Metabolomic profiling in patients undergoing Off-Pump or On-Pump coronary artery bypass surgery.

BACKGROUND: Coronary artery bypass surgery can be performed without (Off-Pump) or with cardiopulmonary bypass (On-Pump). Extracorporeal circulation and cardioplegic arrest may cause alterations in the plasma metabolome. We assessed metabolomic changes in patients undergoing On-Pump or Off-Pump coronary artery bypass surgery. METHODS: We assessed five analyte classes (41 acylcarnitines, 14 amino acids, 92 glycerophospholipids, 15 sphingolipids, sugars, lactate) using a mass-spectrometry-based kit (Biocrates AbsoluteIDQ® p150) in paired arterial and coronary sinus blood obtained from 10 consecutive On-Pump and 10 Off-Pump patients. Cardioplegia for On-Pump was warm blood Calafiore. On-Pump outcomes were corrected for hemodilution through crystalloid priming. RESULTS: Demographic data were equal in both groups with normal ejection fraction, renal and liver function. Patients received 2.25 ± 0.64 bypass grafts. All postoperative courses were uneventful. Of 164 measured metabolites, only 13 (7.9%) were altered by cardiopulmonary bypass. We found more long-chain acylcarnitines Off-Pump and more short-chain acylcarnitines On-Pump. Glycerophospholipids showed lower concentrations On-Pump and arginine (as the only different amino acid) Off-Pump. Interestingly, plasma arginine (nitric oxide precursor) concentration at the end of surgery correlated inversely with postoperative vasopressor need (r = -0.7; p < 0.001). Assessing arterial/venous differences revealed phosphatidylcholine-production and acylcarnitine-consumption. These findings were unaffected by cardiopulmonary bypass, cardioplegia or temporary vessel occlusion during Off-Pump surgery. CONCLUSIONS: Cardiopulmonary bypass and warm blood cardioplegia cause only minor changes to the metabolomic profile of patients undergoing coronary artery bypass surgery. The observed changes affected mainly acylcarnitines. In addition, there appears to be a relationship between arginine and vasopressor need after bypass surgery.

Idiopathic retroperitoneal fibrosis: a role for mycophenolate mofetil.

PURPOSE: Idiopathic retroperitoneal fibrosis (IRPF) is an unusual progressive illness for which consistent therapeutic recommendations have not been devised. The present report describes a collaborative nephrology and urology approach to distinguish IRPF from secondary disease and then combine necessary acute surgical or radiological intervention with short-term corticosteroid and with mycophenolate mofetil (MM) to facilitate steroid tapering and long-term management. MATERIALS AND METHODS: 21 patients have been evaluated and followed over a 7-year period, 16 with characteristic IRPF and 5 with secondary retroperitoneal disease. IRPF patients initially received high-dose corticosteroid and MM. We report clinical follow-up along with imaging studies of the retroperitoneum and related organs, serologic markers for systemic disease, and nonspecific acute-phase reactants as indicators of ongoing disease activity. RESULTS: Among IRPF patients, uniform success in stabilizing clinical signs and symptoms, radiological disease in the retroperitoneum and associated organs, and inflammatory indicators have been observed. Corticosteroid therapy can be limited to 6 months or less and MM to approximately 2 years, all with substantial impact on the natural history of IRPF. CONCLUSIONS: This is not a randomized, controlled trial, and patients were often referred with prior complications and/or treatments, however, the systematic approach and consistent results support the utility of MM as a safe and effective choice for long-term stabilization in IRPF.

Surgical therapy of ventricular arrhythmias.

Since the advent of implantable cardioverters/defibrillators (ICD) and percutaneous ablation, surgery for the treatment of ventricular arrhythmia has decreased tremendously. Nevertheless, surgical treatment of ventricular arrhythmias is still required, especially for cases where ICD discharge occurs very frequently or in patients with other indications for surgery. The choice of surgical therapy may range from radiofrequency- or cryoablation of a single focus (identified either intra- operatively or percutaneously) to more extensive surgical procedures such as surgical ventricular reconstruction with endocardial resection or even resection of the right ventricle and the creation of a cavo-pulmonary circulation for malignant arrhythmias and right ventricular failure in patients with arrhythmogenic right ventricular dysplasia. However, the choice of surgical procedure should be made based on the pathomechanism of the arrhythmia. This is important because any incision in the left or right ventricle or percutaneous ablation may also be the cause for ventricular arrhythmia. In this short review we will describe the most common underlying substrates for ventricular arrhythmia, indications for surgery, the techniques used for treatment and the results achieved. We will conclude that for most cases of patients with ventricular arrhythmia undergoing surgery, ischemia and the presence of a scar after myocardial infarction is the underlying cause and revascularization plus surgical ventricular reconstruction with endocardial resection may be the best treatment option.

Flexible ureteroscopy in conjunction with in situ lithotripsy for lower pole calculi.

OBJECTIVES: To demonstrate the efficacy and safety of ureteroscopy as a compromise in treating small and intermediate-size lower pole calculi. The optimal management of lower pole calculi remains controversial. Shock wave lithotripsy is associated with minimal morbidity but with suboptimal stone clearance rates. Conversely, percutaneous nephrostolithotomy has greater morbidity but stone-free rates greater than 90% regardless of size. METHODS: Seventy-two patients underwent ureteroscopy for lower pole calculi 2 cm or less (mean 8.7 mm) during a 3-year period. To minimize confounding, 11 patients with additional calculi at other ipsilateral renal sites and 1 patient with large (2.4 cm each) bilateral calculi were excluded. Two patients with bilateral lower pole calculi and four who required a second procedure were included in the analysis. Thus, the final cohort consisted of 60 patients who underwent 66 procedures. RESULTS: Of patients with follow-up longer than 1 month, 79% were stone free after a single procedure, and this improved to 88% after a second procedure in 4 patients. All 7 patients with follow-up less than 1 month had a reduction in stone burden after successful fragmentation. Overall, 8 patients required an auxiliary procedure. No intraoperative complications, and 7 (11%) postoperative complications occurred. CONCLUSIONS: Ureteroscopy for lower pole calculi is associated with minimal morbidity and stone-free rates comparable to shock wave lithotripsy for smaller stones. The greatest utility of ureteroscopy is in the management of intermediate-size calculi, for which it has substantially higher stone-free rates and lower repeated treatment rates than does shock wave lithotripsy.

Arterial pseudoaneurysm complicating endoscopic fulguration of upper urinary tract urothelial carcinoma.

We report a case of intrarenal arterial pseudoaneurysm after ureteroscopic fulguration of recurrent urothelial carcinoma. An asymptomatic 90-year-old woman underwent uneventful cauterization of two small papillary urothelial carcinomas. One month postoperatively, the patient presented with gross hematuria. Angiographic evaluation revealed a small pseudoaneurysm in the distal upper pole branch of the left renal artery, corresponding to the site of recent tumor fulguration. Angioembolization of this lesion was successfully performed. Acute or subacute gross hematuria after endoscopic tumor ablation may be due to an arterial pseudoaneurysm. Angiographic evaluation is critical for the successful diagnosis and treatment of this complication.

Collagen implant for treating stress urinary incontinence in women with urethral hypermobility.

PURPOSE: We evaluated the use of collagen in women with stress urinary incontinence and urethral hypermobility. MATERIALS AND METHODS: We treated 90 patients with stress urinary incontinence and urethral hypermobility with 1 to 3 injections of Contigen implant (C. R. Bard, Inc., Covington, Georgia) between June 1996 and October 1998. Observations at 3, 6 and 12 months included continence grade, 7-day voiding diaries and quality of life questionnaires. Abdominal leak point pressure was determined at baseline and 12 months. RESULTS: At the 6-month followup 68 patients remained in the study, of whom 30 (44%) were dry and 24 (35%) were improved. Of the 58 patients who reached the 12-month followup 19 (33%) were dry and 19 (33%) were improved. Considering all patients entered into the study at 6 months 30 (33%) were dry and 24 (27%) were improved. Of the original 90 patients 19 (21%) were dry and 19 (21%) were improved at 12 months. The probability of maintaining initial improvement for 12 months was 44%. The success of bulking agent therapy was not predicted by the initial incontinence grade. Improved continence grade correlated with improved leak point pressure. CONCLUSIONS: This therapy is appropriate in women with urethral hypermobility who wish to avoid surgical risks and in those in whom surgery is ill advised.

Revision rate after artificial urinary sphincter implantation for incontinence after radical prostatectomy: actuarial analysis.

PURPOSE: We determined the actuarial revision rate for artificial urinary sphincters implanted in patients who were incontinent after radical prostatectomy. MATERIALS AND METHODS: We reviewed the records of 70 consecutive patients who were incontinent after radical prostatectomy and who underwent primary artificial urinary sphincter implantation at the University of Michigan between 1984 and 1999. Questionnaires were mailed to all patients with an indwelling device, and telephone calls were placed to those who did not respond to the mailing. Information about surgical revision and current continence status was obtained from chart review and questionnaire response. The Kaplan-Meier curves for actuarial freedom from operative revision were constructed. RESULTS: Of the 66 patients with available postoperative data 24 (36%) required reoperation at a mean followup of 41 months. The 5-year actuarial rate for freedom from any operative revision was 50%, and the corresponding rate for cuff revision was 60%. A single operative revision did not predispose the patient to further revision. Questionnaire data indicated a continence rate of 80% (range 0 to 2 pads). CONCLUSIONS: Approximately half of the patients who were incontinent after radical prostatectomy may expect to undergo operative revision within 5 years after artificial urinary sphincter implantation. Despite this high reoperation rate, an excellent level of continence is maintained.

Comparison of outcomes of ureteroscopy for ureteral calculi located above and below the pelvic brim.

OBJECTIVES: To compare the safety and efficacy of ureteroscopy performed for proximal and distal ureteral calculi in a contemporary cohort. Ureteroscopy has been used most often for distal ureteral calculi. However, advances in endoscopic equipment have facilitated access to the proximal urinary tract and have broadened the indications for ureteroscopy. METHODS: One hundred ninety-one patients underwent rigid and/or flexible ureteroscopy for ureteral calculi at the University of Michigan between January 1, 1997 and September 30, 1999. Only 7 patients with either bilateral calculi or steinstrasse were excluded. The final cohort consisted of 184 patients who underwent ureteroscopy for distal stones (n = 103) or middle/upper ureteral stones (n = 81). RESULTS: Bivariate analyses of pretreatment and perioperative characteristics were used to assess the sample population. The initial success rate for the distal and proximal ureteral calculi was 96% and 78%, respectively (P = 0.0008). After a "second-look" procedure in 4 and 7 patients with distal and proximal calculi, respectively, the success rate improved to 99% and 88%, respectively (P = 0.004). No differences were noted between groups regarding the intraoperative (P = 0.51) or postoperative (P = 0.85) complication rates. Multivariate logistic regression analysis confirmed that larger stone size (odds ratio 1.2, P = 0.0006) and proximal ureteral location (odds ratio 4.8, P = 0.01) are independent predictors of treatment failure. CONCLUSIONS: Ureteroscopic management of proximal and distal ureteral calculi is highly successful, and the difference in success rates has narrowed substantially. Currently, no greater risk is conferred to the patient for endoscopy of more proximal ureteral calculi.

Complications of ureteroscopy: analysis of predictive factors.

PURPOSE: Although overall and major complication rates of 10% to 20% and 0% to 6%, respectively, have been observed in large series of ureteroscopy, to our knowledge no systemic analysis to determine factors predictive of these complications has been reported. MATERIALS AND METHODS: We retrospectively reviewed all ureteroscopies performed at our institution for calculous disease from January 1997 through September 1999. A total of 322 procedures were performed by 5 attending surgeons. Intraoperative and immediate postoperative complications were identified. Bivariate and multivariate analysis was performed to identify associated factors with ureteral perforation and postoperative complications as the dependent variables. RESULTS: Bivariate analysis showed a significant association of ureteral perforation with increased operative time (p = 0.0001). In addition, we noted a significant association of postoperative complications with stones in the kidney (p = 0.0004), operative time (p = 0.05) and decreased surgeon experience (p = 0.0035) as well as a trend toward significance for the type of ureteroscope used (p = 0.0609). In multivariate logistic regression models ureteral perforation remained highly associated with operative time (p = 0.0005) when controlling for the other factors. Similarly decreased surgeon experience and a stone in the kidney were predictive of postoperative complications when controlling for the other factors (p = 0.004). CONCLUSIONS: Longer duration of the ureteroscopic procedure is strongly associated with ureteral perforation. The likelihood of immediate postoperative complications is greater when renal calculi are treated and less when the surgeon is more experienced.

Pediatric urolithiasis.

Urinary lithiasis in the pediatric population has evolved from a mere clinical curiosity to a disease process worthy of thoughtful and rigorous scientific study. All aspects of urinary lithiasis have undergone this evolution, including the epidemiology of stone formation in children, defining new modalities of radiologic imaging, and refining surgical techniques for stone treatment. These advancements and observations in pediatric stone disease are highlighted.

The natural history of lower urinary tract symptoms in black American men: relationships with aging, prostate size, flow rate and bothersomeness.

PURPOSE: Studies of lower urinary tract symptoms in men have been restricted to predominately white populations and these observations may not be generalized to black American men. A goal of the Flint Men's Health Study was to evaluate the prevalence of lower urinary tract symptoms in a community based sample of black American men. MATERIALS AND METHODS: We identified 721 eligible subjects after a 2-stage stratified sampling protocol of black American men residing in Flint, Michigan and an in-home interview. Of these men 364 (50%) completed the study protocol, including serum prostate specific antigen measurement, digital rectal examination, uroflowmetry and transrectal ultrasound. These men comprised our study group. Patients completed the American Urological Association (AUA) symptom and bothersomeness scores. Moderate to severe symptoms and impairment were defined as an AUA symptom score of greater than 7 and bothersomeness score of greater than 3, respectively. Data were stratified by 10-year age groups. RESULTS: Prostate volume increased, while the peak urinary flow rate decreased with increasing age (p <0.001). Total AUA symptom and bothersomeness scores were marginally associated with age (p = 0.08 and 0.01, respectively). Although only 8.2% of the men reported an enlarged prostate and 3% reported being on medical therapy for benign prostatic hyperplasia, moderate to severe lower urinary tract symptoms were reported by 39.6% and moderate to severe impairment was present in 35%. CONCLUSIONS: To our knowledge this is the first study to describe the prevalence of lower urinary tract symptoms and its associations with age, prostate size and peak flow rate in a black American population. A large proportion of the men in this study had from moderate to severe lower urinary tract symptoms, of whom many were undiagnosed and untreated. The AUA symptom score has the potential to identify these men and its validity in black Americans has now been established.

Routine placement of ureteral stents is unnecessary after ureteroscopy for urinary calculi.

OBJECTIVES: To report a matched comparison of patients with and without stenting after ureteroscopy for calculi, including middle or proximal ureteral and renal calculi. The elimination of routine stenting after ureteroscopy would prevent stent pain, minimize the need for re-instrumentation, and reduce costs-as long as efficacy and safety are not diminished. METHODS: Of 318 patients who underwent ureteroscopy, 81 (25%) did not have a ureteral stent placed. Of those, 51 were suitable for analysis and included patients with distal ureteral (n = 22), middle or proximal ureteral (n = 11), and renal calculi (n = 18). This cohort was matched to a stented group by stone size and location. RESULTS: The preoperative characteristics of the groups were similar. A stone-free rate of 86% and 94% was achieved in the stented and nonstented groups, respectively (P = 0.32). Complications in the nonstented group were less frequent (flank pain in 3 and postoperative nausea in 1) than in the stented group (hospital visits for flank pain in 12, persistent nausea and vomiting in 1, sepsis in 1, perinephric hematoma in 1, and urinary retention in 1) (total of 4 versus 16, P = 0.025). CONCLUSIONS: Ureteroscopy for distal ureteral stones without ureteral stent placement has been previously described. Our experience expands to include the elimination of stent placement after ureteroscopy for middle or proximal ureteral (22%) and renal (35%) calculi. Our data suggest that after ureteroscopies with short operative times and minimal ureteral trauma, ureteral stents may not be necessary, even if proximal ureteral or renal ureteroscopy has been performed.

Urinary tract erosions after synthetic pubovaginal slings: diagnosis and management strategy.

OBJECTIVES: To review our experience with the diagnosis and management of genitourinary tract erosions after pubovaginal sling placement. METHODS: Clinic and operative records from the urology and gynecology services at two university hospitals were reviewed, and 14 patients were identified who underwent surgical treatment for a urogenital tract erosion after pubovaginal sling placement. The presenting symptoms, physical findings, diagnostic procedures, surgical treatments, and outcomes were reviewed. RESULTS: Six vaginal erosions, six urethral and vaginal erosions, and two bladder erosions occurred. All were associated with synthetic sling or suture materials. Common symptoms included vaginal and urethral pain, irritative voiding symptoms, vaginal discharge and/or bleeding, and recurrent urinary tract infections. All vaginal and urethral erosions were detected by physical examination and cystoscopy. Symptoms resolved after removal of the eroded sling component. Of the 12 patients with vaginal or urethral erosions, 7 developed recurrent postoperative stress incontinence. CONCLUSIONS: Persistent painful or irritative symptoms after pubovaginal sling placement may be due to urogenital tract erosion, especially if synthetic materials were used. Appropriate evaluation and treatment will result in dramatic symptomatic improvement, although recurrent stress incontinence may occur.

Nephrolithiasis associated with the ketogenic diet.

PURPOSE: The ketogenic diet has been used for treating seizure disorders for more than 70 years. Nephrolithiasis is a known complication of this diet with a reported stone rate as high as 10% but there is sparse literature detailing the nature and treatment of these stones. We report on 4 children with nephrolithiasis on this diet. MATERIALS AND METHODS: We describe stone treatment and analysis as well as metabolic and urine abnormalities in 4 children with nephrolithiasis on the ketogenic diet who presented to our institution. RESULTS: All patients were treated with shock wave lithotripsy, fluid liberalization and oral citrate. One child was ultimately withdrawn from the diet due to persistent stone formation. Analysis revealed 3 calcium and 1 ammonium urate stones. Three patients had hypercalciuria, 2 elevated urinary uric acid and 1 hypocitruria. Serum studies revealed acidosis in 3 cases. CONCLUSIONS: The ketogenic diet induces several metabolic abnormalities that increase the propensity for stone formation. Urologists should be aware of this potential complication. Fluid liberalization and bicitrate are recommended as prophylaxis.

Use of a working channel catheter during flexible ureteroscopic laser lithotripsy.

PURPOSE: We describe a technique which protects the working channel of the flexible ureteroscope from damage caused by the laser fiber during laser lithotripsy. MATERIALS AND METHODS: A 2Fr catheter is placed into the working channel of the flexible ureteroscope. A 200 micro. laser fiber is then advanced through the lumen of the catheter and laser lithotripsy is subsequently performed. RESULTS: The catheter provides additional protection to the working channel sheath during passage and firing of the laser fiber. Deflection of the ureteroscope is not affected with the catheter in place. Movement of the laser fiber is augmented by the catheter when compared to movement of the fiber in the working channel alone. Irrigant flow is diminished with the catheter. CONCLUSIONS: The catheter does not appear to hinder performance of the flexible ureteroscope during laser lithotripsy. A catheter also offers additional protection to the working channel sheath, thereby potentially increasing the durability and working life of the flexible ureteroscope.

Collagen injection for the treatment of incontinence after cystectomy and orthotopic neobladder reconstruction in women.

PURPOSE: We determine the clinical efficacy of endoscopically injected collagen for the treatment of new onset urinary incontinence in women following cystectomy and orthotopic neobladder. MATERIALS AND METHODS: Three women 58 to 74 years old underwent transurethral collagen injection for stress urinary incontinence following cystectomy and orthotopic neobladder. Before cystectomy 2 women denied having any stress urinary incontinence while 1 complained of mild incontinence. Onset of incontinence following cystectomy and neobladder formation ranged from 8 months to 3 years, and average pad use ranged from 3 to 5 per 24-hour period. All patients underwent video urodynamic evaluation before collagen injection. Neobladder capacity was 180 to 400 cc and Valsalva leak point pressures ranged from 30 to 60 cm. water. RESULTS: A total of 6 injections were given, including 3 injections in 1 patient, 2 in 1 and 1 in 1. All 3 women had significant improvement or became dry with initial injection but required repeat injections to maintain improved continence status. At 7 to 8 months after the last injection 1 woman was dry, 1 used 1 or no pad daily and 1 reported no durable change in stress urinary incontinence. CONCLUSIONS: Collagen injection appears to be a successful, minimally invasive treatment for new onset stress urinary incontinence following cystectomy and orthotopic neobladder in women.

Stent placement for the diagnosis of upper tract obstruction.

The aim of this study was to evaluate the effectiveness of ureteral stent placement in diagnosing ureteropelvic junction (UPJ) obstruction in patients with negative or equivocal radiographic/nuclear studies and to assess relief of symptoms following definitive surgical procedures to relieve the obstruction. Patients undergoing ureteral stent placements performed by two attending urologists over an 18-month period were reviewed. All patients with equivocal or negative radiographic evaluations for ureteral obstruction in whom the stent was placed for diagnostic purposes were selected. Preoperative and postoperative information was obtained from the medical record or by telephone interview. Five patients were found who had equivocal radiographic studies along with symptoms of flank pain and who underwent diagnostic stent placement. All patients were female (average age 40 years, range 20-52). All had pain relief following stent placement and, on this basis, underwent an operative procedure to remove the presumed ureteral obstruction. Three underwent Acucise endopyelotomy, one had laparoscopic resection of the right ovarian vein, and one underwent nephrectomy. The average preoperative creatinine level was 0.9 mg/dL (range 0.8-1.0), and the average postoperative creatinine level was 1.0 mg/dL (range 0.9-1.1). All patients had relief of flank pain at a mean of 17 months following the surgical procedure. Relief of pain following stent placement in patients with clinical suspicion of ureteral obstruction portends a favorable outcome from procedures to relieve the presumed obstruction. In unusual cases where ureteral obstruction is suspected despite negative or equivocal radiographic findings, diagnostic stent placement appears to be useful.

Androgen deprivation therapy for prostate cancer results in significant loss of bone density.

OBJECTIVES: Advanced prostate cancer is a frequently diagnosed condition in the aging male population, and many men will ultimately be treated with androgen deprivation therapy (ADT). Long-term consequences of ADT on bone mineral density (BMD) have not been systematically studied. We performed a pilot study to test the hypothesis that ADT in patients with prostate cancer results in the measurable loss of BMD. METHODS: A cross-sectional study of 32 men with prostate cancer who were about to begin ADT or who had been receiving ADT for more than 1 year was conducted. BMD was measured by single and dual energy x-ray absorptiometry in the lumbar spine, hip, and forearm. Linear regression analysis was used to estimate the time necessary to develop significant BMD loss in the spine, hip, and forearm regions. RESULTS: Five (63%) of 8 men who had not received ADT and 21 (88%) of 24 men who had received ADT for more than 1 year fulfilled the BMD criteria for osteopenia or osteoporosis at one or more sites. When BMD was compared at each site, men who received ADT for more than 1 year had significantly lower BMD in the lumbar spine than men who had not started treatment (P<0.05). On the basis of regression analysis, an estimated 48 months of ADT would be necessary to develop BMD criteria for osteopenia in the lumbar spine for a man with average BMD at the initiation of therapy. CONCLUSIONS: Pre-existing osteopenia and osteoporosis were common in men with prostate cancer before initiating ADT. Both ADT and the duration of ADT were significantly associated with the loss of BMD in men with prostate cancer.

Determination of the effective therapeutic dose of intrathecal sufentanil for extracorporeal shock wave lithotripsy.

UNLABELLED: Intrathecal (IT) sufentanil provides effective analgesia for extracorporeal shock wave lithotripsy. However, the optimal dose of sufentanil has not been established. We designed a prospective, randomized, double-blinded study to determine the optimal dose of IT sufentanil. Sixty men were randomized to receive 12.5,15,17.5, or 20 microg of IT sufentanil (n = 15 for each group) via a combined spinal epidural technique. Inadequate analgesia was treated with IV propofol, and the epidural was activated for a pain score greater than 6 on a 10-point verbal analog pain scale. Intraoperative and postoperative visual analog pain scale scores were significantly higher in the 12.5-microg group compared with 20-microg group (3.2 +/- 1.6 vs 1.6 +/- 1.2, P < 0.05, and 1.1 +/- 0.5 vs. 0.5 +/- 0.4, P < 0.05, respectively). The smaller-dosage groups of IT sufentanil required significantly more supplemental boluses of propofol compared with the 20-microg group (67%, 53%, and 40% vs 6%, respectively, P < 0.05). However, pruritus was significantly diminished in the smaller-dosage groups compared with the 20-microg group (55%, 60%, and 67% vs 100%, P < 0.05). The time to discharge was significantly shorter in the 15-microg group compared with the 20-microg group (84 +/- 40 min vs 126 +/- 48 min, P < 0.05). These results suggest that 15 microg of IT sufentanil may be the optimal IT dose for patients undergoing extracorporeal shock wave lithotripsy. IMPLICATIONS: Many anesthetic techniques are used for extracorporeal shock wave lithotripsy (ESWL). We have previously shown that intrathecal sufentanil was effective for ESWL, but was associated with a high incidence of itching. We tested 60 patients in four spinal sufentanil dose groups and found that doses of 15 and 17.5 microg provided the most effective analgesia with the fewest side effects for ESWL, with only mild itching.