
More healthcare–associated outbreaks have been linked to contaminated endoscopes than to any other medical device. Because of the types of body cavities they enter, flexible endoscopes acquire high levels of microbial contamination (bioburden) during each use. Today we are going to talk about appropriate cleaning and storage practices that will prevent the spread of healthcare–associated infections.
Association for the Advancement of Medical Instrumentation (AAMI) recommendations include removing clinical soil at the point of use as the first step in the cleaning process. Failure to promptly and properly initiate cleaning of endoscopes after use can increase the difficulty of cleaning and decrease the effectiveness of disinfection and/or sterilization. Immediately after use, scopes should be transported appropriately followed by meticulous manual cleaning in the endoscope processing area; all of which precedes the disinfection or sterilization process. Endoscopes should be visually inspected during all stages of handling and reprocessing – before, during, and after use, in addition to during and after cleaning and before high-level disinfection (HLD).
Prior to the disinfection process a leak test must be performed to validate the integrity of the scope. Heat sensitive endoscopes must be thoroughly cleaned using a high-level disinfectant after every use. The manufacturer can recommend what type of disinfectant to use for a specific device and make sure the disinfectants are compatible with the device. The Food and Drug Administration (FDA) also provides a list of approved chemical sterilants and high-level disinfectants that can be used for reprocessing. If the germicide is FDA-cleared, then it is safe when used according to label directions. Disinfectants that are not FDA-cleared and should not be used for reprocessing endoscopes include iodophors, chlorine solutions, alcohols, quaternary ammonium compounds, and phenolics.
The two products most commonly used for reprocessing endoscopes in the United States are glutaraldehyde and an automated, liquid chemical sterilization process that uses peracetic acid. The American Society for Gastrointestinal Endoscopy (ASGE) recommends glutaraldehyde solutions that do not contain surfactants because the soapy residues of surfactants are difficult to remove during rinsing.
Speaking of rinsing, thoroughly rinse the endoscope and all removable parts with clean water to remove residual debris and detergent. Purge water from all channels using forced air. Dry the exterior of the endoscope with a soft, lint-free cloth to prevent dilution of the HLD used in subsequent steps.
The device is now ready for disinfection/sterilization. There are a variety of methods available for disinfecting and sterilizing flexible endoscopes. To determine the method for a specific device, refer to the medical device manufacturer’s written instructions for use (IFU) and the intended use of the device. Validate that the method is cleared by the FDA for use in health care facilities.
To summarize, the cleaning process should be as follows:
- point of use treatment to remove external bioburden
- transporting the endoscope from the point of use to the processing area as soon as possible
- leak testing
- manual and/or FDA-cleared automated cleaning
- thorough rinsing
- exterior drying and channel purge
- inspection and testing for cleanliness
- disinfection/sterilization per manufacturer recommendations
The devices are now ready for storage. Newly disinfected and thoroughly dried endoscopes should be stored in an area that is clean, well ventilated and dust free as to prevent potential contamination. Endoscopes should be stored vertically or horizontally in a cabinet designed for scope storage and in accordance with manufacturers IFU’s. When sterilized endoscopes are stored vertically, the insertion tube should be as straight as possible, with the distal tip hanging freely. Scopes should not be touching each other.
Scope management is complex. Accrediting bodies will typically survey to compliance compared to what the manufacturers IFU’s demonstrate. This article only addresses cleaning and storage processes and does not demonstrate full compliance with AAMI/ANSI requirements for quality control, documentation, record keeping, and stock rotation, just to list a few of the required tasks.
References
ANSI/AAMI ST91:2021 Flexible and Semi-rigid Endoscope Processing in Healthcare Facilities
Centers for Disease Control (Updates, 2017), Disinfection of Healthcare Equipment
Multisociety Guideline on Reprocessing Flexible GI Endoscopes and Accessories (2020), approved by the American Society of Gastrointestinal Enterology (ASGE)
Society of Gastroenterology Nurses and Associates (2018), Standards of Infection Prevention in Reprocessing Flexible Gastrointestinal Endoscopes