Increasing the size of ureteral access sheath during retrograde intrarenal surgery improves surgical efficiency without increasing complications.

PURPOSE: To directly compare intraoperative and post-operative outcomes and complications between three groups undergoing ureteroscopy: no ureteral access sheath, 12/14 Fr and larger 14/16 Fr ureteral access sheaths (UAS).

METHODS: We retrospectively reviewed demographic, pre-operative, intraoperative, and post-operative data of 257 patients who underwent ureteroscopy for nephrolithiasis by a single surgeon from January 2013 through July 2015. Patients were separated into three groups: no UAS, a 12/14 Fr UAS, or 14/16 Fr UAS. Outcomes included differences in stone-free rate, post-procedure-related events (PRE), ureteral injury rate (measured by early post-operative hydronephrosis), and post-operative complications.

RESULTS: A UAS was used in 65.4% (168/257) patients, with 73.8% (124/168) utilizing a 12/14 Fr UAS and 26.2% (44/168) utilizing a 14/16 Fr UAS. Those patients in whom a 14/16 Fr UAS was employed had greater stone burden compared to the 12/14 Fr UAS group (180.8 ± 18.0 vs. 104 ± 9.1 mm2 , p < 0.001). When comparing 12/14 Fr and 14/16 Fr ureteral access sheaths, there was no significant difference in ureteral injury rate, complications (10.5 vs. 11.4%, respectively; p = 0.87), or overall stone-free rate (78.1 vs. 81.3%, p = 0.70). The mean amount of stone burden treated per minute of operative time was more than 30% higher in the 14/16 Fr UAS group compared to 12/14 Fr UAS group (2.11 vs. 1.62 mm2 /min; p = 0.01).

CONCLUSION: The use of a 14/16 Fr UAS allows for similar stone-free rate and improved operative efficiency with no increased risk of ureteral injury or post-operative complications when compared to the 12/14 Fr UAS.