Extracorporeal shockwave lithotripsy in patients treated with antithrombotic agents

Risk factors of hematoma after SWL for renal calculi: analysis from RCTs and a literature review

OBJECTIVE

To identify risk factors of perinephric hematoma following extracorporeal shockwave lithotripsy (SWL) for renal calculi through combined analysis of two randomized controlled trials.

PATIENTS AND METHODS

This post-hoc analysis included adult patients with solitary renal calculi ranging from 5 to 15 mm, treated with SWL between 2016 and 2022. All patients received cross-sectional imaging (either non-contrast computer tomography scan or magnetic resonance imaging) two days post-SWL to assess the presence and severity of perinephric hematoma.

RESULTS

Among 573 patients analyzed, 173 (30.9%) developed perinephric hematoma by Day 2 post-SWL. Multivariate logistic regression identified higher total energy delivered (odds ratio [OR] = 1.533, p = 0.003), higher mean stone density (OR = 2.603, p = 0.01), higher maximal stone density (OR = 3.578, p = 0.03), and lower pole stone location (OR = 1.545, p = 0.029) were risk factors for the development of hematoma. Conversely, the stepwise ramping protocol was a protective factor for hematoma formation. (OR = 0.572, p = 0.042).

CONCLUSIONS

This study elucidates key factors influencing the risk of perinephric hematoma post-SWL, highlighting the importance of procedural adjustments such as the stepwise ramping protocol to reduce complications. These insights call for targeted patient and treatment strategy optimization to enhance SWL safety and efficacy.

How can and should we optimize extracorporeal shockwave lithotripsy?

It is well recognized that the popularity of extracorporeal shock wave lithotripsy (SWL), despite its non-invasive character, has decreased during recent years. This is partly explained by the technological achievements in endoscopy and urologists’ enthusiasm for such procedures. Another explanation is that many urologists have been insufficiently successful with SWL. The latter effect might to some extent be a result of the performance of the lithotripter used, but in too many cases, it is evident that the principles of how shock wave lithotripsy should be carried out are poorly applied. The purpose of this article is to emphasize some important aspects on how SWL best should be used. Based on decades of experience, it stands to reason that success with SWL does not come automatically and attention has to be paid to all details of this technique.

A review study to evaluate holmium:YAG laser lithotripsy with flexible ureteroscopy in patients on ongoing oral anticoagulant therapy

The objective of this study was to evaluate the safety and efficacy of flexible ureteroscopy (FURS) and holmium:YAG laser lithotripsy for the treatment of upper urinary tract stones in patients on active oral anticoagulants. The records of 1081 patients who underwent flexible ureteroscopic holmium:YAG (Ho:YAG) laser lithotripsy for upper ureteral and renal calculi from 1999 to 2015 were retrospectively reviewed. A total of 84 patients on continuous oral anticoagulation or antiplatelet therapy (warfarin, aspirin, or clopidogrel) were identified. Of these patients, 40 were on warfarin, 25 on aspirin, 11 on clopidogrel, and 8 on both aspirin and clopidogrel. The drugs were not discontinued. The baseline characteristics, indications for anticoagulation therapy, perioperative data, stone-free rate, and complications were documented. Evaluation of outcomes was assessed at 1-, 3-, and 6-month follow-up postoperatively. Mean stone size was 19.7 ± 9.4 (range 8 to 31 mm). Twenty patients had upper ureteral and 64 patients had intrarenal calculi. Two patients had bilateral renal calculi. Mean operation time was 78.2 ± 23.8 min (range 17 to 144 min). Two procedures (2.3%) in warfarin group were terminated due to persistent bleeding causing visual impairment. No transfusions were required. The mean serum hemoglobin levels did not change significantly (12.9 ± 3.7 to 12.2 ± 3.3 g/dL). No thromboembolic or cardiac adverse events were observed perioperatively. The double-j (DJ) ureteral catheterization time was 29.6 ± 9.3 days (range 14 to 68 days) and the hospital stay was 1.6 ± 0.6 days (range 1 to 4). The stone-free rate was 95.2% (80 patients) at 6 months. Flexible ureteroscopic Ho:YAG laser lithotripsy in patients requiring long-term anticoagulation therapy seems to be a safe and effective procedure and should be considered as a first-line treatment option in such patients for the surgical management of upper urinary tract stones.

Does Transient Cessation of Antiplatelet Medication Prior to Shock Wave Lithotripsy Have Any Safety Concern: Evaluation of the Short Term Safety Results

OBJECTIVE

The study aimed to evaluate the true safety of transient cessation of the antiplatelet medication before extracorporeal shock wave lithotripsy (SWL) on bleeding-related complications.

PATIENTS AND METHODS

Forty cases undergoing SWL for renal pelvic stones were included and depending on the use of antiplatelet medication they were divided into 2 groups namely: group 1, cases under antiplatelet medication in whom the medication was stopped before ESWL; and group 2, cases without any antiplatelet medication. Comparative evaluation of patient, stone and treatment-related parameters were done in both groups.

RESULTS

Although microscopic hematuria was present in all cases, the incidence of macroscopic hematuria was higher in cases undergoing antiplatelet medication when compared with the other cases. Regarding the microscopic hematuria again, the mean number erythrocytes per field of analysis was significantly higher in group 1 cases. The mean value of the hematoma size was similar in both groups.

CONCLUSION

Our findings indicate that SWL can be applied safely in patients under antiplatelet therapy following the cessation of medication for a certain period of time. However, among the cases treated with this concept in our study, we clearly observed that the incidence of procedure-related hematoma formation and macroscopic hematuria were more common in such cases than in the normal ones.

CUA Guideline: Management of ureteral calculi

The focus of this guideline is the management of ureteral stones. Specifically, the topics covered include: conservative management, medical expulsive therapy, active intervention with either shockwave lithotripsy (SWL) or ureteroscopy (URS), factors affecting SWL treatment success, optimizing success, and special considerations (e.g., pregnancy, urinary diversion). By performing extensive literature reviews for each topic evaluated, we have generated an evidence-based consensus on the management of ureteral stones. The objective of this guideline is to help standardize the treatment of ureteral stones to optimize treatment outcomes.

Thromboprophylaxis and bleeding diathesis in minimally invasive stone surgery

With populations ageing and active treatment of urinary stones increasingly in demand, more patients with stones are presenting with an underlying bleeding disorder or need for regular thromboprophylaxis, by means of antiplatelet and other medication. A practical guide to thromboprophylaxis in the treatment of urinary tract lithiasis has not yet been established. Patients can be stratified according to levels of risk of arterial and venous thromboembolism, which influence the requirements for antiplatelet and anticoagulant medications, respectively. Patients should also be stratified according to their risk of bleeding. Consideration of the combined risks of bleeding and thromboembolism should determine the perioperative thromboprophylactic strategy. The choice of shockwave lithotripsy, percutaneous nephrolithotomy or ureteroscopy with laser lithotripsy for treatment of lithiasis should be determined with regard to these risks. Although ureteroscopy is the preferred method in high-risk patients, shockwave lithotripsy and percutaneous nephrolithotomy can be chosen when indicated, if appropriate guidelines are strictly followed.

Extracorporeal shockwave lithotripsy vs. percutaneous nephrolithotomy vs. flexible ureterorenoscopy for lower-pole stones

Objectives

To review previous reports and discuss current trends in extracorporeal shockwave lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL) and ureterorenoscopy (URS). ESWL was recommended as the first-line treatment for small and intermediate-sized stones in the lower pole, while it is the standard treatment for large stones. However, the stone clearance rate after ESWL seems to be lower than that of stones in other locations. This seems to result from a lower rate of fragment passage, due to anatomical factors.

Methods

Reports on urinary stone disease were reviewed, assessing only publications in peer-reviewed, Medline-listed journals in the English language (publication years 1990–2011).

Results

Recent experience with flexible URS (fURS) for intrarenal stones showed that excellent stone-free rates can be achieved. With increasing experience and technically improved equipment, fURS has become an alternative to ESWL for small and intermediate-sized renal stones. Furthermore, several authors reported successful retrograde treatment for large renal stones, proposing fURS as an alternative to PCNL. However, the major drawbacks are long operating times and commonly, staged procedures, which is why PCNL remains the method of choice for such stones.

Conclusions

Considering the currents trends and evidence, the 2012 update of the European Association of Urology Guidelines on Urolithiasis has upgraded the endourological treatment of kidney stones. Individual factors such as body habitus, renal anatomy, costs and patient preference must be considered.

Safety of ESWL in elderly: evaluation of independent predictors and comorbidity on stone-free rate and complications

AIM

Urinary stone disease affects people of all ages. With its satisfactory efficacy ranges in all age groups and lack of side-effects, extracorporeal shock wave lithotripsy (ESWL) has become the preferred treatment modality for uncomplicated renal and proximal calculi ≤ 20 mm. In the present study, we aimed to assess the safety and efficacy of the ESWL treatment in elderly patients.

METHODS

A retrospective study was carried out on patients aged over 65 years who underwent shock wave lithotripsy at our Department from 2009 to 2011, with a Siemens Lithostar electromagnetic shockwave lithotripter. A total of 231 patients (157 males, 74 females) out of 1694 (13.6%) were studied. The patients were divided into two groups (group 1 = 65-70; group 2 >70). The effect of age and other possible predicting factors (sex, stone localization and stone size) were investigated. Concomitant diseases and related complications were also evaluated.

RESULTS

An overall stone-free rate (SFR) of 82.2% was found. The influence of sex on SFR was non-significant. There was no significant difference when comparing SFR between the age groups. When patients were divided into those with renal and ureteral stones, the SFR were 94.4% and 67.6% (P < 0.01), respectively. The SFR of the stone size groups, ≤ 10 mm and > 10 mm were 80% and 84.4%, respectively. Comorbidity was present in 148 patients. Complications were noted in 56 of 231 patients. Of 56 patients, 43 had minor complications and 13 major complications.

CONCLUSION

ESWL seems to be an effective first-line treatment choice for urinary stones in elderly patients with careful patient selection and personalized preparation.

Shock wave lithotripsy in patients requiring anticoagulation or antiplatelet agents

Extracorporeal shockwave lithotripsy (SWL) remains the only truly minimally invasive procedure for the treatment of upper tract nephrolithiasis. Recently, there has been a recent rise in the patients on antiplatelet agents. Therefore, the aim of the present study is to review the literature available regarding SWL in these high-risk patients requiring anti-coagulation therapy. Alternative therapies to SWL are also presented.

Shock-wave lithotripsy in the elderly: Safety, efficacy and special considerations

Purpose

Shock-wave lithotripsy (SWL) for elderly patients can be challenging. Patients often have a long-standing complex stone burden and significant comorbidities. We report a cohort of patients aged ⩾70 years who were treated by SWL, with special attention to treatment outcomes, complications and the need for adjuvant procedures.

Patients and methods

Over a period of 4 years, 2311 patients were treated with SWL in a tertiary referral centre. Among these patients, 137 were aged ⩾70 years (5.9%). Patient and stone data were obtained from an electronic database and the patients’ electronic medical records were reviewed.

Results

During the pre-procedural assessment, 29 patients (21.2%) were considered to be at high anaesthetic risk, due their comorbidities (American Society of Anesthesiology score 3+). In terms of stone burden, 16 stones (11.7%) were located in the distal ureter (mean stone diameter 7.9 mm) and 28 (20.4%) were in the proximal ureter (mean diameter 10.1 mm). In the kidney, 54 stones (39.4%) were in the renal pelvis, upper or mid calyx (mean diameter 10.6 mm), while 39 stones (28.5%) were in the lower calyx (mean diameter 10.1 mm). The median (range) number of SWL sessions per patient was 2.0 (1–3). The overall stone-free rate achieved by SWL alone was 63.5% (65.9% for ureteric stones and 62.4% for renal stones). In total, 38 patients (27.7%) had an adjuvant procedure to achieve stone clearance (ureteroscopy in 23, PCNL in 14 and laparoscopic ureterolithotomy in one case). Apart from six cases (4.3%) of ureteric obstruction due to steinstrasse, there were no severe complications noted.

Conclusions

The management of elderly patients presenting with urolithiasis is challenging, due to the presence of significant comorbidities. Careful assessment of an integrated management plan for geriatric patients with urolithiasis is essential, and SWL still remains a safe and efficient first-line tool in well-selected cases.

Stone treatment and coagulopathy

OBJECTIVE

The aim of this retrospective study was to evaluate treatment protocols and results of upper tract stone treatment in patients with clotting disorders.

METHODS

In a 6-year period, 6,827 stone interventions (ESWL or endourologic procedures) were performed in 5,739 patients. Thirty-five (0.61%) patients suffered from a variety of systemic clotting disorders or were anti-coagulated. Clotting disorders were corrected by specific therapy prior to any intervention. A total of 76 interventions were performed consisting of ESWL, ureteroscopy (URS), percutaneous nephrolithotomy (PNL), ureteric stenting or percutaneous nephrostomy.

RESULTS

All patients became stone-free within 3 months or had clinically insignificant residual fragments. Severe complications were observed in 10/76 (13.1%) interventions. ESWL was successful in 88.9% (16/18) of patients, but associated with a 33.3% (6/18) complication rate; 27.8% (5/18) of patients required auxiliary procedures. URS and PNL were successful in all cases and complications occurred in 0% (0/7) and 33% (1/3) of patients, respectively. Time to complete stone clearance after ESWL was 32.0+/-49.3 days compared with a mean of 19.4+/-28.6 days in a non-coagulopathy control group; no difference was observed for endourologic procedures. Average costs of treatment in patients undergoing ureteroscopy was higher in patients with coagulopathy (4,611 versus 2,342); however, the difference was less pronounced compared with ESWL (6,070 versus 1,731).

CONCLUSION

Patients with coagulopathy have a higher rate of complications despite apparently normal clotting parameters during treatment and hospitalisation was prolonged. The efficacy of ESWL was lower in patients with coagulopathy and we currently favour endoscopic procedures for stone removal in this patient group.

Update on shock wave lithotripsy technology

PURPOSE OF REVIEW

Since the first patient was successfully treated with extracorporeal shock wave lithotripsy in 1980, its rapid acceptance and widespread use have championed this form of stone therapy as the treatment of choice for the majority of renal and ureteral calculi. Worldwide clinical series have documented the efficacy and safety of shock wave lithotripsy.

RECENT FINDINGS

Shock wave lithotripters have undergone modifications of the source for generation of shock waves, focusing, and even localization techniques since the introduction of the original Dornier HM3 lithotripter. Yet the basic concepts remain the same: to produce an acoustic wave that can be focused at a specific location for stone fragmentation. Safety and efficacy of the different generations of lithotripters is well documented. Indications and utilization of shock wave lithotripsy have expanded, with clinical efficacy approaching or exceeding that of other modalities of minimally invasive surgery. Complications, however, can arise as a result of shock wave therapy.

SUMMARY

This review provides an update of the latest shock wave technology, reviewing the clinical indications and efficacy of treatment and discussing the potential adverse events associated with shock wave lithotripsy.