For many years, a transesophageal echocardiogram simply involved the insertion of an endoscope through the mouth and down the esophagus where the head of the device would rest, right behind the heart. While providing clinicians with clearer views of the heart compared to transthoracic ultrasound, the procedure carried additional risks.

If the TEE probe had a bite hole, an electrical leakage could occur. The onset of an incident like this so close to the heart put the patient’s life in danger. To prevent this from happening, the Intersocietal Accreditation Commission issued a new standard in 2015 concerning Adult Transesophageal Echocardiography Testing, whereby the structural and electrical integrity of the transducer must be verified between each use with an ultrasound transducer leakage tester.

“The IAC came out and said you cannot use that probe until it’s been electrically tested and proved to pose no harm to the next patient,” Ken O’Day, vice president of sales and marketing for BC Group International Incorporated, a company that designs an electrical leakage tester for this purpose, told HCB News. “That’s moved leakage testing from its traditional place in the biomed arena into the ultrasound and cardiac departments or, depending on the hospitals, anyone else who is actually cleaning the TEE probes between tests. “

The IAC mandate illustrates how the development and use of testing equipment — just like medical devices themselves—are continuously changing. Also like medical systems, such equipment is subject to various standards and regulations from formal agencies, manufacturers, providers, hospital biomed groups, government inspectors, and medical physicists.

More sophistication calls for new test solutions
As X-ray systems have grown more complex, so too has the test equipment used to validate them. One such evolution has been the development of solid-state multi-sensors for measuring X-ray beam properties.
"In the past, there would be a single sensor placed in the beam, and you would measure the strength of its response," said Curt Harkless, president and CEO of Radcal Corporation. "You would manually insert filters into the beam at increasing levels of thickness so that you could characterize the X-ray spectrum. Now, solid-state multi-sensors have multiple sensors with filters in between them so that with a single exposure, you can fully characterize the X-ray beam."

Improvements have also been seen in electrical surgical units that use sophisticated pulsed waveforms that first and second generation ESU analyzers cannot read. As a result, many require a one percent accurate instrument for generator testing, which has led to equipment six years and over that can measure at rates of 5-15 percent accuracy becoming obsolete, according to O’Day.

“Devices have become smaller in size, increasing portability,” says Brittany Schmidke, national business development manager at Rigel Medical. “There is also connectivity with CMMS programs and between the testing equipment and the device being tested. Prices of the devices have actually come down. Touch screen is ever-evolving, and there are now color screens.”

Harkless notes that changes in test equipment, especially within X-ray testing, stem from greater pressure on quality assurance specialists “to get in, get the job done, and get out.” Adding that, “anything that saves time is a premium in the industry right now.”

While most devices have evolved to the point that older test equipment can no longer provide the functions or accuracy necessary to test these more advanced devices, some types of solutions can still be sufficiently tested with equipment going back decades.

“I used to sell EKG simulators 35-40 years ago,” said O’Day. “That simulator back then will still simulate an EKG complex today just fine, but ESU generators, anesthesia monitors, defibrillators and other medical devices have evolved beyond the capabilities of older test devices.”

Different paths toward equipment validation
The guiding principle for development and efficient use of test equipment is the ability to test and repair whatever the medical device industry creates, says Jerry Zion, global training manager for Fluke Biomedical. For patient monitors this means sending patient-like signals into the medical device just the same as a patient’s real vital signs would come in during clinical use. These are called simulations or functional test information.

Increasingly, many facilities are opting to construct biomed teams to assess equipment in-house. While this requires an investment in tools and training, it removes the expense and wait-time that can be associated with depending on manufacturers for testing and repairing equipment.

“Testing and databasing test results day-by-day and year-over-year enable department staff to get a feel for the medical devices in the inventory of the medical facility and for identifying when failure rates rise. As a result, they can find problems earlier, while they are less expensive and easier to repair,” said Zion. “That makes sure that critical medical devices — especially those of which are small in numbers — are available and ready to use. Otherwise, the hospital loses money and the patient can sometimes become sicker or lose their life due to the device being broken or unavailable to provide them with treatment.”

But constructing such in-house groups can be costly. For some providers, particularly smaller ones, having the OEMs conduct testing makes more sense. Göran Zelander, senior product manager for RaySafe’s diagnostic X-ray portfolio, says the right choice on who conducts testing has a lot to do with the type and complexity of the device.

“If you look at more expensive X-ray environments, like computed mammography labs or interventional suites, it’s going to be almost entirely service contracts handled by the manufacturer because of the complication level and how complex the equipment is, and the knowledge required to test it,” he said. “Traditional X-ray and mobile machines, which you have more of, can sometimes be serviced more by in-house engineers.”

Karl Ruiter, president of Pronk Technologies, says the decision to test equipment in-house versus having the manufacturer do it can be based on a wide range of factors.

“Maybe the learning curve on a particular device is just very steep, or there may be expensive specialized tools, or the manufacturer does not supply parts or the necessary information for local service,” he said. “Possibly the biomed shop is just looking to outsource some work so it does not have to grow its team. Also, anytime there is a warranty repair required, it makes sense to look at having the manufacturer take care of it. It’s also true that knowledgeable biomedical engineers, on-site, who are seen as part of the team, can bring a lot to the table.”

Abiding by standards
From hospital specifications to ISO guidelines, testing equipment must adhere to a number of standards. Some are required by law while others are not mandatory but strongly encouraged. These guidelines change as technology becomes more sophisticated, with automation, cybersecurity and AI bringing about new advantages and considerations to entire segments of the equipment market. More broadly, regulation is guided by quality of care, user experience, and the diversity of medical equipment needs worldwide.

“If you look at a global level, there will be a lot of testing needs in developing countries such as Brazil and India,” said Zelander. “China is well developed, but from an X-ray equipment viewpoint, it’s very limited in the number of tests per X-ray machine, compared to the U.S. or Western Europe.”

According to Harkless, cost and efficiency demands will lead to more integrated quality assurance processes. Over the next five or ten years, that means testing equipment will move away from the larger instrument models we see today and toward smaller, less expensive solutions.

“What we try to do with the testing equipment we build today, is include some kind of an upgrade path, so that as new medical equipment and requirements are introduced, the existing test device can be upgraded to meet the new demands,” said O’Day. “This saves the end user from having to purchase a completely new test device to stay compliant.”

Zion notes that commercial technologies are influencing standardization around testing equipment, especially around the transmission of information to the cloud. Despite these big-picture changes, the objective behind testing equipment remains the same.

“Our aim is to help reduce risk of injury or death to the patient through our everyday heroes, who are biomedical engineers and technicians that work in hospitals, manufacturing, design of medical devices and in field service,” he said. “Detect problems early instead of letting failures happen during clinical use.”