Introduction & Objective :
Primary ureteroscopy (URS) is a well-established and common treatment for urolithiasis. Occasionally, primary URS is unable to be performed. In these cases, a ureteral stent is often placed and intervention is attempted at a later date.
Previous failure rates for primary URS have been quoted at 7.7-16%. Young females and proximal stones have been associated with a higher risk of failure, although data is limited. The objective of this study was to confirm these prior findings, as well as identify other characteristics associated with primary URS failure.
A retrospective chart review of consecutively scheduled URS for urolithiasis from 11/1/17-11/10/17 and 12/1/17-12/31/17 was performed. Data was obtained from a large, multi-physician urology practice. 190 renal units (RU) were identified. Of these, 99 were pre-stented and therefore excluded from analysis. Four non-stented RUs were excluded, as definitive therapy had not yet occurred at time of study end-date. Following this, 84 RUs (81 patients) were identified for analysis.
Demographics, history of urolithiasis, stone location, emergency department (ED) visits, and narcotic prescription habits were analyzed using Fisher’s exact test and unpaired T-test. Failure was defined as the inability or unwillingness to access the ureter to perform stone manipulation.
Results : Overall failure rate was 7.1% (7 units). Five failures were due to narrow ureters and one was due to concern for infection. Average time from ureteral stent to definitive treatment was 21.7 days. Male sex was significantly associated with failure (Table 1).
Primary failed URS has both patient and system-wide implications. It subjects patients to increased general anesthesia and urinary tract manipulation, and results in unplanned loss of OR time. If patients at risk could be identified, interventions to reduce this event could be performed.
Overall failure rate was 7.1% in this study, which is similar to previous reports. In contrast to the literature, we found male sex was significantly associated with primary URS failure. There was no difference in age, stone location, history of stones, previous interventions, post-op ED visits, or number of narcotics prescribed.