Nguyen DP et al, 2015: Optimization of extracorporeal shock wave lithotripsy delivery rates achieves excellent outcomes in ureteral stones. Results of a prospective, randomized trial.
Nguyen DP, Hnilicka S, Kiss B, Seiler R, Thalmann GN, Roth B.
Department of Urology, University of Bern, Bern, Switzerland.
Abstract
PURPOSE: Management of ureteral stones remains controversial. To determine whether optimizing extracorporeal shock wave lithotripsy (ESWL) delivery rates improves treatment of solitary ureteral stones, we compared outcomes of two SW delivery rates in a prospective, randomized trial.
MATERIALS AND METHODS: From July 2010 to October 2012, 254 consecutive patients were randomized to undergo ESWL at SW delivery rates of either 60 pulses (n=130) or 90 pulses (n=124) per min. The primary endpoint was stone-free rate at 3-month follow-up. Secondary endpoints included stone disintegration, treatment time, complications, and the rate of secondary treatments. Descriptive statistics were used to compare endpoints between the two groups. Adjusted odds ratios and 95% confidence intervals were calculated to assess predictors of success.
RESULTS: The stone-free rate at 3 months was significantly higher in patients who underwent ESWL at a SW delivery rate of 90 pulses per min than in those receiving 60 pulses (91% vs. 80%, p=0.01). Patients with proximal and mid-ureter stones, but not those with distal ureter stones, accounted for the observed difference (100% vs. 83%; p=0.005; 96% vs. 73%, p=0.03; and 81% vs. 80%, p=0.9, respectively). Treatment time, complications, and the rate of secondary treatments were comparable between the two groups. In multivariable analysis, SW delivery rate of 90 pulses per min, proximal stone location, stone density, stone size and the absence of an indwelling JJ stent were independent predictors of success.
CONCLUSIONS: Optimization of ESWL delivery rates can achieve excellent results for ureteral stones.
Embargo!!
J Urol. 2015 Feb 5. pii: S0022-5347(15)00235-9. doi: 10.1016/j.juro.2015.01.110. [Epub ahead of print]
Comments 1
READ IT!
What a relief to read this publication among all these retrospective studies literature which tries to sell causal trues by showing statistical relations.
Besides the design of the study there are a few other facts which contribute to the good success rate:
1. The authors are devoted to their lithotripter and they call it the “ “Rolls-Royce” among lithotripters”
2. “The Dornier HM-3 was operated by the same technician with more than 25 years of experience at the start of the study, under the supervision and guidance of a specially-trained resident and a senior staff member” This alone is a treatment quality booster.
3. “All ESWL treatments were given under anesthesia (general or regional) to eliminate pain as a limiting factor and to keep respiratory movements regular”
The authors conclude “The main limitation of our study is that all patients were treated with the modified Dornier HM-3. It is unknown, therefore, whether our results can be generalized to the current generation of electromagnetic or piezoelectric lithotripters. The optimal SW delivery rate may vary depending on the type of device”
This should stimulate others to repeat this study with the lithotripters they are using. If journal editors would only accept publications designed like the present one the urologists reading working load would be reduced to 90%.