Improving the view in the rectal clinic: a randomised control trial

Rigid sigmoidoscopy forms an integral part of the out-patient assessment of patients with colorectal symptoms. However, the value of this of this examination is often diminished by faecal loading of the rectum. This trial aimed to determine the ability of a single self-administered glycerine suppository to clear the rectum in preparation for rigid sigmoidoscopy, and considered patient acceptability of this practice.

Consecutive patients were randomly allocated to receive suppository or no suppository prior to out-patient rigid sigmoidoscopy. Assessment was made of patient compliance, the effectiveness of rectal examination, and the depth to which the sigmoidoscope was inserted.

131 patients were randomised into suppository (n = 66) or control groups (n = 65). The number of patients deemed to have good views of the rectum (> 75% of rectal mucosa seen) was significantly greater in suppository than control groups (79% versus 26.2%, P < 0.05 Chi square test), whilst that of poor examinations (< 50% of rectal mucosa seen) was significantly greater in control than suppository groups (44.6% versus 4%, P < 0.05). The depth of insertion of the sigmoidoscope was significantly greater in those receiving suppositories (54.5% versus 21.5% undergoing evaluation to 18 cm or more, P < 0.05). Compliance amongst those who received suppositories was high with only 3 of 53 (4.5%) patients in the suppository group evaluated by questionnaire reporting difficulty or concerns over their use.

Self-administered suppositories are acceptable to patients and significantly improve the efficiency of outpatient rigid sigmoidoscopy. Their usage should become routine.