Rate of dislodgment of ureteral stents when using an extraction string after endoscopic urological surgery

Ureteral stents are manufactured with an extraction string tethered to the distal end, which facilitates removal after urological surgery. However, the string may allow for stent dislodgment. We report the stent dislodgment rate in a multi-institutional series.

We retrospectively reviewed the records of ureteroscopy cases at 3 academic endourology practices. Demographic and operative data were obtained as well as string use and stent dislodgment data. Categorical variables were assessed with the Fisher exact test and the Student t-test was used to assess continuous variables.

Of the 512 cases a string was used in 98 (19.1%) comprising 41 females (41.8%) and 57 males (58.2%). The stent was dislodged in 10 women and 3 men. No dislodgment occurred when a string was not used. When stratified by gender, 5.3% of men and 24.4% of women with a string experienced stent dislodgment (p = 0.013). Women were more than fourfold more likely to experience stent dislodgment than men (RR 4.6, 95% CI 1.36-15.8, p = 0.01).

Almost 15% of patients in whom a stent is placed with a string sustain stent dislodgment and most of these patients will be women. We recommend considering the risks of dislodgment in each patient who undergoes ureteroscopy with stent placement and considering string removal if the surgeon believes that dislodgment could result in adverse events such as severe colic or obstruction.