Laparoscopic versus open nephrectomy in 210 consecutive patients: outcomes, cost, and changes in practice patterns.

BACKGROUND: Initially slow to gain widespread acceptance within the urological community, laparoscopic nephrectomy is now becoming the standard of care in many centers. Our institution has seen a dramatic transformation in practice patterns and patient outcomes in the 2 years following the introduction of laparoscopic nephrectomy. We compare the experience with laparoscopic and open nephrectomy within a single medical center. METHODS: Data were collected for all patients undergoing elective nephrectomy (live donor, radical, simple, partial, and nephroureterectomy) between August 1998 and September 2002. Data were analyzed by Wilcoxon rank sum, chi-square, and Fisher's exact test. A p-value <0.05 was considered significant. RESULTS: Of the patients, 92 underwent open nephrectomy, and 118 were treated laparoscopically (87 hand-assisted laparoscopic nephrectomy, 31 totally laparoscopic). There was one conversion (0.8%). Patient demographics and indications for surgery were equivalent for both groups. Mean operative time for laparoscopic nephrectomy (230 min) was longer than for open (187 min, p = 0.0001). Blood loss (97 ml vs 216 ml, p = 0.0001), length of stay (3.9 days vs 5.9 days, p = 0.0001), perioperative morbidity (14% vs 31%, p = 0.01), and wound complications (6.8% vs 27.1%, p = 0.0001) were all significantly less for laparoscopic nephrectomy. For live donors, time to convalescence was less (12 days vs 33 days, p = 0.02), but hospital charges were more for patients treated laparoscopically (19,007 dollars vs 13,581 dollars, p = 0.0001). CONCLUSIONS: Laparoscopic nephrectomy results in less blood loss, fewer hospital days, fewer complications, and more rapid recovery than open surgery. We believe that these benefits outweigh the higher hospital charges associated with the laparoscopic approach.

Radially expanding single-step nephrostomy tract dilator.

OBJECTIVES: To compare the radial and axial forces produced by balloon, Amplatz, and radially expanding single-step nephrostomy (RESN) systems and report our initial clinical results using the new RESN device. Balloon, Amplatz, and Alken dilators are commonly used to establish nephrostomy tracts in percutaneous surgery. They require multiple steps, with the potential for kinking and displacement of the working guidewire. In contrast, the new RESN tract dilator expands a unique sleeve conduit and places an Amplatz-like sheath in a single step with less dependence on a guidewire for dilation. METHODS: An experimental model was designed using a perforated silicon disc with a 10F central opening to measure the axial force transmission as 30F balloon, Amplatz, and RESN systems were inserted through the silicon discs. We also report our first 9 patients who underwent percutaneous dilation with the RESN system. RESULTS: Thirty French expansion was achieved with each dilator tested. Substantially lower axial forces were transmitted with the RESN device compared with the balloon and Amplatz dilators (5.2 versus 13.1 and 19.2 lb, respectively, P <0.001). Intraoperatively, all 9 patients were successfully dilated, and the kidney was relatively stationary as imaged with fluoroscopy. One patient with multiple prior renal procedures was successfully dilated with RESN system after failed attempts with balloon dilation. CONCLUSIONS: The RESN dilator is a rapid, single-step access system successfully used in our first 9 patients. Intraluminal sleeve dilation eliminates guidewire dependence for maintaining access, limits renal displacement, and facilitates appropriate vector force for percutaneous dilation.

Percutaneous access techniques in renal surgery.

Percutaneous renal surgery is continually being improved, refined, and embraced by urologists worldwide. With the advent of extracorporeal shock wave lithotripsy (ESWL), many percutaneous techniques have been abandoned or forgotten. We are learning, however, that ESWL is not a panacea for all urinary calculi and different methods need to be used to obtain stone-free patients. We discuss the history, anatomy, techniques, and specific problems and complications ofpercutaneous renal surgery specifically relating to renal stone disease.

Laparoscopy for the acute abdomen in the postoperative urologic patient.

OBJECTIVES: Exploratory laparotomy offers the greatest diagnostic accuracy of intra-abdominal pathologic processes, but can be associated with significant morbidity. Laparoscopy provides diagnostic capabilities equivalent to that of open exploration, but with potentially less morbidity. We present 3 cases in which laparoscopy was used to diagnose and manage urologic patients with an acute abdomen in a postoperative period. METHODS: Three patients underwent laparoscopy between 1 and 14 days postoperatively for an acute abdomen (fever, elevated white blood cell count, and peritoneal signs). The initial procedures included a pubovaginal sling repair with fascia lata, endoscopic placement of a percutaneous gastrostomy tube, and a laparoscopic ureterolithotomy for a distal stone. RESULTS: In each of the 3 patients laparoscopy revealed misplacement or malfunction of a previously placed tube. In all cases, the patient was managed laparoscopically without the need for laparotomy. CONCLUSIONS: These cases demonstrate the feasibility of laparoscopy to provide diagnostic and therapeutic solutions to postoperative urologic patients presenting with an acute abdomen.

Incidence of stool guaiac conversion following extracorporeal shock wave lithotripsy.

OBJECTIVES: To study, in a prospective fashion, acute traumatic effects on the gastrointestinal tract of patients treated by extracorporeal shock wave lithotripsy (ESWL). METHODS: Stool samples from each of 54 patients were tested before and after ESWL for conversion to hemoccult positive. A minimum of one negative pre-ESWL stool guaiac test was required for inclusion into the study. A minimum of two stool guaiac tests were done after ESWL to verify negativity. Patients who converted to a positive hemoccult test after ESWL were then evaluated by colonoscopy for the source of bleeding. RESULTS: Fifty patients completed the study. A single patient (2.0%) converted to a positive post-ESWL hemoccult test and was evaluated with colonoscopy. This patient was found to have two benign adenomatous polyps in the sigmoid and descending colon after treatment for a left renal pelvis calculus. An additional patient with a slightly positive post-ESWL conversion refused further evaluation. The overall post-ESWL conversion rate to guaiac positive, therefore, was less than 4% (2 of 51 patients). CONCLUSIONS: There is no evidence of significant trauma or detectable bleeding in the normal gastrointestinal tract caused by ESWL as measured by postprocedure stool guaiac testing. Guaiac testing of the stool after ESWL may unmask pre-existing gastrointestinal disease. Therefore a positive guaiac test after ESWL warrants further evaluation. This study reaffirms that ESWL is a safe, minimally invasive technique for the treatment of urolithiasis, without significant adverse side effects on the gastrointestinal tract.

Clinical correlates of the gross, radiographic, and histologic features of urinary matrix calculi.

We present five patients with urinary matrix calculi, which, in contrast to the normally brittle calcigerous calculi, are soft, pliable, and amorphous. Common clinical features include a history of calcigerous stone disease, renal surgery, urinary obstruction or stasis, and chronic infection with Proteus species or coliforms. The diagnosis is usually made at surgery, but certain preoperative radiographic findings may be suggestive. Matrix calculi are radiolucent on plain abdominal films, although their appearance on nonenhanced CT scans is similar to that of calcigerous calculi despite their small mineral content. Extracorporeal shockwave lithotripsy is ineffective; open or percutaneous techniques are necessary. Histologic inspection reveals laminar concentric rings of organized matrix with an orderly, layered deposition of minerals. Histochemical investigation can provide insight into the possible sequence of events in normal calculogenesis. The successful management of urinary matrix calculi depends on a high index of suspicion and a thorough knowledge of their clinicopathologic features.

Urologic applications at a community zoo.

The genitourinary system is a common source of disease in many animal species as well as humans, and the practice of comparative endourology is possible because of advances in the past decade in minimally invasive human surgery. Zoo veterinarians may have limited formal urologic training, and increasingly limited public funding resources now leave most community zoos without specialized endourologic equipment or expertise. Urologists may offer or be called on to assist in the diagnosis and management of often rare and valuable species, providing services and expertise previously limited to humans. Such cases may provide intellectual and technical challenges beyond those seen in clinical practice, while applying the same basic universal urologic principles. We describe a cooperative approach to the management of animal urologic disorders based on a 5-year experience as consultants to the San Francisco Zoo and encourage an interdisciplinary approach between urologists and their local zoos where this may be useful in the preservation and maintenance of these valuable and important public resources.

Urolithoscintigraphy: preliminary report of a new imaging modality for urolithiasis.

We investigated the use of bisphosphonates, analogs of pyrophosphate that bind to mineralized tissue, to image renal calculi in vivo. Twenty stone-bearing kidneys in 15 patients without urinary obstruction were studied. 99mTechnetium-methylene diphosphonate was injected intravenously followed by 20 mg of furosemide 4 hours later, and images were obtained by gamma counter for 30 minutes. Areas of increased uptake corresponded with the sites of calculi, and even small or radiolucent calculi were easily seen. Counts in the region of each kidney, the L4 vertebral body, and a background area were combined to calculate a scintigram index (SI) for each kidney. The mean SI of the stone-bearing kidneys was 4.8 +/- 3.5 v 1.3 +/- 0.4 for the normal kidneys. There was correlation of the SI with stone composition and size but not with radiographic density. After correction for size, the SI of stone-bearing kidneys remained significantly higher than the SI of normal kidneys, but the differences between calculi of different compositions were diminished. Nonetheless, high SI values were associated with soft types of calculi and low values with hard types. Future investigations will reveal if this association is constant and if there is any relation between bisphosphonate uptake and response to lithotripsy. The sensitivity of urolithoscintigraphy to image small or radiolucent calculi may make it an effective technique for the assessment of residual fragments after lithotripsy.

Laparoscopic marsupialization of a simple renal cyst.

An 8 cm. symptomatic simple renal cyst, recurrent despite previous aspiration and injection of sclerosing agents, was marsupialized using laparoscopic techniques. No complications occurred and followup by ultrasonography confirmed resolution of the lesion. We suggest that laparoscopic management of symptomatic simple renal cysts may be an attractive alternative to open surgical techniques.

Long-term follow-up of ventriculoureteral shunts for treatment of hydrocephalus.

Surgical relief of hydrocephalus is achieved mainly with ventriculoperitoneal or ventriculoatrial shunting. In some patients, frequent reoperations are required because of infection, obstruction, or other complications, thus subjecting them to excessive operative morbidity and risk of neurological damage. One option that has been rarely addressed in recent years is drainage of cerebral spinal fluid into the urinary tract by way of a ventriculoureteral shunt. Patients who have endured multiple revisions of standard cerebral spinal fluid shunts may benefit from a relatively lower frequency of reoperation following ventriculoureteral shunting. There are several complications peculiar to this procedure, however, including ascending infection from the bladder, proximal shunt migration out of the ureter or distal migration into the bladder, failed urinary diversion, and electrolyte disturbances associated with volume depletion. Long-term follow-up of patients with ventriculoureteral shunts has not been reported. We describe the course of 4 patients successfully treated with ventriculoureteral shunts for an average of more than five years per patient. Although all eventually required reoperation, the frequency of reoperation with the ventriculoureteral shunts was markedly lower than with the standard shunts in these patients. Ventriculoureteral shunting should be considered for cerebral spinal fluid drainage in selected patients with multiple failures of standard shunts, provided the bladder is a low pressure reservoir with no urine infection.

Percutaneous suprapubic cystostomy.

Suprapubic urinary diversion for the management of lesions of the bladder outlet or urethra has been facilitated by the advent of percutaneous access techniques. Prior to percutaneous endourologic techniques, an open surgical approach was necessary when the transurethral route was impassable. A variety of percutaneous suprapubic cystostomy techniques have evolved in recent years. These have been based on several different access principles and offer the urologist a number of options. Selection of an individual technique is usually a matter of preference and familiarity with a particular manufacturer's product. The list of indications for such an approach is diverse and continues to expand.

The effects of ileocystoplasty on the development of renal failure in a rat model 5/6 nephrectomy.

We examined the effects of ileocystoplasty on renal function and bone mineral content in 160 juvenile male Wistar-Furth rats with and without renal insufficiency induced by 5/6 nephrectomy. At intervals up to 20 weeks blood, bone and kidney samples were obtained with the animals under anesthesia and then they were sacrificed. Serum parameters of renal function and calcium metabolism were measured. Samples of bone were analyzed for calcium, magnesium and phosphorus content. At 20 weeks after 5/6 nephrectomy renal function was decreased by approximately half. The decrease in renal function and the changes in renal histology were identical in animals with and without ileocystoplasty. Bone mineral content in the animals with renal insufficiency with or without ileocystoplasty was not different from sham operated animals or from animals with an ileocystoplasty and normal renal function. These studies demonstrate that ileocystoplasty per se does not hasten the progression to renal failure or produce bone demineralization in rats having moderate renal insufficiency.

Fungal bezoars of the upper urinary tract.

We report our experience with 6 cases of upper tract fungal bezoars involving 9 renal units-3 bilateral aspergillomas and 3 Candida bezoars. The Aspergillus bezoars were notably more morbid: 2 patients required nephrectomy after failure of medical therapy, whereas the 3 unilateral Candida bezoars all resolved with medical therapy and endourological access. In 1 patient whose aspergilloma was resistant to amphotericin B the investigational drug itraconazole proved effective. These opportunistic infections, seen increasingly in immunocompromised patients, can present a difficult management problem. A combined approach is necessary, including medical therapy with topical and systemic antifungal agents, and endourological access for extraction, lavage and debulking.