Comparative trial assessing suture techniques and types of urinary catheters in vesicourethral anastomotic tensile strength in a porcine model

Abstract

PURPOSE: Vesicourethal anastomosis (VUA) during radical prostatectomy can be achieved using various suture plication techniques. Traditionally, an indwelling urinary catheter remains in-situ to facilitate the healing process of the reconstructed VUA. Compromise or rupture of this anastomosis may lead to acute urinary leak and subsequent urinoma or stricture formation. This ex-vivo porcine model aims to evaluate VUA tensile strength using different suture techniques and catheter types. METHODS: Male porcine bladders were obtained and prostatectomy was performed. The specimens were randomized and VUA were created using 3-point interrupted, 6-point interrupted or 6 point continuous 3-0 monocryl suture. 20Fr catheters were utilized, specifically varying manufacturers (A and B) and catheter balloon shapes (round versus oval). The VUA model was placed within a reproducible pulley system and graduated weights were applied until failure of the catheter balloon or the model VUA. Model failure was defined as either 'VUA rupture', 'Catheter passage through VUA' or 'catheter failure'. RESULTS: Twenty consecutive porcine bladders were prepared, tested and utilized for analysis. VUA reconstructed with 3-point fixation was more likely to suffer VUA rupture (p=0.025) compared to 6-point interrupted or 6-point continuous VUA. Higher tensile pressure causing catheter balloon rupture (p=0.009) was observed for Manufacturer A. Catheters with oval-balloon shape were more likely to dislodge past the VUA without disruption of the anastomosis (p=0.002). CONCLUSIONS: During prostatectomy, anastomotic technique and catheter selection can significantly alter the tensile properties of the VUA. Further research is required to validate our findings in clinical models.