This site is part of the Global Exhibitions Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 3099067.


ChannelCheck Verification Test as a Tool to Assess Endoscope Cleanliness


By Natalie N. Whitfield, PhD

Objective: The purpose of this study was to determine the real-world effectiveness of healthcare facilities’ flexible endoscope cleaning procedures by utilizing the ChannelCheck™ residual soil test, a product of Healthmark Industries Co, Inc. The ChannelCheck™ test detects the presence of organic contaminants and can serve as a quality control tool to identify potential deficiencies in endoscope reprocessing effectiveness, typically failure results from not following reprocessing standards and guidelines or the use of damaged or defective equipment.

Study Design: A total of 12 healthcare facilities were recruited to participate in this study. At each facility, the instrument/suction channel of 10 endoscopes was tested using the ChannelCheck™ product before and after cleaning, but prior to high-level disinfection. The ChannelCheck™ product tests the presence of three organic contaminants, including carbohydrate, hemoglobin and protein. Following ChannelCheck™ testing at each facility, participants completed a survey identifying the reprocessing methods used at the facility.

Results: Of the 120 endoscopes tested, cleaning removed the majority of the residues detected prior to manual cleaning of the endoscopes. The most common residue found before manual cleaning was hemoglobin, (54 percent or 65 endoscopes); however after the cleaning procedure only 4 percent (five endoscopes) of these endoscopes yielded a positive result for hemoglobin. The endoscopes that were positive for organic residue post-cleaning were positive for one or two residues; however, one gastroscope was positive for all three soils, both before and after the cleaning process.

Conclusion: The ChannelCheck™ is an easy to use and effective tool for monitoring the endoscope cleaning process and demonstrating competency of facility reprocessing staff.

Background. In the United States, there are an estimated 34 million gastrointestinal (GI) endoscopy procedures performed annually (Lieberman, De Garmo, Fleischer, Eisen, & Helfand, 2000) (Owings and Kozak, 1998) (Seeff, et al., 2004). Although the estimated risk of transmission of infection during endoscopy is extremely low (Nelson and Muscarella, 2006), flexible endoscopes are still an important concern. Most infections have been linked to errors occurring during reprocessing events, in particular cleaning procedures (Nelson, et al., 2003). More recently, several headlines have highlighted the importance of decreasing the potential risk of cross-contamination from endoscopy procedures.

Because patient safety is of critical concern when reprocessing endoscopes, several guidelines and standards have been established to ensure that proper reprocessing is performed (SGNA, ASGE, APIC, AORN and ASTM) (SGNA, 2009) (Nelson, et al., 2003). However, without proper training and failure to adhere to the established guidelines there is an increased risk of survival of microorganisms and infection (Alfa, 2006). In addition, failure to properly clean an endoscope can potentially inhibit the subsequent disinfection and sterilization processes:

"Thorough cleaning are the first and most important steps in the reprocessing of any reusable medical device. Without thorough cleaning… it is not possible to achieve high-level disinfection or sterilization of the device. The purpose of cleaning and rinsing is to remove all adherent visible soil..." (AAMI TIR12, 2004)

"Of particular significance is the need to thoroughly manually clean equipment prior to any manual or automated disinfection or sterilization process." (Endoscopy Working Group, 2000)

"…two colonoscopy patients were infected with hepatitis C…The investigation concluded that the biopsy channel had not been properly cleaned and the disinfection failed." (Bronowicki, et al., 1997)

The adherent soils that may result from microorganisms, patient material or both, if not removed may potentially induce pyrogenic and anti-genic reactions in a patient. Residual organic material following cleaning may also become attached to the device surfaces as a result of the sterilization or disinfection process. The most widely used chemistries for high-level disinfection are aldehyde-based chemistries, which fix organic material on the surface. This fixed material may offer protection for underlying microorganisms from exposure to the disinfectant or sterilant (ANSI/AAMI ST79, 2009).

Endoscope design presents an inherent cleaning challenge due to the long, narrow lumens that are an integral part of their structure and function. Consequently, methods that allow reprocessing personnel to monitor their cleaning procedures are a necessary addition to their practice, which reduces risks associated with inadequate reprocessing of these devices. Several documented sources support the need for such methods to monitor the cleaning process:

"Because disinfection and sterilization cannot be assured unless the cleaning process is successful, professionals in the field ought to seek out whatever means are available and practical to verify this function" (ANSI/AAMI ST79, 2009)

"Cleaning verification by users should include (a) visual inspection combined with other verification methods that allow the assessment of both external surfaces and inner housing and channels of medical devices." (ANSI/AAMI ST79, 2009)

Currently, few products exist for this purpose. A successful verification test for acceptable endoscope cleaning must take into consideration the design of the endoscopes, be feasible for routine use, and be cost effective and easy to interpret. The objective of this study was to determine the usefulness of the ChannelCheck™ test strip to monitor the success of endoscope cleaning procedures.

Round-Robin Study Method. Healthcare centers (hospitals, ambulatory care centers, and endoscopy clinics) across the U.S. that showed interest in participating, were recruited to assess the use of the ChannelCheck™ as a method to determine whether proper cleaning of patient-used endoscopes was accomplished. Participants likely have an increased interest in proper reprocessing, demonstrated by their willingness and choice to participate in this study. Participants from the healthcare centers tested the instrument channel of 10 endoscopes twice; first, after bedside cleaning following the patient procedure, and second, immediately after manual cleaning, but prior to high-level disinfection or sterilization. The endoscopes were tested by flushing the instrument/suction channel with sterile deionized water and immersing the test strip in the flush fluid for 10 seconds. The ChannelCheck™ test strips, used for verification testing, detect the presence of protein, carbohydrates, and hemoglobin in approximately 90 seconds. A color change on any of the three pads indicates a positive result requiring that the endoscope be re-cleaned due to the presence of organic residues from patient or microorganism contamination. Participants were also supplied with a log sheet to record all results. Upon completion of their testing, participants were asked to return log sheets and respond to a survey regarding details of their reprocessing procedures.

« Previous12Next »
comments powered by Disqus