Processing endoscopes: 6 areas of competency for proper care and handling

by Donna Ungvarsky, M.S.N., M.Ed., R.N., CNOR, and Eileen Young, R.N., CNOR

Endoscopes are complex medical device instruments used to examine the human body. They are inserted through small incisions into natural cavities, such as joints and the abdomen and through every natural orifice in the human body.

While there are a variety of endoscopes, all of them have some common features: They are facility investments to acquire and repair, they are fragile and require special handling to reprocess effectively. The key is to protect your investment and reduce the repairs through proper care and handling including reprocessing.

Many endoscope repairs are related to improper or incomplete reprocessing. Policies and procedures must be implemented and employees held accountable for complying with the process.1-4 The entire process begins with adequate training. Personnel must be trained on the device as well as the process. Competencies should be developed and reviewed at least annually, but perhaps more frequently with new staff.¹ In addition, the reprocessing staff needs to have sufficient time to complete all of the steps in the process.¹ Expediting the reprocessing procedure inevitably results in skipping critical steps that can contribute to damage and inadequate cleaning, resulting in damage to the device and transmission of microorganisms.

The six common areas for concern in the reprocessing procedure are pre-cleaning, leak testing flexible endoscopes, manual cleaning, high-level disinfection or sterilization and storage.

Pre-cleaning

Pre-cleaning at the point of use is critical to initiate the cleaning process, reduce visible bioburden and facilitate thorough cleaning once the endoscope arrives in the central processing area.^1-5 Effective pre-cleaning is dependent on proper disassembly of components and seals. Pre-cleaning should be performed with clean water or an enzymatic product. Saline should never be used to clean any instruments as it can lead to corrosion, pitting and will leave salt residues. Many flexible endoscopes require a cap and/or adapters to facilitate the pre-cleaning process and prevent fluid invasion.^4,5

Leak testing

Most flexible endoscopes must be leak tested prior to manual cleaning.^2-5 The leak tester introduces air into the endoscope to reveal any tears or perforations that would allow the cleaning solution to penetrate the inside of the endoscope and result in significant damage from fluid invasion. The manufacturer’s instructions should be followed when using the leak tester, but most commonly, the pressure is held for 30 seconds.

It is important to use a basin or sink that is large enough to be able to visualize any bubbles. The minimum recommended basin size is 16 inches by 16 inches. Immerse the entire endoscope for leakage testing, not just the insertion tube or distal tip, because leaks can occur anywhere along the endoscope. The endoscope may be placed in clear water after the pressure is applied. Clean water should be used for each endoscope, and soap should never be added during the leak test. Observe for leaks during complete immersion of the endoscope while manipulating angulation controls and switches. A steady stream of bubbles and/or a loss of pressure are two indicators of a leak. Following a successful leak test (no leak observed), the air should be depressurized at least 10 seconds.

If a leak is detected, the endoscope can be manually cleaned and disinfected, with the leak tester attached and the pressure maintained. If the endoscope is compatible with ethylene oxide gas or hydrogen peroxide plasma, it is generally permissible to use for sterilization. The manufacturer should always be consulted if there is any question about the proper process to decontaminate a damaged endoscope.

Some small diameter endoscopes may not require immersion for leak testing. In those cases, the gauge on the leak tester must be observed to confirm the pressure is maintained for the 30 seconds. If a leak is detected, the endoscope must be cleaned and decontaminated with the pressure maintained throughout the process to avoid additional fluid invasion, as described above.⁵

Leak testers can become damaged through normal use and must be checked according to the manufacturer’s instructions to ensure they are functioning properly. A leak tester can actually push moisture from a wet connector cap into the endoscope causing fluid invasion; therefore, be sure to check the inside of the cap prior to attachment to the endoscope for moisture.

Manual cleaning

Manual cleaning is the next step in reprocessing. The actual site where manual cleaning is performed may be located in many different areas depending on the facility and the availability of space. An area that is dedicated to reprocessing with trained personnel and all necessary supplies will facilitate cleaning following the established, standardized procedure. It is required to follow the same procedure each and every time the endoscope is reprocessed.^2-5

The manufacturer should supply validated cleaning steps to assist in developing appropriate procedures. The detergent or enzymatic product should be cleared for surgical or endoscopic instruments and must be diluted to the recommended strength with the correct temperature water. Products should never be mixed unless they were designed to be used in combination with each other. Endoscopes should be fully immersed in the cleaning solution.^1,2,4 If there is a recommended soaking time, a timer should be used to confirm exposure time. Enzymatic detergents may need several minutes to effectively remove the bioburden. Channels need to be cleaned either with an appropriate size brush in good condition, and/or flushed with the cleaning solution. The manufacturer’s instructions should provide information on the type and size of brush and/or the volume of fluid to flush the channel.

Unless specifically instructed by the endoscope manufacturer, ultrasonic washers should never be used on optical devices such as endoscopes and telescopes as vibrations can damage lens seals and fracture optical fibers. Always check the instructions for use to determine if an ultrasonic cycle is compatible with accessory devices or rigid sheaths.

Significant damage can result from inadequate or delayed cleaning. Prompt manual cleaning is important to prevent the bioburden from drying or the formation of a biofilm. Biofilm is an accumulation of bioburden and extracellular material on a surface and is extremely difficult to remove using standard cleaning methods.³ Once bioburden dries on a surface, or inside the channel, it can be almost impossible to clean. And, if it can’t be cleaned, it can’t be high-level disinfected or sterilized. Additionally, the residual bioburden can inhibit introduction of accessories and manipulation of the flexible tip of an endoscope.^2-5

Although it is difficult to monitor the effectiveness of cleaning, there are some products that are commercially available to validate the process by checking the level of adenosine triphosphate (ATP) before and after the cleaning process to indicate a reduction in contamination. There is some controversy over the use of this practice, but it can be used to measure competencies and randomly check the effectiveness of the procedure.⁶ This practice has not been incorporated into any of the published guidelines at the time this article was written.

High-level disinfection

Devices are classified using the Spaulding classification system to determine the level of decontamination required. The Spaulding classification system is based on the potential of the device to transmit infection. Generally, if the device is entering a sterile cavity, it represents a strong possibility of transmitting infection and the device should be sterile. This would include laparoscopes, arthroscopes and ureteroscopes.

Devices that enter cavities that are not normally sterile and have an intact mucous membrane are considered semi-critical devices as the mucous membrane serves as a barrier for spore-forming bacteria that might not be inactivated by high-level disinfection. Semi-critical endoscopes include gastrointestinal endoscopes, bronchoscopes, laryngoscopes, and in some cases cystoscopes.^2-3

Many GI endoscopes are reprocessed by high-level disinfection in an automated endoscope reprocessor (AER), although they may still be reprocessed manually. The advantages of an automated system include the standardization of the process and removal of the microbial bioburden. Some AERs include a cleaning process, but many require some level of manual cleaning prior to putting the endoscope into the system. AERs must be used according to the instructions provided by the manufacturer of the reprocessor and compatible with the endoscope.^3-5 Always check that the instruction manual you are referencing is for the correct model and is up to date. The manufacturer may have updated manuals available on their website.

Only a few chemicals are approved for high-level disinfection, although these chemicals may be marketed under different trade names. Glutaraldehyde, ortho-phthalaldehyde, peracetic acid and hydrogen peroxide are the most common high-level disinfectants used on medical devices. Each of these chemicals must be used according to the manufacturer’s written instructions and must be compatible with the materials of the endoscope.³ Most endoscope manufacturers test for efficacy and material compatibility with some chemicals, but may not necessarily test all chemicals. The steps used by the manufacturer to validate the efficacy must be followed by the facility to ensure safe and effective reprocessing. If the steps cannot be duplicated at the facility, the result may be an inadequately processed device. These steps are contained in the instructions for use manual supplied with the endoscope.

All chemicals used for high-level disinfection must be tested prior to each use to confirm that the concentration is sufficient to result in a properly disinfected device providing adequate exposure at the recommended temperature. This test is referred to as the Minimum Effective Concentration (MEC) level and should be documented in a log. A sample documentation log is shown in Figure 1. The date the chemical was opened should be recorded. The length of time a chemical can be stored and used once opened is variable and it is important to follow the directions on the label.^2,4,7

If an AER is used for reprocessing, the correct adapters must be attached to the channels of the endoscope. These adapters are supplied by the manufacturer of the AER and may be specific to the make and model of the endoscope. The reprocessor must be used as the manufacturer designed it, and all testing and maintenance protocols must be followed to ensure the reprocessor is performing properly.4 If a cycle is interrupted for any reason, it must be repeated to ensure adequate decontamination and processing.

Sterilization

Small diameter flexible endoscopes, rigid and semi-rigid endoscopes are often sterilized rather than high-level disinfected. These endoscopes are commonly used in an operating room where there may be more options for sterilization. Many rigid telescopes and sheaths are compatible with steam sterilization, but always confirm sterilization compatibility with the manufacturer of the device.^1-5 The reliability of sterilization depends on the number, type and inherent resistance of the microorganisms on the items to be sterilized, as well as surrounding oils, soil and other materials that may shield or combine with and inactivate the sterilant.³ The importance of removing debris and bioburden on the device to be cleaned cannot be over emphasized.

Storage

The final step in reprocessing is related to storage. Once the endoscope is cleaned and high-level disinfected, the endoscope is ready to be stored until needed for use. Endoscopes should be hung so that the control section of the endoscope is supported, with the deflection in neutral and the shaft hanging straight down and not touching anything. This allows any residual moisture to drain. A ventilated cabinet is the ideal storage space to protect the endoscope. All removable parts should be removed for storage as fluid can be trapped and provide an environment conducive to proliferation of microorganisms.^2-4 The AORN Recommended Practices (RP)⁵ for flexible endoscopes recommend that a properly decontaminated gastrointestinal endoscope that is stored according to the RP can be used up to 5 days following terminal disinfection. This recommendation is not supported in either the SGNA Standards4 or the Multisociety Guidelines.²

If an endoscope is sterilized, it can be stored in the sterilization container or wrapped tray. The container or tray must be stored in an area where the humidity is controlled and where it is protected from contamination. Devices that are sterilized in the Steris System 1E, are intended to be used immediately after the sterilization cycle is completed. There is no mechanism to maintain sterility for use at a later date or time.

Rigid, rod lens telescopes can be a challenge to store. They require protection from other devices that can cause damage from impact and result in dents, chips and scratches. Telescopes should be stored separately from other surgical items. If they are placed in a tray of instruments, it is important to protect them as much as possible. Some small diameter telescopes (usually 5 mm or smaller), may have storage/sterilization tubes that can be used. Check with the manufacturer to determine if the tube was validated to be sterilized while on the telescope. Ensure that other devices are not stacked on any rigid endoscopic device. The thin walls of sheaths and bridges can be dented and restrict the smooth assembly and passage of any devices through the channels. Trays need to be thoroughly dried following steam sterilization to avoid damp packs and potential corrosion of the devices inside the tray.

Training rules

Endoscopes enable minimally invasive access to many areas of the human body and can be a source for the transfer of microorganisms if they are not properly cleaned, disinfected or sterilized and stored. Because of this, adherence to recommended practices and guidelines for reprocessing is a critical component of infection control and reducing the risk of nosocomial infections. While the device manufacturer is the best source of information on reprocessing a specific device, facility personnel must be appropriately trained on infection prevention and proper handling and reprocessing procedures to ensure safe and effective procedures.

Donna Ungvarsky, M.S.N., M.Ed., R.N., CNOR, is Clinical Nurse Educator, and Eileen Young, R.N., CNOR, is Manager, Clinical Nurse Education, at Olympus America Inc., Medical Systems Group.