Influence of suture diameter on microsurgical ureterorrhaphy in rabbits: an experimental study

Abstract

Background Ureteral obstruction is a common indication for surgical intervention, due to the small size of the ureter, specialized instrumentation is required such as operating microscope for intraoperative magnification and microsutures. The aim of this study is to evaluate and compare 3 sizes of nylon 6 − 0,8 − 0,10 − 0 for ureterorrhaphy in the ureter of rabbits, using microsurgical technique. Results A total of fifteen male, adults, New Zealand rabbits were divided in three groups: all groups were submitted ureterotomy. A 2 mm longitudinal incision was made in the medial portion of the right ureter, followed by a partial perforating simple interrupted 6 − 0, 8 − 0 and 10 − 0 sutures in each group. During the experiment ultrasound evaluations were performed to assess the kidney length and width, the presence of ureteral calculi, the renal pelvic dilation, the ureter diameter and the presence of free liquid in the abdominal cavity. At the end of the experiment all kidneys and ureters were submitted to macroscopic and histopathological evaluations. In the first ultrasound assessment, all groups had an acute increase in renal length (p < 0.048). The group with 8 − 0 suture showed a difference in ureteral diameter on the 5th day (p < 0.01) and all groups showed a reduction in diameter on the 30th day. The group with 6 − 0 suture showed a high mortality rate during the experimental period and the histopathological evaluation exhibited areas of necrosis. According to the ultrasound evaluation caliber 10 − 0 achieved better results in, macroscopic and microscopic evaluations. The finer suture diameters had better outcomes according to the ureteral inflammation scores. Conclusions The use of 10 − 0 suture resulted in lower rates of ureteral inflammation, renal changes and postoperative complications when compared to two other sizes of the same material.