A pilot study to assess feasibility of the water method to aid colonoscope insertion in community settings in the United States

Variability in cecal intubation rate by calculation method: a call for standardization of key performance indicators in endoscopy

BACKGROUND AND AIMS

The cecal intubation rate (CIR) is a widely accepted key performance indicator (KPI) in colonoscopy but lacks a universal calculation method. We aimed to assess whether differences in CIR calculation methods could have an impact on perceived trainee outcomes.

METHODS

A systematic review of CIR calculation methods was conducted on major societal guidelines (United Kingdom, European Society of Gastrointestinal Endoscopy [ESGE] and American Society for Gastrointestinal Endoscopy [ASGE]) and trainee-inclusive studies. Trainees awarded colonoscopy certification between June 2011 and 2016 were identified from the United Kingdom e-portfolio and selected as a validation cohort. For each trainee, both the crude and unassisted CIR were calculated for 50 post-certification procedures using definitions from the 3 international guidelines. The resulting CIRs, and the proportions of endoscopists failing to meet the minimum standard of CIR ≥90%, were then compared across these definitions.

RESULTS

Across the 3 guidelines and 37 eligible studies identified, differences in CIR calculation methodology were demonstrated. These related to adjustment criteria (18 studies) and whether unassisted CIR was stipulated (18 studies). In the validation cohort of 733 trainees (36,650 procedures), the median crude CIR ranged from 96% (ESGE) to 98% (ASGE) (P < .001) and whether unassisted CIR was specified (ESGE, 94%; ASGE, 96%; P < .001). The proportion of trainees failing to achieve CIR ≥90% varied significantly across the different definitions, from 4.9% for the crude ASGE definition to 18.6% for the unassisted ESGE definition (P < .001).

CONCLUSIONS

CIR calculation methods vary among guidelines and research studies; this has an impact on trainee performance measures. With CIR used as an example, this study highlights the need for standardized definitions and calculations of KPIs in endoscopy.

Is water exchange superior to water immersion in detecting adenomas during colonoscopies? Results from a Bayesian network meta-analysis

AIM

Water-assisted colonoscopy (water exchange [WE] and water immersion [WI]) has been shown to improve the adenoma detection rate. However, few studies have compared these two methods head-to-head. Thus, we conducted a network meta-analysis to integrate both direct and indirect evidence comparing the effectiveness of these two procedures.

METHOD

We searched PubMed, Web of Science, and the Cochrane Central Register of Controlled Trials for original papers and abstracts published up to March 2018. Randomized controlled trials (RCTs) reporting data in accordance with the eligibility criteria were included in this study. We performed a Bayesian random effects network meta-analysis with mixed comparisons.

RESULTS

Twenty-nine studies (n = 11464 patients) including 6 direct and 23 indirect comparisons were included in this network meta-analysis. There was a statistically significant difference in the efficacy of adenoma detection when WE was compared with WI (risk ratio [RR]: 1.2, 95% credible interval [CrI]: 1.1-1.3), air insufflation (AI; RR: 1.3, 95% CrI: 1.1-1.4), and carbon dioxide (CO2) insufflation (RR: 1.2, 95% CrI: 1.1-1.5). The different methods were ranked in order from the most to least effective in adenoma detection as follows: WE, WI, AI, and CO2. Moreover, although there were no significant differences in pain scores, willingness to repeat, caecal intubation rate, or total procedure time between WI and WE colonoscopy, WE required a longer caecal intubation time than WI.

CONCLUSION

This network meta-analysis supposes that WE may be superior to WI in detecting adenomas during colonoscopies without affecting other technical features or patient acceptance.

Evidence to suggest adoption of water exchange deserves broader consideration: Its pain alleviating impact occurs in 90% of investigators

AIM: To determine whether observations were reproducible among investigators.

METHODS: From March 2013 through June 2014, 18-85-year-old diagnostic and 50-70-year-old screening patients were enrolled at each center to on-demand sedation colonoscopy with water exchange (WE), water immersion (WI) and insufflation with air or CO₂ for insertion and withdrawal [air or carbon dioxide (AICD)]. Data were aggregated for analysis. Primary outcome: Variations in real-time maximum insertion pain (0 = none, 1-2 = discomfort, 10 = worst).

RESULTS: One thousand and ninety-one cases analyzed: WE (n = 371); WI (n = 338); AICD (n = 382). Demographics and indications were comparable. The WE group had the lowest real-time maximum insertion pain score, mean (95%CI): WE 2.8 (2.6-3.0), WI 3.8 (3.5-4.1) and AICD 4.4 (4.1-4.7), P < 0.0005. Ninety percent of the colonoscopists were able to use water exchange to significantly decrease maximum insertion pain scores. One investigator had high insertion pain in all groups, nonetheless WE achieved the lowest real-time maximum insertion pain score. WE had the highest proportions of patients with painless unsedated colonoscopy (vs WI, P = 0.013; vs AICD, P < 0.0005); unsedated colonoscopy with only minor discomfort (vs AICD, P < 0.0005), and completion without sedation (vs AICD, P < 0.0005).

CONCLUSION: Aggregate data confirm superiority of WE in lowering colonoscopy real-time maximum insertion pain and need for sedation. Ninety percent of investigators were able to use water exchange to significantly decrease maximum insertion pain scores. Our results suggest that the technique deserves consideration in a broader scale.

Water infusion versus air insufflation for colonoscopy

BACKGROUND

Colonoscopy is a widely used diagnostic and therapeutic modality. A large proportion of the population is likely to undergo colonoscopy for diagnosis and treatment of colorectal diseases, or when participating in colorectal cancer screening programs. To reduce pain, water infusion instead of traditional air insufflation during the insertion phase of the colonoscopy has been proposed, thereby improving patients' acceptance of the procedure. Moreover, the water infusion method may improve early detection of precancerous neoplasms.

OBJECTIVES

To compare water infusion techniques with standard air insufflation, specifically evaluating technical quality and screening efficacy, as well as patients' acceptance of the water infusion procedure.

SEARCH METHODS

We searched the Cochrane Colorectal Cancer Group Specialized Register (February 2014), the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 1), Ovid MEDLINE (1950 to February 2014), Ovid EMBASE (1974 to February 2014), and ClinicalTrials.gov (1999 to February 2014) for eligible randomised controlled trials.

SELECTION CRITERIA

We included randomised controlled trials comparing water infusion (water exchange or water immersion methods) against standard air insufflation during the insertion phase of the colonoscopy.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the studies for inclusion and extracted data from eligible studies. We performed analysis using Review Manager software (RevMan 5).

MAIN RESULTS

We included 16 randomised controlled trials consisting of 2933 colonoscopies. Primary outcome measures were cecal intubation rate and adenoma detection; secondary outcomes were time needed to reach the cecum, pain experienced by participants during the procedure, completion of cecal intubation without sedation/analgesia, and adverse events. Completeness of colonoscopy, that is cecal intubation rate, was similar between water infusion and standard air insufflation (risk ratio 1.00, 95% confidence interval (CI) 0.97 to 1.03, P = 0.93). Adenoma detection rate, that is number of participants with at least one detected adenoma, was slightly improved with water infusion (risk ratio 1.16, 95% CI 1.04 to 1.30, P = 0.007). Assuming the fraction of patients undergoing screening colonoscopy who had one or more adenomas detected was 20 per 100 with standard colonoscopy, the use of water colonoscopy may increase the fraction to 23 per 100 individuals. From our findings, it is possible that up to 68,000 more of the 1.7 million outpatient screening colonoscopies performed annually in the United States, could detect adenomas if water infusion colonoscopy was used. In addition, with water infusion participants experienced significantly less pain (mean difference in pain score on a 0 to 10 scale: -1.57, 95% CI -2.00 to -1.14, P < 0.00001) and a significantly lower proportion of participants requested on-demand sedation or analgesia, or both (risk ratio 1.20, 95% CI 1.14 to 1.27, P < 0.00001). Qualitative analysis suggests that water infusion colonoscopy was not associated with a markedly increased rate of adverse events compared with the standard procedure.

AUTHORS' CONCLUSIONS

Completeness of colonoscopy, that is cecal intubation rate, was not improved by water infusion compared with standard air insufflation colonoscopy. However, adenoma detection, assessed with two different measures (that is adenoma detection rate and number of detected adenomas per procedure), was slightly augmented by the water infusion colonoscopy. Improved adenoma detection might be due to the cleansing effects of water infusions on the mucosa. Detection of premalignant lesions during standard colonoscopy is suboptimal, and so improvements in adenoma detection by water infusion colonoscopy, although small, may help to reduce the risk of interval colorectal carcinoma. The most obvious benefit of water infusion colonoscopy was reduction of procedure-related abdominal pain, which may enhance the acceptance of screening/surveillance colonoscopy.

Water-aided colonoscopy

Water-aided methods for colonoscopy include the established water immersion and the recent novel modification of water exchange. Water immersion entails the use of water as an adjunct to air insufflations to facilitate insertion. Water exchange evolved from water immersion to facilitate completion of colonoscopy without discomfort in unsedated patients. Infused water is removed predominantly during insertion rather than withdrawal. A higher adenoma detection rate has been reported with water exchange. Aggregate data of randomized controlled trials suggest that water exchange may be superior to water immersion in attenuating colonoscopy discomfort and optimizing adenoma detection, particularly in the proximal colon.

Water infusion versus air insufflation for colonoscopy: a meta-analysis of randomized controlled trials

BACKGROUND

The aim of this meta-analysis was to determine whether water infusion colonoscopy (WIC) is a more effective diagnostic tool than standard air insufflation colonoscopy (AIC).

METHODS

All articles pertinent to a comparison of water-related methods and air insufflation to facilitate insertion of the colonoscope were retrieved from PubMed, Web of Science, Embase, and Cochrane databases. Pooling results were derived by using the Review Manager Software. Outcomes were assessed using the weighted mean difference (MD) with 95 % confidence intervals (CI) for continuous variables and the odds ratios (OR) with 95 % CI for dichotomous variables.

RESULTS

Eighteen studies involving 2,797 patients were included. WIC was associated with a significantly higher cecal intubation rate than AIC (OR = 1.90; 95 % CI 1.21-2.99; p = 0.005). The intubation time was similar for the two types of colonoscopy, but in WIC there was a significantly lower visual analog scale score for abdominal pain than in AIC (MD = -1.30; 95 % CI -2.03 to -0.58; p < 0.001) without sacrificing the polyp detection rate (OR = 1.17; 95 % CI 0.78-1.77; p = 0.44). Statistically, the patient's willingness to repeat colonoscopy was significantly greater for WIC than for AIC (OR = 1.74; 95 % CI 1.14-2.67; p < 0.01). Furthermore, in the subgroup for trainees, the WIC group achieved a higher cecal intubation rate (OR = 1.83; 95 % CI 1.15-2.93; p = 0.01) and a shorter intubation time (MD = -1.72 min; 95 % CI -3.34 to -0.11; p = 0.04) than the AIC group.

CONCLUSIONS

In contrast to AIC, WIC improved cecal intubation, alleviated abdominal pain, and increased patients' willingness to repeat the procedure.

Water exchange method for colonoscopy: learning curve of an experienced colonoscopist in a U.S. community practice setting

BACKGROUND

Water exchange colonoscopy has been reported to reduce examination discomfort and to provide salvage cleansing in unsedated or minimally sedated patients. The prolonged insertion time and perceived difficulty of insertion associated with water exchange have been cited as a barrier to its widespread use.

AIM

To assess the feasibility of learning and using the water exchange method of colonoscopy in a U.S. community practice setting.

SETTING

Quality improvement program in nonacademic community endoscopy centers.

SUBJECTS

Patients undergoing sedated diagnostic, surveillance, or screening colonoscopy.

METHODS

After direct coaching by a knowledgeable trainer, an experienced colonoscopist initiated colonoscopy using the water method. Whenever >5 min elapsed without advancing the colonoscope, conversion to air insufflation was made to ensure timely completion of the examination.

PRIMARY OUTCOME

Water Method Intention-to-treat (ITT) cecal intubation rate (CIR).

RESULTS

Female patients had a significantly higher rate of past abdominal surgery and a significantly lower ITTCIR. The ITTCIR showed a progressive increase over time in both males and females to 85-90%. Mean insertion time was maintained at 9 to 10 min. The overall CIR was 99%.

CONCLUSION

Use of water exchange did not preclude cecal intubation upon conversion to usual air insufflation in sedated patients examined by an experienced colonoscopist. With practice ITTCIR increased over time in both male and female patients. Larger volumes of water exchanged were associated with higher ITTCIR and better quality scores of bowel preparation. The data suggest that learning water exchange by a busy colonoscopist in a community practice setting is feasible and outcomes conform to accepted quality standards.