Comparison of Methods to Distend the Colon During Insertion: CO2, Air Insufflation, Water-aided Colonoscopy

Summary

Insufflation of the colon, usually with room air, is necessary to distend the lumen for exploration. Carbon dioxide (CO2) insufflation instead of room air insufflation (AI) has been shown to decrease symptoms of abdominal pain or discomfort during the procedure and particularly during the following 24 hours. CO2 is is rapidly absorbed by the intestinal mucosa and exhaled through respiration. AI colonoscopy has usually been the reference standard to compare colonoscopy using CO2 insufflation. In two recent articles AI was compared to either CO2 insufflation and Water-aided colonoscopy (WAC), which entails infusion of water to facilitate insertion to the cecum.

WAC can be categorized broadly in Water Immersion (WI) and Water Exchange (WE). In WI water is infused during the insertion phase of colonoscopy, with removal of infused water predominantly during withdrawal. Occasional use of insufflation may be allowed. WE entails complete exclusion of insufflation, removal of residual colonic air pockets and feces, and suction of infused water predominantly during insertion to minimize distention. During the withdrawal phase insufflation is used to distend the colonic lumen.

In the WAC arms of the two mentioned articles the insertion method used was WI, with infusion of water at room temperature or at 37°C. During withdrawal, air insufflation or either air or CO2 insufflation were employed.

Compared to AI, CO2 insufflation and WI (using room air insufflation or CO2 insufflation during withdrawal) were effective in both studies in decreasing sedation requirement, pain and tolerance scores, with patients' higher willingness to repeat the procedure.

Until now no direct comparison has been made within a single study about pain score during colonoscopy using AI, CO2 insufflation, WI/CO2, WE/CO2, WI/AI and WE/AI.

In this study we test the hypothesis that, compared to AI, CO2 insufflation and WAC/CO2-AI methods will decrease pain score during colonoscopy, with reduction of sedation requirement, and that WE will achieve the best result. This comparative study has also the aim to test the respective peculiarities of each method.

Conditions

• Pain
• Colorectal Adenomas
• Colorectal Cancer

Interventions

OTHER

Air Insufflation method.

Air Insufflation method.

OTHER

CO2 insufflation

CO2 insufflation.

OTHER

Water Immersion/CO2

Water Immersion during insertion, CO2 insufflation during withdrawal.

OTHER

Water Exchange/CO2

Water Exchange during insertion, CO2 insufflation during withdrawal.

OTHER

Water Immersion/AI

Water Immersion during insertion, AI insufflation during withdrawal.

OTHER

Water Exchange/AI

Water Exchange during insertion, AI insufflation during withdrawal.

Sponsors & Collaborators

• Presidio Ospedaliero Santa Barbara

  lead OTHER

Principal Investigators

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

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

85 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2013-10-31

Primary Completion

2014-06-30

Completion

2014-07-31

Countries

• United States
• Czechia
• Italy

Study Locations