Economics of Stone Management

Objective:

Cost has become an important factor, in addition to efficacy and morbidity, in determining the best therapeutic modality for a variety of disease states. We sought to evaluate the role of cost in the management of urolithiasis.

Methods:

A comprehensive literature search was performed to identify articles addressing the issue of cost in the medical and surgical management of renal and ureteral calculi. Published cost analyses and cost comparisons were critically reviewed to arrive at conclusions regarding the most cost-effective approach to acute stone events, surgical treatment and prophylaxis.

Results:

The cost of medical care, surgical treatment and medication varies widely across health care systems, resulting in differing conclusions with regard to cost-effective treatment strategies. In general, for renal calculi, percutaneous nephrostolithotomy (PCNL) is more cost effective than shock wave lithotripsy (SWL) for stones, while SWL may be cost-effective for smaller stones. For ureteral stones, observation is the least costly treatment strategy, but among surgical options, URS is less costly than SWL. For single and recurrent stone formers, prophylactic strategies involving drug therapy are more costly than conservative therapy involving dietary measures alone, but yield fewer stone recurrences.

Conclusions:

To determine the most cost-effective treatment strategy for the management of renal or ureteral calculi, the efficacy, cost and complication rates of each procedure, as well as the cost of retreatment for failures must be taken into consideration. International cost comparisons are limited by differing degrees of subsidization of components of health care, such as medication or surgery. Decision tree modeling allows determination of the most cost-effective treatment approach in any given health care system or institution.     

Comparison of percutaneous nephrolithotomy and ureteroscopic lithotripsy in the management of impacted, large, proximal ureteral stones

The optimal treatment for large, impacted, proximal ureteral stones remains controversial. We report our experience and compare treatment outcomes in patients with single, impacted, proximal ureteral stones undergoing percutaneous nephrolithotomy (PCNL) and ureteroscopic lithotripsy (URSL). Between January 2005 and January 2006, a total of 53 consecutive patients with solitary, impacted, proximal ureteral stones > 15 mm in diameter who had undergone PCNL or URSL treatments were enrolled in this study. The mean age was 48.5 +/- 11.8 years. PCNL and URSL were performed in 22 and 31 patients. Stone burdens in the PCNL and URSL groups were 232.8 +/- 113.2 mm2 and 150.3 +/- 70.3 mm2, respectively. The efficiency quotient (EQ) for the PCNL and URSL groups was 0.95 and 0.67, respectively. The stone-free rate at the 1 month follow-up was 95.4% in the PCNL group and 58% in the URSL group (p < 0.001). Two patients in the PCNL group had blood loss requiring transfusion. Eight patients had stones showing upward migration during the URSL procedure, and these stones were subsequently treated by extracorporeal shock wave lithotripsy and PCNL. For an impacted, proximal ureteral stone > 15 mm in diameter, PCNL had better stone-free rates and could simultaneously treat coexisting renal stones. However, URSL had the advantages of shorter operative times, shorter postoperative hospital stays, and fewer postoperative complications.     

National High Blood Pressure Education Program (NHBPEP) review paper on complications of shock wave lithotripsy for urinary calculi.

This decade has witnessed dramatic advances in the surgical management of urinary calculi. Today, most stones can be removed by minimally invasive means. In fact, the treatment of choice in 60% to 90% of patients with renal and ureteral calculi that need to be surgically removed is extracorporeal shock wave lithotripsy (ESWL). This article reviews indications for ESWL and discusses deleterious effects of ESWL.     

Medical and Economic Aspects of Extracorporeal Shock Wave Lithotripsy

Extracorporeal shock wave lithotripsy (ESWL) is the method of choice for most renal and ureteral calculi. However, endoscopic procedures such as ureteroscopy or percutaneous nephrolithotomy are being more and more performed as primary treatment alternatives in clinical routine. This development may result from the sometimes unsatisfying results of ESWL. While this is often explained by a lower efficacy of last-generation machines, an often unrecognized explanation is the impact of a less well trained urologist. To achieve best results it is mandatory that fundamental knowledge about shock wave physics and disintegration mechanisms are available. In Germany, the reimbursement system between outpatient and inpatient departments is totally separate. This leads to difficulties in clinical practice. We believe that patients at risk for complications, such as ureteral stones, urinary tract infections or high age, benefit from inpatient treatment, while uncomplicated renal stones can safely be treated on an outpatient basis. Regular application and training of ESWL will aid an optimization of its results and acceptance.     

Extracorporeal shock wave lithotripsy (ESWL) for common bile duct stones]

We treated twenty-three patients with common bile duct stones (12 female, 11 male, mean age: 67.1 years) by Extracorporeal Shock Wave Lithotripsy (ESWL). The stones were focused by ultrasonic or choledochographic localization. The twenty-three patients received 53 ESWL treatments consisting of mean 2357 shocks per treatment at mean 18 kV. We performed ESWL in five cases with endoscopically unextractable common bile duct stones after endoscopic sphincterotomy (EST). In these cases, ESWL permitted stone disintegration and successful endoscopic extraction of the fragments. We performed ESWL in eighteen cases with common bile duct stones without EST. In fifteen of the eighteen cases (83%), fragmentation was achieved. The stone fragments were spontaneously discharged in ten cases (56%) after a median of 4 days following ESWL. In five cases, adjutant endoscopic procedures were performed. The complete fragmentation and the clearance rate for stones of diameter of less than 10 mm were higher than that for stones of diameter of more than 11 mm. In the cases with the stones of diameter of more than 10 mm, there is a very strong possibility that complete clearance is achieved by ESWL alone. No correlation was obtained for the effective results according to pretreatment number of stones. In eight of thirteen cases (62%) with gall bladder stones, complete clearance was achieved without EST. ESWL without EST can be thought as a rational treatment for preserving the function of papilla of Vater in the case of cholecysto-choledocholithiasis.     

Current surgical approaches to nephrolithiasis

Shock wave lithotripsy is the cornerstone of the modern management of surgical stone disease and is the procedure of choice for small stones in uncomplicated situations. As complexity increases and as the stone size increases, percutaneous lithotripsy becomes more important. Ureteroscopy is preferable for lower ureteral stones and is useful for many mid and upper ureteral stones. Occasional large, complicated stones, or stones that can be reached no other way, require open surgery. Successful management of a wide variety of patients with urinary calculi requires the recognition that multiple forms of therapy are necessary. Identification of the situations best managed by these different treatments will ensure optimal management of patients with surgical stone disease.     

Stone management in children

The extracorporeal shock-wave lithotripsy (ESWL) is still the treatment of choice for almost all stones in children. But with advances in instrumentation, endourological procedures are being performed more frequently in younger patients. Especially in the treatment of distal ureteral stones retrograde ureteroscopy now competes with ESWL. Finally, the recent literature supports percutaneous nephrolithotomy as a safe and effective treatment option for large renal calculi and staghorn calculi. This gives the clinician the opportunity to choose from a wide range of treatment alternatives. Proper treatment planning, technique and availability of appropriate instrumentation are important to achieve an optimal outcome.     

经皮肾微造瘘输尿管镜术治疗上尿路结石(附8例报告)

采用经皮肾穿刺置入造瘘管建立微造瘘通道后，同期经皮肾输尿管镜气压弹道碎石治疗上尿路结石患者8例。结果结石一期一次取净4例，3－5日二次取净2例，其余2例二次取石后肾下极肾盏内仍有小块结石残留，经体外震波碎石后结石排空。8例患者平均住院7．5天，术中及术后未出现并发症。认为Trocar造瘘管创伤小，术中出血及并发症少，可进入大部分肾盏及输尿管上段，视野清晰，大块结石碎屑能通过管腔冲出体外，取石效率提高；术毕能置入F14或F12气囊尿管，肾盂引流畅通，气囊稍牵拉有利于术后止血。     

Ten years experience with piezoelectric extracorporeal shockwave lithotripsy of gallbladder stones

BACKGROUND: A critical review of the experience with extracorporeal shockwave lithotripsy (ESWL) of gallbladder stones is needed to clarify whether this method should continue to be applied to patients. METHODS: Patients with symptomatic gallbladder stones were treated by piezoelectric ESWL according to a prospective protocol between 1988 and 1997. ESWL treatment was limited to a maximum of three (solitary stones <20 mm diameter) to five sessions (larger solitary or multiple stones) and 3000 pulses per session. Univariate and multivariate analyses of pretreatment and treatment variables were performed to investigate their impact on fragmentation efficacy and stone clearance. A tree-based analysis was used to identify prognostically homogenous subgroups of individuals with maximum benefit from ESWL. RESULTS: Four hundred and eight patients, 76% female and 24% male, with a mean age of 46 (SD, 13) years, were selected for evaluation. Cox regression analysis identified three pretreatment variables with significant prognostic impact: (1) number of gallstones >1 (relative risk, 2.6 (95% CI, 1.9-3.5)), (2) size of stones >17 mm (1.7 (1.4-2.2)), and (3) computed tomography (CT) density of stones >55 Hounsfield units (H) (1.4 (1.1-1.8)). According to tree-based analysis, the stone clearance rate after 1 year was 85% (95% CI, 75-91%) for solitary stones <16 mm, 79% (70-86%) for solitary stones > or =16 mm with a CT density <84 H, 45% (32-55%) for solitary stones > or =16 mm with a CT density > or =84 H, and 42% (30-51%) for multiple stones. Five years after stone clearance, recurrence occurred in 43% of patients (95% CI, 39-47%). CONCLUSIONS: ESWL treatment showed an acceptable stone clearance in the case of small solitary gallbladder stones (<16 mm) or larger solitary stones with a CT density <84 H, but a very low success rate in the case of multiple stones. The poor long-term success, however, is an important argument against the use of ESWL of gallbladder stones.     

Flank suspended supine position for percutaneous nephrolithotomy

Aims. Prone and supine positions for percutaneous nephrolithotomy are widely used but have their drawbacks. We report a new positioning method called "flank suspended supine position" (FSSP) for PCNL and describe our experience with PCNL in this position to evaluate its safety and efficacy. Methods. Retrospective study of 150 cases of renal stone patients treated with PCNL in a new position called flank suspended supine position (FSSP) from June 2009 to July 2010. All patients were treated with PCNL in FSSP under epidural anesthesia. Operation time, bleeding rate, stone free rate, and complications were recorded. Results. All patients tolerated FSSP. Mean operation time was 78.29±26.13 min. Initial stone-free rate was 83%. For those with residual stones (26 cases), 18 were stone-free after a second PCNL, 8 after extracorporeal shock wave lithotripsy (ESWL). Mean hospital stay was 7.63±2.39 days. No penetrating injury of the pleural cavity or injury to visceral organs was reported. Summary. FSSP is an effective and safe position for PCNL in our hands and its effectiveness relative to traditional prone position needs to be determined in future randomized studies.     

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. Geriatr Gerontol Int 2012; 12: 413–417.     

When is ESWL of small calyceal stones indicated?

PURPOSE: To evaluate the indications for and the outcomes of extracorporeal shock wave lithotripsy (ESWL) of calyceal stones <5 mm, we prospectively studied a series of 25 patients scheduled for treatment. MATERIALS AND METHODS: Between January 1994 and June 1995, 15 males and 10 females with a mean age of 44 years (median 43; range 4 to 70 years) underwent ESWL of calyceal stones <5 mm using an unmodified HM3 Dornier lithotriptor. RESULTS: Indications for ESWL included 17 patients (68%) suffering from back and flank pain, 3 patients (12%) with gross hematuria and 1 patient (4%) with recurrent episodes of pyelonephritis. Six patients (24%) were asymptomatic. Evaluation 3 months after ESWL revealed that of the 17 patients with flank pain, 13 (76%) had complete resolution of pain and 4 (24%) had partial resolution of pain and there had been no further episodes of gross hematuria or pyelonephritis in the previously affected patients. At 3-month follow-up, of the 31 kidneys treated, plain radiography were available in 29; 20 (69%) were clear and 9 (31%) had small residual fragments. CONCLUSIONS: Calyceal stones <5 mm in maximum diameter can cause significant symptoms such as pain, hematuria and infection and should not be dismissed as inconsequential. When no other obvious cause is apparent, these small stones should be treated with a high likelihood of resolution of symptoms and clearance. ESWL should not be withheld in patients with small asymptomatic calculi who request or require treatment for fear of unexpected colic or stone growth.     

Recurrent renal stone disease-advances in pathogenesis and clinical management

Kidney stones are common in industrialised nations: up to 15% of white men and 6% of all women will develop one stone, with recurrence in about half these people. Risk factors for formation of stones include urinary promoters (calcium, urate, cystine, and sodium) and urinary inhibitors (magnesium, citrate, and nephrocalcin). Acute renal colic can be precipitated by dehydration and reduced urine output, increased protein intake, heavy physical exercise, and various medicines. Such colic manifests as severe loin pain and can be accompanied by frequent urination, dysuria, oliguria, and haematuria. Documentation of stone characteristics is extremely important: type, size, location, and underlying metabolic abnormalities. Such details can be obtained with a combination of biochemical investigations, microscopic examination of urine under polarised light, and an intravenous pyelogram. Ultrasonography and plain abdominal radiographs are also useful, especially for patients unable to tolerate an intravenous pyelogram. Acute therapy includes complete pain relief, rehydration, and encouragement of diuresis. Long-term management encompasses education of patients with regard to diet and fluid intake, control of calciuria, citrate replacement, and treatment of any underlying urinary-tract infection or metabolic abnormality. Stones smaller than 5 mm normally pass spontaneously, whereas larger stones, as big as 2 cm, are best treated with extracorporeal shock-wave lithotripsy. All physicians should have a clear understanding of the pathogenesis and clinical management (acute treatment and prevention of recurrence) of renal stone disease.     

Current aspects of stone therapy

More than 30 % of all admissions to an urologic clinic are for the treatment of urinary stones. In almost all cases, the treatment is minimally invasive employing extracorporeal shock wave lithotripsy (ESWL), ureterorenoscopy (URS) or percutaneous nephrolithotomy (PCNL). Technical advances in endourology and a growing expertise in ESWL led to a decline in ESWL and an increase in endoscopic techniques. In comparison with ESWL, the endoscopic techniques are more invasive but in most cases achieve a stone free state faster. With the introduction of diagnosis related groups (DRG), the economic aspect of stone therapy is gaining in importance. Stone prevention leads to a cost reduction in the health care system, justifying the use of an appropriate stone metaphylaxis. This review article presents the current recommendations for interventional urinary stone therapy and lists the options of conducting both medical and economically rational therapy.     

Dietary aspects of uric acid stone disease

Kidney stones composed of uric acid present a treatment challenge, particularly in terms of successful prevention of recurrence over the long term. Between 5-12% of all stone patients form calculi composed partially or completely of uric acid. These stones have traditionally been treated with a combination of pharmacological and surgical techniques. The role of diet and fluids in the pathogenesis and management is gradually being recognized and there is potential for dietary intervention to become a major treatment modality for this type of stone. This paper discusses the stone formation process, the metabolism or uric acid and its physical and chemical properties. Specific risk factors for uric acid calculi formation are covered. Dietary protein is reviewed in detail. A comprehensive strategy for the dietary management of uric acid renal calculi disease is suggested.     

Extracorporeal shock wave lithotripsy of large difficult common bile duct stones: Efficacy and analysis of factors that favor stone fragmentation

Background and Aim:  Difficult common bile duct stones (CBD) are those not amenable to extraction by the standard technique of sphincterotomy followed by use of a Dormia basket or balloon. The role of extracorporeal shock wave lithotripsy (ESWL) in stone fragmentation and clearance of difficult CBD stones and the factors which favor fragmentation were prospectively evaluated in the present study.
Methods:  A total of 283 patients with large CBD stones were subjected to ESWL. A maximum of 5000 shocks was delivered per session until CBD stones were fragmented to less than 5 mm diameter. CBD was cleared by biliary endotherapy using a basket or balloon. Outcome was assessed by CBD clearance.
Results:  Total CBD clearance was achieved in 239 patients (84.4%) and partial CBD clearance in 35 patients (12.3%). Three or fewer sessions of ESWL were required in 74.6% of patients. Minor complications were seen in 45 patients (15.9%). There was no procedure-related mortality. Epidural anesthesia, shock frequency of 90/min, radiolucent calculi and presence of fluid around the calculus helped in better fragmentation.
Conclusion:  A high success rate, negligible complications and non-invasive nature of the procedure make ESWL a useful tool for removing large CBD stones.     

Assessment of stone composition in the management of urinary stones

Several explanations have been suggested to account for the failure of extracorporeal shockwave lithotripsy (ESWL) treatment in patients with urinary stones, including large stone volume, unfavorable stone location or composition and the type of lithotriptor used. Unfavorable stone composition is considered a major cause of failure of ESWL treatment, and consequently knowledge of the stone composition before treatment is initiated is desirable. Plain abdominal radiographs cannot accurately determine either stone composition or fragility, and although the CT attenuation value in Hounsfield units (HU) (that is, normalized to the attenuation characteristics of water) is useful, this parameter has limited value as a predictor of stone composition or the response to ESWL treatment. By contrast, stone morphology as visualized by CT correlates well with both fragility and susceptibility to fragmentation by ESWL. For patients prone to recurrent calculi, analyses of stone composition are especially important, as they may reveal an underlying metabolic abnormality. The development of advanced imaging technologies that can predict stone fragility is essential, as they could provide extra information for physicians, enabling them to select the most appropriate treatment option for patients with urinary stones.     

Extracorporeal shock wave lithotripsy of pancreatic duct stones and patient factors related to stone disintegration

Background: Background: Stones in the main pancreatic duct (MPD) are difficult to remove by endoscopic devices alone in some patients who have chronic pancreatitis. We treated these patients with extracorporeal shock wave lithotripsy (ESWL) and analyzed the patient factors related to disintegration. Methods: Twenty-four patients were treated with ESWL alone or with combined endoscopic-ESWL to disintegrate or remove MPD stones. Results: Ten patients were treated by ESWL alone and 14 by combined endoscopic-ESWL. A total of 19 patients (79%) were effectively treated by either method. The mean MPD diameter decreased significantly after ESWL. In most of the patients who had chronic abdominal symptoms, these symptoms were relieved at discharge. Severe side effects of complications did not occur during ESWL therapy. Acute abdominal symptoms and a significant increase in the white blood cell count, total bilirubin, and aspartate aminotransferase were observed only immediately after ESWL. Although there were no significant differences, we observed that the patients with a higher stone disintegration success rate showed the following factors: (1) female, (2) non-alcoholic pancreatitis, (3) younger age, (4) shorter duration of symptoms, (5) smaller stones, and (6) a lower Hounsfield unit value of stones. Although about half of the patients had recurring abdominal symptoms and stones during a follow-up period of 12 months, the stones which caused relapse in short-term intervals were disintegrated easily by ESWL. Conclusions: We may consider the application of ESWL therapies for patients who show the factors associated with easily disintegratable stone conditions. These therapies are highly effective and relatively safe procedures for pancreatic duct stones in such patients. Received: February 2, 2001 / Accepted: October 5, 2001     

Balloon-endoscopic retrograde pancreatography employed for extracorporeal shockwave pancreatic lithotripsy

Painful pancreatolithiasis may be alleviated by removing pancreatic stones that occlude the pancreatic duct. In five patients with pancreatolithiasis, preoperative endoscopic retrograde pancreatography showed filling defects in the dilated main pancreatic duct. Endoscopic sphincterotomy and subsequent attempts at stone extraction with a basket and/or a balloon catheter failed to achieve complete clearance of stones. Extracorporeal shockwave lithotripsy (ESWL) was performed under fluoroscopic pancreatographic control, using an indwelling balloon catheter; complete removal of the stones was achieved. Balloon pancreatography facilitated visualization of radiolucent stones during ESWL. Insertion of the balloon catheter is easier than using a nasopancreatic tube, even when there are calculi near the duodenal papilla. This is method extends the repertoire of choices for focusing shockwaves on radiolucent pancreatic stones during ESWL.     

Pulverisation of calcified and non-calcified gall bladder stones: extracorporeal shock wave lithotripsy used alone.

Using a modified electromagnetic lithotripter (Siemens), extracorporeal shock wave lithotripsy (ESWL) was performed in 260 patients with gall bladder stones. Exclusion criteria for treatment were a non-functioning gall bladder, subcostal gall bladder location, and multiple stones occupying more than three quarters of the gall bladder volume. Stone pulverisation was the end point of ESWL. The number of shock wave discharges and sessions was not limited. Pulverisation was achieved in 250 patients (96.1%) after a median of three ESWL sessions (range 1-21). The number of sessions required depended upon stone composition and burden. More than three sessions were required in 60.2% of patients with calcified stones compared with 35.9% of patients with non-calcified stones (p < 0.001). 65.8% of patients with stones measuring more than 30 mm in total diameter required more than three sessions compared with 42.9% of patients with a stone burden less than 30 mm (p < 0.01). At 18-24 (8-12) months follow up, stone clearance was achieved in 94.3% (80.4%) of patients with non-calcified stones, compared with 89.5% (76.8%) in patients with calcified stones and in 75% (71.4%) of patients with a total stone diameter more than 30 mm compared with 95.7% (80.4%) for patients with a total stone diameter less than 30 mm (p < 0.05). ESWL related complications (gross haematuria) occurred in three patients. Thirty six (13.8%) patients experienced biliary colic; four had cholecystectomy, and five endoscopic papillotomy because of common bile duct obstruction. Stone recurrence was seen in 5.3% of patients over a follow up period of up to two years (median 16.6 months).