Prospective RCT Of Water Exchange (WE) vs. WE Plus Cap-Assisted Colonoscopy

Not Applicable

Completed

Conditions: Water Exchange Colonoscopy
Unsedated Colonoscopy
Cap
Colonoscopy Pain

Brief Summary: This is a study to compare two different, but normally, used methods of colonoscopy in patients undergoing colonoscopy without sedation. There will be two arms in this study: WE (water exchange) control, and WE (water exchange) plus cap (placed at tip of the colonoscope). The patient will prepare himself/herself for the colonoscopy as per normal instructions and he/she will be given the information for the study at that time so that he/she can make a decision to participate in the study. The control method will use water instead of air during insertion of the colonoscope. The study method will use a cap that will fit onto the end of the colonoscope plus water during insertion of the colonoscope. This study will assess if the study method is less painful than the control method.

Detailed Description: This will be a multi-VA site, unblinded investigators, prospective randomized control trial (RCT). Randomization (WE, WE + cap) will be based on computer generated random numbers placed inside opaque sealed envelopes. The envelope (in pre-arranged order set up by statistics consultant) will be opened to reveal the code when the colonoscopist is ready to insert the endoscope to begin the examination. This will be a comparison of two arms (WE, WE + cap) to see which one is less painful.

Patients who are willing to participate will sign an informed consent before starting the colonoscopy procedure. Separate parallel randomization will be set up at each site, stratified type of colonoscopy (screening, surveillance, diagnostic). All subjects will have scheduled unsedated colonoscopy as a result of lack of escort or personal preference for no sedation. Randomization will be set up by statistics consultant.

Control Method: One arm of the study will include unsedated colonoscopy with water exchange (WE) as the control method. Residual air in the colon will be removed and water will be infused to guide insertion through an airless lumen. Infused water will be removed by suction, along with residual fecal debris, predominantly during insertion.

Study method: The other arm will include unsedated colonoscopy with water exchange (WE) and the addition of a cap, fitted to the colonoscope per manufacturer instruction.

Recruitment & Eligibility

Inclusion Criteria

Informed/educated (about pros and cons of the unsedated option) Veterans undergoing:
- diagnostic
- surveillance (follow up of polyps)
- screening (first-time) colonoscopy at participating sites
- choosing scheduled unsedated colonoscopy for any reason (lack of escort, personal preference)

Exclusion Criteria

decline to be randomized
unable to give consent or respond to questionnaires
history of colon surgery
active inflammatory bowel disease
lower gastrointestinal bleeding (except for occult blood or FIT positive in the context of colon cancer screening)
therapeutic colonoscopy (e.g., hemostasis, removal of large polyp)
proctosigmoidoscopy
bidirectional endoscopy
inadequate consumption of bowel preparation
known history of severe diverticulosis or diverticulitis
history of abdominal surgery previously requiring sedation for colonoscopy
current narcotic/anxiolytic medication use
prior unsuccessful experience with unsedated colonoscopy
emergent colonoscopy
evidence of colonic obstruction based on pre-colonoscopy clinical evaluation
current participation in other studies
medical condition that could increase the risk associated with colonoscopy
- active cardiac
- or pulmonary disease
- or other serious disease
medical condition that would preclude a benefit from colonoscopic screening
- cancer
- or any terminal illness
prosthetic heart valve
anticoagulant therapy
nonmedical problems
- psychiatric disorders
- excessive use of alcohol
need for special precautions in performing colonoscopy
- antibiotic prophylaxis
request of on demand sedation

Arm && Interventions

Group	Intervention	Description
Study Method	Study method	The other arm will include unsedated colonoscopy with water exchange (WE) and the addition of a simple commercially available accessory to the colonoscopy device: a cap (Disposable Distal Attachment, Olympus Medical Systems Corp., Tokyo, Japan) fitted to the colonoscope per manufacturer instruction. Residual air in the colon will be removed and water will be infused to guide insertion through an airless lumen. Infused water will be removed predominantly during insertion.
Control Method	Control	One arm of the study will include unsedated colonoscopy with water exchange (WE) as the control method. Residual air in the colon will be removed and water will be infused to guide insertion through an airless lumen. Infused water will be removed predominantly during insertion.

Primary Outcome Measures

Name	Time	Method
Real Time Maximum Insertion Pain	Insertion pain was measured during the duration of the colonoscopy procedure, which lasted on average for about 1 hour	Pain during insertion reported to the unblinded assisting nurse, visual analogue scale, VAS: 0=none, 10=most severe. The highest pain score will be tabulated for analysis. Timing of data collection will be at the discretion of the nurse to minimize bias by colonoscopist behavior.

Secondary Outcome Measures

Name	Time	Method
Insertion Time	Insertion time in minutes was measured during the duration of the colonoscopy procedure, which lasted on average for about 1 hour	Time to cecum (clock display on monitor), faster insertion is a quality marker
Right Colon Adenoma Detection Rate (ADR)	Adenoma Detection Rate (ADR) was measured during the duration of the colonoscopy procedure, which lasted on average for about 1 hour	Right colon Adenoma Detection Rate (ADR) is the proportion of patients with at least one adenoma in the part of the colon between the cecum and the hepatic flexure.
Proportion of Patients With No Insertion Pain	Pain was measured during the duration of the colonoscopy procedure, which lasted on average for about 1 hour	Proportion of patients who report no pain during insertion of the colonoscope.

Locations (3): VA Northern California Health Care System, Mather, CA
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Sacramento, California, United States
VA Palo Alto Health Care System, Palo Alto, CA
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Palo Alto, California, United States
VA Greater Los Angeles Healthcare System, Sepulveda, CA
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Sepulveda, California, United States