Nobody likes to guess wrong when the stakeseither in patient care or health
system expendituresare high.
Thats one reason biomedical and clinical engineering departments often are asked
to help devise tests to evaluate one brand of pump, monitor, or other device against those
of competing manufacturers.
Organizing and administering these equipment evaluations is complex, so much so that
hospitals and health systems often find ways to make purchasing decisions without
conducting them.
Clinical and biomedical engineering departments often take the
lead in organizing and coordinating clinical trials and comparative evaluations, which,
though used to save money, can be costly themselves.
Still, conducting evaluations can yield useful information, such as estimates of the
learning time that will be required to operate equipment and subjective staff reactions to
equipment. Also, departments that buy-in to a testing effort cannot really complain if
their original equipment favorites dont make the cut when judged by a panel
representing the whole institution.
When equipment is tested in a simulated environmentsuch as running a pump that
feeds intravenous (IV) fluid into a jar instead of a patientthe trial is called a
comparative evaluation. When the pump is feeding IV fluid into a patient, the test becomes
a clinical trial. A single testing program often involves both of these elements.
Cost Compression
Sometimes, equipment evaluations are relatively simple.
Caroline Campbell, CCE, is senior project manager in clinical engineering for Clarian
Health Partners, a hospital system headquartered in Indianapolis.
Campbell is currently involved in a clinical trial of sequential compression devices
(SCDs). SCDs are small pumps attached to leg sleeves that compress the legs of patients at
risk of forming deep leg vein blood clots. The sleeves squeeze the leg to keep blood
from pooling in surgical patients or the bed bound, Campbell says.
Nearly all evaluations and trials are conducted for one of two reasons: 1) a new,
possibly cheaper, or better, device has come on the market, or 2) an institution is having
problems with its current device and wants something that may alleviate the problems.
Clarians trial with SCDs is being conducted for both of those reasons. The
current techology is no longer supported by the manufacturer, thus forcing a change in the
technology used. Clarian, says Campbell, had been using many thigh-length compression
sleeves that cover most of the leg with the older technology. But physicians think that
sleeves that come only to the knee work just as well at preventing leg vein thrombosis and
are less costly.
So, Clarian has put 100 of the knee-length SCDs from a single vendor on trial on live
patients in a designated mix of medical and surgical units.
The trial will continue for 1 month, Campbell says, and then an evaluation committee
will look at the results. The committee will use an evaluation tool, as
Campbell calls ita checklist that ranks factors like ease of use and acceptability
in the clinical environmentto rate the leg-sleeve pumps. Based on the outcome of the
evaluation, Clarians capital committee will decide whether or not to purchase the
new pumps and sleeves.
Campbell says clinical engineerings role in the SCDs evaluation was to get
the devices ready for deployment. After the trial, she will make sure the devices get sent
back to the manufacturer. Then, as a member of the capital committee, she will join in any
decision to purchase the new SCDs. If they are purchased, clinical engineering will get
the new ones deployed.
A major factor in any technology decision would be cost, Campbell says.
We want a product that will meet the clinical needs, Campbell says.
But, saving money is a frequent objective. I dont think we make any decisions
without knowing the monetary situation.
Taking the Vendors Pulse
Clinical and biomedical engineering departments often are not the ones to
initiate comparative evaluations and clinical trials, but they do become the lead
departments in organizing and coordinating such evaluations.
Barry Bruns is director of biomedical engineering for the Health Alliance of Greater
Cincinnati, a joint venture between six area hospitals. Bruns says his group will often
check with equipment-rating agencies and other hospitals when evaluating equipment, but it
also does its own evaluating.
Recently, the Alliance tested pulse oximeters. To conduct its evaluation, it chose
three leading vendors and then compared those three in both simulated and clinical
conditions.
New oximeter models, says Bruns, have introduced technology to get rid of motion
artifacts (patient movement) that sometimes skew blood-oxygenation readings.
To test the accuracy of these new models, simulators were used. To test factors like
ease of use as well as reliability and accuracy, the Alliance resorted to clinical trials,
comparing the three brands of oximeters in use-trials on patients in all six of its
hospitals respiratory departments.
Respiratory therapists developed a one-page checklist as an evaluative tool, Bruns
says. The devices were tested for both short-term use, which might be minutes, and for
more long-term use on sleeping patients, which went on for hours at a time. In the end,
Bruns says, a clear winner emerged: a device that was both smaller and easier to use than
the competing devices.
Bruns says some vendors were more responsive than othersanother important factor.
If theyre not responsive on trial, theyre not going to be responsive
when we own the device, and some were more responsive to the therapists
questions.
The Alliance also ran cost projections on each device, of not only the cost of the
oximeter itself, but also of the accessory probes that fit on patients fingers.
They break, and theyre expensive to replace, Bruns says. Each oximeter
cost about $2,000, and probes ran from $100 to $250. The favored unit survived the cost
analysis and was the device chosen. We are only replacing about 10 for now, but in
the future well do another 20 to 50, Bruns says. The Alliance will save
money by standardizing, and then the training needs of the staff will go down.
Multi-Vendor Quality Assessment for Safety
Patient treatment errors are costly, and nowhere do they occur with such
frequency as in the delivery of drugs to patients. In the sometimes stressful conditions
at a hospital, medication mistakes are not difficult to make since they may involve
nothing more than an errant keystroke.
Glenn Scales, CBET, is assistant director of the clinical engineering department at the
Duke University Health System in Durham, NC. It includes the main campus
medical center and two other hospitals.
Dukes clinical engineering department is routinely involved in making
product decisions, and that includes overseeing evaluations or clinical trials,
Scales says. Late in 2003, Duke undertook an evaluation of infusion pumps.
Infusion pumps, which control the delivery of IV medications to patients, can be
programmed to deliver many different drugs in different circumstances. A misstep in
programming can lead to a drug-delivery error, sometimes with fatal consequences for the
patient.
If the intent is to deliver 8.5 milliliters per hour and the nurse inadvertently
puts in 805, you could deliver a lethal dose, Scales says. An equally egregious
error might be made by misentering dosage per body weight, he adds.
Newer infusion pumps are designed to prevent these sorts or errors by signaling when a
prescription appears to be out of bounds, Scales says.
For us, infusion pump errors had become a fairly big problem, Scales says.
To address that concern, Duke tested and compared the pumps from three leading vendors.
After devising a testing paradigm that would yield a measurable result in a fairly short
time, volunteer clinical staff were chosen to act as equipment evaluators.
Each device was to be evaluated by 12 different evaluators, Scales says.
Working with pharmacology and clinical departments, Scales and his team identified four
typical patient protocols, such as the delivery of an anesthetic, anticoagulant, or
antibiotic to a patient, who might be identified as an 18-year-old male or a
17-year-old female. For each patient protocol, the team then identified 29 documentable
steps in the drug-delivery process. Each of these steps was to be performed by the
evaluators. The volunteer evaluators were chosen to represent a breadth of skill levels,
Scales says.
Two patient rooms were set aside for the two-stage tests. In one room, a team of
trainers representing a vendor would spend up to an hour teaching the evaluators how to
use their particular machine. In a second room, from which vendors were barred, the newly
trained evaluators were put through the 29 steps of each designated patient protocol. They
might be asked to respond to an alarm on the machine or to load new tubing, Scales says.
Each of the 29 steps was given a rating, based on its criticality and complexity. All of
this was done under simulated conditions with the infusion pump feeding the IV solution
into a beaker, he adds.
As the evaluators were completing these tasks, they were themselves being watched and
graded by Scales and four other superevaluators.
At the end, for one vendor we would wind up with 12 evaluation scores. If a nurse
had done everything perfectly, the best score would be 100, Scales says. Each
evaluator would be scored by the superevaluators. When the process was completed, each
vendor was given a composite score based on the performance scores of the 12 evaluators.
The clinical evaluators were also asked to rank the machines on a number of factors,
including usability and patient safety. These rankings were also given numeric values and
were compared among vendors. The clinical evaluators were also asked to make subjective
comments, and these, too, were critical to the evaluation process, Scales
says.
By using this strict comparative format, Duke completed its simulated testing in 6
days, a process that might otherwise have taken up to 8 weeks per vendor in clinical
trials, Scales says. He says his team had expected to eliminate one of the vendor
candidates in this process and then clinically test the remaining two pumps against each
other. Instead, he says, one pump emerged a clear winner in the simulated trials. That
pump was then placed in clinical trials on patients in four operating rooms to make
sure we got it right, Scales says.
From start to finish, the process took 6 months. Scales says hes not sure how
much the evaluations cost Duke, not to mention the vendors. Youre talking
thousands of dollars in staff time. Eventually, he says, Duke may deploy as many as
2,500 of the new pumps at a cost that might approach $5 million.
He says the evaluation schematic worked so well that the university is considering a
similar format to evaluate another tricky piece of equipment: patient ventilators.
Saying No
A comparative trial may not always be the way to go, however.
John Doyle, BMET, is assigned to handle new equipment for the Veterans Affairs (VA)
Medical Center in Portland, Ore. Doyle says the Portland VA was intent on changing its
physiological monitors, but the costs and staffing requirements left little room for
holding comparative trials. So, Doyle and the VA staff contacted vendors, other VA
hospitals, and non-VA end-users of the devices, and selected a new monitor that way. Since
all the monitors would be linked in a network where each patients physiological data
could be tracked from a central location, they would have had to have been linked in a
test to be effectively judged.
It would have been too resource-intensive to set up a trial, Doyle says.
We would have had to pull network cables. We ended up doing site visits and had
different people from our team call references on both the user side and the maintenance
side. We ended up going with a new vendor, and we bought over $2 million worth of the
monitors, close to 100 of them.
Doyle is an advocate of evaluations whenever they are feasible. In the past, he has
helped coordinate evaluations of infusion pumps and electrosurgical units. In both of
those cases, vendor choices were altered by the testing, he says. But he says there is
frequently a political motive for doing comparative trials.
If a device shows up in your department and you havent been involved in the
decision-making, you may have an immediate resentment of this device despite its features
and ease of use. But if you have buy-in on a new technology, thats worth
something.
Like the others interviewed for this story, Doyle says the participation of biomedical
or clinical engineering departments in comparative trials can play a key role
in how effective the trials are.
We look at how maintainable and reliable something is, but when we do that, we
try to look through the eyes of our users. If we pick a dog, it will impact our role as
well. Biomed has to put on the users hat. 24x7
George Wiley is a contributing writer for 24x7.