We talk to experts about ways in which biomeds can help ensure that their
facilities equipment is safe and reliable and report on some of the consequences of
equipment failure.
Manny Furst points out that 5% to 15%
of problems are no problem found.
Medical equipment reliability is not always a straightforward issue. Medical equipment
can be complex, and the components that factor into equipment reliability are many.
Equipment reliability, contrary to what many may believe, is not directly controlled by
the manufacturer, nor is it necessarily directly related to something the manufacturer
should have or should not have done. User education and training, component reliability,
and other factors that indirectly affect the piece of equipment in question all influence
medical equipment reliability.
Although medical equipment today is probably at the highest level ever of reliability
and safety, one must keep in mind the responsibility of the users, technicians, and
support personnel, in addition to that of the manufacturer.
In general, medical equipment is very reliable. It is a rule of thumb among
clinical engineers and BMETs that 70% to 80% of failure reports cannot be reproduced and
are due to factors other than device failure, explains Jerome T. Anderson, CCE,
principal, Biomedical Consulting Services, San Clemente, Calif. The highest
incidences of reliability problems are when equipment is new and recently installed or
when equipment ages or is mechanically worn and becomes unstable. Failure rates of medical
devices in general are probably much less than 1%. However, lack of maintenance or
performance checks to prevent or detect changes can significantly increase this number as
equipment ages.
The Manufacturers Role
Before the device reaches the market, the manufacturer designs and
constructs the device to be sold. They do a hazard analysis to identify hazards that might
be presented to the patient and what the risks of the device might be compared to the
clinical benefit. Their selection of components, the circuit designs, and the construction
determine its intrinsic reliability. The company must focus on these three factors to
maximize the reliability of the device, explains Marvin Shepherd, PE (safety),
FACCE, DEVTEQ Consulting, Walnut Creek, Calif. When the studies are complete, they
are submitted to the US Food and Drug Administration for approval and, if approved, [the
company] can now manufacture the device for sale. Once the device is in operation in a
hospital, the BMETs/clinical engineers are responsible for maintaining the reliability of
the device through preventive maintenance and corrective maintenance.
According to Anderson, liability exposure can be controlled by ensuring that the
designers of internal systems understand the application and consequences of failure.
While many people can design a motor or an electronic circuit, many engineers are simply
asked to design a device or portions of it with little or no understanding of its
application.
Shepherd explains that all medical devices are designed to deliver at least one
clinical benefit to a patient, but the devices cannot work alone and need others to help
them deliver the benefit. The patient, device, facility, and operator all make up an
environment in a minisystem that delivers the clinical benefit. Any one of
these components in the minisystem can fail and prevent the device from delivering its
clinical benefit. When biomedical technicians and clinical engineers investigate a mishap
with any medical device in their facility, they must thoroughly investigate each component
in the minisystem to determine which one(s) contributed to the problem. Shepherd stresses
that the hospital or health care facility is responsible for all the components of the
minisystem, and the clinical engineer and BMET are responsible for the device or
technology itself.
The manufacturer, then, is the first in the chain of ensuring medical equipment
reliability. It has a responsibility to manufacture a fail-safe design, using high-quality
components and materials, and provide technical and end-user training and/or
certification, and well-written instruction manuals. The manufacturer and the FDA both
must ensure that the product meets their specifications for design and other standards,
such as those of the International Organization for Standardization. The manufacturer also
can help maximize product reliability by providing easy access to replacement parts and/or
repair services, and technical support solutions, according to Manny Furst, PhD,
president, Improvement Technologies LLC, Tucson, Ariz.
Look at the system, including the environment, user, and maintainer, as well as
the device itself. Understand that the health care environment can be very tough on
equipment, and understand that some of the off-the-shelf commercial equipment,
such as personal computers and printers, are not made for a harsh environment like health
care and will not be as reliable, says Ted Cohen, manager of clinical engineering,
University of California Davis Medical Center, Sacramento. Its the
manufacturers job to assure that the appropriate operating system, virus scanner,
etc, is specified for a particular computerized medical device application. Manufacturers
need to take responsibility for all equipment provided, including the off-the-shelf
hardware and software. They also need to provide adequate documentation and training and
test, test, test.
Anderson adds that long-term testing under conditions that simulate or overstate the
conditions of use can be an effective way to detect and correct possible equipment
failures. User-friendly designs are also important, in order to reduce the possibility of
human error in device operation.
The Purchasers Responsibility
Responsibility for the hardware and software usually falls on the clinical
engineering team and BMETs. They are often responsible for much of the prepurchase
evaluation of the equipment. This evaluation should be conducted within critical clinical
processes in the ways that the specific hospital implements the equipment, especially with
inexperienced staff, evening and night shifts, travelers, and float staff, Furst suggests.
He also advises consulting other users of the same equipment with similar clinical goals
and procedures about their experiences with the product to find out if they would
recommend it.
It has to be a team effort to select the application that best fits the needs of
the institution, says Bruce A. Maden, CBET, director of operations, MedEquip
Biomedical, Miami.
Anderson agrees that the purchaser has a responsibility to ensure that the
institutions requirements match the devices applicability.
The purchaser has a number of responsibilities to ensure that the devices are
appropriate for the intended application, do not have a high failure rate, and meet the
needs of the patient and staff, says Anderson. It must evaluate the ability to
maintain and repair the device, where applicable, whether this is done in-house or by
outside services. The purchaser also must ensure that a proper operating environment will
be provided for the device to prevent malfunction or failure due to operating-environment
factors, such as heat, humidity, incorrect voltage, or inadequate water supply, and make
sure that the personnel responsible for installing, operating, and maintaining the device
have the appropriate training and credentials.
The purchasers level of knowledge is important, notes Cohen. The purchaser
needs to understand what they are buying and make sure their planned use is consistent
with the manufacturers design and the purchasers work flow and
culture. The purchaser needs to share the responsibility of training the
end-user on the use of the device, he says.
To ensure that the device is being used properly, and to its maximum efficiency and
potential, the engineers and BMETs have to know how to use it as well as, if not
better than, the end-user, says Maden.
If there is a problem with the device, especially with the end-user, it is the biomed
departments responsibility to evaluate the situation and note if the device is too
difficult to use, or if the users need more education and training to operate it properly.
According to Maden, problems with medical equipment must be documented precisely to
determine the best solution. Often, arranging for another round of training with the
devices manufacturer will help solve end-user problems. He believes that
user/operator issues, rather than outright device failure, are the most commonly reported
problems with equipment reliability. Computer failures are the second most common reasons
that he sees equipment fail, since nearly all medical devices today depend on computer
systems.
Overall, the failure rate of medical equipment today is very low, notes Maden. In
my experience, education is the biggest problem. Look at the documentation and see how the
user is interfacing with the equipment.
Furst agrees, explaining that in his experience, 5% to 15% of reported problems were
no problem found, in other words, probable user error, and an additional
smaller percentage were confirmed operator error.
Once the device is purchased by the hospital, the manufacturer is pretty much out
of the picture, says Shepherd. The hospital is responsible for providing the
education and training of the operator, the education and training of the BMETs and CEs,
the gases and electricity, and the other minisystems that are used in the patients
environment. According to Furst, some hospitals should also provide education and
processes to reduce accidental damage and abuse of equipment. He has seen these account
for as much as 5% to 10% of equipment problems and repair costs.
The purchaser will often be placed in the position of defending an insurance claim or a
lawsuit in the event of a major injury or death related to the use of a medical device,
says Anderson. This will affect them not only monetarily, in terms of investigation and
defense costs, but also through lost income from a device being unusable for a period of
time, liability insurance premium increases, and possible loss of reputation and business
in the community they serve.
The main thing [that] I believe would improve equipment reliability and
performance is the human factorimproving the training of the user of the
equipment, says Anderson. I believe there is a significant relationship
between the users knowledge and the results obtained from a device that is of more
importance than the issue of hardware failure.
CEs and BMETs Are on the Front Line
The clinical engineer is usually responsible for ensuring that there is
adequate support for the equipment in terms of proper installation where required, user
training, service-technician training, adherence to scheduled maintenance, and efficient
and effective repairs. The clinical engineers liability primarily lies in the area
of inadequate management of the support needs of the device. Failure to properly maintain
is a frequent allegation made by plaintiffs attorneys, says Anderson.
The BMET has liability for the hands-on maintenance and repair of a device. If this
person is not adequately trained or experienced in maintenance and repair of the device,
their liability exposure is significantly increased. If an error is made in the
maintenance or repair of a device resulting in a poor patient outcome, responsibility will
be placed with the technician who last serviced, or forgot to do maintenance on, the
device. A major area of liability for technicians is failure to document the work done, as
undocumented work cannot withstand the attack of a lawsuit in which failure to properly
maintain or service a device is an issue.
Reliability Affects Liability
Once in place, equipment affects liability by its performance and failure rate,
acknowledges Anderson.
If performance degrades over time and does not provide the proper results for the
patient, the purchaser will share liability for inadequate results with the manufacturer
and the party maintaining the equipment. There will be liability for purchase and design
of unreliable devices, failure to maintain them, and failure to replace unsafe equipment
that may have a negative impact on patient care or employee safety, Anderson says.
As employees of a corporation, the clinical engineer and BMET will generally be
protected from direct legal action, but if it can be demonstrated that a serious error was
made or the person was not qualified to repair or maintain the equipment, the person may
be named individually in litigation, according to Anderson. They may also become involved
in legal depositions and/or disciplinary action by their employer.
In the matters I have been involved in, the main reasons for liability suits to
be brought are user error, incorrect setup, or inappropriate application of a medical
device. While design defects are a common ground for bringing a suit, these are often not
upheld, says Anderson. Off-label use by a physician is a more frequently
brought charge, with consequences primarily for the physician, assuming the manufacturer
has done a good job of defining the intended applications and contraindications for the
product. The consequences I have seen result from liability claims or litigation include
monetary awards from $10,000 to $10 million; removal of a product from the market;
physician or caregiver reprimand; updates, changes, and additions to caregiver and
facility policies and procedures; criminal investigations; investigations by state health
departments; and termination of employees for cause.
The consequences of equipment failure can range from minimal to catastrophic, such as
patient injury or even death. The users and maintainers often suffer emotionally from the
results of equipment failure, especially if they were serious. Negative publicity
resulting from equipment failure can impact the reputation and financial health of the
organization, notes Furst.
The consequences can be large to all if there was a patient injury. Otherwise,
the consequences are primarily economic and dependent on the cost of the failure in terms
of lost patient revenue as well as the cost to repair or replace the device. Of course to
the manufacturer, if the problems are chronic or not handled well, then the largest cost
may be in lost future sales, says Cohen.
Does PM Affect Reliability
One area of debate over the past several years has been preventive maintenance
(PM), But now there are questions about PMs necessity, appropriate intervals, and
long-term impact. For a long time, PM procedures were the cornerstone of any biomed
program.
A number of years ago, I was asked to sit on a focus group involved with one of
the infusion pump manufacturers. They shared with us that in the design criteria, the pump
was to have a mean time between failure of 60 months. Now why in the world would I perform
any maintenance on such a device if it was designed for a 5-year (on average) time between
failure? asks Ira S. Tackel, clinical/biomedical consultant, Fort Washington, Pa,
and former director of the biomed program at Philadelphias Thomas Jefferson
University Hospital.
But then we looked, retrospectively, at failure data of infusion pumps
specifically. What we found was not surprising, but was ample justification to change the
way we looked at performing PM. A very small fraction of all of the PM performed on
infusion pumps actually identified latent failures in the device. Therefore, we were
performing busy work on the vast majority of pumps where time and again, they were testing
as no failure. One could also argue that it is the responsibility of the
clinician to verify the performance of the device before ever placing it on a
patient.
According to Tackel, unless one is performing meaningful PM on a device, there is
little in a preventive mode that one can do to increase reliability of the device.
There is a fundamental difference between changing the oil in your car at regular
intervals, which should increase the reliability and longevity of your car, and something
similar in a purely electronic device, says Tackel. Of course there are
exceptions to the rule. When we are talking about an electromechanical device, such as a
dialysis machine, there very well may be aspects of preventive maintenance that do indeed
increase the reliability of the device. And when we speak of high-end equipment, such as
CT or MRI, there is [definitely] value to routine PM.
Laura Gater is a freelance writer for 24x7.
Correction: Richard J. Lee, featured on the cover of the January
issue, is an employee of Technology in Medicine, Holliston, Mass.