Lumened instruments come in all shapes and sizes — from the tiny ophthalmic cannulas to laparoscopic instruments to gastrointestinal endoscopes. they all have one thing in common: They're difficult to clean and can cause dangerous consequences if contaminated. Just turn to the recent deadly duodenoscope outbreak as an example (osmag.net/yD4PhV). It's a detailed practice, but lumened instruments can be reprocessed correctly if you follow the right steps and take advantage of technology aimed to make the job easier.
1. Pre-clean at the point of use
Many don't realize how important pre-cleaning at the point of use is. Keep instruments moist after use to ensure that blood, tissue and other body fluid doesn't dry and make the instrument harder to clean. After it's used, wipe the instrument down in the OR with a moistened towel or sponge to remove gross soil. After surgery, the lumen of the instrument should be flushed using a syringe and an enzymatic detergent, which helps start breaking down bioburden. Instruments with lumens should be flushed after use and either kept under a moist towel or soaked in a neutral pH enzyme detergent until they head down to central sterile processing.
To make this job even simpler, and keep instruments moist without having to fill a basin for soaking, new gel and foaming enzymatic detergents specifically designed for pre-cleaning can be applied quickly to instruments after they are used. These form protective barriers to keep instruments moist for longer. Special bags are also available that keep instruments moist after use and before cleaning can begin.
2. Soaking and manual cleaning
Even if you use an automated washer, manual scrubbing with a brush is one of the most crucial steps in cleaning lumened instruments. If residue is left inside the lumen, it will not be properly disinfected or sterilized.
After they arrive from the OR, a neutral pH enzyme detergent should be drawn into the lumen. The instrument can then be submerged horizontally in enzymatic detergent for a specified time listed in the manufacturer's instructions for use (IFU), typically 5 to 10 minutes. Make sure you have the proper concentration of detergent, as well as the correct temperature of the water. Automatic sink-filling systems aim to automate this process, reducing waste and ensuring instruments have a proper soak.
Next, instruments must be scrubbed using the correct brush. Information on the size and style of the brush is usually found in the manufacturer's IFU. The brush size should be the same diameter as the lumen — too small and it won't create enough friction to clean the inside of the lumen; too large and the bristles will bend or not fit correctly inside. Another option is pull-through channel brushes that are designed for hard-to-clean narrow channels.
Scrubbing should be done under water — the tech wants to minimize contact with the debris being pulled out of the lumen. Also note that brushes should be checked for wear and tear, which affects their ability to clean inside the lumen. Reusable brushes should be cleaned after each use and should be either disinfected or sterilized daily, according to the manufacturer's IFU. For endoscopes, techs follow a similar process except that a leak test should also be performed, following manufacturer's IFU.
WHEN CLEANING ISN'T ENOUGH
Sometimes, lumened instruments are just too difficult to clean, even if you follow the correct process. For example, AORN recommends the use of disposable ophthalmic instruments with cannulas when possible since the tiny lumens can be a risk. While I advocate minimizing waste, consider disposables for items like tiny plastic tubing that are too hard for busy techs to properly reprocess.
Another common problem I see is facilities that reprocess first-generation laparoscopic instruments, which don't come apart and are difficult to clean. I often see these instruments sent out for repair that, when taken apart, are caked with debris that's been missed for weeks or even months. If your docs are using these first-generation instruments, I strongly suggest considering new models that are designed to come apart for easy cleaning.
3. Flushing the lumen
Once scrubbing is complete, the lumen must be flushed with copious amounts of water to remove any remaining detergent and debris. For most instruments, you have the option of manual flushing using a syringe, or you can do mechanical high-pressure flushing using a variety of devices. While a syringe may be sufficient, I recommend finding a mechanical option since it's usually more effective.
New independent devices can flush lumens with high-pressure water and/or detergent with the added convenience of being hands-free. These devices feature a variety of connector attachments that allow a tech to attach the lumen to the device that pushes high-pressured fluid through it for a set amount of time to ensure it's clean. Another affordable option is water pistols, which work well for small facilities. These require a more hands-on approach from the tech since they need to depress the trigger to flush the lumen, but deliver a similar outcome.
For even more thorough cleaning, instruments can be placed into an ultrasonic washer following manual cleaning. While expensive, ultrasonic washers are able to remove fine debris that might be difficult to remove during manual cleaning. New ultrasonic cleaners feature channel adapters for lumened devices, allowing them to be flushed with detergent while removing any trace contaminants. Ensure the washer is drained, wiped down and refilled with fresh water at least daily or when the solution becomes cloudy or turbid-looking.
4. Cleaning verification
Cleaning verification is by far the most missed step in cleaning lumened instruments, yet it is the one that lets you know if the process is working. To check lumened instruments, you have several options. Some suggest simply running water through the lumen to check for any discoloration or debris, or using a moistened brush or pipe cleaner pulled through the channel. For a more detailed look inside the lumen, inspector scopes can be inserted to check for missed debris. Techs should perform a visual inspection of all lumened instruments after cleaning.
For a more precise look at your cleaning, lumen cleaning verification products should be used periodically to test for traces of missed protein. These tests feature indicators that are pulled through the lumen and test for the presence of residual soil (protein, for example). These tests come in different formats and are available for nearly all lumened instruments, including endoscopes.
If you're currently not performing these tests, start by first testing all of your lumened instruments after cleaning to get a baseline feel of your process. If you're consistently getting clean checks, then you can turn to societies such as the American Society for Quality (asq.org) for random sampling tables that determine how often these chemical verification checks should be performed, based on the number of instruments you process and use.
If you're consistently seeing problems after performing cleaning checks, it's time to analyze your process. Are you only performing manual cleaning and flushing? Then it may be time to invest in new automated technology. Is the instrument older and hard to clean? Look for updated models or implement a stricter policy for that device.
Following the recent duodenoscope outbreak, which left several patients dead due to problems with the cleaning of these tricky devices, some have been making the push for low-temperature sterilization for gastrointestinal scopes.
Low-temperature sterilization uses a variety of sterilants, including ethylene oxide or hydrogen peroxide, to kill nearly all microbes on the scopes. Sterilization provides a higher level of assurance that the microorganisms have been killed when compared to high-level disinfection. Many are now considering sterilization for notoriously hard-to-clean scopes such as duodenoscopes, with the hope it will prevent outbreaks.
It's important to note that low-temperature sterilization doesn't negate the need for manual cleaning — your staff will still need to pre-clean, scrub and flush the scopes. While, in theory, low-temperature sterilization could cut your risk of contamination, it can also create a false sense of security since sterilization, like high-level disinfection, is dependent on other steps in the process. If an instrument isn't properly cleaned then it might not be possible to disinfect or to sterilize the device.
Sterilization isn't foolproof, but it is seriously being considered as the next step in endoscope reprocessing. Currently, some societies are considering a change in their guidelines that would recommend that all gastrointestinal scopes be sterilized.
If you're considering adding low-temperature sterilization to your facility, consider several factors. No sterilant is considered better than another. While ethylene oxide is extremely effective, it requires a long exposure time and is a human carcinogen. Hydrogen peroxide is thought to be a more practical and popular option, yet it is very sensitive to humidity. Before purchasing, weigh the pros and cons of each unit in addition to looking at its compatibility with your devices, its size and the cost.
5. Disinfection and sterilization
What about the lumened instruments that can be steam-sterilized? After passing cleaning verification, package them with their tray, wrap or place them in rigid sterilization containers and place them into the autoclave. Some instruments require low temperature sterilization, so check with the manufacturer's IFU.
After testing, flexible endoscopes are ready for high-level disinfection or, in some cases, low-temperature sterilization (see "Is Low-Temp the Way of the Future?").
You can use an automated endoscope reprocessor (AER) to high-level disinfect scopes, or you can do so manually. If you have a decent volume of cases, consider an AER, which can really help standardize and improve your scope reprocessing. These machines perform a variety of tasks, including flushing channels and testing for leaks, making the process more efficient and effective. Still, it's important to note that as with all sterilization and high-level disinfection processes, you must first properly clean the instrument in order for the process to work.