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2 L versus 4 L of PEG3350 + electrolytes for outpatient colonic preparation: a randomized, controlled trial
Mayur Brahmania1, George Ou1, Brian Bressler1
1Division of Gastroenterology, Department of Medicine, St. Paul's Hospital, University of British Columbia, Vancouver, British Columbia, Canada.
Background:
Low-volume bowel preparations are ideal to ensure patient compliance, thus enabling high-quality examinations to be achieved.
Objectives:
To examine the bowel-cleansing efficacy and patient tolerability of split-dose 2 L PEG3350 + electrolytes (PEG3350e) with 15 mg bisacodyl versus split-dose 4 L PEG3350e.
Design:
Single-blinded, noninferiority, randomized, controlled trial.
Setting:
Single site, university-affiliated tertiary care center.
Patients:
A total of 325 consecutive patients undergoing elective outpatient colonoscopy.
Intervention:
2 L of PEG3350e with 15 mg bisacodyl versus 4 L of PEG3350e, both given in a split-dose fashion.
Main Outcome Measurements:
Efficacy and tolerability of a split dose of 2 L of PEG3350e with 15 mg bisacodyl. Efficacy was assessed by using the Boston Bowel Preparation Scale and Ottawa Bowel Preparation Scale. Patient satisfaction and tolerability were assessed by using a short survey.
Results:
A total of 325 patients were included in the intention-to-treat analysis (51% male) with a mean ± standard deviation age of 56 ± 11.2 years. No statistically significant difference in cleanliness was found by using the Boston Bowel Preparation Scale (intention-to-treat, P = .381; per-protocol, P = .387) and the Ottawa Bowel Preparation Scale (intention-to-treat, P = .285; per-protocol, P = .334). Participants receiving 2 L of PEG3350e found the preparation easy to consume and were willing to repeat the procedure more often than the 4-L group (P < .001).
Limitations:
Single-center study looking at outpatient colonoscopies; unable to comment on adenoma detection rate.
Conclusions:
Bowel-cleansing efficacy was similar in both the 2-L and 4-L PEG3350e groups; however, patient tolerability and willingness to repeat preparation were statistically greater with the 2 L of PEG3350e with 15 mg bisacodyl regimen.
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