Understanding failures in getting it up: The prevalence and predictors of failed ureteral access in ureteroscopy

Abstract

Introduction
 Failed Access ureteroscopy (FA) describes the inability to gain adequate access to a stone to allow for treatment. The purpose of this study was to identify the prevalence of, and factors predicting FA in patients presenting with renal and ureteral stones.
 Methods:
 We performed a retrospective review of all uretersocopies for ureteral stones performed by three endourologists over a six month period. All patients who underwent URS for the purpose of stone treatment were included. Patients were excluded if they underwent ureteroscopy for non-stone diagnosis or treatment. FA was investigated in relation to demographics, medical history, stone specific characteristics, procedure specific characteristics etc. Statistical analysis consisted of descriptive statistics as well as chi-square and t-test analysis using SPSS statistical software version 23.0.
 Results:
 188 cases were reviewed, with 8% of patients experiencing FA. Patient age, gender, BMI, ASA score, emergency cases, previous stone treatment, use of CT imaging, presence of hydronephrosis, and surgeon did not differ significantly between FA and successful access (SA) groups. Stone size (9.88±5.8 vs 8.76±4.3mm; p=0.361) was also not significantly different. However, a significant difference was noted in time from first diagnosis to ureteroscopy (128 vs 65 days; p=0.044) and in stone location 62.5% vs 22.0% proximal ureter; p=0.043; OR=4.77 (1.05-21.64)
 Conclusions:
 Proximal ureteric stones were more likely to result in failed access ureteroscopy, and FA procedures were more likely to be preceded by extended time from first diagnosis to ureteroscopy. Further investigation is necessary, and all endourology centres should track their own personal outcome data in order to allow for more meaningful analysis to be performed to improve patient outcomes.

Ureteral Stent Placement Prior to Definitive Stone Treatment Is Associated With Higher Postoperative Emergency Department Visits and Opioid Prescriptions for Youth Having Ureteroscopy or Shock Wave Lithotripsy

“…Pre-stenting due to failure to access the ureter during URS in adults has been reported at 8-10%. 16,17 Although the European Society for Pediatric Urology guidelines on pediatric stone disease do not specifically recommend the use of ureteral stents, they note the need for pre-stenting for pediatric URS. Additionally, the European guidelines comment on a potential increase in complications in unstented SWL patients.…”

Success rate of repeat flexible ureteroscopy following previous failed access: An analysis of stent duration

“…In an internal review, we determined our failed access rate to be 8% of all ureteroscopy patients. 1 When access fails, the default decision is to place a ureteric stent and proceed with an interval or salvage secondary procedure. Most of the evidence on this is extrapolated from studies on the use of pre-stenting.…”

“…Approximately 8% of patients undergoing therapeutic or diagnostic ureteroscopy (URS) at our centre will have their procedure aborted due to an inhospitable ureter in what has been deemed "failed access." 1 Difficult access may be attributed to several processes including spasm, stenosis, stricture and tortuosity. For failed access, the traditional approach at our centre has been to place a ureteric stent and proceed with an interval procedure in 2 or more weeks.…”

Development and validation of a predictive model for failure of ureteral access sheath placement in patients with ureteral calculi

“…It is therefore necessary to identify the preoperative factors associated with failure of scentless rst-time UAS treatment. Although previous studies have identi ed one or more clinical factors to predict the outcome of UAS placement, joint analyses incorporating multiple clinical factors into multivariate predictive models have not been performed [9][10][11][12][13][14][15][16][17].…”