|
Wireless
Data Access in the Clinical Environment
|
Abstract
Cedars Sinai
Medical Center is using web and wireless technology
to provide its physicians access to clinical records. It
is available inside the building (through PCs linked to
the network by cable or wireless access), as well as a pilot
project to use clamshell hand-held computers
in a clinical area. (Clamshell is the term used to describe
a computer that consists of two hinged components, the screen
and keyboard, whereas the Palm consists of a touch sensitive
screen only.) Outside the building, physicians can monitor
their patients through Palm V and Palm VII computers, whether
they are on the move, in their private offices or at home.
This case study details:
the practical implications of getting critical information
to remote employees
the importance of starting with web-enabled applications
and the relative ease of adapting them for use through a
mobile browser
practical experience of using Palm computers to present
information
contrasting experience with clamshell
computers, where data entry is important
the benefits of quicker access to information.
These aspects are explained by Ray Duncan, a medical doctor,
who is director of technology and architecture for the Department
of Enterprise Information Services. He is uniquely qualified
to give an insight into both the users requirements
and the technology implications.
|
Creating the Mobile Enterprise
Context
Founded in 1902, the world famous Cedars Sinai Health System is
the largest non-profit hospital in western US. It occupies a campus
close to Beverly Hills in Los Angeles. The Center is committed to
providing the best outpatient, acute, sub-acute and home patient
care, as well as breakthrough biomedical research, graduate and
undergraduate medical education and community service.
The biggest business unit is the Cedars Sinai Medical Center, an
850-bed hospital providing tertiary treatment, including transplants
and other advanced surgery and treatments. Each building has a wired
network and all buildings on the campus are linked together into
a single network by a fibre optic ring.
The Medical Center has completed four different wireless pilot projects.
It has wireless network access in accident and emergency clinical
area and communal business areas. Access to the network from outside
the hospital is through Palm hand-held computers. Medical staff
in the paediatric department are interacting with clinical systems
through clamshell computers.
Wireless Network
As the first step to switching to a wireless network infrastructure,
the hospital has wired all its conference rooms, meeting rooms and
auditoria with wireless access points, using wireless Ethernet 802.11(b).
Staff now use laptops with wireless cards to access electronic mail
and medical information while working in these areas.
The system is also being used in the emergency department, so that
patients registration details can be gathered and entered
at their patients bedside.Duncan explains that this is a service
that patients have been requesting for a long time.
The hospital is intending to go completely wireless for new networking
areas. Says Duncan:It is more economic, as at $200 per user
it is expensive to pull cable. You can easily put up an access point
and buy some wireless cards. It is much cheaper,and when you move
people around you dont have to pull cable again.
The Medical Center is about to construct two new buildings and Duncan
is considering networking them mainly with wireless access points.
Cable will only be used for really high bandwidth applications that
need 100m/bit Ethernet or fibre-channel connections, such as digital
video and high-resolution diagnostic imaging workstations.
Web Access
The Medical Center has invested a considerable amount of effort
in creating a Web Viewing System (Web/VS) for its clinical systems.
This gives clinicians a user-friendly interface to legacy hospital
information systems, bedside clinicalsystems, clinical data repositories
and other sources of biomedical information.With 400 PCs in the
clinical areas, no physician is ever more than six metres or so
from access to the information they need.
However, there was a clear need to be able to access these systems
quickly and easily from outside the hospital. Many of the hospitals
patients are treated by private doctors with their own offices away
from the campus. Also, both private and staff doctors need access
from home or when on the move.
With the use of hand-held computers spreading throughout the hospital,
the solution was to provide remote access to medical systems through
communications-enabled Palm VII machines that automatically connect
to BellSouths Mobitex network. Duncan used these to access
a Palm Viewing System (Palm/VS). He explains why: We chose
Palm VII because the networking was already built in, giving us
a one stop shopping solution. You just take it out of
the box, turn it on, put in your credit card number and it works.
With other solutions, you have to buy a hand-held computer from
one supplier, a communications card from another and get a contract
from third supplier and then make them all work together. With the
Palm VII the integration just works immediately for the user.
As the medical systems were already web-enabled, all that was required
was to build special versions of the web applications for access
through the Palm. Says Duncan:Essentially you just tweak what
you already have for the small screen sizes. If you already have
web applications built and security figured out, it is really a
very simple thing to convert it to the Palm VII. When you know how
to do it, it only takes a few hours. We completed the task in a
weekend. Security for the Web works just fine on the Palm using
the same encrypted sessions.
As well as being specially formatted for the Palm VII screen, the
web pages include special meta tags that embed version
information and update the Palm VIIs history list.
Another difference from conventional web applications is that the
Palm architecture allows static text (such as on-line help), forms,
images and icons to be resident on the device, increasing responsiveness
and decreasing network traffic. Duncan says: The design of
Palm/VS is tightly constrained by the bandwidth of the wireless
networking connection, the small screen size and the capabilities
of the Palm VIIs Clipper web browser. The functionality
of Palm/VS is therefore only a small subset of the functionality
and data types available in the Web/VS application for desktop personal
computers.
Once Duncan had ported the applications, it automatically utilized
the Palm wireless networking and the BellSouth wireless Mobitex
network. This is a packet data network with an always on
connection that provides a data rate of approximately 8kbps.
The ongoing subscription cost for the network connection ranges
from $10 to $40 a month for traffic quotas ranging from 10 to 300
kilobytes per month. A flat-rate pricing plan for unlimited network
traffic is also available for $45.
Additional connectivity is provided to Palm V machines using an
OmniSky wireless modem that links to AT&Ts Cellular Digital
Packet Data (CDPD) network at approximately 19.2kbps. It is otherwise
functionally equivalent the Palm VII from the users perspective.
Palm VII
Unlike personal computers, the hospital does not take a centrally
funded,standardized approach to hand-held computers. Each business
unit is free to purchase whatever machines they wish out of their
own budget. However, only the Palm VII and Palm V can have access
to clinical systems. Duncan explains: We dont tell people
what to buy, so they buy whatever they want. Every model of every
personal digital assistant (PDA) that ever existed is out there
somewhere, but if they want remote wireless access to laboratory
results they have to buy a Palm VII.We dont stop them buying
any other machines because they can still get remote access to medical
systems through a personal computer.
In practice, between 100 and 200 physicians user Palm machines to
give them completely mobile, web-based access to clinical information
anytime, anywhere.
As well as using them for e-mail and schedules, the main clinical
use is to obtain information, such as laboratory results, surgical
reports, consultations, intensive care unit and emergency room visits.
There is also a physician and employee directory for telephone numbers,
e-mail and fax numbers.
Some specialist areas have no need for remote access, but the Palms
are most popular with physicians taking care of very complex or
very sick patients, such as intensive care specialists, cardiologists
or anaesthesiologists. Duncan continues: We do a lot of advanced
surgery and have several large intensive care units. Physicians
with very sick patients are often away from hospital and need results
quickly. The Palm machines allow them to closely monitor their patients
and extends their ability to provide medical care outside the building.
They could get the same information by calling the hospital and
getting the nurse to call the laboratory and then call them back,
but that takes the nurse away from looking after the patient.
Problems Experienced with the Palm Devices
Duncans practical experience with use of the Palm VII has
identified a number of concerns and issues related to the Palm VII
device. First, the Palm VII browser does not support JavaScript,
cookies, caching programs, nested HTML tables, frames, horizontal
scrolling or a number of other features found in desktop web browsers.
Session state must be maintained by passing information back and
forth in hidden fields between forms on the client and scripts on
the server. This inevitably leads to the divergence of separate
code bases for web browser clients and Palm VII wireless clients,
increasing the overhead of program maintenance. Says Duncan: The
Palm VIIs provisions for security and encryption were better
than we expected. Unique Device ID within wireless transactions
that can be used to correlate the users login with the device
itself. However, the local page cache or history list
persists from one launch of an application to the next, and cannot
be cleared automatically by the application when the user logs out.
This makes it possible for someone to view patient data from a previous
session without logging in. The workaround is to put global password
protection on the Palm VII, but users regard this as quite inconvenient.
Another security weakness is inherent in the Palms handwritten
input Handwritten passwords must be displayed on the screen so that
the user can confirm that the individual characters were recognized
correctly, so a user could inadvertently reveal their password.
The Palm VII mitigates this risk by popping up a special dialogue
box to accept passwords and removing the information from the screen
immediately after the input is completed.
HP Jornada
The second pilot involving hand-held computers is in the paediatric
ward and clinics, where junior doctors (residents) use
them to interact with clinical systems. Although they need to look
up results, which the Palm users do, they also needed to enter information
about patients.
Duncan purchased a range of different hand-held devices for the
residents to try out and they selected the Hewlett-Packard Jornada
680 clamshell running Microsofts Windows CE operating
system. Duncan says: That was the one they liked best. It
had a full keyboard for entering information and fits in the pocket
of their white coats.
This machine has a PCMCIA slot that takes a Lucent WaveLan card
to access the wireless network. Sixteen machines are in use and
four act as spares. Instead of having their own machines, the residents
pass them on as they change shifts.
Duncan finds that the Jornada web browser works very well, but the
machines have suffered quite a bit of breakage, with all four spares
in use some of the time. He explains: It isnt the fault
of the Jornadas, because they get a different kind of use from the
Palms. The hospital is a hostile environment.They get carried around
open, people type with one hand and hold it with the other, they
get lost, they get dropped.They are heavier than the Palm so when
they fall there is more chance that they break.These users are very
busy people and their minds are on patient care, not protecting
their PDA.
Business Benefits
Duncan explains what he feels is the main benefit in the hospitals
use of wireless devices:The main benefit of wireless technology
is that it is the most flexible and economic way to enable our goal
of getting information to the point of care. We
have really seen a huge difference in the last year in the affordability
and stability of wireless technology and when the picture is fully
stabilized it will be inexpensive and easy to deploy.
Duncan explains that as the incremental cost of wirelessly enabling
hand-held computers is so small, he did not attempt a business case.
Having already built the web applications, getting them to run on
the hand-held machines required very little work. He adds, we
didnt make a big effort to cost justify it, we just went ahead
and did it.
Nevertheless, the machines are giving users quicker and easier access
to clinical information in order to support patient care. It saves
both physicians and nurses the time involved in chasing the information
by telephone. That they find this valuable is shown by the tremendous
pull through demand. As they start to use hand-helds
to access clinical information, physicians are asking for more and
more functionality to be added.
The Future
The medical system has no immediate plans to standardize the use
of hand-held computers. The next major goal is to deploy wireless
networking throughout all of the patient care areas in the medical
centre. Says Duncan: The Palms and Jornadas are a convenience
but our real focus for this year will be to fully build out our
wireless infrastructure inside the hospital.
Conclusion
Duncan remains enthusiastic about the scheme: The acceptance
of wireless applications among the attending staff and faculty
has been excellent. The clinicians really love it and the more functionality
we give them the more they want.
Duncan has learned a lot about the Palm and Windows CE machines,
as he explains: They each have their strength. We like the
Palms because they are extremely lightweight and elegant, yet rugged.They
have excellent battery life and we have had excellent support from
Palm Computers. They are very good at displaying information, but
there are situations when people really want a keyboard so we also
use clamshell machines.
It is clear to Duncan that the wireless deployment of clinical applications
has many compelling advantages. He expects such applications to
proliferate rapidly over the next few years as wireless technology
improves, hand-held computers and cellular phones converge and bandwidth
costs decrease. However, he adds a warning: It would be an
exaggeration to say that hand-held computers are life savers. We
are tying to make information available to doctors, though whatever
route they prefer to use. Nevertheless, these machines save them
time and make life their easier, so they are very excited about
them. Most doctors want to make people well and care very deeply
about the quality of care they give. Our goal is to get information
to the bedside so they can use it to make the right decisions and
wireless enables us to do that.
Key Learning Points
1. Wireless access to a network can be an economical way
to provide information to customer-facing staff at the point
of service, whether medical care or any other type of service.
However, it cannot yet cope with high bandwidth traffic.
2. Providing web access through a personal computer is an
important first step to providing wireless access to information.
3. There is value in a solution that pre-integrates computer,
communications device and mobile network.
4. Functionality may be constrained by the bandwidth of
the wireless networking connection, the small screen size
and the capabilities of the mobile computers web browser.
5. The Palm form factor is very good for viewing information,
but a clamshell is better for entering information,
in terms of ease of use.
|
Editors note: This case study is an excerpt
from a larger 250-page research and case study-based report entitled
"Creating the Mobile Enterprise - how to achieve competitive
advantage through wireless technologies." And was produced
by:
The Business Intelligence Corporation of the UK
http://www.business-intelligence.co.uk
The full 250 page report can be purchased directly
from this
link
PDA cortex wishes to extend our thanks to Fiona
McShane of Business Intelligence for her kind permission to reprint
the CEDARS SINAI case study.
|
|