Paper of the Month for May is a a single centre retrospective study looking at the use of cystogram following segmental bowel resection in patients with enterovesical fistula

Selective use of cystogram following segmental bowel resection in patients with enterovesical fistula.
de Groof et al. Colorectal disease 2019 [epub ahead of print]

What is known about this subject?

Enterovesical fistula is not infrequently seen, and typically occurs with complicated diverticular disease, or sometimes Crohn’s disease. Management is typically resection of bowel, bladder closure and urinary drainage for 10-14 days, often followed by a check cystogram. This practice seems to be one which has been handed down between surgeons, rather than truly evidence driven.

What this study adds?

Design: This is a single centre retrospective study undertaken in a single Dutch teaching hospital over a 21 year period.

Primary endpoints: The primary endpoint is bladder leakage, assessed clinically or with check cystogram.

Secondary endpoints: Recurrence of fistula, surgical complications, and death were reported as secondary outcomes.

Results: The study identified 46 patients in this study period. All underwent double layered closure of the bladder +/- omental flap. A check cystogram was performed for 26 patients at a median of 10 days post op (14 of these were performed before day 10). Bladder drainage was continued for a median of 11 days post surgery. Just 3 patients had a leak detected on cystogram, which was typically performed before day 10. One patient had a persistent leak on a second cystogram but had their catheter removed anyway with no reported sequelae. There was one recurrent fistula, which was ultimately found to be related to a bladder cancer.

Implications for colorectal practice?

Caution should be applied to interpretation of this study; it is small and retrospective. Nevertheless, it suggests that in this setting, check cystogram may not be required unless the patient shows signs of leakage before day 10 post op. Even where a leak is discovered, it is possible this may not mandate continued urinary drainage. I suspect clinicians would not be keen to move away from the safe conservative approach to bladder drainage, it might suggest a cystogram is not mandatory in all cases. A larger study is required to identify those at highest risk of ongoing leakage in order to limit additional radiation to this group.