Effect of Single Dose of 2L PEG on Bowel Preparation in Average-risk Patients Undergoing Colonoscopy

Study Overview
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Brief Summary
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Adequate quality of bowel preparation(BP) is important for colonoscopy. Several guidelines recommend that split-dose of 4L PEG should be used as a standard regime for BP. However, the high-volume PEG still results in lower compliance to the regime and increased cost. Some high risk factors for inadequate BP have been identified, including old age, constipation, diabetes, the use of narcotics and prior history of inadequate BP. For average-risk patients without the high risk factors, the procedure of BP could be easier. In the previous study, with the use of single dose of 2L PEG, more than 90% of average-risk patients achieved adequate BP. Here investigators hypothesized that compared with the standard split dose of 4L PEG, single dose of 2L PEG may be not inferior in BP quality while may be accompanied with better tolerability.

Official Title
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Effect of Single Dose of 2L PEG on Bowel Preparation in Average-risk Patients

Conditions
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Health Behavior

Intervention / Treatment
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* Drug: Single dose of 2L PEG
* Drug: Split dose of 4L PEG


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing colonoscopy; Patients with average risks for inadequate BP (Patients were identified average-risk if they did not meet any factor of the following risk factors): Constipation Diabetes Parkinson's disease History of stroke or spine cord injure Prior history of inadequate bowel preparation BMI>25 Use of tricyclic antidepressant or narcotics Exclusion Criteria: History of colorectal resection; Suspected colonic stricture or perforation; Incomplete or complete bowel obstruction; Use of prokinetic agents or purgatives within 7 days; Toxic colitis or megacolon; Pregnancy or lactation; Unable to give informed consent; Haemodynamically unstable.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Single dose of 2L PEG<br>2 L of PEG solution was used on the day of colonoscopy. | Drug: Single dose of 2L PEG<br>* Patients at average risk for inadequate BP were given instructions for bowel preparation through phone call a day before scheduled colonoscopy. Patients began to drink 2 L of PEG 4-6 hours before colonoscopy at a rate of 250 mL every 15 minutes.<br>|
| Active Comparator: Split-dose of 4L PEG<br>Split-dose of 4l PEG was used before and on the day of colonoscopy | Drug: Split dose of 4L PEG<br>* All patients at average risk for inadequate BP were given instructions for bowel preparation through phone call a day before scheduled colonoscopy. the participants began to drink the first 2 L of PEG at 7:00-9:00 PM on the day before colonoscopy at a rate of 250 mL every 15 minutes. On the day of the procedure, patients took the remaining 2 L 4-6 hours before colonoscopy.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of adequate bowel preparation(defined as a total BostonBowel Preparation Score ≥6 with each segmental BBPS≥2) | The adequacy of bowel preparation is defined as Boston Bowel Preparation Scale (BBPS), a 4-point scoring system applied to each of 3 broad regions of the colon: the right side, the transverse section, and the left side. They were summed to give the total BBPS score, which ranged from 0 to 9.The withdrawal procedure was recorded by vedios. The BBPS and segmental scores in each segment were judged by one endoscopist who was familiar with the criteria of BBPS and blinded to group allocation. | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Polyp detection rate |  | 1 year | 
| Rate of adverse events | adverse events, such as vomiting, nausea, headache, abdominal pain | 1 year | 
| Cecal intubation rate |  | 1 year | 
| Cecal intubation time |  | 1 year | 
| Withdrawal time |  | 1 year | 
| Willingness to repeat bowel preparation | The number of patients have a willingness to undergo a repeated bowel preparation if needed | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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PEG, Bowel preparation, Colonoscopy