Efficacy and safety of single use duodenoscopes in comparison to reusable duodenoscopes for endoscopic retrograde cholangiopancreatography: A single center experience

Abstract

BACKGROUND

Single-use duodenoscopes (SDs) were introduced to eliminate exogenous infection risks post-endoscopic retrograde cholangiopancreatography (ERCP).

AIM

To evaluate their efficacy and safety against reusable duodenoscopes (RDs).

METHODS

This was a single-center case control study. All consecutive patients undergoing ERCP using SD between 2020 and 2023 were enrolled. A similar number of patients undergoing ERCP using RD were randomly selected and enrolled. In case of ERCP failure using SD, operators switched to a RD if judged appropriate. The primary outcome was successful ERCP completion rates. The secondary outcomes were rate of difficult biliary cannulation, incidence of crossover from SD to RD, procedure related adverse events, 30-day re-admission rate, and endoscopists' assessment of SD's performance.

RESULTS

A total of 133 patients were enrolled (n = 53 for SD, n = 80 for RD). Baseline characteristics and American Society for Gastrointestinal Endoscopy ERCP complexity grades were comparable between both groups. Successful ERCP completion rates were 88.7% for SD and 95% for RD (P = 0.3). In cases of unsuccessful ERCP with SD, crossover to RD occurred in 3 out of 6 instances, with 2 subsequently succeeding with RD. Rates of adverse events and 30-day readmission were comparable: (1) 13.2% vs 11.2% (P = 0.19); and (2) 15.4% vs 8.9% (P = 0.25), respectively. Median overall endoscopists’ satisfaction with SD was 8 out of 10.

CONCLUSION

The novel SDs demonstrated no difference in efficacy and safety compared to conventional RDs when used to perform a wide range of ERCPs. Nevertheless, further development and study of SDs’ financial and environmental effectiveness is warranted.

Key Words: Endoscopic retrograde cholangiopancreatography; Single-use duodenoscopes; Reusable duodenoscopes; Patient outcomes; Infection control

Core Tip: This study compares the efficacy and safety of single-use duodenoscopes (SDs) with reusable duodenoscopes (RDs) for performing endoscopic retrograde cholangiopancreatography (ERCP). The results showed no significant difference in successful ERCP completion rates (88.7% for SD vs 95% for RD, P = 0.3), adverse event rates, or 30-day readmission rates between the two groups. Despite slightly lower success with SDs, crossover to RD was infrequent and often successful. Endoscopists’ satisfaction with SDs was generally high. These findings suggest SDs are comparable to RDs in terms of safety and efficacy, though further studies on their cost-effectiveness are needed.

INTRODUCTION

The introduction of single-use duodenoscopes (SDs) in late 2019 represented a significant development in the field of advanced endoscopy. This innovative approach was largely prompted by the rising incidence of infectious outbreaks linked to multidrug-resistant organisms (MDROs) associated with the contamination of reusable duodenoscopes (RDs)[1]. A meta-analysis of 15 studies reported a 15.25% contamination rate of reprocessed patient-ready duodenoscopes[2]. Concurrently, there were numerous reports of post-endoscopic retrograde cholangiopancreatography (ERCP) infections, attributable to duodenoscope-transmitted MDROs, despite compliance with duodenoscope reprocessing guidelines[3-6]. Among the most serious and frequently reported organisms are carbapenem-resistant Enterobacteriaceae (CRE)[5], and Pseudomonas aeruginosa[7]. In a case series, CRE bacteremia from contaminated duodenoscopes was deadly in two out of nine cases[5]. These incidents likely contribute to an underestimated overall ERCP-related mortality rate, estimated at 0.3%, as directly linking deaths to contaminated duodenoscopes is challenging[8]. Given the severity of MDRO infections and the high number of ERCPs performed annually, addressing even rare cases of duodenoscope cross-contamination was necessary. Several factors contributed to residual contamination of reprocessed duodenoscopes, including miscommunication regarding reprocessing procedures, the intricate design of duodenoscopes, unnoticed damages, heavy microbial contamination post-procedure, and the potential formation of biofilms[9-11]. Under the direction of the United States Food and Drug Administration (FDA), various strategies were explored to minimize or eliminate the risk of exogenous ERCP-related infections. Ultimately, two sterile single-use duodenoscope models, the EXALT Model D (Boston Scientific Corporation) and the Ambu Scope Duodeno, were introduced and approved by the FDA[12,13].

Several post marketing studies including a small randomized trial[14] and multiple multicenter case series have evaluated the efficacy and safety of EXALT Model D single-use duodenoscope[15-18]. So far, all studies reported reassuring safety, technical performance, and endoscopist satisfaction ratings[15-18]. In this study, we aimed to compare the performance and safety of SDs EXALT Model D to their reusable counterparts. This study is intended to provide real-world insights from a tertiary care center.

MATERIALS AND METHODS

Study design

This was a single-center case control study conducted to investigate the performance and safety of a single-use duodenoscope (EXALT Model D, Boston Scientific Corporation, Massachusetts). Written informed consent for ERCP was obtained from all patients. The study was approved by the Institutional Review Board. All adult patients (18 years and older) who underwent ERCP using the single use duodenoscope from its adoption (January 2020) through March 2023 were identified (n = 53). For comparison, all ERCP procedures performed using the Olympus treated-jute fiber-180 reusable duodenoscope (RD) in 2022 were identified (n = 80). All identified cases were included in the final analysis (n = 133). Indications for ERCP included biliary obstruction due to stone(s), mass, or unclear etiology; biliary stent removal or exchange; cholestatic liver injury; others.

Collected variables

Relevant patient demographic and clinical data were collected from the medical records, including gender, age, body mass index (BMI), current anti-coagulants use, age-adjusted Charlson Comorbidity Index (CCI), indication for ERCP, previous sphincterotomy, and history of pre-procedural MDRO infection. The following procedural parameters were recorded: American Society for Gastrointestinal Endoscopy (ASGE) grade for the complexity of ERCP procedures[19], total procedure time in minutes, incidence of crossover from single-use to RD, ERCP completion rate, reason for procedure incompletion or crossover to RD, and adverse events. We also determined the rate of 30-day re-admission in both groups. In addition, the overall performance of the single-use duodenoscope was assessed based on endoscopists’ subjective rating. All endoscopists rated their preference in using the single-use duodenoscope for 8 different ERCP maneuvers (not preferred/neutral/preferred) relative to the RD, 21 device performance characteristics [scale of 1 (not preferred) to 5 (comparable with RD)], and their median overall satisfaction with the single-use duodenoscope during the procedure [scale of 1 (unsatisfied) to 10 (very satisfied)].

ERCP procedure and choice of duodenoscope

All ERCP procedures were performed by one of five participating experienced endoscopists, each with an annual ERCP caseload exceeding 100. All procedures were performed under general anesthesia. Non-steroidal anti-inflammatory drug suppositories were administered as post-ERCP pancreatitis prophylaxis when not contraindicated.

Start and stop times of the procedure were recorded. Indications to use the single-use duodenoscope were based on a hospital protocol which included a history of MDRO infection, immunocompromised state, or endoscopists' discretion. The single-use duodenoscope was connected to a dedicated EXALT processor. No modifications were made to the devices prior to their use. As this study coincided with the introduction of SDs at our hospital, none of the endoscopists had prior experience with this device. To facilitate the transition, the supplier provided representatives and coaches during the first month of the single-use duodenoscope adoption to supervise and assist the endoscopists. This ensured a standardized approach during the early adoption phase.

Outcomes and definitions

The primary outcome was successful ERCP completion for the intended clinical indication without the need to switch to the RD. The secondary outcomes included reported difficult biliary cannulation (based on endoscopists’ subjective assessment), incidence of crossover from single-use to RD, procedure related adverse events, 30-day re-admission rate, and subjective ratings on 8 ERCP maneuvers (not preferred/neutral/preferred relative to the RD), 21 device performance characteristics [Likert scale of 1 (not preferred) to 5 (comparable with RD)], and median overall satisfaction with the single-use duodenoscope during the procedure [Likert scale of 1 (unsatisfied) to 10 (very satisfied), followed by the option "If you answered 5, specify reason"][16,17]. Adverse events were defined as events that prevented completion of the procedure and/or resulted in unintended harm to the patient by prolonging their hospital stay or requiring extra treatments, including mucosal ulceration, perforation, bleeding, or post-ERCP pancreatitis.

Statistical analysis

Descriptive statistics included mean and standard deviation for age and BMI, procedure completion rates, median ratings for overall satisfaction. Comparison between continuous variables was done using t-test. χ² test was used to compare qualitative variables. Statistical analyses were performed using Graph Pad Prism version 9.0.0 (Boston, MA, United States, www.graphpad.com).

RESULTS

Patient characteristics

A total of 133 patients (53.3% males; mean age 69.5 years) were included in the study. During the study period, each of the 133 patients underwent a single ERCP procedure, which was analyzed. Of the total cohort, 53 ERCPs were attempted using the single-use duodenoscope, and 80 using the RD. Baseline characteristics of patients included in the study are shown in Table 1. In brief, the distribution of comorbidity class based on the CCI (low, moderate, or high) did not differ between the two groups, nor did age, gender, BMI, and anticoagulation use. Finally, ASGE grade for ERCP complexity was similarly distributed between both groups. The most common indications for ERCP were cholestatic liver injury (34.5%), and bile duct stones (28.1%) (Supplementary Table 1).

Table 1 Baseline patients’ characteristics and endoscopic retrograde cholangiopancreatography details, n (%).

Characteristics	Total cohort (n = 133)	Single-use duodenoscope (n = 53)	Reusable duodenoscope (n = 80)	P value
Age (years), mean ± SD	69.54 ± 13.3	69.8 ± 12.4	68.9 ± 14.4	0.72
Gender (male, %)	53.3	56.6	51.3	0.59
Body mass index (kg/m2), mean ± SD	28.2 ± 7.9	30.5 ± 9.9	27.2 ± 6.3	0.07
Diabetes mellitus	32 (24)	16 (30.1)	16 (20)	0.2
Use of anti-coagulants	21 (15.7)	10 (18.8)	11 (13.7)	0.42
CCI score
Low, CCI = 0	13 (9.8)	2 (3.7)	11 (13)	0.23
Moderate, CCI = 1–2	50 (37.6)	18 (34)	32 (40)	0.71
High, CCI > 2	70 (52.6)	33 (62)	37 (47)	0.09
Indications for endoscopic retrograde cholangiopancreatography
Choledocholithiasis	41 (30.8)	18 (34)	23 (28.7)
Mass	16 (12)	6 (11.3)	10 (12.5)
Cholestatic liver injury	47 (35.3)	17 (32)	30 (37.5)
Stent exchange/removal	16 (12)	8 (15)	8 (10)
Others	13 (9.8)	4 (7.5)	9 (11.2)
American Society for Gastrointestinal Endoscopy grade				0.37
Grade 1, 2	106 (79.7)	44 (83.7)	62 (77.3)
Grade 3, 4	27 (20.3)	9 (16.3)	18 (22.7)
Mean total procedure time (minutes)	47.1	48.8	45.9	0.6

CCI: Charlson Comorbidity Index.

Clinical outcomes

ERCP was successfully completed in 47 out of 53 (88.7%) patients in the single-use duodenoscope group compared to 76 out of 80 (95%) patients in the RD group (P = 0.3). Reasons for ERCP failure in the single-use duodenoscope group were inability to cannulate the ampulla (n = 2), obstructive duodenal mass (n = 1), gastric outlet obstruction (n = 1), scope malfunction (n = 1), and failure to pass a guidewire through an obstructed biliary stent (n = 1). Out of these six initially unsuccessful ERCPs, three procedures included a crossover to the RD, resulting in the successful completion of two out of the three. In the RD group, reasons for ERCP failure were inability to cannulate the ampulla due to neoplastic infiltration (n = 1) and peri-ampullary diverticulum (n = 1), failure to locate the ampulla (n = 1), and bleeding from the gastroesophageal junction (n = 1). Difficult biliary cannulation was reported in 11 cases (20.7%) in SD group compared to 11 cases (13.7%) in the RD group (P = 0.29). Finally, the mean total procedure time was similar between the two groups (SD: 48.8, RD: 45.9; P = 0.6). Figure 1 depicts the main measured outcomes.

Figure 1 Depiction of clinical outcomes. RD: Reusable duodenoscope; SD: Single-use duodenoscope.

Adverse events

Adverse events developed in 7 cases (13.2%) in the single-use duodenoscope group and 9 (11.2%) in the RD group (P = 0.19). In the single-use duodenoscope group, three patients experienced post-ERCP pancreatitis, two patients developed mild post-sphincterotomy bleeding, and one patient developed a gastric ulcer caused by direct trauma upon duodenoscope withdrawal. The latter was discovered when the patient developed melena and acute on chronic anemia the day following ERCP. An upper endoscopy was subsequently performed revealing a 5 cm long oozing linear gastric ulcer extending from the gastro-esophageal junction to gastric body along the lesser curvature (Figure 2). Hemostasis was achieved with the deployment of 3 Endo clips (Figure 3). Finally, in the single-use duodenoscope group, one patient developed a perforation which was secondary to balloon dilation by gastroscope to overcome severe gastric outlet obstruction. Table 2 depicts adverse events encountered in both groups.

Figure 2 An upper endoscopy revealed a 5 cm long linear gastric ulcer, extending from the gastroesophageal junction to the gastric body along the lesser curvature, with active oozing.

Figure 3 Hemostasis was successfully achieved through the deployment of three Endo clips.

Table 2 Adverse events, n (%).

	Single-use duodenoscope	Reusable duodenoscope
Total	7 (13.2)	9 (11.2)
Post-endoscopic retrograde cholangiopancreatography pancreatitis	3 (5.6)	5 (6.2)
Post-sphincterotomy bleeding	2 (3.8)	2 (2.5)
Traumatic bleeding	1 (1.9)	1 (1.2)
Perforation	1 (1.9)	1 (1.2)

Traumatic bleeding refers to bleeding from direct duodenoscope traumatic injury to the mucosa.

All cases of post-ERCP pancreatitis in the single-use duodenoscope group were classified as mild according to the revised Atlanta classification. None of these cases required intensive care unit admission, and all were managed conservatively. Bleeding events in the single-use duodenoscope group were also classified as mild, as they were endoscopically controlled with no need for blood transfusions or further interventions.

Readmission rates

There was no significant difference in 30-day readmission rates between the single-use and RD groups, with rates of 15.4% and 8.9%, respectively (P = 0.25). In the total cohort, only five re-admissions were because of ERCP related complications- four in the single-use duodenoscope group [recurrent biliary obstruction (n = 2), post-sphincterotomy bleeding (n = 1), and post-ERCP pancreatitis (n = 1)] and one in the RD group related to post-ERCP pancreatitis.

Single-use duodenoscope performance rating

For 6 out of 8 rated standard ERCP maneuvers, all five endoscopists gave a "neutral" rating. For the other two (cannulation of pancreatic duct and placement of pancreatic stents) 2 out 5 endoscopist gave a rating of "not preferred" and the rest rated as "neutral". Median ratings of 5 (range: 1-5) were documented for 10 out of 21 ERCP maneuvers (47.6%) tested; the other 11 maneuvers received a median rating of 4.0. The median overall satisfaction with the single-use duodenoscope was rated as 8.0 (range: 1-10) (Tables 3 and 4).

Table 3 Operators’ ratings of single-use duodenoscope performance relative to the reusable duodenoscope per endoscopic retrograde cholangiopancreatography maneuvers.

Maneuver	Preferred	Neutral	Not preferred
Biliary sphincterotomy	-	100% (5/5)	-
Cannulation of main bile duct	-	100% (5/5)	-
Cannulation of pancreatic duct	40% (2/5)	60% (3/5)	-
Clearance of bile duct stones	-	100% (5/5)	-
Placement of biliary stents	-	100% (5/5)	-
Removal of biliary stents	-	100% (5/5)	-
Placement of pancreatic stents	40% (2/5)	60% (3/5)	-
Balloon dilation of biliary strictures	-	100% (5/5)	-

Five is the total number of participating operators all of whom completed this rating.

Table 4 Median ratings for single-use duodenoscope performance characteristics.

Performance characteristics	Median rating (range)
Ease and ability to intubate the esophagus	4 (1-5)
Ease and ability of traversing the stomach and the pylorus	4 (1-5)
Inadvertent slippage out of the duodenum	4 (1-5)
Navigation/pushability (overall from insertion to the deepest point of advancement into duodenum)	4 (1-5)
Predictability of range of motion	4 (1-5)
Suction performance	5 (1-5)
Ability to select short/long position as needed	4 (1-5)
Ease and ability to examine luminal mucosa where necessary	5 (1-5)
Stability of scope during cannulation of papilla	4 (1-5)
Elevator function	5 (1-5)
Ability to selectively cannulate	5 (1-5)
Tip control and deflection at time of cannulation	5 (1-5)
Ease of controlling and maintaining position during sphincterotomy	5 (1-5)
Position of the device in the field of view	5 (1-5)
Visualization/location of important landmarks on monitor	4 (1-5)
Maintenance of grip on wire by elevator	5 (1-5)
Elevator strength and ability to pass rigid device into common bile duct or pancreatic duct	5 (1-5)
Torquability of scope and ability to orient tip of scope in direction of push/pull	4 (1-5)
Ease and ability of passing/advancing ancillary devices through the channel of single use duodenoscope	5 (1-5)
Image quality/appearance/brightness	4 (1-5)
Ease and ability of duodenoscope withdrawal	4 (1-5)
Overall satisfaction	8 (1-10)

DISCUSSION

This study assessed the safety and performance of the EXALT Model D single-use duodenoscope in comparison to the conventional RD in the context of ERCP. No difference was found in terms of successful ERCP completion using the single-use duodenoscope compared to RD. Both duodenoscopes were associated with a similar incidence of adverse events. Moreover, the median overall endoscopists' satisfaction with the use of the single-use duodenoscope was 8/10 on a scale of 1 to 10 (best). In the mid-2010s, there was an increasing recognition of outbreaks of MDROs infections linked to duodenoscopes[20,21]. These outbreaks were attributed to challenging factors, including the intricate design of duodenoscopes, extremely narrow safety margins associated with reprocessing, and the potential for biofilm formation[20,21]. To address these challenges, disposable duodenoscope endpieces as well as fully disposable SDs were developed[16]. While disposable duodenoscope elevator caps proved to be effective in reducing contamination following high-level disinfection compared with standard scope designs[22], some have been recently linked to malfunctioning prompting FDA to issue a warning letter[23]. On the other hand, the EXALT model D single-use duodenoscope has gained wider adoption based on reassuring efficacy and safety data from multicenter studies[15-18]. While these disposable duodenoscopes can be of critical benefit in certain scenarios—such as in immunocompromised patients or situations where effective reprocessing might not be guaranteed, or in emergencies where the availability of regular duodenoscopes can be limited[18,24]—they are not free of disadvantages. These include their inferior efficacy compared to RDs in certain technically challenging ERCPs as indicated by numerous reported cases of success only after crossover to the RD[16-18]; the current high cost compared with the reusable or partially reusable (with disposable endcaps) counterparts[25]; their potential adverse impacts on the environment as recycling programs are not yet widely available[26]. Early post-marketing studies indicate a successful ERCP completion rate using the single-use duodenoscope ranging from 95% to 96.7%, across varying levels of ERCP complexity[15,16]. In addition, efficacy and safety outcomes did not differ based on endoscopists’ experience[17]. More recently, a global case series of over 500 patients reported a slightly lower overall success rate with the single-use duodenoscope at 91.3%[18], closer to what we observed (88.6%). Most published data come from major academic centers, where higher overall resources and expertise may account for differences in reported success rates. Like previous studies, we encountered cases (n = 2) where ERCP completion required crossover from single-use to RD. Bruno et al[18] reported 37/551 or 6.7% incidence of crossover to RD. Of those, 70% were successfully completed with the RD. This underscores that, at this stage, the single-use duodenoscope cannot universally substitute the RD. This may be attributed to the slightly limited maneuverability and torque of the single-use duodenoscope, issues with image quality or device functionality, and/or the presence of a learning curve despite extensive ERCP experience. For the latter, a retrospective review of 32 ERCPs using single-use duodenoscope suggested 10 ERCPs as the threshold to achieve proficiency[27]. However, the study reported an apparent lack of association between a learning curve and crossover to RD[27]. It is noteworthy that all published studies, including ours, utilized the first-generation EXALT-D single-use duodenoscope. Currently, second and third generations have been released, which might have addressed the previously reported limitations[28]. The safety profile of SDs has consistently been found to be comparable to that established for RDs[16-18]. The reported rate of serious adverse events associated with SD ranged from 4.1% to 7.8%[15-18]. Our results revealed a slightly higher percentage, but one of the adverse events (perforation) was unrelated to the duodenoscope, as it occurred because of balloon dilation of a gastric outlet stricture. In single-arm studies, having the RD safety profile as a reference standard might be somewhat limited or biased, as the largest assessment of RD-related adverse events was based on a review of results published between 1977 and 2006[29], and those rates might have improved over the past 17 years. Our findings strongly support the broader adoption of SDs, especially in clinical settings where eliminating the risk of exogenous ERCP-related infections is crucial. In addition, in situations where strict adherence to reprocessing techniques can be difficult, SDs serve as a great alternative. However, it is important to note that SDs do not eliminate the risk of endogenous infections, which is an inherent risk associated with ERCP[16]. Finally, available studies have not adequately explored the financial and ecological effectiveness of these devices, which warrants further research. Our study has several strengths and limitations. Unlike most prior studies, we conducted a comparison of ERCP outcomes between SDs and RD within a single center, performed by the same endoscopists. This provides a more accurate assessment of SDs’ performance and safety relative to RDs. Moreover, our findings may offer greater generalizability to university-affiliated, low to moderate volume centers, like ours. This is particularly noteworthy, given that the majority of published data comes from experiences in multi-academic center settings[16-18]. Another strength of our study is the absence of funding from the manufacturer of the examined single-use duodenoscope neither for the study nor for any of the investigators. This contrasts with most published studies, minimizing investigator bias. The main limitations of the study are the retrospective design and the relatively small sample size. In addition, our study only included experienced endoscopists, making this study potentially not generalizable to endoscopists with low experience or advanced endoscopy trainees. Another significant limitation of our study is the absence of cost analysis, which is critical in evaluating the adoption of SDs. Based on recent analyses, the per-procedure cost of the Exalt Model D single-use duodenoscope is approximately $3000, which is higher compared to RD’s, even after accounting for reprocessing costs like high-level disinfection or ethylene oxide sterilization[30]. RDs incur base reprocessing costs ranging from $200 to $1180 depending on the method used[30]. However, the single-use duodenoscope's cost-effectiveness lies in its ability to prevent duodenoscope-associated infections entirely, eliminating costs related to infection treatment and outbreak control. Moreover, insurance and federal reimbursement mechanisms for innovative devices can offset the upfront cost, making SDs a financially viable option in specific healthcare settings[30]. More studies are needed to delineate the comprehensive cost-effectiveness of SDs.

CONCLUSION

In conclusion, in line with previous studies, experienced endoscopists performed a wide range of ERCPs using SDs with no apparent difference in the success rate and safety compared to RDs. Nevertheless, the need for randomized trials comparing the most recent generation of SDs to RDs remains, and studying their financial and environmental effectiveness is warranted.