Emergency extracorporeal shockwave lithotripsy (eSWL) as opposed to delayed SWL (dSWL) for the treatment of acute renal colic due to obstructive ureteral stone: a prospective randomized trial

BACKGROUND: To assess the efficacy of emergency extracorporeal shockwave lithotripsy (eSWL) as first-line treatment in patients with acute colic due to obstructive ureteral stone. METHODS: 74 patients were randomized to emergency SWL within 12 hours (eSWL group) and deferred SWL later than 3 days (dSWL group). Follow-up included ultrasound, KUB (Kidney-Ureter-Bladder) radiography and CT (computed tomography) scan at 24 hours, 7 days, 1 and 3 months from the treatment. When necessary, repeated SWL (re-SWL) or ureteroscopy (auxiliary-URS) was performed. Preoperative and postoperative data were compared and stone free rates (SFR) and efficiency quotients (EQ) were evaluated. Analyses were performed using SAS software. RESULTS: Complete data of 70 patients were collected. 36 underwent eSWL and 34 dSWL. The mean patient age was 48.7. Mean stone size was 9.8 mm (CI 95%, 8.9-10.8). 25 (35.7%) were proximal and 45 (64.3%) distal. Mean SWL energy was 19.2 kV (CI 95%, 18.5-19.9) and mean number of shocks was 2657 (CI 95%, 2513-2802). eSWL patients needs less auxiliary-URS than dSWL patients (13.9% vs 44.1%, p=0.039) and less re-SWL sessions (8.3% vs 32.4%, p=0.093). SFR at 24 hours was 52.8% and 11.8% (p<0.001) and the EQ at 3 months was 79.1% and 57.5% in the eSWL and dSWL group respectively. Patients from the dSWL group spent more time in the hospital (2.21 vs 1.36 days, p=0.046) and complication rates between the two groups were similar. CONCLUSIONS: eSWL is a safe procedure and delivers high SFR even within 24 hours especially for <10mm stones. It is able to reduce the number of auxiliary procedures and hospitalization.