Effect of extracorporeal shock wave lithotripsy on glomerular and tubular functions

Does Stepwise Voltage Ramping Protect the Kidney from Injury During Extracorporeal Shockwave Lithotripsy? Results of a Prospective Randomized Trial

BACKGROUND

Renal damage is more frequent with new-generation lithotripters. However, animal studies suggest that voltage ramping minimizes the risk of complications following extracorporeal shock wave lithotripsy (SWL). In the clinical setting, the optimal voltage strategy remains unclear.

OBJECTIVE

To evaluate whether stepwise voltage ramping can protect the kidney from damage during SWL.

DESIGN, SETTING, AND PARTICIPANTS

A total of 418 patients with solitary or multiple unilateral kidney stones were randomized to receive SWL using a Modulith SLX-F2 lithotripter with either stepwise voltage ramping (n=213) or a fixed maximal voltage (n=205).

INTERVENTION

SWL.

OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcome was sonographic evidence of renal hematomas. Secondary outcomes included levels of urinary markers of renal damage, stone disintegration, stone-free rate, and rates of secondary interventions within 3 mo of SWL. Descriptive statistics were used to compare clinical outcomes between the two groups. A logistic regression model was generated to assess predictors of hematomas.

RESULTS AND LIMITATIONS

Significantly fewer hematomas occurred in the ramping group(12/213, 5.6%) than in the fixed group (27/205, 13%; p=0.008). There was some evidence that the fixed group had higher urinary β2-microglobulin levels after SWL compared to the ramping group (p=0.06). Urinary microalbumin levels, stone disintegration, stone-free rate, and rates of secondary interventions did not significantly differ between the groups. The logistic regression model showed a significantly higher risk of renal hematomas in older patients (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.00-1.05; p=0.04). Stepwise voltage ramping was associated with a lower risk of hematomas (OR 0.39, 95% CI 0.19-0.80; p=0.01). The study was limited by the use of ultrasound to detect hematomas.

CONCLUSIONS

In this prospective randomized study, stepwise voltage ramping during SWL was associated with a lower risk of renal damage compared to a fixed maximal voltage without compromising treatment effectiveness.

PATIENT SUMMARY

Lithotripsy is a noninvasive technique for urinary stone disintegration using ultrasonic energy. In this study, two voltage strategies are compared. The results show that a progressive increase in voltage during lithotripsy decreases the risk of renal hematomas while maintaining excellent outcomes.

TRIAL REGISTRATION

ISRCTN95762080.

The protective role of coenzyme Q10 in renal injury associated with extracorporeal shockwave lithotripsy: a randomised, placebo-controlled clinical trial

OBJECTIVE

To determine the efficacy of coenzyme Q10 (CoQ10) in preventing renal injury in patients with lithiasis undergoing extracorporeal shockwave lithotripsy (ESWL).

PATIENTS AND METHODS

Prospective, randomised, double-blind, placebo-controlled clinical trial of 100 patients with renal lithiasis who were treated with ESWL. The patients were distributed randomly into two groups receiving either placebo or CoQ10 (200 mg/day), a powerful antioxidant with vasoactive properties, orally administered during the week before ESWL and for 1 week after. Renal dysfunction markers, vasoactive hormones, oxidative stress, plasma levels of several interleukins and vascular resistance index (VRI) using Doppler ultrasound were evaluated the week before ESWL, 2 h before ESWL and at 2 h, 24 h and 7 days after ESWL.

RESULTS

There was a significant increase in glomerular filtration (P = 0.013), as well as a decrease in the albumin/creatinine ratio and the β2 -microglobulin level (P = 0.02) after 1 week of treatment in the CoQ10 group. These changes were maintained at the follow-up after ESWL. The administration of CoQ10 was associated with improvement in vasoactive hormone parameters, VRI and interleukin levels. These improvements were maintained until the end of the follow-up period. However, the administration of CoQ10 was not associated with significant changes in the oxidative stress parameters.

CONCLUSION

Our results indicate that CoQ10 administration improves renal function and vasoactive and inflammation parameter values, allowing for preconditioning before the tissue insult caused by ESWL.

Effects of repeated extracorporeal shock wave in urinary biochemical markers of rats

PURPOSE

To access the effect of repeated extracorporeal shock wave (ESW) on urinary biochemical markers

METHODS

20 rats were assigned for ESW (Direx Tripter X1(R) - 14 KV) to one of two groups: G1 (n=10) one ESW; G2 (n=10) two ESWs within a 14-day interval. Within the twenty-four hour period before and after the application of shock waves, the animals were placed in metabolic cages for 24 hour urine collection. The ph, creatinine, sodium, potassium, chlorides, calcium, magnesium, phosphorus, oxalates, alkaline phosphatase and citrates were measured. Twenty-four hours after the material was collected for urinary determination, the animals underwent nephrectomy of the kidney submitted to the ESW applications and were, then, sacrificed. The kidneys were processed for histopathological examination.

RESULTS

Small variations in the biochemical markers were found in both groups, with no significant differences between the values obtained either prior to or following the ESW applications, except for citrate and alkaline phosphatase. Citraturia decreased significantly in group 2, following the second ESWL application (24.8 +/- 3.0 mg/day after the first ESWL vs. 15.3 +/- 2.2 mg/day after the second ESWL; p < 0.05). Alkaline phosphatase increased significantly following ESWL in group I (0.57 +/- 0.02 vs. 0.79 +/- 0.04 micromol/mg creatinine; p < 0.01) and also in group 2 (0.69 +/- 0.05 vs. 0.83 +/- 0.03 micromol/mg creatinine; p < 0.05). Glomerular, interstitial and sub-capsular hemorrhage with perivascular edema was found in the animals in both groups studied.

CONCLUSIONS

A significant increase in urinary alkaline phosphatase was found in both groups studied, suggesting a proximal tubule lesion. In the group of rats undergoing more than one ESWL application, a smaller urinary citrate excretion was noticed, which may be a factor contributing for the formation of new calculi.

[A comparative study of the renal damage produced after the extracorporeal shock wave lithotripsy according to the lithiasis location]

INTRODUCTION

The Extracorporeal shock waves lithotripsy (ESWL) is fundamental in the treatment of lithiasis. However, there are evidences that it can produce renal damage. The objective of our study is to determine the degree of affectation of the glomerular and tubular function after ESWL, and the influence of the lithiasis location on the type of renal damage.

MATERIAL AND METHODS

A prospective longitudinal study was carried out in 14 patients with normal renal function subjected to ESWL. We determined the basal level, and the levels at the 24 hours, at the 4th and the 10th day post ESWL of: microalbuminuria (MA) (that values the glomerular function), and N-acetyl glucosamide (NAG) and alanine aminopeptidase (AAP), (that value the tubular function).

RESULTS

The basal levels of of MA, NAG and AAP didn't show significant differences in connection with the localization of the stones. A significant increase was observed of the three parameters only 24 hours post ESWL. No significant differences were observed between the variation of the microalbuminuria levels, AAP and NAG and the treatment in relation to the localization of the stones.

CONCLUSIONS

It exists a glomerular and tubular damage after ESWL. This damage is not related with the pelvic or calicial location of the stones. In patient with previous normal renal function, the renal damage recovers at the 4th day post ESWL.

Estimating the effectiveness of various methods of evacuation of kidney stones, on the basis of data obtained on percentage of "stone free" and recurrent stone formation

Using the materials of more than 200 scientific papers of recent years in this review it has been carried out analysis of the effectiveness and also discussed the merits and demerits of various methods of treatment of urinary stone diseases (USD). With this purpose, for the first time it has been carried out analysis of treatment quality of USD using more important quantitative parameters of treatment efficacy: 1--percentage of "stone free"; 2--percentage of recurrent stone formation. It has been emphasized on the higher effectiveness of treatment in combination of the method of ESWL with the methods of ascending litholysis. It was shown that in order to solve problems such as etiology and pathogenesis of the disease, elaboration of quantitative risk factors of the disease, and search for effective measures on pro- and metaphylaxis of USD, and also elaboration of various (including therapeutics) medium and methods for complete and rapid evacuation of stones, it is needed to carry out intensively fundamental and applied researches in the field of urinary stone diseases.