Safety of the ureteral access sheath in unstented ureters

Abstract

Introduction and objective: With advances in technology in recent years, the indications for flexible ureterorenoscopy (fURS) for the treatment of upper urinary tract stones have expanded. To facilitate retrograde access to the kidney, extraction of fragments and reduction of intrarenal pressure during surgery, the ureteral access sheath (UAS) was introduced. The aim of the present study was to investigate the incidence of postoperative stricture after the use of UAS in unstented patients and the effectiveness and safety of different sizes of UAS. Material and methods: A retrospective study was performed, including 240 fURS procedures with the use of UAS, performed between January 2019 and April 2022. We excluded cases in which a previous intervention was performed, patients with a JJ stent, nephrostomy or impacted stones, patients who underwent radiation treatment, or had urinary tract malignancies. The postoperative stricture was considered the presence of hydronephrosis on ultrasound examination or on CT scan in the first and third months. A comparative analysis of the effectiveness and safety of using the 11/13 Fr UAS and the 12/14 Fr UAS was performed. Results: The cohort included 167 patients with a postoperative follow-up of 3 months. In 143 patients (85.7%) UAS 11/13 Fr was used, in 24 patients (14.3%) UAS 12/14 Fr. No postoperative stricture was found in any of the patients. There was no significant difference in efficacy after one procedure using UAS 11/13 versus UAS 12/14 (93.0% vs. 91.7%, p=0.684), despite the larger stone volume in UAS 12/14 (123.4±93.5 mm2 vs. 95.5±41.5, p=0.009). Mean operative time was significantly longer in UAS 11/13 (38.7±11.2 min vs 50.2±16.2 min; p=0.049). Larger UAS size was not associated with more complications compared to a smaller size, comparative safety analysis found no significant differences in the incidence of intra- and postoperative complications (0% vs. 0.7%, p=0.821 and 8.4% vs. 7.2% p=.705, respectively). Conclusions: The results of this study suggest that UAS use has no impact on the efficacy of fURS and is not associated with an increased rate of intra- and postoperative complications.