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.