Currently available preparations for colonoscopy have low tolerability and may cause fluid and electrolyte shifts. An alternative method of bowel cleansing is required.
Preparation of the gut using oral nutritional supplements (ONS) and rectal enema was tested as an alternative method of bowel cleansing. During 2008-2012, patients were randomized to oral nutritional supplements (n = 27) for 5 days and rectal enema or polyethylene glycol (PEG) (n = 23) prior to colonoscopy. Blinded endoscopists rated the degree of bowel cleansing according to the Ottawa bowel preparation scale (OBS) (primary outcome). Tolerability of either preparation was also assessed (ClinicalTrials.gov. Identifier no: NCT00123456).
Due to a high rate of bowel cleansing failure among patients receiving ONS, the study was interrupted prematurely. Colonoscopies were incomplete due to stools in 6 of 27 patients in the ONS group compared to 1 of 23 in the PEG group (ns). The mean total OBS were 8.3 ± 3.3 and 5.3 ± 2.8, respectively (p = 0.002). Four patients (15%) in the ONS group and eight patients (35%) receiving PEG had an OBS score =4 (good preparation) (ns). ONS was better tolerated than PEG with more patients reporting acceptable taste (27 of 27 [100%] vs. 15 of 23 [65%], p = 0.001), and fewer reporting difficulties with the intake (0 of 27 [0%] vs. 10 of 23 [43%], p