Comparison of Right Colon Flat Polyp Detection Rate by Water Exchange Versus Water Immersion-pooled Results of Data File of 3 Published Reports.

GOALS: We tested the hypothesis that water exchange (WE) achieved a significantly higher right colon flat polyp detection rate (rFPDR) than water immersion (WI). BACKGROUND: Current endoscopy methods provide real-time morphology but not histopathology. Flat serrated polyps are difficult to find during colonoscopy. In 2022 2 studies reported that the serrated polyp detection rate (SPDR) significantly inversely predicted the development of interval cancers. In 2021 1 systemic review with meta-analysis showed that WE, but not WI increased SPDR. The relative contributions of WE and WI on rFPDR are unknown. STUDY: Individual patient data from 3 reports comparing air insufflation, WI, and WE were pooled. Multiple logistic regression analysis was used to assess the factors associated with a higher rFPDR. RESULTS: The pooled data showed that the rFPDR of air insufflation, WI, and WE were 15.4%, 14.1%, and 19.4% ( P =0.009), respectively. After adjusting for age and withdrawal time, multiple logistic regression analysis revealed that WE, when compared with WI, was significantly associated with a higher rFPDR (adjusted odds ratio[aOR]=1.53, P =0.002). Analysis of data on pathology and size were omitted to avoid duplicating our earlier publications. CONCLUSIONS: Significantly higher rFPDR was achieved by WE. Water exchange rather than WI merits consideration for use to maximize rFPDR. Removal of flat polyps, and by inference serrated polyps, ensures their optimal management to minimize the occurrence of interval cancers. The potential benefit of WE in maximizing SPDR and minimizing interval cancers deserves evaluation in long-term randomized controlled studies focused on flat polyps detection.

Randomized Trial Comparing Left Colon Mucus Production Using Water vs Saline During Water Exchange Colonoscopy.

INTRODUCTION: Water-assisted colonoscopy increases left colon mucus production; however, the effect of saline on mucus production is unclear. We tested the hypothesis that saline infusion may reduce mucus production in a dose-related manner. METHODS: In a randomized trial, patients were assigned to colonoscopy with CO 2 insufflation, water exchange (WE) with warm water, 25% saline, or 50% saline. The primary outcome was the Left Colon Mucus Scale (LCMS) score (5-point scale). Blood electrolytes were measured before and after saline infusion. RESULTS: A total of 296 patients with similar baseline demographics were included. The mean LCMS score for WE with water was significantly higher than that for WE with saline and CO 2 (1.4 ± 0.8 [WE water] vs 0.7 ± 0.6 [WE 25% saline] vs 0.5 ± 0.5 [WE 50% saline] vs 0.2 ± 0.4 [CO 2 ]; overall P < 0.0001), with no significant difference between the 25% and 50% saline groups. The left colon adenoma detection rate (ADR) was highest in the 50% saline group, followed by the 25% saline and the water groups (25.0% vs 18.7% vs 13.3%), but the difference was not significant. Logistic regression showed water infusion as the only predictor of moderate mucus production (odds ratio 33.3, 95% confidence interval 7.2-153.2). No acute electrolyte abnormalities were documented indicating a safe modification. DISCUSSION: The use of 25% and 50% saline significantly inhibited mucus production and numerically increased ADR in the left colon. Evaluation of the impact of mucus inhibition by saline on ADR may refine the outcomes of WE.

A survey of colonoscopists with and without in-depth knowledge of water-aided colonoscopy.

BACKGROUND AND AIM: Endoscopy featured water-aided colonoscopy (WAC) as novel in the Innovation Forum in 2011. Gastrointestinal Endoscopy published a modified Delphi consensus review (MDCR) that supports WAC for clinical practice in 2021. We tested the hypothesis that experience was an important predictor of WAC use, either as water immersion (WI), water exchange (WE), or a combination of WI and WE. METHODS: A questionnaire was sent by email to the MDCR authors with an in-depth knowledge of WAC. They responded and also invited colleagues and trainees without in-depth knowledge to respond. Logistic regression analysis was used with the reasons for WAC use treated as the primary outcome. Reports related to WAC post MDCR were identified. RESULTS: Of 100 respondents, > 80% indicated willingness to adopt and modify practice to accommodate WAC. Higher adenoma detection rate (ADR) incentivized WE use. Procedure time slots ≤ 30 and > 30 min significantly predicted WI and WE use, respectively. Co-authors of the MDCR were significantly more likely to perform WAC (odds ratio [OR] = 7.5, P = 0.037). Unfamiliarity with (OR = 0.11, P = 0.02) and absence of good experience (OR = 0.019, P = 0.002) were associated with colonoscopists less likely to perform WAC. Reports related to WAC post MDCR revealed overall and right colon WE outcomes continued to improve. Network meta-analyses showed that WE was superior to Cap and Endocuff. On-demand sedation with WE shortened nursing recovery time. CONCLUSIONS: An important predictor of WAC use was experience. Superior outcomes continued to be reported with WE.

Factors associated with prolonged cecal insertion time in patients undergoing water exchange colonoscopy.

BACKGROUND AND AIM: Water exchange is superior to air insufflation in reducing discomfort and increasing adenoma detection during colonoscopy. However, prolonged cecal insertion time is a drawback. This study aims to investigate the factors affecting cecal insertion during water exchange colonoscopy. METHODS: We pooled data from five randomized clinical trials that included patients undergoing water exchange colonoscopy. Logistic analysis was performed to determine the independent factors associated with prolonged cecal insertion time (> 15 min). RESULTS: The cohort included 912 patients (493 men and 419 women) with a median age of 57 years (interquartile range, 49-64 years). The median cecal insertion time was 13.5 min (interquartile range, 10.9-17.0 min). Multivariate logistic regression analysis indicated that female sex, body mass index < 25 kg/m2 , a history of constipation, no sedation, less experienced endoscopist, Boston Bowel Preparation Scale score ≤ 6, infused water volume during insertion ≥ 1000 mL, and scope length at the cecum ≥ 85 cm were associated with prolonged cecal insertion time. With increasing volume of infused water (1000-2000 mL), the median cecal insertion time increased gradually from 11.4 to 23.0 min (P < 0.001). CONCLUSIONS: The current study identified independent factors associated with prolonged cecal insertion time during water exchange colonoscopy. Several factors are modifiable to achieve a shorter insertion time, including better bowel preparation, the use of sedation, more experienced endoscopist, infusing less water during insertion, and maintaining a shorter scope length.

Comparison of Procedural Sequences in Sedated Same-Day Bidirectional Endoscopy with Water-Exchange Colonoscopy: A Randomized Controlled Trial.

Background: Previous studies have favored esophagogastroduodenoscopy (EGD) followed by colonoscopy as the optimal sequence in bidirectional endoscopy (BDE) with air insufflation. However, the optimal sequence in same-day BDE with WE colonoscopy is unclear. Methods: A total of 200 patients undergoing BDE with propofol sedation from May 2018 to January 2021 were randomized to either the EGD-first group (n = 100) or the colonoscopy-first group (n = 100). Results: The EGD-first group required a longer cecal-intubation time (median 16.0 min vs. 13.7 min, p < 0.001) and a lower Boston Bowel Preparation Scale score (8.5 vs. 9, p = 0.030) compared with the colonoscopy-first group. However, the EGD-first group needed a significantly lower dose of propofol (200 mg vs. 250 mg, p < 0.001) and a shorter recovery time (7 min vs. 13.5 min, p < 0.001), resulting in a shorter turnover time of the endoscopy room (39.5 min vs. 42.6 min, p = 0.004). There were no differences in the sedation-related adverse events, patients' satisfaction scores, adenoma-detection rates, or the outcomes of EGD between the two groups. Conclusions: During propofol-sedated BDE, EGD followed by WE colonoscopy was more efficient with a shorter turnover time despite a longer cecal-intubation time (NCT03638713).

Polyp detection and false-positive rates by computer-aided analysis of withdrawal-phase videos of colonoscopy of the right-sided colon segment in a randomized controlled trial comparing water exchange and air insufflation.

BACKGROUND AND AIMS: Water exchange (WE) improves lesion detection but misses polyps because of human limitations. Computer-aided detection (CADe) identifies additional polyps overlooked by the colonoscopist. Additional polyp detection rate (APDR) is the proportion of patients with at least 1 additional polyp detected by CADe. The number of false positives (because of feces and air bubble) per colonoscopy (FPPC) is a major CADe limitation, which might be reduced by salvage cleaning with WE. We compared the APDR and FPPC by CADe between videos of WE and air insufflation in the right-sided colon. METHODS: CADe used a convolutional neural network with transfer learning. We edited and coded withdrawal-phase videos in a randomized controlled trial that compared right-sided colon findings between air insufflation and WE. Two experienced blinded endoscopists analyzed the CADe-overlaid videos and identified additional polyps by consensus. An artifact triggered by CADe but not considered a polyp by the reviewers was defined as a false positive. The primary outcome was APDR. RESULTS: Two hundred forty-five coded videos of colonoscopies inserted with WE (n = 123) and air insufflation (n = 122) methods were analyzed. The APDR in the WE group was significantly higher (37 [30.1%] vs 15 [12.3%], P = .001). The mean [standard deviation] FPPC related to feces (1.78 [1.67] vs 2.09 [2.09], P = .007) and bubbles (.53 [.89] vs 1.25 [2.45], P = .001) in the WE group were significantly lower. CONCLUSIONS: CADe showed significantly higher APDR and lower number of FPPC related to feces and bubbles in the WE group. The results support the hypothesis that the strengths of CADe and WE complement the weaknesses of each other in optimizing polyp detection.

Heat sink effect of underwater polypectomy in a porcine colon model.

BACKGROUND: Underwater polypectomy without the need for submucosal injection has been reported. A heat-sink effect by immersing the polyp in water was proposed but no such experiment has been performed to support the claim. We compared the temperature rise on the serosal side during polypectomy between air- and water-filled colon. METHOD: Freshly harvested porcine colons were placed in a metal tray with cautery electrode pad attached to its bottom. An upper endoscope was used with a cap and a rubber band mounted to the distal end. A mucosal site was randomly selected and identified on its serosal surface with a marker while suction was applied. Suction was applied again and a ligation band was applied to create a polyp. A cautery snare grasped the artificial polyp just below the band. An assistant placed the tip of a thermometer at the marked site on the serosal surface to record the baseline temperature before cautery and the highest temperature during polypectomy. Seven polypectomies in air and underwater were performed. RESULTS: Mean (standard deviation) baseline temperature were 23.3 (0.6) °C and 23.4 (0.6) °C in the air and water groups, respectively. The maximum rise in temperature during polypectomy was 6.1 (4.5) °C and 1.4 (1.0) °C in the air and water groups, respectively (P = 0.004). CONCLUSIONS: The maximum temperature rise during polypectomy was significantly less when polypectomy was performed underwater, supporting the hypothesis that a heat-sink effect does exist during underwater polypectomy.

Computer-Aided Detection False Positives in Colonoscopy.

Randomized control trials and meta-analyses comparing colonoscopies with and without computer-aided detection (CADe) assistance showed significant increases in adenoma detection rates (ADRs) with CADe. A major limitation of CADe is its false positives (FPs), ranked 3rd in importance among 59 research questions in a modified Delphi consensus review. The definition of FPs varies. One commonly used definition defines an FP as an activation of the CADe system, irrespective of the number of frames or duration of time, not due to any polypoid or nonpolypoid lesions. Although only 0.07 to 0.2 FPs were observed per colonoscopy, video analysis studies using FPs as the primary outcome showed much higher numbers of 26 to 27 per colonoscopy. Most FPs were of short duration (91% < 0.5 s). A higher number of FPs was also associated with suboptimal bowel preparation. The appearance of FPs can lead to user fatigue. The polypectomy of FPs results in increased procedure time and added use of resources. Re-training the CADe algorithms is one way to reduce FPs but is not practical in the clinical setting during colonoscopy. Water exchange (WE) is an emerging method that the colonoscopist can use to provide salvage cleaning during insertion. We discuss the potential of WE for reducing FPs as well as the augmentation of ADRs through CADe.

A review of water exchange and artificial intelligence in improving adenoma detection.

Water exchange (WE) and artificial intelligence (AI) have made critical advances during the past decade. WE significantly increases adenoma detection and AI holds the potential to help endoscopists detect more polyps and adenomas. We performed an electronic literature search on PubMed using the following keywords: water-assisted and water exchange colonoscopy, adenoma and polyp detection, artificial intelligence, deep learning, neural networks, and computer-aided colonoscopy. We reviewed relevant articles published in English from 2010 to May 2020. Additional articles were searched manually from the reference lists of the publications reviewed. We discussed recent advances in both WE and AI, including their advantages and limitations. AI may mitigate operator-dependent factors that limit the potential of WE. By increasing bowel cleanliness and improving visualization, WE may provide the platform to optimize the performance of AI for colonoscopies. The strengths of WE and AI may complement each other in spite of their weaknesses to maximize adenoma detection.

Comparison of Right Colon Adenoma Miss Rates Between Water Exchange and Carbon Dioxide Insufflation: A Prospective Randomized Controlled Trial.

GOALS: To test the hypothesis that water exchange (WE), when compared with carbon dioxide (CO2) insufflation, significantly reduces the right colon adenoma miss rate (rAMR) in a blinded randomized controlled trial with cap-assisted colonoscopy. BACKGROUND: The unblinded consecutive group observational data showed that WE significantly decreased rAMR. The unblinded data are limited by potential bias. STUDY: Consecutive patients aged 45 years or more were randomized to undergo insertion with WE or CO2. Withdrawal and polypectomy were performed with CO2 in both groups to the hepatic flexure. The colonoscope was reinserted to the cecum. A second colonoscopist re-examined the right colon. The second colonoscopist was unaware, but made a guess, of the initial insertion method. The number of additional adenomas divided by the total number detected in both examinations equaled rAMR. RESULTS: Among 262 patients (131/group), demographic variables were similar. The body mass index was significantly higher in the WE group. Compared with CO2, WE significantly decreased rAMR [18.0% (33/183) vs. 34.6% (62/179), P=0.0025] and right colon serrated polyp miss rate [17.4% (27/155) vs. 39.3% (33/84), P=0.002]. Multivariate logistic regression analysis showed that WE was an independent predictor of rAMR (odds ratio, 0.42; 95% confidence interval, 0.21-0.86), and so was ≥2 adenomas in the right colon (odds ratio, 2.35; 95% confidence interval, 1.17-4.76). Whether the second colonoscopist guessed the insertion method correctly or not, and demographic and procedure variables were not associated with rAMR. CONCLUSIONS: The randomized controlled trial validated unblinded observational data showing that WE significantly decreased rAMR and right colon serrated polyp miss rate (clinical trial registration number: NCT03845933).

Water-assisted colonoscopy: an international modified Delphi review on definitions and practice recommendations.

BACKGROUND AND AIMS: Since 2008, a plethora of research studies has compared the efficacy of water-assisted (aided) colonoscopy (WAC) and underwater resection (UWR) of colorectal lesions with standard colonoscopy. We reviewed and graded the research evidence with potential clinical application. We conducted a modified Delphi consensus among experienced colonoscopists on definitions and practice of water immersion (WI), water exchange (WE), and UWR. METHODS: Major databases were searched to obtain research reports that could potentially shape clinical practice related to WAC and UWR. Pertinent references were graded (Grading of Recommendations, Assessment, Development and Evaluation). Extracted data supporting evidence-based statements were tabulated and provided to respondents. We received responses from 55 (85% surveyed) experienced colonoscopists (37 experts and 18 nonexperts in WAC) from 16 countries in 3 rounds. Voting was conducted anonymously in the second and third round, with ≥80% agreement defined as consensus. We aimed to obtain consensus in all statements. RESULTS: In the first and the second modified Delphi rounds, 20 proposed statements were decreased to 14 and then 11 statements. After the third round, the combined responses from all respondents depicted the consensus in 11 statements (S): definitions of WI (S1) and WE (S2), procedural features (S3-S5), impact on bowel cleanliness (S6), adenoma detection (S7), pain score (S8), and UWR (S9-S11). CONCLUSIONS: The most important consensus statements are that WI and WE are not the same in implementation and outcomes. Because studies that could potentially shape clinical practice of WAC and UWR were chosen for review, this modified Delphi consensus supports recommendations for the use of WAC in clinical practice.

Cecal intubation time between the use of one-channel and two-channel water exchange colonoscopy: A randomized controlled trial.

BACKGROUND AND AIM: Water exchange (WE) colonoscopy is the least painful insertion technique with high adenoma detection rate but requires a longer intubation time. In the published literature, some investigators used the instrument channel for both infusing and suctioning of water (one channel), while others use colonoscopes with an integrated water-jet channel specifically designed for infusing water (two channel). The aim of this study was to compare cecal intubation time between one-channel and two-channel WE. METHODS: A total 120 patients undergoing colonoscopy from May 2017 to April 2019 at a regional hospital in southern Taiwan were randomized to either a two-channel group (n = 60) or a one-channel group (n = 60). The primary outcome was cecal intubation time. RESULTS: The mean cecal intubation time was significantly shorter in the two-channel group compared with the one-channel group (14.0 ± 4.0 vs 17.4 ± 6.7 min, P < 0.001). The two-channel group required less water infused during insertion (564.8 ± 232.4 vs 1213.3 ± 467.5 mL, P < 0.001) but achieved a significantly higher Boston Bowel Preparation Scale score (8.4 ± 0.8 vs 7.5 ± 1.1, P < 0.001) than did the one-channel group. The adenoma detection rate was comparable in the two groups (50.0% vs 48.3%, P = 0.855). CONCLUSIONS: In comparison with the one-channel WE, two-channel WE showed a shorter cecal intubation time, required less amount of water during insertion, and provided a better salvage cleansing effect. (NCT03279705).

Water Exchange (WE) and Quality Improvement-Enhanced Advanced Adenoma Detection: A Pooled Data Analysis of 6 Randomized Controlled Trials.

INTRODUCTION: Advanced adenomas (≥10 mm in diameter, >25% villous, or high-grade dysplasia), a marker of colorectal cancer risk, are used to stratify patients for closer surveillance. Modern accessories, endoscopes, and age-adjusted evaluation have variable impacts on the advanced adenoma detection rate (AADR). In 1 randomized controlled trial (RCT) comparing air insufflation (AI) with water exchange (WE), the right colon AADR was significantly increased by WE. Four network meta-analyses reported that WE significantly increased overall adenoma detection rate (ADR), but the impact on AADR was not addressed. AIM: The aim of this study was to test the hypothesis that WE significantly increased AADR compared with AI. METHOD: Six Clinicaltrial.gov-registered RCTs were reported by a group of WE investigators. Data including AADR (primary outcome) and overall ADR (secondary outcome) were pooled. RESULTS: A total of 5407 patients were randomized to AI (2699) and WE (2708). Compared with AI, WE significantly increased AADR (5.7% vs. 8.3%, P=0.001) and overall ADR (20.9% vs. 27.4%, P=0.001). CONCLUSIONS: In contrast to published reports, which showed variable impacts on AADR, WE was consistent in increasing AADR in 6 reported RCTs. The pooled data confirm that the impact of WE in increasing AADR was significant. The significantly enhanced overall ADR indicated that WE provided a higher quality outcome than AI. The significant improvement in AADR confirmed WE to be clinically relevant and has finally arrived as a timely addition to colorectal cancer prevention programs.

Feasibility of sedation on demand in Taiwan using water exchange and air insufflation: A randomized controlled trial.

BACKGROUND AND AIM: Completion of colonoscopy without sedation eliminates sedation cost and complications. Reported in the United States and Europe, on-demand sedation is not routine practice in Taiwan. Water exchange (WE), characterized by infusion and nearly complete removal of infused water during insertion, reduces insertion pain compared to air insufflation (AI) during colonoscopy. We evaluated the feasibility of on-demand sedation in Taiwan. In a randomized controlled trial of WE vs AI colonoscopy, we also aimed to determine if WE augmented the implementation by reducing insertion pain and decreasing sedation requirement. METHODS: This prospective patient-blinded study randomized patients to AI or WE (75 patients/group) to aid insertion. The primary outcome was the proportion of patients completing without sedation. RESULTS: In the AI and WE groups, 76.0% and 93.3% (P = 0.006) completed without need for sedation, respectively. The WE group had lower insertion pain score (mean [SD]) (4.0 [2.9] vs 2.1 [2.6], P < 0.001), lower doses of propofol (25.7 [52.7] mg vs 9.1 [35.6] mg, P = 0.012), and less time in the recovery room (3.4 [7.4] vs 1.5 [5.5], P = 0.027) than the AI group. Patient satisfaction scores and willingness to repeat if needed in the future were similar. CONCLUSION: On-demand sedation was feasible in Taiwan. The completion rate without sedation was high in patients (76.0% with standard AI) open to the option (no prior intent to receive the standard of full or minimal sedation). WE augmented the implementation by reducing insertion pain and decreasing sedation requirement without adversely affecting patient satisfaction or willingness to repeat.

An overview of deep learning algorithms and water exchange in colonoscopy in improving adenoma detection.

Introduction: Among the Gastrointestinal (GI) Endoscopy Editorial Board top 10 topics in advances in endoscopy in 2018, water exchange colonoscopy and artificial intelligence were both considered important advances. Artificial intelligence holds the potential to increase and water exchange significantly increases adenoma detection.Areas covered: The authors searched MEDLINE (1998-2019) using the following medical subject terms: water-aided, water-assisted and water exchange colonoscopy, adenoma, artificial intelligence, deep learning, computer-assisted detection, and neural networks. Additional related studies were manually searched from the reference lists of publications. Only fully published journal articles in English were reviewed. The latest date of the search was Aug10, 2019. Artificial intelligence, machine learning, and deep learning contribute to the promise of real-time computer-aided detection diagnosis. By emphasizing near-complete suction of infused water during insertion, water exchange provides salvage cleaning and decreases cleaning-related multi-tasking distractions during withdrawal, increasing adenoma detection. The review will address how artificial intelligence and water exchange can complement each other in improving adenoma detection during colonoscopy.Expert opinion: In 5 years, research on artificial intelligence will likely achieve real-time application and evaluation of factors contributing to quality colonoscopy. Better understanding and more widespread use of water exchange will be possible.

Water exchange colonoscopy decreased adenoma miss rates compared with literature data and local data with CO2 insufflation: an observational study.

BACKGROUND: Reports showed adenoma miss rates (AMRs) of 22.5-27% in the right colon and 23.4-33.3% in the proximal colon. Missed lesions could contribute to postcolonoscopy cancers. Water exchange (WE) with near-complete removal of infused water during insertion increased adenoma detection rate but the impact on AMR had not been reported. We hypothesized that WE could reduce AMRs. Study 1 compared the AMRs of WE with literature data. Study 2 developed local AMR data with CO2 insufflation. METHODS: The lead author attended a research seminar in 2017 on WE colonoscopy. For performance improvement, study 1 was undertaken. When data in study 1 confirmed WE produced a considerably lower AMRs in the right and proximal colon, study 2 with CO2 insufflation was performed. RESULTS: Eighty-six patients completed each study. In study 1, WE removed 89% of infused water upon arrival to the cecum. The AMRs of right colon (17.5%) and proximal colon (15.5%) were considerably lower than those in the literature. Upon completion of study 2, compared with local data of CO2 insufflation, WE showed a significantly lower AMR in the right (17.5% vs. 33.8%, P = 0.034) and proximal (15.5% vs. 30.4%, P = 0.018) colon, respectively. The major limitation was that the investigation consisted of two consecutive observational studies, not a randomized controlled trial (RCT). CONCLUSIONS: WE with near-complete (89%) removal of infused water during insertion significantly decreased AMRs in the right and proximal colon compared with literature data and those of CO2 insufflation in our hands. The provocative data warrant confirmation in a RCT. TRIAL REGISTRATION: NCT03832322 (Retrospectively registered on February 2, 2019).

Endoscopic papillary balloon dilation decreases the risk of bleeding in cirrhotic patients compared with endoscopic biliary sphincterotomy: A national population-based study.

Although endoscopic papillary balloon dilation (EPBD) seems to cause fewer instances of bleeding, there are insufficient data to determine the optimal methods for decreasing the risk of bleeding in cirrhotic patients.In this study, we compared the bleeding risks following endoscopic biliary sphincterotomy (EST) vs EPBD in cirrhotic patients and identified clinical factors associated with bleeding and 30-day mortality.Taiwan's National Health Insurance Database was used to identify 3201 cirrhotic patients who underwent EST or EPBD between January 1, 2010, and December 31, 2013.We enrolled 2620 patients receiving EST and 581 patients receiving EPBD. The mean age was 63.1 ±â€Š13.9 years, and 70.4% (2252/3201) were men. The incidence of post-endoscopic retrograde cholangiopancreatography (ERCP) bleeding was higher among patients treated with EST than those treated with EPBD (EST vs EPBD: 3.5% vs 1.9%). Independent predisposing factors for bleeding included EST, renal function impairment, and antiplatelet or anticoagulant therapy. The overall 30-day mortality was 4.0% (127/3201). Older age, renal function impairment, hepatic encephalopathy, bleeding esophageal varices, ascites, hepatocellular carcinoma, biliary malignancy, and pancreatic malignancy were associated with higher risks for 30-day mortality.To decrease post-ERCP hemorrhage, EPBD is the preferred method in patients with cirrhosis, especially for those who have renal function impairment or are receiving antiplatelet or anticoagulant therapy.

Reduction of multitasking distractions underlies the higher adenoma detection rate of water exchange compared to air insufflation - blinded analysis of withdrawal phase videos.

Background: Experts have hypothesized that a reduction of multitasking distractions and improved bowel cleanliness can explain why insertion water exchange enhances adenoma detection rate. Objective: The purpose of this study was to test the role of both distractions during withdrawal and bowel cleanliness in enhancing adenoma detection rate using coded video records of colonoscopy. Methods: The withdrawal phase of videos of 299 consecutive colonoscopies from two randomized controlled trials comparing water exchange versus air insufflation at a regional hospital in Taiwan were coded. The primary outcome was distractions; activities that preclude full attention being paid to inspection of the mucosa for polyps. A single blinded reviewer collected the data. Results: There were significant agreements in inter-rater reliability indexes. Compared to air insufflation, water exchange had significantly fewer distractions; higher diagnostic yield (intervention time and number), adenoma detection rate, and Boston Bowel Preparation Scale score. Water exchange had a higher withdrawal technique score (predominantly adequacy of cleaning). The association between increased adenoma detection rate and water exchange was mediated by the number of distractions and withdrawal time, but not the Boston Bowel Preparation Scale score. Conclusion: The speculation by experts that a reduction of multitasking distractions underlies the significantly higher adenoma detection rate of water exchange is supported by the current study. Increased bowel cleanliness did not contribute to the increased adenoma detection rate by use of water exchange.