Lumens, Channels and Suctions: Inspection 101

Surgical instruments and medical devices are evolving rapidly in our healthcare industry. The complexities that we see in flexible endoscopes, channels, suctions, laparoscopic lumens, and robotic instrumentation creates difficulty in properly processing these and increases chances for leftover debris, and possible damage. These complexities also make it very difficult for sterile processing professionals to utilize only their eyes for inspection. Relying strictly on the human eye for inspection can be dangerous and we should be investing in the use of a variety of tools and creative ways to advance our inspection practices. Building a very robust, inspection area in our preparations before sterilization can make or break the outcomes of sterility for almost any instrument.

Visual inspection of lumens can be assisted using a device called a borescope. A borescope is used for the internal visual inspection of surgical devices, or lumens and any other area that may be inaccessible by other means. Some borescopes are equipped with cameras that provide still images or videos of areas within the lumen or port. A small flexible fiber optic component can be pushed down into the lumen, to enable visibility that would otherwise be impossible. One of the most important considerations when using a borescope, however, is selecting the correct size in both length and width of the fiber optic component so sterile processing (SP) technicians have options for the instrument inventory they are inspecting. We know not all diameters are the same in our scopes, suction and laparoscopic channels, so having the ability to customize your borescope is key. Using too short of a fiber optic tip doesn't allow the entire length of the inner walls to be inspected just like when selecting a cleaning channel brush, the size makes all the difference.

Borescopes can be helpful during inspection because they can help technicians and SP staff members assess cleanliness or possible damage in difficult areas, such as the elevator of a duodenoscope or even inside of a shaver. A borescope can be a vital patient safety tool helping our frontline staff identify loose parts, bioburden or damage before using the device on a patient. In ANSI/AAMI ST91:2021 the term borescope populates 40 times and borescopic 3 times. When this document was released, it provided even more guidance on the proper use and importance of these tools. It’s important to understand that not all channels, on all scope models, can be seen using a borescope.

There are many different types of tools and equipment on the market today to aid the inspection process of channels and lumens. Let’s look at some best practices and things to incorporate in your department’s inspection station and cleaning sinks.

1. Cleaning Verification

After the cleaning process is completed it’s important to consider the verification of the items that were just cleaned often using a rigorous, time-consuming process. Each healthcare facility should have a multi-disciplinary team to determine the number of scopes or instruments to test, and the frequency of testing. This team should also establish benchmarks based on practices, and inventory quantities of each instrument. There are several available technologies that can be used to measure the levels of organic soil. The most commonly used tests include;

i. Adenosine triphosphate (ATP)
ii. Protein Swab testing
iii. Hemoglobin testing
iv. Water lumen flush test

All testing should be carefully, and completely documented, and failed test results must be investigated. These tests are performed before any disinfection or sterilization process begins and are used to verify the effectiveness of the cleaning process. It is not recommended to perform a cleaning monitor test after any cycle run in an AER.
High-risk endoscopes, or scopes with complex design, should also be considered and have a dedicated process for inspection and cleaning verification. These scopes include ureteroscopes, endobronchial scopes, and duodenoscopes. Duodenoscopes have been linked to complications with cleaning because of their elevator mechanism. The FDA has made many recommendations to the use of advanced technology when processed or utilizing these scopes on patients.
Adding any flushing agent to an instrument, post cleaning, should only be performed when approved and indicated by that device manufacturer. For example, using 70% to 90% ethyl or isopropyl alcohol as a preliminary flush, can aide in the drying process. If this process is in place for flexible scopes, a multi-disciplinary team should conduct a risk assessment to determine whether the scopes lumen should be flushed. This should not however, be the routine practice for all instrument channels because of alcohol’s fixative properties.
Flushing water through lumened instruments is a practice being implemented at preparation. Sterile water can be flushed down a lumen, to determine if there is any discoloration or lodged debris inside the channel. This process is often used for smaller items like baron suctions, when borescope channels might not fit, or the use of a lumen push/pull suction doesn’t work. Make sure to dispose of the water frequently, use disposable and correct sized syringes, and dispose of all surface lining used to catch the water when flushed. If any contamination does occur, the preparation station will need to be cleaned and disinfected before moving on. This process opens the possibility for cross contamination.

2. Lighting

Adequate lighting in employee work areas should be provided to aide in the inspection and cleaning processes. Without proper visibility and lighting it can be quite difficult to verify cleanliness and proper functionality while inspecting. ANSI/AAMI ST91:2021 gives guidance on proper illumination for each process workspace area, in 4.3.2 Table 1. There are three levels of lighting for each category and this guidance can be very useful when setting up your workstations. Lighted magnification is another piece of equipment that should be available to help with the inspection process, and can help with accessories, and items like flexible scopes, laparoscopic instruments and suctions.

3. Drying

Research has proven there are a variety of methods for drying scopes and channels. Forcing highly filtered air or instrument air through channels facilitates drying and is a very affordable option. One consideration with forced air is the pressure being applied to the channel, and the potential for damage of interior components. Manufacturer instructions for use (IFU) must always be followed to determine the appropriate air pressure (PSI). Drying cabinets are now available with many options, including channel drying components that allow for customized cycles, temperatures, air flow, pressure and attachment hook ups. These cabinets are often designed with options for lumens, and channel drying.

Research has not yet established an acceptance criterion for adequate dryness, so verification of drying is challenging to accomplish due to that limitation. A borescope might be helpful to also visualize residual moisture, post drying phase. Often, scopes will be hung in a cabinet with a dedicated drying time established by your facility. While this practice does aide in the drying process, there is still no dryness guarantee. For lumens in other instruments such as suctions, robotic arms, and laparoscopic instruments, forced instrument air is usually an approved process, based on the IFU.

Visual inspection is such an important part of the quality process and failure to detect damage or residual soil, following cleaning, is a patient safety issue. It is important that inspection takes place in a well-lit area, and each station is equipped with the proper tools and equipment. Adequate lighting is the first step in developing a good visual inspection process. Remember that inspection includes assessing cleanliness, looking for missing parts, clarity of view, integrity of the components and appearance of physical or chemical damage.

Resources

Flexible and semi-rigid endoscope processing in healthcare facilities, ANSI/AAMI, ST:91:2021, Arlington VA, 2022.

Endoscope Reprocessing Manual, second edition, healthcare sterile processing association, Chicago, IL, 2022.