Expert systems a feast
for leaner laboratories
By this spring, laboratorians at St.Vincent Health System,
Little Rock, Ark., will be able to glance at a computer screen to
see whether a venipuncture that is stat or timed is overdue. The machine
will flag any test that is approaching overdue.
In Baton Rouge, La., a computerized system at Our Lady of the
Lake Medical Center monitors results of hepatitis panels and delivers
interpretations to the requesting physicians.
When ACM Medical Laboratory, Rochester, NY, runs a specimen from
a dialysis patient, the laboratory system automatically adds "pre-dialysis"
or "post-dialysis" to the bar-code label to prevent a mixup.
So-called expert systems, which as part of a laboratory or hospital information
system respond to programmed rules governing how and when lab tests are run,
are finding more use in these days of tight budgets and resource constraints.
Although resistance remains to allowing a machine to take over tasks once reserved
for technologists or pathologists, that resistance is waning, thanks to more
sophisticated systems and a better understanding of how to use them.
Responding to clients’ needs
One area where hospital-based and reference labs make extensive
use of expert technology is in delivering results to their clients
in the requested manner. In the past, if a physician’s office wanted,
say, stat results delivered immediately by phone and all other results
faxed daily at 4 PM, laboratory staff would have to commit those
preferences to memory. Today, expert systems do everything from
popping up a reminder message on a callback screen to automatically
faxing hundreds of results.
Physician offices that contract for laboratory work with Arnot
Ogden Medical Center, Elmira, NY, can receive results in several
ways. "We can fax them all the lab results, just the critical results
or just the stats, or other designated kinds of tests," says Boyd
Wilson, MD, medical director of the laboratory.
Physicians with patients on anticoagulants may want prothrombin
time results faxed immediately, he says. A group of obstetricians
who do fertility testing prefer to receive all hormone levels at
a certain time each day. Transplant centers served by the laboratory
get all their patients’ test results faxed immediately. "The Arnot
has used this type of logic for a number of years with our McKessonHBOCPathLab
system," says Dr. Wilson. "Now we are in the process of building
similar rules into our new SIA Molis system. By having the computer
check results against the client name and respond to their faxing
criteria, it eliminates a lot of the manual labor that the techs
used to do and the errors associated with a manual system."
Alliance Lab Services, part of the Health Alliance of Greater
Cincinnati, serves five hospitals, as well as outpatient centers,
80 nursing homes, physician offices, and pharmacies. Physicians
can receive their results by fax or online every hour, or as soon
as lab tests are completed, or at designated times of day. Within
the hospitals, results are delivered electronically via the hospital
information system and printed automatically if they’re urgent.
Alliance’s expert technology is supplied by McKesson’s Horizon Lab,
says Joanne Griffith, executive director of laboratory services.
Pharmacies also access results online or get a fax of daily values,
such as creatinine levels for patients on aminoglycosides.
Our Lady of the Lake Medical Center has set up its Discern Expert,
part of Cerner’s PathNet LIS, to respond to a series of rules on
when customers should be called back. "The technologist can just
keep running results and doesn’t have to stop to look up a phone
number or do a fax," says Donna Hoglen, LIS supervisor. Discern
Expert will put results into a callback queue or fax them, depending
on clients’ preferences. Results that need quick response, such
as a glucose of 500, are flagged as urgent and put into a separate
queue for immediate callback by a clerk.
"Many of our clients have their own rules," says Martha Delaney,
director of new business development for ACM Medical Laboratory,
which consists of a reference lab and three hospital-based facilities.
Before going live on SCCSoft Computer Consultants’ expert system
several years ago, ACM’s technicians and customer service representatives
had to remember each client’s requirements. "We did it all manually,"
Delaney says. "Fortunately, our volume was much smaller."
Today, with more than 1,000 clients, ACM depends on its expert
technology to send faxes at certain times and it depends on its
online call list to alert staff to make phone calls. Oncology clients
want test results immediately. Other clients get a summary list
faxed at a specified time. Some clients get their results electronically.
The system also accepts verbal orders from physicians and automatically
faxes back the order for a signature. Client- or physician-specific
rules take precedence over general ACM rules.
ACM also takes advantage of the multi-site routing capabilities in its expert
system. The multi-site rules can be used to shift work from one site to another
at peak testing times, to route work from a client to an alternate outside reference
lab, and to change routing on holidays. "The testing site determined by the
rules prints on the specimen label," says Delaney. "And rules change over time
based on laboratory and client needs."
Expert systems are also used to autoverify results; those outside
the norm are flagged for additional attention. The technology can
be set to differing parameters. When an expert system first goes
into use, parameters typically are defined narrowly so results are
more likely to be scrutinized by a technologist. As acceptance of
the new technology grows, the parameters can be broadened.
The Cleveland Clinic Foundation, which uses the Sunquest FlexiLab
LIS, has configured autoverification parameters for hematology and
chemistry tests. "This is a common feature of LISs today, but a
lot of labs don’t make very extensive use of it," says Walter Henricks,
MD, director of laboratory information services. Results typically
are checked by a medical technologist, who validates them or sends
outliers back for retesting. But in a modern laboratory, "you have
thousands of tests and values being churned, and the technologist
isn’t always able to figure out if abnormal values are inappropriate
for a given patient," he says.
An expert system can sort through thousands of results much more
consistently than a human, he says. That means technologists must
scan only those results that fall outside parameters. For example,
a potassium test that comes back as a 10 "would fail autoverification
and show up on a list that’s checked by a person in the lab," he
At Alliance Lab Services in Cincinnati, "expected" results are
automatically reported to the client, while results that don’t match
delta failures are put on hold and displayed on screen for the technologist
to check. Says Griffith: "We use a review list that displays everything
that needs to be looked at. Results that have been autoverified
as expected never get to the screen. All the tech has to deal with
are things that are unexpected."
Using the LabWizard expert system from Pacific Knowledge Systems,
Clinipath Laboratories, Perth, Australia, is autovalidating 70 to
95 percent of lab results in such areas as thyroid, lipid, sex hormones,
chemistry, iron, hepatitis, serology, and prostate-specific antigen
testing. "This [autovalidation] will become higher as we become
more confident in the interpretation," says Wayne Smit, MD, chief
executive of the diagnostic lab. LabWizard has been particularly
valuable in alerting physicians to abnormalities on related test
profiles, such as high urine white cell counts and elevated PSA
levels or elevated low-density lipoprotein/cholesterol and hypothyroidism.
Dr. Smit says Clinipath reviews one to 10 percent of autovalidated
results as a quality measure.
St. Vincent Health System is autoverifying urinalyses with its
Horizon Lab expert system and soon plans to add complete blood cell
counts. Len Rea, chief technologist in hematology, says a CBC is
more complex than a urinalysis. "With a CBC, you have to look at
something like 18 pieces, any one of which can set off a flag,"
he says. "I don’t want to just look at normal values on a new admission
and release the results. I also want to be able to autoverify that
abnormal results haven’t shown significant change in a given time
when a technologist has previously confirmed the results."
The expert system also helps St. Vincent adhere to government
regulations in billing for tests, Rea adds. For example, a normal
macroscopic urinalysis is reported to the physician and billed for
as a macro. But if results are abnormal, the lab performs a microscopic
urinalysis. Under government regulations, that must be billed for
as a complete urinalysis as opposed to two tests. "The system handles
that automatically and keeps us out of trouble," Rea says. On the
other hand, he adds, the expert system can maximize potential revenue
by recognizing each venipuncture and attaching a phlebotomy fee
once per day.
Similarly, at Our Lady of the Lake Medical Center, the expert
system can sort through hematology tests and bill at the appropriate
level. Because of the complexity of the tests, "we were often billing
at the lower CPT code to be on the safe side," Hoglen says. "That
meant we were basically writing off more complex cases." Once a
rule has been programmed into the system, "the computer monitors
our testing and bills accurately for all the work that was done."
ACM Medical Laboratory has set up its expert system to track laboratory problems,
including where they originate and how they are resolved. With hundreds of clients,
technologists may not recognize a pattern occurring, "but the system does,"
says Delaney. "We can locate where we’re having an unusual number of problems,"
such as a physician’s office using the wrong specimen tubes. ACM then handles
the problem diplomatically, perhaps offering to train staff within the office
to handle specimens appropriately.
Expert systems commonly handle reflexive tests: determining whether
a confirmatory test is needed based on a designated value or result.
For example, at Our Lady of the Lake laboratory, some physicians
want a free PSA test run if the PSA is greater than 2.5 ng/mL. Other
physicians don’t want the free PSA. "Rather than doing it one way
for everybody, we can set up the system to run the confirmatory
based on what the physicians want," Hoglen says.
Free PSA is unusual because there’s not complete agreement on
when it should be used. For most reflexive testing, the medical
staff at Our Lady of the Lake agrees on when a confirmatory test
is needed, and that rule is simply programmed into the system—such
as running a Western blot if the initial HIV test is positive. The
computer immediately decides a confirmatory test is needed and orders
the test on the same specimen. That prevents the problem of forgetting
to run a reflex test and having to ask the patient for an additional
specimen. Another advantage: The expert system notifies infection
control of positive results like HIV or hepatitis B.
"The [expert] rules have really allowed us to streamline our processes,"
Hoglen says. "The computer does it the same way every time, and
you don’t see things changing from person to person or from shift
to shift. It allows us to provide safer, more consistent, and more
At the Cleveland Clinic, expert technology will automatically
order a confirmatory test or will order serial dilution tests after
a positive screening test. One example of a standard reflex order:
In a cholesterol panel, if the triglyceride level is less than 400
mg/dL, the system will simply calculate the LDL value. But if the
triglyceride level is greater than 400, the system orders a direct
analytical quantitation of LDL because the calculation would not
be valid for that level. "The logic to do the calculation or to
order the direct LDL all occur within the LIS," Dr. Henricks says.
Alliance Laboratory Services has used expert logic for years to reflexively
order manual differentials based on instrument results. "We started conservatively,
doing more manual differentials, then gradually modified the criteria to the
extent where it was clear a manual diff would not provide new information,"
A system that can order confirmatory tests also can be programmed
to eliminate what look like duplicate or unnecessary tests, but
this is a step that many institutions are reluctant to take. Even
though the government and other payers would like to see tests curtailed
to save money, "you really are reluctant to override clinicians’
orders," says Rea. But "we do have the computer system eliminate
obvious duplicate orders," he adds. To program his system to eliminate
other types of unnecessary testing, which would streamline orders
to better meet payer and government guidelines, would require lengthy
meetings with clinicians to arrive at the rules, a step St. Vincent
has not yet taken. "As an alternative," Rea says, "our HIShas a
time frame window to alert the nursing staff of some of these possibilities."
Some institutions, however, are venturing into this area. At Our
Lady of the Lake, the expert system will eliminate tests that are
obvious duplicates, such as orders for a Chem 7 panel and a glucose.
"The Chem 7 panel has a glucose in it," Hoglen says, "so the system
will cancel the glucose."
In areas that are less clear, such as a CBC, the system will flag
a questionable test but not cancel it. For example, with most patients,
"a CBC once a day is adequate," Hoglen says. But for patients with
a gastrointestinal bleed or those in surgery, "you may want to do
one every 15 minutes. You have to leave the window open," she says.
If the system detects a CBC that seems unnecessary, it alerts whoever
placed the order with the question: "Duplicate order warning: Order
ACM Medical Laboratory takes a similar approach: alerts rather
than outright cancellation. "If you have a rule that says a manual
differential should be done only once every three days, you set
the system up to alert you if it’s done too soon," Delaney says.
Anytime "we’re looking at restricting tests that a physician has
ordered, we talk it over first with the physician," she adds.
Alliance Lab Services, which includes two large teaching hospitals,
found that it had a problem with duplicate orders, Griffith says.
That’s because, particularly at teaching hospitals, "a lot of different
people are writing orders on the chart." So, working closely with
nursing and medical staff, the laboratory identified tests that
wouldn’t need to be done more than, say, once a week or once every
If the system detects two or more tests of the same type ordered
within the given time frame, "it will cancel the duplicate," Griffith
says. A note is appended to the patient’s chart so that nurses and
clinicians are aware of this step. "Initially there was some hesitancy
to do this," she says, "but it’s turned out to be the biggest non-issue."
The system also detects questionable tests, such as a PSA order
for a female patient, and will display a warning on screen. "I look
upon expert rules as Post-It notes," says Griffith.
Alliance Lab Services kept certain tests, such as blood gases, off-limits
to computer cancellations. "If the specimen is drawn and brought to the lab,
we will do the blood gases," Griffith says. "It isn’t worth arguing over."
Pushing the boundaries
Expert systems have capabilities that are not being fully exploited
yet, not so much because of resistance to computerized medicine,
but because of the time and resources that must be committed to
change work processes. "There’s more we could do," acknowledges
ACM’s Delaney, "but we have to give people time to adjust. You have
to shepherd people through the changes."
Still, some laboratories are exploring the boundaries of what
can be done, even to the point of allowing expert technology to
interpret results. The Cleveland Clinic has its Sunquest system
append comments related to test values. "These are mostly boilerplate
messages," Dr. Henricks says, "and it’s up to the lab to define
what they’ll be."
Our Lady of the Lake Medical Center allows its expert system to
interpret complex findings, such as a hepatitis panel. "A hepatitis
B workup has seven or eight different tests," Hoglen says. "The
system will look at all the results and fire an interpretation."
Hoglen worked closely with pathologists to program the system to
make that determination. "When the system comes up with an interpretation,
it can be modified by the pathologists," she adds, but as their
confidence has grown, "they are basically giving free rein to the
As soon as new computer code is available, Hoglen intends to deliver
drug susceptibility alerts on bacterial cultures to clinicians immediately,
so that a broad-spectrum antibiotic is not used any longer than
necessary. Once laboratory results on a culture are available, "Discern
Expert will notify the physician to switch to a narrow-spectrum
antibiotic," she says. This lowers costs and lessens the likelihood
of resistance. "The doctors have been begging for this," she says.
"We’re pleased to have a computer system that will allow us to do
Working with Molis, Arnot Ogden is in the process of implementing
an oversized terminal in the core lab. The terminal will continuously
track and display the status of stat orders. "The techs will be
able to tell at a glance which tests are approaching the promised
turnaround time of one hour," says Dr. Wilson. "We think that this,
along with autoverification, will significantly reduce the number
of outliers in our turnaround time QA monitors."
Clinipath Labs in Australia uses its LabWizard system to add specialist
pathologist opinions and recommendations to a range of pathology
reports. These specialist opinions draw on present and historical
results, tests in related areas, and clinical notes.
LabWizard is also being used to identify patients who are diabetic.
"LabWizard can determine that test results mean that this patient
is a diabetic," says Dr. Smit, "so it will send an instruction to
the LIS to include diabetes on the list of conditions associated
with that patient. Any future laboratory episode for that patient
is then reformatted in the LIS to deliver results relevant to diabetic
monitoring in a diabetic monitoring profile, complete with comments
and further testing advice."
St. Vincent Health System has been one of the most aggressive
in using expert systems, so much so that it has become a show site
for McKesson, the distributor of its Horizon Lab system. "We have
about 150 rules active now in our lab area," Rea says. "We have
the system doing a wide variety of things, from simple calculations,
reflex orders, tech comments on how to handle abnormal results,
to results interpretations that are canned comments pathologists
would have individually written a few years ago."
Later this year, using an upgraded version of the Horizon Lab software, lab
and pharmacy will be more closely integrated. A prothrombin time or partial
thromboplastin time test result will be forwarded to pharmacy to make a possible
adjustment in the level of anticoagulant. "I will actually have a tie that lets
me see pharmacy records and they can see mine," Rea says.
The future will bring a closer linkage of LIS expert systems with
other departments, especially pharmacy, nursing, and other clinical
areas, and the electronic patient record. Says Dr. Henricks: "If
you do electronic order entry, that’s the point where testing decisions
are being made, and it’s not done with the LIS. But that’s where
expert systems related to test ordering would be most relevant."
At this point, Dr. Henricks says, pathologists and other laboratorians
must understand broader information technology issues if they want
to have an impact beyond the laboratory. The HIS, which governs
the entire hospital or health care system, "is the window through
which tests and specimens come into the lab and results go out,"
he says. Consequently, pathologists should get involved in how HIS
expert systems are programmed. "How are results displayed? How are
tests named and grouped on the screen for ordering? With the explosion
of knowledge in lab testing," says Dr. Henricks, "it’s hard for
doctors to keep up with all the specialized aspects of testing.
The knowledge has to go beyond the LIS."
Karen Southwick is a writer in San Francisco.