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 Manufacturer’s 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. “It’s the manufacturer’s 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 Purchaser’s 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 institution’s requirements match the device’s 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 purchaser’s 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 manufacturer’s design and the purchaser’s 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 department’s 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 device’s 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 patient’s 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 factor—improving the training of the user of the equipment,” says Anderson. “I believe there is a significant relationship between the user’s 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 engineer’s 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 PM’s 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 Philadelphia’s 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 24×7.
Correction: Richard J. Lee, featured on the cover of the January issue, is an employee of Technology in Medicine, Holliston, Mass.
