology is being embedded in a wide rangeo products and applications across medical,commercial, consumer, industrial and governmentmarkets worldwide. For the rst time, organizationshave a simple, reliable, low-cost and low-powerstandards-based wireless technology optimized or

the unique needs o remote monitoring and controlapplications.

ZigBee will play an important role in the adoption o Assistive Technology by enabling wireless low-powercommunication between devices and servicesthat oster sa e, healthy and independent livingconditions or the disabled or elderly. In additionto Assistive Technology, ZigBee applications in thehealth and tness domains can address several othermarket segments and needs. The ollowing analysis

ocuses on applications o ZigBee technology orchronic disease monitoring, personal wellnessmonitoring and personal tness monitoring.


4/15 2009 ZigBee Alliance. All rights reserved. www.zigbee.or 2009 ZigBee Alliance. All rights reserved. www.zigbee.or4

Table of ContentsIntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Overview o ZigBee Monitoring and Sensor Solutions . . . . . . . . . . . . 5

Market Opportunities - Economic Drive . . . . . . . . . . . . . . . . . . . . . . . . . 7

Future Market Projections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Current State o the Market . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Applications o Wireless Sensors or Better Health Care . . . . . . . . . . . 8

1. Chronic Disease Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Episodic Patient Monitoring Scenario . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Continuous Patient Monitoring Scenario . . . . . . . . . . . . . . . . . . . . . . 10

Patient Alarm Monitoring Scenario . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

2. Personal Wellness Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Senior Activity Monitoring Scenario . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Sa ety Monitoring Scenario . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

3. Personal Fitness Monitoring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Monitoring and Tracking Fitness Level Scenario . . . . . . . . . . . . . . . . 13

Personalized Fitness Schedule Scenario . . . . . . . . . . . . . . . . . . . . . . . 13

Example Products Applicable or Health Care . . . . . . . . . . . . . . . . . . . . 14

Glucose Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Pulse Oximeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

E l e c t r o c a r d i o g r a p h ( E C G ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 4

Social Alarm Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

C o n c l u s i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 5

List of Figures

Figure 1 - ZigBee Stack Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Figure 2 - ON World WSN Deployment in Healthcare . . . . . . . . . . . . . 7

Figure 3 - Chronic disease monitoring devices . . . . . . . . . . . . . . . . . . . 9

Figure 4 - HeartCycle system fow chart . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Figure 5 - Assisted Living Scenario . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Figure 6 - Fitness monitoring equipment . . . . . . . . . . . . . . . . . . . . . . . . 13

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Introduction

A working de nition o Assistive Technologywas developed by the United Kingdom RoyalCommission on long-term care (1999) as anydevice or system that allows an individual toper orm a task that they would otherwise beunable to do, or increases the ease and sa etywith which the task can be per ormed. 1

An updated de nition or Assistive Technology(AT) was ormulated in 2001 stating Assistive Technology (AT) is any product or service designedto enable independence or disabled or olderpeople. This de nition was adopted by the authors

o the European Union (EU) SOPRANO ReviewState-o -the-Art and Market Analysis DeliverableD1.1.2 delivered in May 2007.

ZigBee technology will play an important role inthe adoption o Assistive Technology by enablingwireless low-power communication betweendevices and services that oster sa e, healthy andindependent living conditions or the disabled orelderly. In addition to Assistive Technology, ZigBeeapplications in the health and tness domains canaddress several other market segments and needs. The ollowing analysis ocuses on applications o ZigBee technology or chronic disease monitoring,personal wellness and personal tness monitoring.

Overview of ZigBee Monitoring and Sensor

Solutions

As o October 2008, end user applicationsolution commitments to deployZigBee-enabled solutions topped 25.3 millionunits. 2

ZigBee technology is the standard o choice amongother wireless technologies due to its e cient

1 McCreadie & Tinker 2005

2 ZigBee Alliance Chairman Bob Heiles October 2008 ZigBee Alliance MemberMeeting Presentation

low-power connectivity and ability to connect a largenumber o devices into a single network. ZigBeetechnology uses the globally available, license- ree2.4GHz requency band. It enables wirelessapplications using a standardized set o high levelcommunication protocols sitting atop cost-e ective,low-power digital radios based on the IEEE 802.15.4standard or wireless personal area networks.ZigBee uniquely o ers low-latency communicationbetween devices without the need or network synchronization delays as required by Bluetooth, orinstance.

IEEE 802.15.4 de nes robust radio PHY (physical) andMAC (medium access control) layers. ZigBee de nesthe network, security and application ramework or

an IEEE 802.15.4-based system. These capabilitiesenable a network to have thousands o devices ona single wireless network. ZigBee creates robustsel - orming, sel -healing wireless mesh networks. The ZigBee mesh network connects sensors andcontrollers without being restricted by distanceor range limitations. ZigBee mesh networks let allparticipating devices communicate with one another,and act as repeaters trans erring data betweendevices.

The ZigBee Alliances ocus on the healthcare spacehas resulted in the development o the ZigBee HealthCare public application pro le. ZigBee Health Carewas designed or use by assistive devices operatingin non-invasive health care. ZigBee Health Careprovides an industry-wide standard or exchangingdata between a variety o medical and non-medicaldevices.

Public application pro les are agreements or

messages, message ormats, and processing actions. They enable developers to create interoperable,distributed application entities residing on separatedevices. These applications (written by the devicemanu acturer) send commands, request data, andprocess commands and requests over the ZigBeenetwork.

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Application Support Sublayer (APL)

Network (NWK) Layer

Medium Access Control (MAC) Layer

Physical (PHY) Layer

Application (APL) Layer

Application Framework

ZigBee Device Object(ZDO)

NLDE-SAP

MLDE-SAP

PD-SAP

NLME-SAP

Endpoint 240APSDE-SAP

Z D O P u

b l i c

I n t e r f a c e s

Endpoint 1APSDE-SAP

Endpoint 0APSDE-SAP

MLME-SAP

PLME-SAP

A S P M E - S A P

N L M E

- S A P

SecurityServiceProvider

ApplicationObject 240

ApplicationObject 1

Z D O M a n g e m e n t P

l a n e

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The ZigBee Device Object (ZDO) represents aprede ned base class o unctionality upon which

all applications are written. The ZDO creates anabstraction so the developer can ocus on writingapplication-speci c code rather than worryingabout the low-level details. The ZDO provides aninter ace between the application objects, theZigBee Health Care pro le and the applicationsupport sub-layer (APS). It satis es the commonrequirements o all applications operating in aZigBee protocol stack. The ZDO is responsible orinitializing the APS, the network layer (NWK) and the

Security Service Provider.In Figure 1, the areas in light blue depict ZigBeeHealth Care de nitions that are based on the ZigBeespeci cation. Its main attributes are comprised o device specializations de ned by IEEE, includingIEEE 11073 Device Specializations 3 o standards

3 IEEE http://ieeexplore.ieee.org/Xplore/loginjsp?url=http%3A%2F%2Fieeexplore.ieee.org%2FielD%2F4410467%2F4410468%2F04410469.pd %3Farnumber%3D4410469&authDecision=-203

or point-o -care medical device communication.One o the standards that are part o this amily,the 11073-20601 standard [R-11073], is a transport-independent, optimized exchange protocol. Thisstandard orms the basis o the data exchangesbetween the devices that will support the PHHCPro le. This protocol provides methods or: (i)establishing logical connections between devices,(ii) presenting the capabilities o devices, and (iii)servicing communication needs.

ZigBee Health Care Fully Supports ISO/IEEE 11073or point-o -care medical device communication

and provides support or additional devices

The ZigBee Health Care also supports all devicespecializations. Device specializations or a numbero medical devices already exist including the pulseoximeter, blood pressure monitor, pulse monitor,weight scale and glucose meter.



Market Opportunities - Economic Drive

Future Market Projections

According to research rm Research & Markets,wireless sensor networks (WSN) represent anemerging set o technologies that will havepro ound e ects across a range o medical,industrial, scienti c and governmental applications.A wireless sensor network is made up o a group o sensor nodes or devices. Each device possesses theability to monitor some aspect o its environment,and each is able to communicate its observationsthrough other devices to a destination where data

rom the network is gathered and processed. Recentdevelopments in wireless technologies and thesemiconductor abrication o miniature sensorsare making wireless sensor networks smaller andmorecost-e ective or a growing number o uses. 4

The prospects or WSN technology are strong. The market or wireless sensor systems should

4 Research & Markets, Inc. http://www.researchandmarkets.com/reports/c42715

grow rapidly over the next ve to 10 years. Saleso wireless sensor systems could reach US$5 billionto $7 billion dollars over that time. As this marketmatures, sales will multiply year-to-year with aprojected growth rate o 40 or 50 percent. 5 Themain driver behind the uture growth o the WSNis the expanded number o applications that areenvisioned using this technology. 6

Forrester Research estimates that the US chronicdisease device market will grow to US $3.8 billion in2010 and US $26 billion by 2015. 7

The chart above shows gures orecasted by ONWorld or the deployment o wireless sensor nodes inthe healthcare market.

The 2.3 million nodes orecast or 2010 represent a5 percent penetration o the elderly population inNorth America and Japan. The authors o the report

5 Multimedia Research Group, Inc. http://www.mrgco.com/TOC_FK_WSS06.htm

6 Psst. This Is Your Sensor. Your Grapes Are Thirsty, NY Times, July 26, 2004.

7 Forrester Research, Inc. Who Pays For Healthcare Unbound July 8, 2004.


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illustrated with this graphic discuss that i thepotential market includes North America, EuropeanUnion and Japan then the overall total potentialmarket would be 87.8 million people.

Current State of the Market

The US-based Chronic Disease Sel -ManagementProgram (CDSMP) is a sel -management program

or people with one or multiple chronic diseases. 8 This program is used across many di erent chronicillnesses, such as arthritis, diabetes, and heartand lung diseases. The program is a six-week small-group intervention program that is taught bypeer instructions rom a highly structured manual.

The patients taking part in the program experiencedstatistically signi cant improvements in healthstatus, health behaviors and sel -e cacy. In act,this group made ewer visits to emergency rooms. The program has been ound cost-e ective:cost-to-savings ratio was 1:4, the cost being about$200 per patient. The study in China on CDSMP

ound the program applicable or the Chinesepopulation. 9 When this program is automatedthrough wireless sensors and In ormation andCommunications Technologies (ICT) even morecost savings will be achieved or the healthcareindustry. 10

Studies o Netherland seniors over the last 10years indicate that up to 50 percent o seniors areinterested in smart-home applications to aid inhealth, rst responders reaction times and securityimprovement. 11

...We are at a stage where demographic

8 Lorig, 2001E ect o Sel -Management Program on Patients with ChronicDiseases 9 Lorig, 2001E ect o Sel -Management Program on Patients with ChronicDiseases ; Elzen 2007 Evaluation o Chronic Disease Sel -ManagementProgram (CDSMP) Among Chronically Ill Older People in the Netherlands; Siu2007 Evaluation o Chronic Disease Sel -Management Program in a ChinesePopulation.

10 http://www.heartcycle.eu/ Document FP7-216695 HeartCycle Deliverable4.B Nr.1 page 37

11 European Community sponsored SOPRANO Study Deliverable D1.1.2,page 68

ageing is already beginning and will soon startto accelerate. In the meantime, the deploymento computers, the Internet, and mobilecommunications in all aspects o the economy,services, and everyday li e continues apace. These two trends can hardly pass each otherwithout interacting in a multitude o ways

Important market drivers are the dimension o demographic change, the related developmento state o the health o older people, speci cproblems o the increasing older generation,the resulting estimated increase or care,current structure o the care and the expectedcost pressures on health care and social securitysystems. 12

Applications of Wireless Sensors for Better

Health Care

The healthcare domain presents opportunities or asigni cant number o applications o wireless sensortechnology. The ollowing sections ocus on threebroad health monitoring applications that includeChronic Disease Monitoring, Personal WellnessMonitoring, and Personal Fitness. Within each o these applications, we describe several speci c useso wireless sensor technology.

1. Chronic Disease Monitoring

Chronic diseases contribute to 75 percent o medicalcare costs in the US. 13 They encompass a wide rangeo health problems including diabetes, asthma, heartdiseases and sleep disorders. In many cases, chronicdiseases require some kind o health monitoring,

especially in the later stages o the diseaseprogression. Since not all chronic disease monitoringis the same, we urther re ne the category as ollows

Episodic patient monitoring is o ten utilized innon-critical patients to track speci c indicators

12 European Community sponsored SOPRANO Study Deliverable D1.1.1,page 164 13 CDC - http://www.cdc.gov/nccdphp/overview.htm


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and identi y the progress o the disease orrecovery

Continuous patient monitoring is o tenassociated with acute conditions that requireconstant or requent measurement o healthstatus.

Patient alarm monitoring can also trigger alarmsbased on preset conditions that are speci c tothe patient and the disease.

Figure 3 shows a ew examples o monitoringdevices that can take advantage o ZigBee wirelesstechnology and provide com ort and ease-o -usein the Chronic Disease Management monitoringapplications.

Episodic Patient Monitoring Scenario

This use case deals with non-acute or episodicpatient monitoring. In this scenario, the patientsvital signs (e.g. heart rate, temperature) anddisease-speci c indicators (e.g. blood pressure,blood glucose level, EKG) are monitored todetermine anomalies and spot trends. Themonitoring is done periodically.

All the in ormation collected by the medicalsensors is time-stamped and securely orwarded toa gateway that unctions as a patient monitoringsystem. Additionally, the gateway orwards theaggregated in ormation in a secure way to adatabase server. The medical personnel and the

amily can access the in ormation stored in the

database server to monitor the progress o thedisease.

As an example, certain types o diabetic patientswould have to monitor their blood glucose level onlya ew times a day. In this case, the application wouldnot have to poll the glucose meter as the patient isresponsible or initiating the data sampling process.Since all the in ormation is time-stamped and thepatients in this scenario are not in a critical state,the latency o transmitting the in ormation to thegateway is not critical. The data can be stored locallyat the medical device and/or gateway and securelytransmitted only when a predetermined amount o data is gathered. It is also possible that the medicaldevices and/or the gateway per orm some type o data compression to minimize bandwidth use.

This use case also covers periodic, routine medicalexams, where a number o medical sensors are worn


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by the patient during the medical exam. During theexam, all the readings are interpreted by the primaryphysician and archived in the patients database.

Continuous Patient Monitoring Scenario

In this situation, the vital signs (e.g. heart rate,temperature, pulse oximeter) are monitored on aconstant basis to allow continuous measurement o patients health status at rest or during mild exercise

or purpose o treatment adjustment, recovery ordiagnosis. Continuous, in this use case, is de nedas a measurement sampling rate acceptable or thepurpose o continuous health monitoring.

The vital signs measurements wave orms (e.g. pulsepleth wave or heart rate) are securely streamedto an on-body data collection unit or data usionand/or sequential storage. The data is securely

orwarded rom the data collection unit to ano -body gateway (e.g. PC/laptop, PDA or mobilephone) or sensor con guration, storage and dataanalysis. Alternatively, the data can be sent directlyto a mobile terminal.

The patient or the care provider remotely activatesthe on-body sensors via the o -body unit. The

measurement data rom the body sensors is securelytransmitted continuously to the on-body unit, whereit is temporarily stored. Subsequently, the recordedmeasurement data is securely sent to the o -bodyunit via batch transmission or persistent storageand urther analysis by the health care provider.Optionally, an o -body unit can also be used orsecure wave orm viewing during the measurement. The health care pro essional uses the captured datato provide the appropriate diagnosis or to adjust the

treatment level. To illustrate how this use case would be deployed inreal li e, consider the ollowing scenario. A patientis suspected o su ering rom arrhythmia. Thesymptoms o this condition (e.g. atigue, aintingand dizziness) are caused by abnormal heartbeatsthat can cause the heart to be less e cient. Thesymptoms are very brie and hard or the patient

to characterize. Instead o subjecting the patientto cardiac stress to induce the abnormal heartbeats while the patient is examined in a hospital,the patient is given a wearable EKG device. TheEKG sensors are used to monitor the conditioncontinuously over longer periods o time until theabnormal heartbeat is detected. Once detected, thedata is securely sent to the physician or analysis. I the event is serious enough, an appropriate network device (e.g. telephone, PC/laptop, PDA) can be usedto call or help.

Patient Alarm Monitoring Scenario

In this scenario, the patients vital signs (e.g. heartrate, temperature) and disease-speci c indicators

(e.g. blood pressure, EKG, EEG) are monitored on acontinuous basis. The data collected by the medicalsensors is time-stamped and securely orwarded toa gateway that acts as a patient monitoring system.Additionally, the gateway securely orwards theaggregated in ormation to a database server. In thiscase, a certain minimum bit error rate and maximumend-to-end latency not to exceed a ew secondsshould be guaranteed.

At pre-determined settings, alarms are issued andresponses/actions could be triggered automatically.For example, i during the monitoring o a diabeticpatient the blood glucose level alls below a certainthreshold, an alert can be sent to the patient,physician(s) and/or medical personnel. Increasingthe sampling rate o a given monitor can also betriggered once an alarm has been asserted. The alarmcan be issued either by the medical device or bythe gateway. In the ormer case, the medical devicewould potentially be required to communicate with

other ZigBee devices that use a di erent pro le. Inthe latter case, the gateway might be required tocommunicate with other non-ZigBee devices.

A speci c example o a patient alarm monitoringapplication can be seen in the HeartCycle 14 project.

14 http://www.heartcycle.eu/ Document FP7-216695 HeartCycle Deliverable4.B Nr.1 page 6


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11/15 2009 ZigBee Alliance. All rights reserved. www.zigbee.or

HeartCycle provides a closed-loop diseasemanagement solution able to serve both heart

ailure (HF) patients and coronary heart disease(CHD) patients, including possible co-morbiditieshypertension, diabetes and arrhythmias. Thisis achieved by multi- parametric monitoringand analysis o vitalsigns and othermeasurements.Adverse event alarmsare generated orimmediate pro essionalattention and anautomated decisionsupport systemderives therapyrecommendations

or the in ormationacquired. Vital bodysigns will be used totrack health statusand the impact o thecurrent treatment,showing the patientthe importance o adherence to the

treatment, motivatingimproved treatmentadherence and a more active role in their care.

The regular measurement o vital signs enables earlydiagnosis and warning o developing problems.Furthermore, it allows closer monitoring o thee ects o medication and li estyle, making morepersonalized treatment plans possible. The systemcontains a patient loop interacting directly with thepatient to support the daily treatment. It shows thehealth development, including treatment adherenceand e ectiveness. An educated and motivatedpatient can improve his/her treatment complianceand health. The system also contains a pro essionalloop involving medical pro essionals (e.g. alertingto revisit the care plan). The patient loop is securelyconnected with hospital in ormation systems, toensure optimal personalized care.

Given the act that patient alarms will requirestringent quality o service assurances, ZigBeemonitors will be robust and will comply withapplicable regulatory requirements.

2. Personal Wellness Monitoring

Personal WellnessMonitoring is an areathat will rst ocuson individuals age 65or older. As an initial

ocus, the monitoringconcerns the personsactivity and sa ety. Asthis market develops,

adoption o thistechnology will ndapplications or thegeneral population. The Personal WellnessMonitoring applicationis shown in the above

gure depictingseveral aspects o the assisted livingscenario. The scenarioin Figure 5 shows

several devices that would be used in managing thecare, sa ety and activity o the residents in an assistedliving acility. The in ormation securely collected bythese devices is centrally managed and analyzed. It isin such scenarios that ZigBee technology can providesolutions addressing the needs o the medical sta and the residents.

Senior Activity Monitoring Scenario

This use case ocuses on monitoring an elderlypersons daily activity. Besides a number o wearablemedical sensors/devices that monitor the vitalsigns (e.g. heart beat, temperature), this use caseinvolves monitoring other non-medical sensorssuch as environmental sensors, motion sensors,home sensors (e.g. bed, door, window), etc. All thein ormation rom these sensors is sent to a gateway

2009 ZigBee Alliance. All rights reserved. www.zigbee.or


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or recording and processing. The caregiver and/or amily members can, with permission, accessthis in ormation and assess the well-being o theelderly person. I certain pre-determined eventsoccur, automatic responses could be triggered. Forexample, the caregiver can be alerted via a textmessage i the heart rate o the elderly person isabove a threshold value.

I an elderly person has to ollow a certain dailyschedule such as taking a weight measurement inthe morning, obtaining glucose level readings atnoon and at 6 p.m. and completing an oxygen levelreading a ter dinner, the caregiver can monitor thedaily activity status o the person. I certain routine

activities are not completed, the person can be senta reminder. Should the person not respond to setnumber o reminders, the caregiver can be sent analarm.

In this use case, the data collection unit and thegateway will be able to handle di erent pro lessince they accept and potentially send in ormation

rom/to both medical and non-medical devices.

The same is true or any devices with multiplesensors, such as a watch with an accelerometer and agyroscope or all detection, as well as health-related

unctions.

This use case also covers journaling. This is atechnique that is recommended or patients to helptheir physicians diagnose certain conditions, suchas rheumatic disease. Using this technique, patientsrecord pharmaceutical, environmental or behavioralchanges and correlate them with body unctionchanges (e.g. atigue, motion range, etc.). Thein ormation provided by both the patient and by theother medical or non-medical devices in the homenetwork is recorded and stored in a database server

or later review by the physician and/or amily.

Safety Monitoring Scenario

This case deals with monitoring the sa ety o thehome environment. The home environment ismonitored or sa ety hazards including toxic gases,water and re. Additionally, the vital signs (e.g. heartbeat, temperature) o the persons in the home arealso monitored. The data gathered by the medical


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and non-medical devices is analyzed locally and/or securely orwarded to a gateway or processingand storage. I predetermined events occur, thecaregiver and/or amily receive alerts. Automatic

responses can be triggered when certain eventsoccur. It is worth noting that the Sa ety Monitoringapplications will be addressed with a combinationo several ZigBee pro les, including the ZigBeeHealth Care and ZigBee Home Automation publicapplication pro les.

3. Personal Fitness Monitoring

Personal tness is also a market segment showinghigh potential or use o wireless sensor technologyboth in the home and in health tness centers. Alarge variety o devices and services are envisionedto accommodate the growing tness market.

Monitoring and Tracking Fitness Level Scenario

This use case ocuses on tracking the tness levelor progress made by an individual. A number o parameters that the individual wishes to monitor are

recorded as the individual per orms his/her workoutroutine. For example, while running on a treadmill, theindividual monitors his/her heart rate, temperatureand blood oxygen level. This in ormation, obtained

rom medical sensors that are worn by the individual,are securely streamed to a gateway or a collectiondata unit and displayed on the treadmills console inreal time along with other per ormance in ormationprovided by the treadmill. Additionally, the gatewaysends the in ormation to a database server or recordkeeping. Note that the in ormation need not be sentin real time, but may be collected and transmitteda ter the workout routine ends. A ter the workout, theindividual can review a history o these parameters totrack and analyze their tness level.

In this use case, the application polls each sensortype at a di erent rate. For example, the applicationwould poll the temperature sensor two to our timesa minute and the pulse monitor twice per second. Thelatency requirement or this application should be lessthan one second.

Personalized Fitness Schedule Scenario

This scenario ocuses on personalization o the tnessschedule o an individual. The schedule to be olloweby the individual can be entered by a trainer or theindividual. For example, training or a marathoncould include running on a treadmill according to aschedule designed by his/her trainer. For each trainingday, the trainer schedules the distance, the pace, andthe maximum heart rate at which the individual isto train. The trainer would also like to monitor theindividuals respiration pattern. While the distance andthe pace are provided by the treadmill, the heart rateand the respiration are monitored by wireless medical

devices worn by the individual.

The in ormation collected by these medical devicesis securely streamed to a gateway and displayedon the treadmills display panel. Additionally, thegateway would also securely send the in ormation toa database server or record keeping. I the heart ratespikes to a value that is higher than the value that isset by the schedule, the medical device communicates


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with the treadmills control unit to reduce theworkout gradually until the heart rate alls again inthe preset interval.

Alternatively, the medical device might simply sendan alarm to the gateway. Upon receiving this alarm,

the gateway will initiate the communication withthe treadmills control. Yet another possibility wouldbe or the application to determine when the heartrate is above the preset maximum value and toinitiate itsel a command to the treadmills controlwithout involving either the medical device or thegateway. In all o the above scenarios, it is assumedthat the treadmill is controllable by a ZigBee devicethat could use an existing public application pro le,such as ZigBee Home Automation

In this use case, the medical devices securely sendtheir readings to the gateway at a xed rate. Thelatency requirement or this application should beless than one second.

Example Products Applicable for Health Care

The application areas described in the previoussections ocus on products targeted or thehealth wellness and tness areas. Several o therepresentative products are described in the

ollowing sections.

Glucose Meter

This is a device that measures the approximateconcentration o glucose in the blood. It is usedby chronic disease (e.g. diabetes) managementapplications. For current generation devices, the

requency o measurement is several times a day.Future generation devices equipped with ZigBeeHealth Care are expected to unction in continuousmode and the requency o measurement isapplication-dependent.

Pulse Oximeter

This is a device that indirectly measures the amounto oxygen in a patients blood. The requency o measurement is application-dependent (typically

once a day). Pulse oximeter sensor devices equippedwith ZigBee Health Care will measure the amounto oxygen in the users blood and store and transmitthat in ormation to an aggregating device.

Electrocardiograph (ECG)

This is a device that records and measures theelectrical activity o the heart over time. The

requency o measurement is a ew times a day orcontinuously or periods o a ew hours in some usecases. ZigBee Health Care enabled devices will allowthe user to record and monitor electrical activity o the heart while preserving the li estyle and mobilityo the user. The improved convenience and mobilitywill enable widespread use o such devices in cardiac

monitoring and tness applications.Social Alarm Devices

Social Alarm devices allow individuals, in theirown home or a residential-care acility, to raise analarm and communicate with a caretaker when anemergency situation occurs. The caretaker may be amonitoring center, a medical care team or a amilymember.

Three initial devices are targeted.Fall Detector this device detects that theindividual has allen and raises an alarm. Devicesequipped with ZigBee Health Care will wirelesslytransmit the activity o the user based on theposition o the sensing element.

Pendant / Wrist Transmitter a waterproo devicethat allows an individual to raise an alarm bypressing a button on the device, or example.

Devices equipped with ZigBee Health Care willenable the user to wirelessly alert appropriateresources in emergency and other situations.

Social Alarm Control and Indication Equipment(SACIE) this device receives alarm signals

rom the all detector and wrist transmitter andrelays them to designated recipient(s). It alsooptionally opens an instant hands- ree voice


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communication link between the individual andthe recipient. Devices equipped with ZigBeeHealth Care will enable the user to wirelesslycommunicate with the emergency responsepersonnel and allow them to locate the user inthe network.

The SACIE may have other unctions, such asverbal reminders to the individual regardingregular medication, reducing the risk o over- orunder-medication. Similarly, reminders regardingregular health checks can help ensure that checksusing some o the medical devices covered by thispro le are carried out according to a schedule. TheSACIE has many similar unctions to those o thegateway / access point, and may be combined with

it.

Conclusion

There are several trends in the healthcare andwellness areas that may potentially reshape themedical, and tness industries. The shi t romreactive to proactive healthcare and wellnessis ueling an increased vigilance and serviceapplications in targeted tness and chronic diseasemanagement. Additionally, increased adoption o connectivity and communication technologies isenabling remote health and wellness services on amuch wider scale. The missing piece o this puzzleis wireless connectivity and more speci cally, lowpower wireless connectivity.

The low power wireless component preservesmobility while the low-power component ensuresthat sensing and monitoring devices preserveour independent li estyle. The ZigBee Health Care

public application pro le is designed rom the startwith the use cases taking these current trends intoaccount. ZigBee Health Care can be implementedto create a scalable network o low-powerwireless nodes speci cally designed to sense andmonitor the health and well being o individualsin applications that include chronic diseasemanagement, tness, and aging independently. TheZigBee Health Care inherent traits that make such

applications possible include very low power use,fexible network topologies, data communicationsecurity, and wireless license- ree bandwidthpublically available everywhere in the world, anda robust ecosystem o technology suppliers andproduct manu acturers that ensure a consistentparts supply and strong competition creating theeconomies o scale needed to allow or the rapidintroduction o wireless sensing and monitoring orhealth care.

This unique combination o bene ts presented byZigBee Health Care eliminates barriers and allows theindustry, governments and individuals to embracethis critical piece in reducing health care costs. Italso creates a new class o tools that deliver vital

li e saving and li e a rming bene ts that can servehumanity.


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WSN for Healthcare