Cancellation rates and gas scores for air contrast barium enema immediately after 65-CM flexible sigmoidoscopy. A randomized clinical trial.

A randomized prospective study examined the impact of bowel gas introduced by 65-cm flexible sigmoidoscopy (FS) on the ability to perform air-contrast barium enema (ACBE) on the same day. Seventy-five patients at risk for colorectal cancer were randomly assigned to two groups. Of these, 28 patients in each group completed the protocol. The study group received flexible sigmoidoscopy and air-contrast barium enema on the same day, whereas the control group had their air-contrast barium enema on a different day. Bowel gas observed on an abdominal scout film prior to air-contrast barium enema was quantified on a scale of 1 (excessive gas) to 5 (no gas). The cancellation rate for the air-contrast barium enema was measured in each of the groups. The study group had significantly more bowel gas compared with the control group (p = 0.000003). The air-contrast barium enema cancellation rate was also higher in the study group (36%) than in the control group (14%) (p = 0.06). Greater than 60% of the study group patients were successfully examined. Same-day scheduling would reduce the number of bowel preparations required in the evaluation of patients at risk for colorectal cancer. Although retrospective studies have suggested no impact of same-day FS on ACBE quality, radiologists in this study canceled approximately one-third of scheduled patients due to perceived excessive bowel gas.