CHARLOTTE, N.C.—Changing to disposable duodenoscopes requires a training period but not a steep one, according o a study of a single experienced operator.
“I think all practicing advanced endoscopists who do endoscopic retrograde cholangiopancreatography [ERCP] at some point have to consider doing this transition in one way or another,” whether it is to fully disposable devices or those with disposable tips or caps, said investigator Nasir Saleem, MD, an assistant professor of clinical medicine at Indiana University School of Medicine, in Indianapolis.
Characterizing the Learning Curve
To characterize the learning curve for disposable duodenoscopes, Dr. Saleem and his co-investigators conducted a retrospective review of data from 32 patients who had undergone ERCP by a single experienced operator using the EXALT Model D disposable duodenoscope (Boston Scientific) at a tertiary referral center. They defined an experienced operator as an endoscopist who had completed at least 1,000 procedures.
The learning curve for this device was determined by the number of cases needed to achieve proficiency using a cumulative sum (CUSUM) analysis. The researchers assessed the number of attempts and time to cannulate the desired duct and used the overall mean number of attempts and mean time to cannulation as target values in the respective CUSUM analyses. They defined proficiency as the number of procedures at which an inflection point occurred in a CUSUM graph, with improving operator performance shown by a decrease in the number of attempts and shortening of cannulation time after the defined number of procedures.
Presenting the results at the 2022 annual meeting of the American College of Gastroenterology (ACG) (abstract B0458), Dr. Saleem reported that 26 of the procedures (81%) were classified as American Society for Gastrointestinal Endoscopy complexity level 2 or 3, and six of the 32 patients (19%) had native papillae. Procedures were completed using only disposable duodenoscopes in 28 patients (87%), and a reusable duodenoscope was required to complete the procedure in the remaining four patients.
Procedure-related complications included postprocedural abdominal pain in 13 patients and post-ERCP pancreatitis and intraprocedural/postprocedural bleeding in one patient each.
The researchers found that an inflection of the CUSUM curves occurred at approximately 10 cases for both the number of attempts to cannulate and time to cannulation. They concluded that for experienced ERCP endoscopists, approximately 10 ERCPs can be considered the threshold to achieve proficiency with a disposable duodenoscope.
Procedure-related complications were consistent with those expected with reusable duodenoscopes, and the need to cross over from single-use to reusable duodenoscopes did not appear to be related to the learning curve, Dr. Saleem said.
“We didn’t see a lot of difference in terms of procedure, performance and complications,” he said. Initially “you feel a difference with the maneuverability” of the scope, but “you get used to [it] very easily.”
Volume, Cost and Environmental Factors Need to Be Considered
The study’s findings suggest larger studies and continued research are needed to determine the significance of a learning curve, said Harish K. Gagneja, MD, FACG, AGAF, FASGE, a gastroenterologist with Austin Gastroenterology, in Texas, and the ACG Governor for Southern Texas, pointing to the researchers’ inclusion of only six patients (19%) with native papillae as a significant limitation of the study.
“I think people will have trouble because these are not the regular scopes,” Dr. Gagneja told Gastroenterology & Endoscopy News. “The optics, other controls and the knobs are not going to be that great, so you’re going to have trouble gaining access to the common bile duct—that’s when the rubber meets the road.”
Dr. Gagneja also noted that institutions also should consider volume, rising costs and environmental factors when making a decision about a transition to disposable scopes. In addition, he said, they also should possibly only consider using semi- or fully disposable duodenoscopes in procedures for patients at high risk for infection—those receiving chemotherapy or organ transplant recipients.
“We are all moving towards green endoscopy, and this is opposite of green endoscopy,” he said.
Where Do Disposables Fit Into Practice?
Similarly, Klaus Mergener, MD, PhD, MBA, MASGE, an affiliate professor of medicine at the University of Washington, in Seattle, told Gastroenterology & Endoscopy News that larger prospective studies will need to be conducted to confirm this study’s results, especially since the findings varied from previous research, in which investigators reported an ERCP completion rate of almost 97% when using a single-use duodenoscope (Clin Gastroenterol Hepatol 2020;18[9]:2108-2117.e3).
However, “the bigger and much more important question that still is unanswered is, ‘Where do these disposable scopes fit into our clinical practice, if at all?’” Dr. Mergener said. He likened the transition from reusable to disposable scopes to buying a new car. Sure, the handling and feel may differ to a degree, but it’s still an endoscope, he noted.
The true issue lies with the questions of necessity and quality, according to Dr. Mergener. “Is it really true that these scopes, in terms of their quality of what they can do, are equivalent, or maybe even better than the existing scopes? Because remember, these scopes were built out of concern that with the old scopes, we might transmit infections from patient to patient,” he said.
Dr. Mergener agreed with Dr. Gagneja’s strategy of potentially reserving the use of disposable scopes for patients at the highest risk for infection due to the generally low risk for infection observed in routine ERCP populations. “Possibly for some very high-risk patients, we would use this type of disposable scope in a niche application only for this small subgroup of patients, and we continue otherwise with our existing scopes. That is a narrative that is currently fairly [frequently put forth],” he said. But he noted that “this is a very active field,” and in addition to the development of disposable scopes, various other efforts to minimize infection risk are being explored, such as “improving reprocessing and cleaning of reusable scopes, or possibly creating a different type of reusable scope that could be sterilized.”
—Landon Gray
Dr. Gagneja reported no relevant financial disclosures. Dr. Mergener reported financial relationships with Boston Scientific, Fujifilm, Kate Farms Inc., Pentax and Sebela. Drs. Gagneja and Mergener are members of the Gastroenterology & Endoscopy News editorial board.
This article is from the January 2023 print issue.