Comparing Bowel Preparation Regimens for Flexible Sigmoidoscopy

Study Overview
=================
Brief Summary
-----------------
Objective and Hypothesis: The investigators objective is to help determine the efficacy of oral and rectal bowel preparation regimens for sigmoidoscopy. The investigators hypothesis is that oral preparation will reduce the amount of repeat rectal enemas required and improve the quality of a bowel exam at the sigmoidoscopy.

Detailed Description
-----------------
Background: Flexible sigmoidoscopy is an accepted screening modality for colorectal cancer, however, it has put significant strain on endoscopy suite resources. It is important that flexible sigmoidoscopies be done completely and efficiently. Cleansing before sigmoidoscopy is important to optimize the diagnostic yield of the exam and for polyp detection rates and other colonic lesions. Rectal enemas have been the mainstay of sigmoidoscopy preparations for many endoscopy suites. Procedure prolongation due to the requirement for additional enemas or more washing of a poorly cleansed colon can put a strain on endoscopy time to complete the procedures. Oral preparations have been a mainstay of colonoscopy cleansing as they allow adequate visualization of the entire colon and are superior to rectal enemas in this regard. Large volume preparations dominate oral colon cleansing. Polyethylene glycol is a large volume solution with an osmotically balanced laxative. Large volume preps are poorly tolerated when compared with small volume preparations. Small volume osmotically active agents can have limitations also, but are being used more frequently with newer agents having a better safety profile. Few large controlled studies have looked at oral preparation being given in sigmoidoscopy. Tolerability of oral prep has had a negative impact on patient compliance with these regimens in colonoscopy. However, rectal enemas also have had a negative impact on sigmoidoscopy experience. Many sigmoidoscopies are incomplete or poorly done due to poor prep. Literature for oral bowel preparation regimens has been done predominantly for colonoscopies. The few studies comparing oral preparations to enemas are done without validated methods to record bowel preparation adequately and objectively (1, 2). The goal of our study is to compare the quality of the bowel preparation with oral preparations and rectal enemas to determine which is best. The investigators plan on determining if the concentration of combustible gases with oral preparations during sigmoidoscopy would be reduced enough to allow for safe electrocautery use during sigmoidoscopy. Hydrogen and methane are two major combustible gases found in a normal colon. These gases can cause explosions in the bowel at the time on sigmoidoscopy if electrocautery is used. The explosive range of hydrogen in air is 4-74%, and for methane this range is 5-15% (3). Levels of combustible gases in the colon have been found to be unsafe in a bowel prepped with two phosphosoda enemas.(4) Several bowel cleansing regimens have been found to be safe for electrocautery by decreasing the concentrations of combustible gases in the colon. Our hypothesis is that a partial oral bowel preparation, will reduce the concentration of combustible gases in the colon to low enough levels to make electrocautery safe during flexible sigmoidoscopy. Objective and Hypothesis: Our objective is to help determine the efficacy of oral and rectal bowel preparation regimens for sigmoidoscopy. Our hypothesis is that oral preparation will reduce the amount of repeat rectal enemas required and improve the quality of a bowel exam at the sigmoidoscopy.

Official Title
-----------------
A Randomized Controlled Study Comparing PicoSalax, Versus PicoSalax and Fleet Enema Versus Fleet Enema Alone for Sigmoidoscopy

Conditions
-----------------
Cathartic Colon

Intervention / Treatment
-----------------
* Drug: Picosulfate sodium,
* Drug: phosphosoda rectal enema
* Drug: Pico-Salax and Sodium phosphate enema


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Consecutive male and non-pregnant female patients >18 years old who require outpatient sigmoidoscopy will be considered for inclusion. Exclusion Criteria: previous colorectal surgery and patients with reduced renal function or other medical conditions that would increase the risk of receiving oral PicoSalx would be excluded from the study.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Picosalax with rectal enema<br>This arm will receive one satchet of Picosalx and a rectal enema before the sigmoidoscopy for their bowel preparation regimen. | Drug: Pico-Salax and Sodium phosphate enema<br>* Pt will take one sachet of Pico-salax the evening prior to procedure and fleet enema 1 hour before leaving home on the morning of the procedure<br>* Other names: Sodium picosulfate;|
| Active Comparator: rectal enema<br>This group of patients will receive only a rectal enema for bowel preparation before their flexible sigmoidoscopy. | Drug: phosphosoda rectal enema<br>* The patient will have an enema inserted into the rectum and the liquid contents of the enema will be squeezed into the rectum. The patient will need to hold in the enema for several minutes then can release it.<br>|
| Active Comparator: Pico-Salax<br>patient will take one sachet of pico-salax | Drug: Picosulfate sodium,<br>* One sachet of picosalax will be given with at least 4 cups of clear fluids.<br>* Other names: PicoSalax;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Quality of colon cleansing | The primary outcomes for this trial will be the quality of colon cleansing in the area of the colon examined. We will use a modified Ottawa bowel preparation scoring system measured at the time of endoscopy | At the time of the flexible sigmoidoscopy, therefore, within 24 hours of flexible sigmoidoscopy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient tolerance questionnaire | The questionnaire delivered one half hour prior to the sigmoidoscopy will ask the patient about acceptability of the bowel prep, the patient's compliance with the bowel prep, if the patient would have the same bowel preparation regimen again for another sigmoidoscopy. We also will look at side effects including wind, incontinence, sleep disturbance, bottom soreness, abdominal tenderness, and nausea. | At the time of the flexible sigmoidoscopy, therefore, within 24 hours of flexible sigmoidoscopy | 
| Requirement for an additional rectal enema. | We also will record whether an additional enema was required to complete an adequate examination. | At the time of the flexible sigmoidoscopy, therefore, within 24 hours of flexible sigmoidoscopy | 
| Maximum length of scope inserted | The maximum scope length reached during the endoscopic procedure will be recorded. We will also record the type of endoscopic equipment used for the sigmoidoscopy, ie. gastroscope, pediatric colonoscope, sigmoidoscope, etc. | At the time of the flexible sigmoidoscopy, therefore, within 24 hours of flexible sigmoidoscopy | 
| Reason for discontinuing further advancement of the scope | The main reason for no further advancement of the sigmoidoscope will be recorded as: inadequate prep, patient intolerance, adequate examination length reached for procedure indication. | At the time of the flexible sigmoidoscopy, therefore, within 24 hours of flexible sigmoidoscopy | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Bowel Evacuants, Purgatives