Water Immersion and Polyp Detection: A Randomized Controlled Trial

Study Overview
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Brief Summary
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We plan to conduct a randomized trial of tandem colonoscopies comparing water infusion and air insufflation for inspection of mucosa on withdrawal. In one randomized group, water infusion will be employed as the first method for mucosal inspection while in a second group, CO2 insufflation will be used first. This study will be different than usual care since the participants will receive two successive or tandem colonoscopies versus one

Official Title
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Water Immersion and Polyp Detection: A Randomized Controlled Trial

Conditions
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Adenoma, Colonic Neoplasms

Intervention / Treatment
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* Procedure: Water Infusion first
* Procedure: CO2 Insufflation First


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: all adults 50 years or older who present for colonoscopy at White River Junction VAMC and Indiana University Exclusion Criteria: includes co-morbid status of ASA III or higher, Inflammatory Bowel Disease (IBD), surgical resection of the large bowel, as well as the use of anticoagulants. Finally, potential subjects who do not report a clear effluent in the most recent bowel movement will be excluded from the study.

Ages Eligible for Study
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Minimum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Screening
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: In one randomized group, water infusion will be employed as the first method for mucosal inspection while in a second group, CO2 insufflation will be used first. This study will be different than usual care since the participants will receive two successive or tandem colonoscopies versus one
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Water Infusion first<br>In this group patients will receive a colonoscopy with water infusion for mucosal inspection and then receive a colonoscopy with CO2 insufflation. | Procedure: Water Infusion first<br>* In this group patients will receive a colonoscopy with water infusion for mucosal inspection and then receive a colonoscopy with CO2 insufflation.<br>|
| Experimental: CO2 Insufflation First<br>In this group patients will receive a colonoscopy with CO2 insufflation for mucosal inspection and then receive a colonoscopy with water infusion. | Procedure: CO2 Insufflation First<br>* In this group patients will receive a colonoscopy with CO2 insufflation for mucosal inspection and then receive a colonoscopy with water infusion .<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Adenoma Miss Rate | Adenoma-level miss rates will be calculated as the number of additional adenomas detected during the second examination divided by the total number of adenomas detected during both examinations | Through procedure, an average of 1 hr | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient-level Miss Rate | Patient-level miss rates will be calculated as the number of patients with one or more adenomas detected during the second examination, divided by the total number of patients with at least one adenoma in either examination | 1 hour or the duration of the procedure | 
| Adenoma < 6mm Detection Rate | Adenoma-level miss rates will be calculated as the number of additional adenomas < 6 mm detected during the second examination divided by the total number of adenomas< 6 mm detected during both examinations. | 1 hour or the duration of the procedure |