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Scope Leak Testing


Endoscopes are complex devices that mix mechanical, illumination, optical and video elements, none of which react well to fluid. As a result, endoscope leak testing is a crucial part of proper scope cleaning and disinfection, but oftentimes, it is done improperly or not done at all. There are both manual and automated forms of leak testing. Regardless of what type your facility uses, it must be done.

Costs associated with scope repair are astronomical. And, not surprisingly, the greatest costs are often associated with fluid invasion — the disastrous result of not detecting a leak in time.

Fluid damage triggers over half of total endoscope repair costs. Moisture can cause damage as soon as it invades the scope. And the longer fluid remains undetected and unaddressed, the greater the damage to the instrument.

Medivators scope reprocessor with automated leak testing

Flexible scope manufacturers, government health agencies, and organizations related to the gastroenterology industry all recommend that a flexible endoscope be leak-tested after every procedure. These organizations identify leak testing as a core element in their multi-step reprocessing guidelines.

Fluid invasion has become so common that some manufacturers and repair companies even recommend two leak tests between procedures.

In a guide presented by Instrument Specialists, Inc., the company discusses the problem of fluid invasion.1

When troubleshooting common flexible endoscope problems, they say, fluid invasion in particular requires immediate identification and repair by a trained technician.

If a fluid invasion goes undetected, signs of it when using the scope include the following:

  • Image stains
  • Foggy images
  • Electrical malfunction

“If a leak is detected, remove the endoscope from the testing water to prevent further damage,” the repair firm recommends. “It is very important that the endoscope be immediately taken out of patient service until it is repaired by a qualified technician.”

In the Standards of Infection Control in Reprocessing of Flexible Gastrointestinal Endoscopes, by the Society of Gastroenterology Nurses and Associates (SGNA), the society recommends that leak testing occur before the scope is submerged.2

“The leak test is done before immersion of the endoscope in reprocessing solutions to minimize damage to parts of the endoscope not designed for fluid exposure,” the SGNA recommends. “Leak test the endoscope following manufacturer’s instructions.”

There should be a copy of the manufacturer’s instructions readily available in any area of the hospital where endoscope reprocessing is performed.

When manual leak testing is done, the SGNA recommends, “Attach the leak tester and pressurize the scope before submerging it in water. Refer to specific manufacturer’s instructions to determine if it is necessary to remove detachable parts before leak testing. With the pressurized insertion tube completely submerged, flex the distal portion of the scope in all directions, observing for bubbles. Submerge the entire endoscope and observe the head of the scope, the insertion tube, distal bending section and the universal cord for bubbles coming from the interior of the scope. Follow the endoscope manufacturer’s instructions if a leak is detected or the endoscope appears damaged.”

Infection Control Considerations

From an infection control perspective, proper leak testing is one of the most important reprocessing steps. Cross-infection is a risk if a leak is left unchecked. Retained organic soil can inactivate germicides. It can also prevent contact of the germicide with potentially contaminated surfaces. Both circumstances create an infection risk.

If a scope has a leak, fluid, biologic materials, and biofilm can collect in areas that cannot be adequately cleaned and disinfected. Endoscopy departments then increase the risk of having scopes that are already colonized with bacteria and viruses when they are used on the next patient.

Additionally, if a leak is undetected, and the endoscope is then cleaned and disinfected, that means that cleaning fluids and disinfection fluids have access to the areas that the leak opens to. Fluid is not only going where it’s not supposed to, but it may even increase the size of the leak, and damage the internal mechanical and electrical elements of the scope. If the size of the leak is increased, the chance of pathogens entering other areas of the scope is amplified.

In An Outbreak of Bronchoscopy-Related Mycobacterium Tuberculosis Infections Due to Lack of Bronchoscope Leak Testing, epidemiologists discussed an outbreak of tuberculosis (TB) that occurred when a hole in the endoscopic sheath allowed access to a space that was difficult to clean and disinfect.3

As a result, five patients who underwent bronchoscopy had M. tuberculosis positive bronchial washing cultures. Further investigation revealed that leak testing, a critical step in bronchoscope reprocessing, was not routinely performed at this institution.

“Our study shows how important it is to adhere to the reprocessing procedures specified by bronchoscope manufacturers,” the authors write. “This includes conducting leak testing after each procedure. If a leak is detected, the bronchoscope should be sent to the manufacturer for repair or replacement.”

Common Problems

In an article on repair costs related to scope leaks, James M. Berklan reports that flexible scopes are being used longer and harder. The cause of most damage, however, is not from overuse, but from fluid invasion.4

A common mistake is waiting until after disinfection or sterilization to perform leak testing. Performing the leak testing step out of place means that there is a much greater chance of fluid invasion once the scope is subjected to disinfection.

Verimetrix offers the Veriscanautomated leak tester.

Another problem is reprocessors thinking that once they detect fluid inside the scope, all it needs is to dry out. Instead, the "guts" of the scope should still be inspected to ensure that the inner mechanical and electrical structures are undamaged, and that interior lubricatns have not been affected. Other people might use waterproofing tape to protect the scope, although it is not intended for this purpose, and is certainly not recommended by the scope manufacturers. Nor is using tape or glue. Delaying repairs with stopgap measures may harm more than it helps.

Because flexible endoscopes can cost $20,000 apiece, hospitals and other medical facilities should be investing great effort into keeping them in one piece. Small repairs can be just a few hundred dollars, while a disastrous fluid invasion could ruin the scope and require a rebuild, the costs of which could exceed half the price of a new instrument. And ultrasound endoscopes ring in at over $80,000, so costs to repair their delicate inner workings could be even greater.

Education is another issue. Endoscopes are cleaned by endoscopic technicians, endoscopy nurses, or staff in the facility’s central sterile or sterile reprocessing department. Endoscopy staff may not disinfect items as frequently, but may be well aware of gastroenterology societies’ recommendations for cleaning and leak testing. Sterile processing staff may be well-versed in cleaning and disinfection, but not fully instructed as to the importance of leak testing. And frequent turnover in this department means that there is often insufficient time for proper training. Providing these two disparate groups with all the information they need to properly clean and disinfect endoscopes is crucial.

There are additional problems that may interfere with proper leak testing — namely, distractions. For the endoscopy staff, there are distractions in the form of patients, paperwork, physicians, and administrative work. For central sterile, it’s a different challenge.

There is a lot of pressure on these technicians to handle the scopes very carefully, points out Terry Bader, CEO of Verimetrix. And because of the speed of the work in the reprocessing area, many instruments are cleaned together, but scopes should be cleaned separately from other tools. Technicians are encouraged to hurry, to get the instruments in and out of the sterile processing department (SPD), because physicians or operating room nurses are frantically calling for the tools they need.

“That room is very hectic; there’s a lot of activity and things move very fast,” Bader says. “There are many hard surfaces and sharp objects, and that’s a bad combination for handling an extremely delicate instrument. The doctors are also moving fast, and if they’re not very careful with these instruments, damage can be caused during procedures. The incidence of leak damage per procedure is pretty high.”

Automated Options

Medivators Reprocessing Systems, a division of Minntech, offers the DSD-201LT Endoscope Reprocessor, a dual-scope system that comes with an optional automated endoscope leak testing capability. There is also a single-scope model, the SSD-102LT Endoscope Reprocessor, which has the same optional add-on for leak testing. The dual basin can save time for reprocessing technicians by allowing them to reprocess (and leak test) two scopes at a time — and scopes can be added to the machine at different times. The leak testing occurs while the scope is coiled inside the reprocessing machine, so although the distal tip and body of the scope cannot be manipulated, techs using the system often perform a manual leak test before placing the scope inside the machine, says Thomas Arcand, MBA, Medivators product manager.

“To use this system, the technician loads the scope into the machine after checking the concentration of the disinfectant, then attaches the necessary hook-ups, verifies the disinfectant temperature, and selects the appropriate reprocessing program of the nine offered,” Arcand explains. The technician enters identification data, including which basin is being used for reprocessing, the scope number, operator ID, patient and physician data, then presses the start button. If the leak testing option is selected, the reprocessing cycle will not begin until after a 40-second leak test is performed.

The dual basin option alleviates endoscope bottlenecks, when a number of scopes pile up and wait to be reprocessed and leak tested, by allowing simultaneous or separate cycles in the two compartments. Audible alerts notify a technician if there are deficiencies in the reprocessing cycle, and a log printout after completion of the cycle notifies them if there was a leak test failure. Not only that, but “the automated system assures patient safety and facility compliance,” Arcand adds. With a documented printout of all cycle data, department supervisors can be assured that leak testing has actually occurred.

Verimetrix also offers an automated service for endoscope leak testing. The Veriscan™ Automated Endoscope Tester was designed to remove the human element from testing, as there are so many potential ways to err when manually leak testing an endoscopic device.

The Veriscan was designed to automate the leak-testing process. “All the research we did indicated that technicians were going to miss about one-third of the leaks,” Bader reports. “Those all result in fluid getting inside the scope, and, consequently, in very expensive repairs.”

The Veriscan has been shown to detect 98 percent of leaks and fluid, so the accuracy of leak testing improves dramatically. “The Veriscan incorporates a microprocessor, so the data from the leak tests is captured. At the end of the day, the nurses can push a button on the screen to verify all of the testing, allowing for the ability to confirm that best practices are being followed,” he adds.

The data captured by the automated system is not only intended for confirmation and accountability. If damage is detected in the scope, the technician can print out the result of the leak test and send it out with the scope for repair, giving the repair technician information that can dramatically speed up the process of bringing the scope back to performance levels.

The data capture also enables the healthcare facility to track how many scopes are tested, which scopes fail — or which fail most often. It also can track if certain scopes are used more than others, and endoscopy staff members can make an effort to equalize the use of each scope in the department. It is common for a few scopes to be used most frequently, while the remaining scopes receive only occasional use. If certain scopes are over-used, that can exacerbate the damage to them.

Verimetrix has analyzed the costs of repairs after using Veriscan compared to the costs of repair after using manual leak testing, across thousands of procedures. “We currently perform over 100,000 tests a month,” Bader reports. “We now have data that examines scope repair costs six months prior to Veriscan and six months post-Veriscan. We have found that in any hospital experiencing $2,000 a month in scope repair bills or more (which includes most hospitals and ambulatory surgery centers [ASCs] that perform even a moderate number of procedures), Veriscan will reduce scope repair costs by 31 percent, on average.”

The cost savings are due to increased detection of leaks, and also due to mandatory compliance with a best practices testing approach, he reports.

The EvoTech™ Endoscope Cleaner and Reprocessor (ECR), which also replaces manual endoscope cleaning with a built-in automated cleaning system, is another option for automatically detecting leaks. The ECR, offered by Advanced Sterilization Products, is designed to abolish the inconsistencies that can accompany manual leak testing and find leaks when they are still small.

“We designed the EvoTech to save time, enhance productivity, and to eliminate human variation in performing leak testing, which ultimately and consistently will result in a clean scope,” says Barbara Trattler, RN, NPA, CNOR, CNA, director for clinical education at Advanced Sterilization Products.

The EvoTech system performs leak testing before the cleaning and reprocessing of the scope. And, Trattler says, “It is designed in a way that is more natural for the positioning of the scope. It has a clamshell design, which facilitates the placement of the scope. Many of the scopes are very long and can be difficult to handle, so the system is designed with a helical tube that supports the distal end and tip during cleaning and high-level disinfection.”

The system performs the leak testing and then continues with blockage testing; its blockage and disconnect detection further ensure perfusion through all endoscope channels.

The purpose of integrating leak testing into the ECR is to eliminate the inconsistencies associated with the manual handling that exists today with manual leak testing. The system is designed to perform leak testing in such a way — based on the placement of the scope in the machine — that there is little coiling of the scope, Trattler explains.

“We do know that a small repair leak on an endoscope could be several hundred dollars, while a major leak has a much more significant financial impact — as expensive as thousands of dollars -- and then it is out of function for a significant period of time,” she adds. “This, too, affects the productivity and the efficiency of the GI suite.”

Mandatory Compliance

If a facility utilizes manual leak testing, there is no way for the department supervisor to ensure that a test has been performed. If scope cleaning and repair is done 30 times a day, then theoretically, 30 leak tests should be performed. However, there is no way to verify this.

If an automated process is used, it is easy for the nursing supervisor to access data from Veriscan to determine that although 30 scopes were used, only 24 leak tests were done, for example. Thus, she can ensure mandatory compliance by ensuring that the following day, all 30 leak tests are done.

“By detecting leaks far earlier and with greater accuracy than manual methods, we greatly reduce the risk of fluid invasion, which lowers damage and the risk of pathogens escaping disinfection (and creating a cross-patient infection hazard),” Bader adds.

Utilizing a digital means of leak testing can lead to a 98 percent detection accuracy, he continues. “That is 30 percent higher, on average, than manual leak testers.”

Manual Vs. Automated Testing

Traditional methods of leak testing are not infallible; even the most experienced reprocessors may miss leaks.

Both the traditional wet test and dry test have their own separate issues. With the dry test, although a very large leak will cause an obvious needle movement, small leaks may not. The device is analog, not digital, and detection of a leak may depend on a fraction of a second that a needle will move, or the small, nearly imperceptible movement of the needle that may be dismissed as “noise,” rather than indication of a true leak.

With the wet test, if a technician blinks, he may miss the bubbles that indicate a leak. Then, too, if an enzymatic solution is not fully rinsed off the scope, it may create bubbles. If there is, in fact, a leak, it can be disguised among the bubbles from the detergent.

The automated service, in contrast, replaces the manual leak testing protocols with a menu-driven testing process. It also can capture detailed data for each leak test (i.e., scope serial number, date and time of test, name of the technician, etc.), which can be printed or downloaded for analysis, which satisfies the growing regulatory demand for data documentation.

In the automated version provided by Veriscan, the technician attaches the machine to the scope, enters identification information, and presses “Start,” to run the leak test while he performs other tasks.

Soon afterward, a tone sounds, and the technician operates the scope’s angulation knobs and switches, then presses “Continue” to continue the test automatically. When the test has finished, a tone sounds, indicating whether the scope passed or failed the tests. Results can be printed, viewed on-screen, or downloaded. Then the next scope can be tested.

“The reprocessing room is a frenetic environment that can face an influx of 10 scopes an hour. The technician is faced with this rapid assembly-line environment and a series of multiple protocols — leak testing, manual cleaning, disinfection, drying, data documentation — many of which require multiple processing steps for compliance with best practices. This environment puts an unattainable burden on the technician,” Bader says.

Although the disinfection step of reprocessing has been automated with endoscope reprocessing machines, until recently, leak testing has remained manual instead of automated, Bader points out. The technician has the opportunity to stray from a proper testing protocol or to ignore it altogether.

Ignoring the leak test or missing leaks is common, he adds, noting that when the company performed pre-screening of endoscopes that were labeled “patient-ready,” 12 percent of them contained undetected leaks.

Another issue is with moisture entering the scope irrespective of a leak. The water-tight cleaning cap, for example, can be problematic, because the caps are sometimes left off entirely, poorly sealed, or even covered in fluid. (Some technicians will leave the cap sitting in a disinfectant fluid to prevent its becoming contaminated with pathogens.) When the wet cap is placed on the endoscope, moisture is allowed to enter the scope’s internal areas.

However, when the scope — which has just been wetted with a cleaning cap — undergoes manual leak testing, this fluid will not be detected if the scope is free of leaks. To address this issue, Bader says, the Veriscan tests for fluid, not just leaks.

Although there are compelling reasons to utilize an automated system for leak testing, many endoscopy departments swear by the old standby of manual leak testing, which remains the recommended means of testing for the SGNA and other gastroenterologyrelated societies.

Regardless of which method your department chooses, it is essential that leak testing be done, and done properly, not given short shrift. Proper leak testing can reduce your department’s repair costs by tens of thousands of dollars each year, and can protect the patients you work so hard to heal.

Leak Testing References

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