Originally published by our sister publication Gastroenterology & Endoscopy News
An automated endoscope channel cleaner removed more biofilm from endoscope channels than manual channel cleaning in a simulated experimental protocol conducted by endoscope manufacturer Nanosonics.
Biofilms can remain in endoscope channels even after manual cleaning, presenting a risk for infection (Infect Control Hosp Epidemiol 2022;43[2]:174-180). Nanosonics tested whether a new automated cleaning approach might yield better results, and researchers reported results in the Journal of Hospital Infection (2024;150:91-95).
The investigators used polytetrafluoroethylene (PTFE) channels (the same ones used in flexible endoscopes) in two different sizes: a 3.7-mm inner diameter channel to represent an endoscope’s suction/biopsy channels and a 1.4-mm inner diameter channel to represent air/water and auxiliary channels. They created “cyclic build-up biofilm” inside the PTFE channels and then cleaned one group using current manual cleaning methods and the other with an investigational automated endoscope channel cleaner (AECC) that uses high velocity to push proprietary cleaning agents through the endoscope channels.
Compared with manual cleaning, the AECC removed more total organic carbon and proteins from the larger suction/biopsy channels and smaller air/water channels.
In the suction/biopsy channels, both cleaning methods removed sufficient protein (<3 mcg/cm2) and total organic carbon (<6 mcg/cm2) to meet a satisfactory level of cleanliness. However, use of the AECC resulted in removal of more colony-forming units of microorganisms (=106 CFU/cm2 reduction) in the suction/biopsy channels compared with manual cleaning (<102 CFU/cm2 reduction; P<0.001). In addition, the AECC achieved biofilm removal in all air/water channels (P<0.001).
The AECC’s velocity is higher than that used in standard manual cleaning, and the cleaning agent provides excellent friction in all channel diameters, said Michelle Alfa, PhD, MSc, a certified clinical microbiologist (retired) and the CEO of AlfaMed Consulting, in Winnipeg, Manitoba, who advised the Nanosonics researchers. Dr. Alfa wrote an editorial in 2025 on novel technology for automated endoscope cleaning and argued that compliance with manufacturers’ instructions for use needs improvement (Endosc Int Open 2025;13:a25274224).
“There is a real need to automate the manual cleaning step of flexible endoscope reprocessing,” Dr. Alfa said. Technicians are pressured for fast turnaround of endoscopes, she added, and do not always have time to perform manual cleaning according to the instructions for use. Even if technicians had ample time for manual cleaning, their efforts still may not be as good as those of the AECC.
“This could be a pivotal turning point for reprocessing of endoscopes,” Dr. Alfa said, because it is difficult to gain enough friction in narrow channels with standard cleaning methods.
Nanosonics’ next steps are to test the AECC cleaning process on intact flexible endoscope channels, she said.
“This is a solid preclinical benchtop study,” said Mark Gromski, MD, the director of advanced endoscopy and an associate professor of medicine at Indiana University School of Medicine, in Indianapolis. Dr. Gromski, who was not involved in the study, said more data are needed about how well the AECC works to clean scopes used in patient care.
“I think it’s a good steppingstone but is not yet practice-changing,” he said.
Conceptually, the value of automated endoscope cleaning makes sense, particularly in centers that may not have the resources or staff to regularly monitor and retrain staff on the manual cleaning steps of reprocessing, he said, adding that eliminating human error could potentially lead to improved outcomes.
However, even if the value of the AECC is proved in a large clinical trial, Dr. Gromski noted that practice leaders would still need to weigh whether it’s worth adding to their endoscopy suites. Any AECC would require maintenance and dedicated storage space, a potential challenge in smaller endoscopy suites. Also, ongoing training would be required so that use of the new device fits into the unit’s workflow.
“These are not deal-breakers,” he said. “But they are things to consider.”
—Marcus A. Banks
Dr. Alfa reported a financial relationship with Nanosonics. Dr. Gromski reported no relevant financial disclosures.