A trial to assess the effectiveness of bowel preparation prior to intravenous urography

A randomized prospective trial was undertaken to compare the relative effectiveness of two commonly used bowel preparations (senna tablets and sodium picosulphate powder) administered to patients before they underwent out-patient intravenous urography. Their 'control' films were compared with plain 'kidneys, ureters, and bladder' (KUB) radiographs of patients who had had no bowel preparation. The results show no significant difference in the degree of faecal shadowing between those receiving a bowel preparation and the unprepared patients. Nor is there any difference between the two laxatives. We conclude that the routine administration of a bowel preparation is unlikely to improve the diagnostic quality of out-patient intravenous urograms. In addition, 40% of the urogram patients found the effects of the laxatives to be unpleasant or very unpleasant.