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

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

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).

Study Overview

• Status: Completed
• Conditions: Colon Polyp
• Intervention / Treatment: Other: Colonoscopy insertion technique used during procedure

• Study Type: Interventional
• Enrollment (Actual): 246
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Harrow, United Kingdom
    • St Mark's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Aged 18 years or older
• Capacity to consent

Exclusion Criteria:

• Pregnancy
• Previous bowel surgery
• Unable to consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Water-alone colonoscopy (water exchange technique); 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; Each arm is using a different colonoscopy insertion technique: either water-alone colonoscopy or water-CO2 colonoscopy.
Active Comparator: Water-CO2 hybrid colonoscopy (modified water immersion technique); 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; Each arm is using a different colonoscopy insertion technique: either water-alone colonoscopy or water-CO2 colonoscopy.

What is the study measuring?

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

Collaborators and Investigators

• Sponsor: London North West Healthcare NHS Trust

Study record dates

Study Major Dates

• Study Start (Actual): March 6, 2021
• Primary Completion (Actual): June 27, 2022
• Study Completion (Actual): June 27, 2022

Study Registration Dates

• First Submitted: May 12, 2020
• First Submitted That Met QC Criteria: January 13, 2021
• First Posted (Actual): January 15, 2021

Study Record Updates

• Last Update Posted (Actual): October 14, 2022
• Last Update Submitted That Met QC Criteria: October 13, 2022
• Last Verified: August 1, 2021

More Information

Terms related to this study

• Keywords: COLONOSCOPY; ENDOSCOPY
• Additional Relevant MeSH Terms: Pathological Conditions, Anatomical; Polyps; Intestinal Polyps; Colonic Polyps
• Other Study ID Numbers: v1.7 30.04.20

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No