Consecutive eligible patients will be enrolled and written informed consent will be
obtained from all participants. Routine blood investigations will be sent. Patients with
chronic heart failure will be classified based on ejection fraction into 2 groups (EF </>
40%), patients with chronic kidney disease will be classified based on KDIGO
classification system into grade I-V. Patients with chronic liver disease will be
classified according to the child pugh scoring system into three groups (Child A, B and
C). All patients will be undergo bowel preparation under supervision. The patients will
be given 10 mg of bisacodyl, the night before colonoscopy. A PEG sachet (137.15 g)
containing polyethylene glycol (118 g), sodium chloride (2.93 g), potassium chloride
(1.484 g), sodium bicarbonate (3.370 g), and anhydrous sodium sulfate (11.36 g) will be
constituted into 2 L solution and used for bowel preparation.
Patients will receive 1 L of PEG solution between 10 PM and 11 PM the day before and 1 L
of PEG solution between 6 AM and 7 AM on the day of colonoscopy. Clear liquids will be
allowed after the completion of the last bowel preparation until the start of the
procedure. Liquid diet includes soups, fruit juices, rice kanji, or porridge in liquid
consistency, and clear liquids such as coconut water and lemon juice.
After the adequacy of bowel preparation is deemed fit, the patients will be taken for
colonoscopic examination. A single blinded outcome assessment will be done by the
colonoscopist/endoscopist performing the procedure (adequacy of bowel preparation) and
the endoscopy nurse (tolerability and compliance).
Colonoscopy will be performed using standard video colonoscopes (Olympus, Tokyo, Japan)
between 11:00 AM and 1:00 PM without sedation. The colonoscopist / endoscopist will
assess the adequacy of bowel preparation using the Boston Bowel Preparation Scale (BBPS).
Excellent, good and poor bowel preparations will be defined by BBPS score of 9, 6 - 9 and
< 6, respectively. (12-14) Blood sampling will be done before bowel preparation and after
colonoscopy in all patients for measurement of baseline parameters, renal function status
(Serum creatinine, serum urea), serum electrolytess (serum sodium, serum potassium, serum
phosphate and serum calcium) and haematocrit.
Assessment of safety and tolerability will be performed using clinical examination and
symptom questionnaire. Cardiovascular and gastrointestinal (GI) symptoms will be
recorded. Cardiovascular symptoms such as dyspnea, palpitations, chest pain, will be
recorded and scored using the NYHA classification system for symptom severity. Clinical
examination will be carried out post-bowel preparation and post-procedure to assess for
signs of fluid overload, i.e. auscultation for crepitations and measurement of JVP. GI
symptoms such as nausea, abdominal pain, vomiting, dizziness, bloating, and headache will
be recorded and scored on a 4-point scale: 1 = none, 2 = mild, 3 = moderate, and 4 =
severe. The compliance of bowel preparation will be defined as "poor" for patients who
consume less than 75% of the PEG preparation.