Impact of Carbon Dioxide Insufflation and Water Exchange on Post-Colonoscopy Outcomes
Condition: Abdominal Pain
MeSH terms: Abdominal Pain
Study type: Interventional

Summary: 
      Room air insufflated during colonoscopy cannot be completely suctioned, is not easily
      absorbed and remains in the bowel for quite some time, resulting in prolonged bowel
      distension with the discomfort of bloating. Sufferers often experience a sensation of
      fullness and abdominal pressure, relieved only after expulsion of the residual gas, often
      accompanied by colic pain. This can be a lengthy process, and some patients continue to
      report pain as long as 24 hours after the procedure. Abdominal discomfort after colonoscopy
      is an adverse event commonly reported by patients, and definitely associated with the
      procedure. Published reports show that the use of carbon dioxide (CO2) insufflation
      significantly decreases bloating and pain up to 24 hours post-procedure. Preliminary results
      of the investigators' previous study about on-demand sedation colonoscopy in diagnostic
      patients showed that, compared with CO2 insufflation, the water exchange group (WE, infusion
      of water to distend the lumen during insertion; suction of infused water, residual air
      pockets an feces predominantly during insertion) achieved significantly lower real-time
      insertion pain scores. Moreover (insertion-withdrawal method) WE-CO2 had the lowest bloating
      scores just after the procedure and at discharge, comparable with those achieved by CO2-CO2.
      Compared with WE-CO2, the use of WE-air insufflation (AI) showed significantly higher
      bloating scores just after the procedure and at discharge; compared with CO2-CO2 differences
      were significant only at discharge. The investigators decided to conduct a prospective
      randomized controlled trial comparing WE-CO2, WE-AI and CO2-CO2. The investigators will test
      the hypothesis that patients examined by the combination of WE-CO2 will have significantly
      lower bloating scores at specific time points after colonoscopy than those examined using
      WE-AI or CO2-CO2. The investigators will also assess the impact of these three methods on
      patients comfort and activities in the post-procedure period.
    

Detailed description: 
      Design: Prospective double blinded two-center randomized controlled trial. Methods:
      Colonoscopy with CO2 insufflation and water exchange-CO2, water exchange-AI; split-dose bowel
      preparation; on demand-sedation.

      Control method: CO2 insufflation colonoscopy. Study methods: water exchange-CO2 colonoscopy,
      water exchange-AI colonoscopy.

      Population: Consecutive 18 to 80 year-old first-time diagnostic outpatients. After informed
      consent, assignment to control or study arms based on computer generated randomization list
      with block allocation and stratification.
    

Intervention name(s): Carbon dioxide method; Water Exchange-CO2; Water Exchange-AI
Intervention type(s): Other; Other; Other
Intervention description(s): Insufflation with CO2 during insertion and withdrawal phases of colonoscopy.; Insertion using water exchange, withdrawal using CO2 insufflation.; Insertion using water exchange, withdrawal using air insufflation.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Keywords: colonoscopy; carbon dioxide; water exchange; discomfort; colonoscopy pain