Impact of forced diuresis on retropulsion of disintegrated ureteral calculi during semi-rigid ureteroscopy: a...

The objective of this study is to assess the safety and efficacy of forced diuresis as an antiretropulsion strategy during the pneumatic disintegration of solitary lower ureteric stones with semi-rigid ureteroscopy (URS). A prospective randomized double-blind study was carried out from March 2019 to June 2021 for patients presented with unilateral solitary radiopaque lower ureteric stones ≤ 20 mm. Patients were randomized for URS into two groups, according to the use of forced diuresis using furosemide 1 mg/kg (GII) or not (GI). Perioperative parameters were compared between both groups, including retropulsion rate, stone-free rate (SFR), and need for auxiliary procedures and complications. A total of 148 patients were included; 72 (48.6%) in GI and 76 in the GII (51.4%), with respective stone size of 11.8 ± 2.6 vs.12.1 ± 2.4 mm. Both groups were comparable in demographic and baseline data, with a mean age of 47 ± 16 and 50 ± 14 years for GI and GII, respectively. GII had a significantly shorter disintegration time (10.5 ± 1.3 vs. 4.2 ± 2.1 min, p < 0.001), shorter operative time (33.1 ± 10.1 vs. 40.8 ± 9.1 min, p < 0.001), lower stone fragments migration rate during disintegration (6.5% vs. 18.1%, p = 0.04), lower retropulsion rate (1.3% vs. 11%, p = 0.02), higher SFR (96.1% vs. 86.1%, p = 0.04), and lower auxiliary procedures (3.9% vs. 13.8%, p = 0.03). Intraoperative and 6-h postoperative changes in heart rate and mean systolic blood pressure were comparable between both groups. Ephedrine injection (6-18 mg) was needed in significantly more GII patients (39.5% vs. 20.8%, p ≤ 0.01). It seems that forced diuresis during pneumatic lithotripsy of the lower ureteric stones is a safe and effective antiretropulsion technique. This would expand the alternative options to the antiretropulsion strategy, especially in centers where the laser and flexible ureteroscopes are not available.