Water-only Versus Water-CO2 (Hybrid) Colonoscopy Insertion Technique

Study Overview
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Brief Summary
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The colonoscopy procedure involves insertion of a thin, flexible tube with a tiny camera inside (colonoscope) passed inside the bowel. To allow passage of the colonoscope and adequate visualisation of the lining of the bowel wall a range of techniques can be used. During colonoscopy, you can distend the colon with water, CO2 and air. Air is no longer recommended for gas insufflation during colonoscopy as it causes pain and excess bowel distention. So the options are water and/or CO2 but it is not entirely clear which combination is the best and at what point during the colonoscopy. In practice, a hybrid technique where both CO2 and water are used during the colonoscopy in used. Here, water is exclusively used to help navigate the sigmoid colon with air pockets suctioned and turbid water exchanged with clean water. From splenic flexure to caecum a mixture of water and CO2 is used. The aim of this study is to assess procedure comfort and efficiency of two different colonoscopy insertion techniques: water-alone insertion of the colonoscope (gas insufflation not allowed on insertion; water exchange technique) versus water-CO2 hybrid insertion (water used predominately to splenic flexure with water/CO2 used to caecum; modified water immersion technique).

Official Title
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Water-only Versus Water-CO2 (Hybrid) Colonoscopy Insertion Technique (WAVE): a Randomised Study

Conditions
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Colon Polyp

Intervention / Treatment
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* Other: Colonoscopy insertion technique used during procedure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 18 years or older Capacity to consent Exclusion Criteria: Pregnancy Previous bowel surgery Unable to consent

Ages Eligible for Study
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Minimum Age: 18 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: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Water-alone colonoscopy (water exchange technique)<br>During water-alone colonoscopy, gas insufflation (air or CO2) is not allowed during the insertion of the colonoscope to the caecum. Instead, water is used to facilitate the passage of the scope to the caecum. On withdrawal, CO2 is permitted. | Other: Colonoscopy insertion technique used during procedure<br>* Each arm is using a different colonoscopy insertion technique: either water-alone colonoscopy or water-CO2 colonoscopy.<br>|
| Active Comparator: Water-CO2 hybrid colonoscopy (modified water immersion technique)<br>During water-CO2 hybrid colonoscopy, the operator has access to both water and CO2. In the left colon, predominately water is used to navigate the sigmoid. Once the splenic flexure is reached, a combination of water and CO2 is used to reach the caecum. On withdrawal, CO2 is permitted. | Other: Colonoscopy insertion technique used during procedure<br>* Each arm is using a different colonoscopy insertion technique: either water-alone colonoscopy or water-CO2 colonoscopy.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Insertion time | Time taken to insert the colonoscope | During procedure | 
| Total procedure time | Time taken to insert and withdraw the colonoscope | During procedure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Caecal intubation rate | The proportion of procedures where the caecum is reached | During procedure | 
| Patient discomfort scores | Patients will subjectively assess discomfort scores following the procedure using a Visual Analogue Scale (VAS) which ranges from 0 to 10 where a higher score means a worse outcome. | Immediately after procedure | 
| Loop formation | Scopeguide appearance will be used to evaluate number of loops formed | During procedure | 
| Adenoma detection rate | A measure of the number of adenomas detected during colonoscopy | 1 week after procedure with results of histology | 
| Serrated polyp detection rate | A measure of the number of serrated polyps detected during colonoscopy | 1 week after procedure with results of histology | 
| Number of ancilliary procedures | The number of patient repositions and abdominal pressure episodes required during the procedure | During procedure | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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COLONOSCOPY, ENDOSCOPY