Preventing retrograde stone displacement during pneumatic lithotripsy for ureteral calculi using lidocaine jelly.

Objectives: To assess the efficacy of lubricating jelly instillation proximal to the upper ureteral calculi during lithotripsy on the prevention of retrograde stone displacement and the stone-free rate.
Methods: Thirty-four patients with upper ureteral calculi of less than 2 cm were randomized into two groups: jelly instillation (n = 16) and controls (n = 18). Ureteroscopy was performed using a 9.8F semirigid ureteroscope. A 5F ureteral stent was advanced beyond the stone. Lidocaine jelly (2 mL) was instilled, and lithotripsy was done with a Swiss Lithoclast. A 5F ureteral catheter was left in place for 24 hours, and patients were followed up at 24 hours with radiography of the kidneys, ureters, and bladder and at 2 weeks with intravenous urography.
Results: Both groups were comparable in terms of mean age and stone size. Stone or stone fragment migration occurred in 12.4% of the treatment group and 44.4% of the controls, statistically significantly different (P = 0.046). The stone-free rate was 93.7% and 83.3% in the treatment and control groups, respectively. The rates did not improve after 2 weeks, and the difference was not statistically significant between the two groups (P = 0.384). The mean operative time was also comparable between the two groups.
Conclusions: Lidocaine jelly instillation proximal to the ureteral calculi during lithotripsy is an effective method to prevent retrograde stone displacement, but its effect on improving the stone-free rate was not significant in our study. Larger studies are needed to disclose more details about the efficacy of this method.