A Randomized Clinical Trial of Lidocaine Jelly for Prevention of Inadvertent Retrograde Stone Migration During Pneumatic Lithotripsy of Ureteral Stone

Purpose: We studied the efficacy of lidocaine jelly instillation proximal to the ureteral stone during intracorporeal lithotripsy using a semirigid ureteroscope for the prevention of retrograde migration and improvement in stone-free rate. Materials and Methods: From November 2006 to September 2007, 50 patients with 5 to 18 mm ureteral stones undergoing ureteroscopic removal using pneumatic lithotripsy were randomized into 2 groups. Group 1 (25 patients) had lidocaine jelly instilled proximal to the stone before and after fragmentation, and group 2 was the control group (25 patients). Ureteroscopy was performed using an 8 or 6.4Fr semirigid ureteroscope. A 5Fr ureteral stent was advanced beyond the stone. Lidocaine jelly (2 ml) was instilled and lithotripsy was performed with a Swiss LithoClast^™. A 5Fr ureteral catheter was left in place for 24 hours. Patients were followed at 24 hours with plain x-ray of the kidneys, ureters and bladder, and at 2 weeks with noncontrast enhanced computerized tomography of the kidneys, ureters and bladder. Results: The 2 groups were comparable with regard to age and stone size. Stone or stone fragment migration occurred in 4% and 28% of patients in groups 1 and 2, respectively, and this difference was statistically significant (p = 0.002). At 2 weeks followup with imaging the stone-free rate was 96% and 72% in groups 1 and 2, respectively, and this difference was also statistically significant (p = 0.045). Although the mean operative time was slightly longer in the treatment group (33.56 ± 13 vs 35.84 ± 12.5 minutes) the difference was not significant (p = 0.450). Conclusions: Lidocaine jelly instillation proximal to ureteral calculi during lithotripsy is an effective method of preventing retrograde stone displacement as well as significantly improving the stone-free rate.