# Conversion of Barnett continent reservoir to Kock reservoir: A 30-year retrospective study on surgical outcomes and long-term follow-up

## TL;DR

This 30-year study shows that converting a Barnett pouch to a Kock pouch improves long-term success and reduces failure in patients needing continent ileostomies.

## Contribution

Demonstrates the safety and effectiveness of converting Barnett to Kock pouches for improved long-term outcomes.

## Key findings

- Conversion to Kock pouch resulted in higher pouch salvage (81.3%) compared to non-conversion (35.7%).
- 60% of conversion group patients retained continent pouches after long-term follow-up.
- Conversion reduced failure rates and offered a viable alternative to permanent ileostomy.

## Abstract

The Barnett continent reservoir has long been used as a surgical option for patients requiring continent ileostomies, but complications such as valve leakage, obstruction, and pouch failure often necessitate revisions. Conversion to a Kock (K) pouch offers an alternative with potentially improved outcomes. This study evaluated the safety (postoperative complications), feasibility (technical completion of conversion), and effectiveness (long-term pouch salvage) of conversion.

We conducted a retrospective cohort study of patients who underwent Barnett-to-K-pouch conversion (conversion group) or remained with a Barnett pouch (non-conversion group) between 1991 and April 2024. The conversion technique included disconnection of the afferent limb, preservation and 180° rotation of the reservoir, resection of the collar valve, creation of a stapled nipple valve, and pouch–neo-afferent limb anastomosis. Demographics, surgical history, and long-term follow-up were collected. Pouch salvage was defined as retention of a functional continent pouch; failure was defined as excision with permanent ileostomy.

Out of 30 patients with Barnett pouch patients included, 16 underwent conversion and 14 did not. Median age was 51.5 versus 60.5 years, and median body mass index (BMI) was 24.7 versus 22.3 kg/m2 in conversion versus non-conversion groups, respectively. Ulcerative colitis was the primary indication (62.6% versus 78.8%). Leading revision causes were valve slippage (50% versus 35.7%) and fistula (18.7% versus 28.6%). Pouch salvage was higher with conversion (81.3%, 95% confidence interval [CI] 54–96%) versus non-conversion (35.7%, 95% CI 13–65%; p = 0.03). Long-term follow-up (median: 159.5 versus 301.6 months,) showed that 60% of all patients in conversion group retained continent pouches, while the remaining experienced pouch excision, indicating an overall failure rate of 40%.

Conversion of Barnett to K-pouch improves pouch salvage and reduces failure. While technically complex, the procedure can be safely offered to motivated patients seeking to avoid permanent ileostomy.