Handle With Care
Cleaning and Disinfecting Rigid and Flexible Scopes
By John Roark
Scopes are delicate instruments that must be handled with care but cleaned and disinfected with vigilance.
The infection risks associated with both flexible and rigid scopes is a serious issue. Proper cleaning, disinfection and sterilization of these instruments must be continually monitored and consistently maintained. Association of periOperative Registered Nurses (AORN) recommended practices effective Jan. 1, 2003 state:
Rigid and flexible scopes have different cleaning and sterilization needs and can pose different threats when it comes to infection control.
The rigid scopes are much easier to clean, but pose a greater risk, says Lawrence Muscarella, PhD, chief of infection control at Custom Ultrasonics, Inc. The flexible scopes are harder to clean, but pose a lower risk.
It is important to bear in mind that scopes are made up of many different components, each requiring special attention. Each valve, channel and surface of the endoscope in and of itself is a unique medical instrument, says Muscarella. An endoscope is arguably comprised of seven or eight separate sub-instruments. Each of those instruments needs to be addressed during reprocessing. Once you understand that its a multi-instrument, you know that theres a different set of rules that would apply than if it were a scalpel, which you would consider one instrument.
Whenever a scope is processed, all channels must be cleaned, even if they werent used during the procedure.
Problems can occur when someone is not educated, says Muscarella. You cant train your personnel how to clean the easiest endoscope and expect them to do the job flawlessly. You need to train that person on the most complex type of instrument to reprocess, which is probably the GI colonoscope or GI side-viewing duodenoscope. There has to be attention to every single channel of the endoscope, whether that channel was or was not used during the procedure. If you have knowledge of all of the endoscopes and you understand that different models have different designs and therefore different needs, the steps will be the same, but the adaptations may be different. Youre going to have a problem if you dont adapt properly.
A basic framework can be followed to help ensure that scopes are receiving optimal care. Each step is as important as the others, and no step should be compromised.
Step One: Pre-Cleaning
The first essential step in the cleaning process for both flexible and rigid scopes is pre-cleaning wiping down the scope and immersing it in enzymatic detergent mixed with water immediately after the procedure to remove any bioburden or debris. Only a detergent that has been shown by its manufacturer to be effective should be used during endoscope reprocessing. Do not use a detergent for which data are not available.
Some common mistakes made at this critical juncture, says Lee Ann Purtell, product manager of rigid scope repair for Mobile Instrument Service & Repair Inc., is that often, scopes are soaked for too long.
The general rule of thumb is that no scope should remain immersed in any solution even distilled water for more than 60 minutes. Follow the manufacturers recommended soaking time. When it comes to enzymatic cleaners, people will think more is better. Theyll put more enzymatic detergent than is necessary in the mix of water. High concentrations of detergents can leave surfactants on the glass, which are very hard to remove. They can discolor parts of the scope, and can pit the glass. Dont use too high of a mix, and dont soak too long.
A lot of times, scopes will sit in a bin of glutaraldehyde, says Rob Purtell, product manager, also with Mobile Instrument Service & Repair, Inc. Its very important not to leave them in longer than the published time. If a scope is supposed to be in a cold soak for 20 minutes and you forget about it and leave it in there for several hours, it can begin to eat away at some of the components. Ive seen scopes that have been left overnight. It will do a tremendous amount of damage follow the published soaking guidelines from the manufacturers that make that fluid.
Flexible scopes have an appearance that belies their fragility, continues Rob. A lot of times nurses or techs will have the scopes coiled up almost in knots. The scope naturally flows a certain way if you begin to coil it up into a sink full of water. There are some weaker points on the tubes that can be damaged if looped improperly.
Lee Ann also cautions against soaking scopes beneath other instruments. Its best to keep them separate, and you never want to put anything heavy on top of the scopes.
Step Two: Leak Testing
An essential step for flexible scopes is the leak test, designed to gauge the integrity of the scope, and that no fluids have leaked into the internal channels. You need to make sure that the scope is holding air when you put it through the cleaning process, says Rob. If a scope has a breach that will allow fluid to get inside, it can cause damage to the internal components. Once the fluid gets in, theres no way for it to get out repair companies have to open up the entire scope and put it in an oven to dry it out. Inside the scope there are stainless steel components that will rust, there are also video components and wires that can get corroded.
Muscarella cites a report of a damaged bronchoscope infecting a patient. The hospital failed to perform the leak test, and as a result, they were transmitting disease from patient to patient, he says. Had they done the leak test, they would have determined that there was damage to the instrument. It isnt just fluid invasion that you get you can get microbial invasion into any kind of a tear, pit or laceration on the internal channel. You cant see down the internal channel you have no way of knowing if it was damaged. Leak testing is important not just for the functioning of the endoscope, but for raising a flag that your instrument may be a potential carrier of a disease.
Step Three: Manual Cleaning
Manually brush all channels that can be brushed, says Muscarella. What you cant brush, flush with enzymatic detergent (or other detergent for which efficacy data are available), and soak according to the detergents labeling paying strict attention to recommended time, dilution and temperature. Some of these detergents can cause problems to the scope or the automated reprocessor, he says. You dont want to immerse the endoscope in the detergent or the disinfectant for longer than recommended. The concept of, if the label says 15 minutes, 30 minutes is twice as good, does not apply.
Rigid scopes should be carefully cleaned by hand with a soft cloth, using care and caution. Lenses can be scratched by an abrasive agent. Rigid scopes should only be put through instrument washers or used in any ultrasonic device labeled to be compatible with rigid endoscopes.
Step Four: Rinsing to Remove Detergent and Soil
Lee Ann recommends rinsing scopes two or three times with distilled water to remove all residual cleaning solutions. That is a common mistake, she says. People dont rinse them, and the cleaning solutions can build up on the lenses. They look hazy or fuzzy, and you cant see through them. Use an alcohol wipe to gently remove the surfactants, or gently use a pencil eraser to erase the film. If it doesnt come off, its probably pitted the glass, and it will have to be repaired.
We also suggest at this point prior to sterilization that the scope be inspected to make sure that all parts are intact, that theres no damage to any of the components, continues Lee Ann. Use a jewelers magnifying glass to look at the lenses to make sure they are not damaged, chipped or scratched. Using a scope that has potential damage can weaken the parts, which can fall out into the patient. Its important not to be putting something back into service that is damaged.
The cleaning step becomes a real saving grace if the disinfectant is approaching its minimum effective concentration, or if some shortcut is taken in the disinfection step, says Muscarella. It reduces the bioburden considerably, so when you go to the next step of disinfecting, you have much less of a challenge, much less of a formidable problem on your hands.
Step Five: Disinfecting/Sterilizing
Sterilizing [rigid scopes] is tricky because there really is no perfect option currently out there, says Lee Ann. Every method available has its benefits and limitations. ETO gas is probably the least damaging to the scope, and it will sterilize the instrument. However, people dont use it because the turnaround time is prohibitive.
Both Sterad and STERIS are quick, readily available chemical methods of sterilization. With chemical sterilants you can get discoloration, it can remove any kind of coatings from anodized parts, and depending on the grade of glass thats used by the manufacturer, you can get some pitting, says Lee Ann, who points out that STERIS is for point-of-use processing only. You can STERIS the scopes between cases, but you cannot STERIS at the end of the day, put it on the shelf, and then use it the next day.
Steam sterilization and autoclaving present inexpensive solutions for newer rigid scopes specifically labeled as autoclavable. Older scopes will be damaged by the heat employed in these processes.
Lee Ann also cautions that immersing hot instruments in cool water after sterilization will cause thermal shock, and will fracture the components. For flexible scopes, Muscarella reiterates the importance of monitoring the temperature, time and concentration of disinfectants.
Step Six: The Second Rinse
Rinsing flexible scopes after disinfecting is an important means of removing any residual disinfectant. If you dont get rid of the disinfectant that remains, it can cause patient injury, says Muscarella. The residues of that disinfectant or detergent can come in contact with the patient, and cause a reaction by the mucosa of the organ whether its the colon, the lungs or the esophagus youve got to get the disinfectant off to protect the patient.
Muscarella also comments on the rinse water controversy, and the importance of monitoring the quality of the rinse after disinfection. Arguably, the Achilles heel of the entire endoscope reprocessing protocol is the quality of the rinse water, because its the last thing thats going to contact that instrument before its placed in the patient, he says. If the water itself is contaminated with chemicals, it can cause a problem. And if its contaminated with bacteria, its obvious what it can do.
Ive taken the position that you cant allow any bacteria in the rinse water because endoscopes and bronchoscopes may sit between uses, and that bacteria will proliferate. To someone who is immunosuppressed, introducing just a few bacteria into the lungs can kill them.
Step Seven: Drying
Thorough drying will break the chain of bacterial transmission from possibly contaminated water. You will not get bacteria from the water to the patient via the endoscope if you dry it, says Muscarella. From a high-level disinfectant and liquid sterilization standpoint, its essential to do, because it stops the transmission of any bacteria in the water. If youre not monitoring the rinse water, its all the more important.
Step Eight: Storing
Flexible scopes must be stored in a low humidity, well-ventilated dry area. You can properly perform all of your cleaning and disinfection steps, but if you dont properly store the endoscope, you could run into a problem, says Muscarella. Lets say you have very, very few bacteria in your endoscope. If its stored in a wet environment, you now allow those bacteria to double every 20 minutes. In an eight-hour time period, you can go from an instrument that is completely patient-safe to one that is extremely hazardous for use simply because you didnt store it in a dry environment.
Humidity control is not as much of an issue with the rigid scopes, but moisture penetration, airborne contaminants and handling that would cause the package integrity or seals to be broken are factors to be aware of.
Lee Ann stresses the need for carefully handling and storing scopes, which are more fragile than they appear. The components inside are primarily glass, she says. Any kind of pressure on the insertion tube dropping it, laying something heavy on top, putting any kind of pressure on it can break the parts. All the people in central sterile, anyone who handles the scope really has to pay some special attention and handle them carefully.
The Bottom Line
Attention to detail, awareness of manufacturers guidelines and keeping an eye out for potential problems are the keys to safer scopes. I go to hospitals to train, and I find more and more that people are just not following the original guidelines by the manufacturer, says Rob. When they buy the scopes, the manufacturer comes in and does the training. The turnover in facilities can be tremendous new people come in and the information never gets trickled down the way it should. A lot of times customers will tell me that the manufacturer last came in six years ago thats the last time they had any formal training on it. The only consistency I ever see is that I almost always find something. Its rare to see a facility thats really doing things carefully and properly. Theres usually a breakdown in the process someplace.
First and foremost is education and training, says Muscarella. Make sure that reprocessing personnel have access to the internal schematics of every single endoscope they have in inventory, ideally with some kind of chart on the wall, so they can reference each of the models and see what makes up each scope. Periodic testing and monitoring by supervisors to make sure that all those scope models are understood is equally important. If the facility does not ensure its staff is well trained and properly performing each reprocessing step in accordance with published reprocessing guidelines, it is opening itself up to a lawsuit. Plain and simple.
Because GI endoscopy has a very low reported risk of infection, people get complacent, and corners are cut. The problem with endoscopes is that they are unlike most other types of instruments. Its one reusable instrument that is very complex, and may be used on more than a dozen patients during the course of a single day. If there is a undetected problem with any one of the reprocessing steps, there is an exponentially high number of patients who may have been infected with pathogens. This potential outcome underscores the importance of periodic training and routine monitoring of each the facilitys reprocessing steps to ensure staff is in compliance with published guidelines. Ideally you would like a disposable scenario, but you dont have it. Even though the risk appears to be low, peoples guards are down, and as a result they get a little sloppy. Youre playing with fire when youre involved in endoscope reprocessing.