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CompletedNCT02041507Updated Apr 13, 2016

Water-aided Colonoscopy vs Air Insufflation Colonoscopy in Colorectal Cancer Screening

An interventional study of Air insufflation method. and Water Immersion method. in Colorectal Cancer, Colorectal Adenomas and Colorectal Polyps, sponsored by Presidio Ospedaliero Santa Barbara. Completed at 4 sites in 3 countries. Open to participants aged 50 Years to 70 Years. Per ClinicalTrials.gov, last updated 2016-04-13.

Sponsored by Presidio Ospedaliero Santa Barbara · Not applicable and Interventional

Phase
Not applicable
Study type
Interventional
Enrollment
1,224
Allocation
Randomized
Ages
50 Years to 70 Years
Sex
All
01

Study summary

The degree of protection afforded by colonoscopy against proximal colorectal cancer (CRC) appears to be related to the quality of the procedure, and the incomplete removal of lesions has been shown to increase the subsequent risk of developing a colon cancer.

Some studies suggest that small polyps with advanced histology are more common in the right than in the left colon (right colon proximal to splenic flexure, left colon distal to the splenic flexure). The average size of polyps in the right colon with advanced pathology or containing adenocarcinoma was ≤9 mm, whereas in the left colon their average size was >9 mm, P\<0.001. Inadequate prevention of right-sided CRC incidence and mortality may be due to right-sided polyps with advanced histology or that harbor malignancy. These presumptive precursors of cancer are smaller and possibly more easily obscured by residual feces, and more likely to be missed at colonoscopy.

Water-aided colonoscopy (WAC) can be subdivided broadly into two major categories: water immersion (WI), characterized by suction removal of the infused water predominantly during the withdrawal phase of colonoscopy, and water exchange (WE), characterized by suction removal of infused water predominantly during the insertion phase of colonoscopy.

In some reports WE appeared to be superior to both WI and air insufflation colonoscopy (AI) in terms of pain reduction and adenoma detection, particularly for \<10 mm adenomas in the proximal colon.

In this multicenter, double-blinded randomized controlled trial (RCT) we test the hypothesis that that WE, compared to AI and WI, will enhance overall Adenoma Detection Rate (ADR) in CRC screening patients. Confirmation of the primary hypothesis will provide evidence that WE enhances the quality of screening colonoscopy.

We also hypothesize that WE may be more effective in detecting proximal colon adenomas than WI and AI, particularly \<10 mm adenomas, thus increasing proximal colon ADR and proximal colon ADR \<10 mm. Confirmation of secondary hypotheses will provide justification for further testing that WE may provide a strategy to improve prevention of colorectal cancer by increasing detection of adenomas in screening colonoscopy.

Unlike previous reports of single colonoscopist studies, the insertion and withdrawal phases of colonoscopy will be done by different investigators. The second investigator will be blinded to the method used to insert the instrument, thus eliminating possible bias about procedure related issues.

Several secondary outcomes will also be analysed.

Read the detailed description

Design: Prospective double-blinded multicenter randomized controlled trial. Methods: Colonoscopy with Air Insufflation, Water Immersion, Water Exchange to aid insertion of colonoscope; split dose bowel preparation. Sedation available at the start of the procedure or on-demand.

Control method: Air insufflation colonoscopy. Study methods: Water Immersion colonoscopy, Water Exchange colonoscopy.

Population: Consecutive 50 to 70 year-old screening patients. After informed consent, assignment to control or study arms based on computer generated randomization list with block allocation and stratification.

Primary outcome: overall Adenoma Detection Rate. Secondary outcomes: proximal colon ADR, Mean Adenomas resected per Procedure (MAP), cecal intubation rate and time, total procedure time (including biopsy and/or polypectomy), maximum pain during colonoscopy assessed during insertion and at discharge, the need for sedation/analgesia and its dosage. In addition loop reduction maneuvers, position changes, abdominal compression, the amount of infused and suctioned water during insertion and withdrawal, and patients willingness to repeat the examination will be evaluated.

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Conditions studied

  • Colorectal Cancer
  • Colorectal Adenomas
  • Colorectal Polyps
  • Pain

Keywords

  • Water-aided colonoscopy
  • Water Immersion
  • Water Exchange
  • On-demand sedation
  • Unsedated colonoscopy
  • Adenoma detection rate
  • Mean adenomas per procedure
03

In context

Colorectal Neoplasms

5,598 studies on the registry are indexed under Colorectal Neoplasms; 1,458 are open to participants now.

This study's enrollment of 1,224 is above the median of 77 across 4,122 interventional studies indexed under Colorectal Neoplasms.

Browse Colorectal Neoplasms studies →

Lead sponsor

Presidio Ospedaliero Santa Barbara is the lead sponsor of 6 studies on the registry; none are open to participants now.

Counted across the registry records on this site, refreshed daily.

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Who can participate

Ages eligible
50 Years to 70 Years
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • consecutive screening patients

Exclusion criteria

Exclusion Criteria:

  • previous colonoscopy within 5 years
  • surveillance colonoscopy
  • previous colorectal surgery
  • indication for a proctosigmoidoscopy or bidirectional endoscopy
  • history of inflammatory bowel disease
  • patient refusal or inability to provide informed consent
  • inadequate consumption of bowel preparation
05

Study design

Phase
Not applicable
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Participant, Investigator)
Enrollment
1,224 participants (actual)

Study arms

  • Active comparator
    Air insufflation method.

    Colonoscopy performed in the standard fashion, with the minimal air insufflation required to aid insertion and allowing for washing as needed. Considered to be standard procedure.

    Other: Air insufflation method.

  • Experimental
    Water Immersion method.

    Infusion of water during the insertion phase of colonoscopy mainly to open the colonic lumen and progress to the cecum immersed in the water environment thus created, without attempting to clear the colon contents. Residual air in the colon will not be removed. Infused water and residual feces will be suctioned back predominantly during withdrawal. Insufflation not used until the cecum is reached. It will be allowed only 3 times and no more than 10 seconds each time (ITT failure if \>3) if the lumen cannot be seen. Withdrawal phase done using air insufflation.

    Other: Water Immersion method.

  • Experimental
    Water Exchange method.

    Insufflation not used until the cecum is reached. Infusion of a sufficient amount of water to render the lumen of the colon a slit to progress with the colonoscope. Part of the infused water will be constantly suctioned back exchanging clean for dirty or hazy water. Air pockets will be always aspirated to collapse the lumen. After cecal intubation as much residual water as possible will be aspirated before beginning the withdrawal phase. During withdrawal residual water and feces will be suctioned. Withdrawal phase done using air insufflation.

    Other: Water Exchange method.

Interventions

  • OtherAir insufflation method.

    Air insufflation colonoscopy.

  • OtherWater Immersion method.

    Water Immersion during insertion, air insufflation during withdrawal.

  • OtherWater Exchange method.

    Water Exchange during insertion, air insufflation during withdrawal.

06

What researchers measure

Primary outcomes

  1. Adenoma Detection Rate.

    Proportion of subjects with at least one adenoma of any size.

    Time frame: 18 months.

Secondary outcomes

  1. Proximal colon Adenoma Detection Rate.

    Proportion of subjects with at least one adenoma of any size in the proximal colon.

    Time frame: 18 months.

  2. Proximal colon <10 mm Adenoma Detection Rate.

    Proportion of subjects with at least one adenoma \<10 mm in the proximal colon.

    Time frame: 18 months.

  3. Mean adenomas resected per procedure.

    Total number of adenomas resected per subject.

    Time frame: 18 months.

  4. Cecal intubation rate.

    Cecal intubation will be defined as passage of the tip of the colonoscope beyond the ileocecal valve so that the medial wall of the cecum proximal to the ileocecal valve will be observed.

    Time frame: 1 hour.

  5. Cecal intubation time.

    Cecal intubation time will be defined as the time for passage of the colonoscope from the rectum to the cecum.

    Time frame: 1 hour.

  6. Total procedure time.

    Total procedure time (including time required for polyp resection or biopsy).

    Time frame: 1 hour.

  7. Maximum pain score recorded during insertion phase of colonoscopy.

    Pain will be measured on a visual analogue scale (VAS) with a score 0=absence of pain, 1-2=simply "discomfort", 10=the worst possible pain. Before the procedure, an endoscopic nurse will explain the VAS scoring system to the patient. Patient will be informed that the request for pain information is not to remind that the examination should be uncomfortable, but to let the colonoscopist be alerted to the need to use maneuvers to minimize discomfort (e.g. loop reduction, removal of colonic content, abdominal compression and/or change in patient position). At regular intervals during colonoscopy (e.g. every 60 seconds) patients will be asked about discomfort or pain. The responses will be recorded, and the maximum pain score noted.

    Time frame: 1 hour.

  8. Pain score at discharge.

    After the procedure and at discharge from the Endoscopy Unit, an assistant nurse blinded to the procedure will ask patients about maximum pain during insertion phase of the procedure using the same VAS when neither the endoscopist nor the assistant nurse who performed the colonoscopy will be present. Patients will be asked to quantify the degree of pain experienced and to place a mark over the VAS accordingly.

    Time frame: 1 hour.

  9. Need for sedation/analgesia and its dosage

    All patients will be offered sedation for the procedure. Patients can accept or decline the medication. If they accept, the procedure will be started with the administration of 2 mg of Midazolam intravenously (minimal sedation). If the patient will choose on-demand sedation, minimal sedation will be offered when pain score reaches ≥2 on the VAS. Patients can accept or decline the offered medication. If they accept, minimal sedation will be administered as described above. To avoid bias by the colonoscopist, sedation medication will be administered based on the patients' confirmation that the pain is no longer tolerable, and not at the discretion of the colonoscopist. The colon segment in which patients requests sedation will be recorded. If additional medication will be required despite the abovementioned maneuvers and/or minimal sedation, it will be provided according to local standards and it will be recorded.

    Time frame: 1 hour.

Other outcomes

  1. Loop reduction maneuvers.

    Applied as needed if advancement of the colonoscope fails.

    Time frame: 1 hour.

  2. Position changes. Position changes. Position changes. Position changes. Position changes.

    Change in patient position as needed if advancement of the colonoscope fails.

    Time frame: 1 hour.

  3. Abdominal compression.

    Compression of abdomen if advancement of the colonoscope fails.

    Time frame: 1 hour.

  4. Amount of water used during the procedure.

    Amount of water infused and aspirated during insertion and withdrawal.

    Time frame: 1 hour.

  5. Patients willingness to repeat the examination.

    Patients willingness to repeat the examination based on overall satisfaction about procedure. Measured at discharge on a yes/no question.

    Time frame: 1 hour.

07

Study locations

4 sites
  • Sepulveda Ambulatory Care Center, VA Greater Los Angeles Healthcare System
    Los Angeles, California 91343, United States
  • Digestive Diseases Center, Vìtkovice Hospital
    Ostrava, 703 84, Czech Republic
  • Digestive Endoscopy Unit, Ospedale S. Barbara
    Iglesias, CI 09016, Italy
  • Division of Gastroenterology, Ospedale Valduce
    Como, CO 22100, Italy
08

References and documents

Publications

  • Leung FW, Amato A, Ell C, Friedland S, Harker JO, Hsieh YH, Leung JW, Mann SK, Paggi S, Pohl J, Radaelli F, Ramirez FC, Siao-Salera R, Terruzzi V. Water-aided colonoscopy: a systematic review. Gastrointest Endosc. 2012 Sep;76(3):657-66. doi: 10.1016/j.gie.2012.04.467. PubMed 22898423 ↗
  • Gupta S, Balasubramanian BA, Fu T, Genta RM, Rockey DC, Lash R. Polyps with advanced neoplasia are smaller in the right than in the left colon: implications for colorectal cancer screening. Clin Gastroenterol Hepatol. 2012 Dec;10(12):1395-1401.e2. doi: 10.1016/j.cgh.2012.07.004. Epub 2012 Jul 24. PubMed 22835574 ↗
  • Cadoni S, Gallittu P, Sanna S, Fanari V, Porcedda ML, Erriu M, Leung FW. A two-center randomized controlled trial of water-aided colonoscopy versus air insufflation colonoscopy. Endoscopy. 2014 Mar;46(3):212-8. doi: 10.1055/s-0033-1353604. Epub 2013 Nov 11. PubMed 24218307 ↗
  • Radaelli F, Paggi S, Amato A, Terruzzi V. Warm water infusion versus air insufflation for unsedated colonoscopy: a randomized, controlled trial. Gastrointest Endosc. 2010 Oct;72(4):701-9. doi: 10.1016/j.gie.2010.06.025. PubMed 20883846 ↗
  • Leung FW. Water-aided colonoscopy. Gastroenterol Clin North Am. 2013 Sep;42(3):507-19. doi: 10.1016/j.gtc.2013.05.006. PubMed 23931857 ↗
  • Rabenstein T, Radaelli F, Zolk O. Warm water infusion colonoscopy: a review and meta-analysis. Endoscopy. 2012 Oct;44(10):940-51. doi: 10.1055/s-0032-1310157. Epub 2012 Sep 17. PubMed 22987214 ↗
  • Cadoni S, Falt P, Rondonotti E, Radaelli F, Fojtik P, Gallittu P, Liggi M, Amato A, Paggi S, Smajstrla V, Urban O, Erriu M, Koo M, Leung FW. Water exchange for screening colonoscopy increases adenoma detection rate: a multicenter, double-blinded, randomized controlled trial. Endoscopy. 2017 May;49(5):456-467. doi: 10.1055/s-0043-101229. Epub 2017 Mar 10. PubMed 28282689 ↗
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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Apr 13, 2016, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT02041507
Lead sponsor
Presidio Ospedaliero Santa Barbara
Responsible party
Sergio Cadoni, M.D. (Responsabile Servizio Endoscopia Digestiva, Presidio Ospedaliero Santa Barbara) — Principal investigator
First posted
Jan 22, 2014
Start date
Feb 2014
Primary completion
Mar 2016
Completion
Apr 2016
Last update
Apr 13, 2016

Study contacts

Sergio Cadoni, MD
principal investigator · S. Barbara Hospital, Iglesias (CI), Italy

Oversight

Data monitoring committee
No
View the source record on ClinicalTrials.gov ↗

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