CLEANSING ABILITY AND TOLERANCE OF 3 BOWEL PREPARATIONS FOR COLONOSCOPY

PURPOSE: This study was undertaken to determine whether different regi mens using sodium phosphate (NaPh) solutions resulted in better bowel cleansing than polyethylene glycol-salt (PEG) solutions and, if so, wh y. Side-effects and patient acceptability of the different regimens we re also investigated. METHODS: A total of 486 patients requiring colon oscopy were randomly assigned to one of three preparations in a single -blind prospective study. The preparations were as follows: Group A, 3 liters of PEG solution taken at 2 p.m. the day before examination; Gr oup B, 45 ml of NaPh solutions taken at 7 a.m. and 7 p.m. the day befo re examination; or Group C, 45 ml of NaPh taken at 6 p.m. the day befo re and at 6 a.m. on the morning of, examination. Cleanliness of the bo wel was assessed blindly, and patients were questioned about side-effe cts and preferences for NaPh vs. PEG. RESULTS: Numbers, ages, and gend er distribution of patients in the three groups did not differ signifi cantly from each other. Cleanliness scores for the three groups were 3 .34 +/- 0.97, 3.22 +/- 0.85, and 4.11 +/- 0.67 (Group C vs. Groups A a nd B, P < 0.0005; Group A vs. Group B, P > 0.30). Predominance of mate rial in the right side of the colon was found in 13.7, 29.8, and 4.2 p ercent of Groups A, B, and C, respectively. In the three groups, nause a alone occurred in 3.8, 13.7, and 16.3 percent of patients; vomiting occurred in 0.6, 7.4, and 5.4 percent of patients; and dryness/thirst occurred in 1.9, 17.4, and 20.4 percent of patients, respectively. A t otal of 80.6 and 82.6 percent of those in Groups B and C who had previ ously had PEG expressed a preference for taking NaPh (P < 0.001). CONC LUSIONS: The regimen of Group C is significantly better than the regim ens of Groups A or B in bowel cleansing. Regimens of Groups A and B di d not differ in efficacy of cleansing. It is the timing of taking NaPh in the regimen of Group C rather than its composition that is respons ible for its superior cleansing ability compared with PEG. Overnight d eposition of small intestinal material in the right colon is partly re sponsible for the inferior cleansing ability of regimens that involve taking the solution on the day before colonoscopy. Despite a higher in cidence of minor side-effects from NaPh than from PEG, a significantly higher proportion of patients preferred NaPh.