Identifying patients who are suitable for stentless ureteroscopy following treatment of urolithiasis.

PURPOSE: Foregoing ureteral stents following ureteroscopy for urinary calculi is an evolving practice. Randomized trials support stent omission in select cases though generalizability is unclear and criteria for stentless ureteroscopy are unknown. Therefore, we sought to identify significant clinical characteristics affecting postoperative morbidity in unstented patients to provide a context for future randomized trials.
MATERIALS AND METHODS: Of 837 ureteroscopic procedures for urolithiasis performed at our institution from January 1997 through January 2002 a ureteral stent was not placed in 226 (32%). Among these patients 47 had no stone at the time of the procedure leaving 219 (26%) who were treated for urinary calculus disease. Multivariate logistic regression was used to determine the association of 24 variables with postoperative morbidity.
RESULTS: Of the 219 patients treated with ureteroscopy 39 (18%) had a postoperative complication, which was obstructive in 26 (12%), infectious in 10 (5%), and related to patient co-morbidity in 3 (1%). Factors associated with postoperative morbidity included renal pelvic location (p = 0.02), lithotripsy (p = 0.03), bilateral procedure (p = 0.07), history of urolithiasis (p <0.0001), diabetes mellitus (p = 0.06), recent/recurrent infection (p <0.0001), operative time 45 minutes or greater (p = 0.07), operative time 45 minutes or greater plus lithotripsy (p = 0.0004), operative time 45 minutes or greater plus ureteral dilation (p = 0.07) and bilateral stentless procedure (p = 0.005).
CONCLUSIONS: Multiple patient and operative factors may predispose a patient to postoperative morbidity after a stentless procedure. Future trials should prospectively validate the role of these factors in either promoting (e.g., history of urolithiasis) or preventing (e.g., preoperative stent) a postoperative complication in the setting of stentless ureteroscopy.