Autoaugmentation peritoneocystoplasty in a sheep model

OBJECTIVE: To report our experience with autoaugmentation peritoneocystoplasty (AAPC) in a sheep model, and to compare the results with autoaugmentation gastrocystoplasty (AAGC) in a sheep model and in paediatric patients. MATERIALS AND METHODS: Ten 6-month-old male lambs underwent bladder augmentation by detrusorotomy. A flap of parietal peritoneum, dissected from the anterior abdominal wall, was used to cover the bladder mucosa. The sheep were evaluated by urodynamics 6 months after surgery. Bladder compliance (bladder volume/intravesical pressure) was calculated for the bladder capacity at leakage. The urodynamic results were compared with age-matched control sheep and with 12 sheep that had undergone AAGC; the results were assessed using the Mann-Whitney U-test. RESULTS: In two of the 10 sheep, bladder volumes after AAPC increased by > 100%, although for the group, the mean (range) bladder volume after augmentation, at 159 (42-261) mL, was not significantly different from that before surgery (mean 143 mL). Bladder volumes after AAPC were not significantly different from those in the control sheep (mean 205 mL) but were significantly less than in the AAGC group (mean 317 mL; P < 0.05). Bladder compliance at leak capacity in the AAPC group (mean 5.4 mL/cmH2O) was also not significantly different from the controls (mean 9.1 mL/cmH2O), but was lower than the in the AAGC animals (median 14.6 mL/cmH2O; P < 0.05). CONCLUSIONS: AAPC in a sheep model does not result in a reliable increase in bladder volume or compliance. The volume and compliance are inferior to those found in bladders augmented by AAGC.