A Comparison of 2 L of Polyethylene Glycol and 45 mL of Sodium Phosphate versus 4 L of Polyethylene Glycol for Bowel Cleansing: A Prospective Randomized Trial

BACKGROUND/AIMS: Polyethylene glycol (PEG)-based gut lavage solutions are safe and effective, but require the intake of large volumes of fluid. The use of 2 L PEG plus 45 mL sodium phosphate (PEG2 plus NaP) was compared with 4 L PEG (PEG4) for bowel cleansing before colonoscopy. METHODS: Patients were randomized to the PEG2 plus NaP group or PEG4 group between January 1, 2009 and March 31, 2010. One hundred and thirty patients were included in the PEG2 plus NaP group, and 141 patients in the PEG4 group. RESULTS: The qualities of the bowel preparation, based on the Ottawa scale were not significantly different between the groups (4.8±2.25 for the PEG2 plus NaP group vs. 5.11±2.26 for the PEG4). In addition, there were no significant differences in side effects. Laboratory findings after bowel preparation, including electrolyte, phosphorus and creatinine levels, were within the normal ranges in both groups. CONCLUSIONS: PEG2 plus NaP provides good cleansing that is similar to PEG4, but with a lower volume. However, because PEG2 plus NaP can cause serious side effects such as calcium deposition in the kidneys (i.e., nephrocalcinosis), this solution might be considered for the outpatients who cannot tolerate PEG4.