Mechanical colon cleansing for screening colonoscopy: A randomized controlled trial

OBJECTIVE: Effective screening colonoscopy depends on the quality of colon preparation. This study aimed to compare pulsed irrigation evacuation (PIE), polyethylene glycol (PEG) and sodium phosphate colon preparations. METHODS: Outpatients at a VA hospital were randomized using sealed envelopes. Preparations consisted of polyethylene glycol 4L, Fleet sodium phosphate 90 mL with four to six glasses water twice daily and 296 mL of magnesium citrate in the evening with PIE prior to colonoscopy. Colon cleansing was assessed blindly using a five-point scale: 0 (very poor) to 4 (excellent). RESULTS: Altogether 391 patients participated in the study (129 in the PEG group, 127 in the sodium phosphate and 135 in the PIE group), with a mean age of 62 years, of whom 75% were men. PIE and sodium phosphate were superior to PEG: median cleansing scored 4 (excellent) versus 3 with PEG (P < 0.01). Inadequate preparations were more common with PEG than PIE (18% vs 5%) (P < 0.01). Side-effects included vomiting: 37% in the sodium phosphate group versus 5% in the PEG and 2% in the PIE groups (P < 0.01). The three preparations were judged intolerable in ≤ 5%. CONCLUSIONS: PIE and sodium phosphate are superior to PEG for colon preparations. PIE is the preferred preparation for those at high risk of unsatisfactory preparations or with unsatisfactory traditional preparations.