Laparoscopic donor nephrectomy - safety in a small-volume transplant center.

INTRODUCTION: Laparoscopy is a standard surgical option for live donor nephrectomy (LDN) at the majority of transplant centers. Equivalent graft survival with shorter convalescence has been reported by several large volume centers. With the arrival of an experienced laparoscopic surgeon in 2002, we began to offer laparoscopic LDN at our institution. We report our experience as a large volume laparoscopic surgery program but a low volume transplant center. METHODS: A retrospective review of the previous 34 LDN (17 open, 17 laparoscopic) performed at the University of Missouri were included. A single laparoscopic surgeon performed all laparoscopic procedures. Hand assisted laparoscopy was performed in 15 and standard laparoscopy with a pfannenstiel incision in two. Open procedures were performed through anterior subcostal or flank incision. A single surgeon performed all open procedures. RESULTS: There was no statistical difference in age, body mass index or American Society of Anesthesiologies Score between the two groups. Mean operative time, estimated blood loss and hospital stay were 229 minutes, 324 cc and 2.2 days respectively in the laparoscopic group compared to 202 minutes, 440 cc and five days for the open group. Average warm ischemia time was 179 seconds. Recipient creatinine for the two groups at one week, one month and one year was not statistically significantly different. Each group had one graft loss due to medication noncompliance. CONCLUSION: For small transplant centers with an advanced laparoscopic program, laparoscopic LDN is a safe procedure with comparable outcomes to major transplant centers.

Retrograde ureteroscopy for renal stones larger than 2.5 cm.

INTRODUCTION AND OBJECTIVES: Because of the advances in endoscopic technology, retrograde flexible ureteroscopy (URS) is being applied to larger renal stone burdens. For stones greater than 2.5 cm, percutaneous nephrolithotomy has long been considered the standard of care. We have encountered a growing population of patients who desire a less invasive, less disruptive approach to large renal stones. We present our experience with retrograde ureteroscopic management of renal stones larger than 2.5 cm. METHODS: Twenty-two patients between October 2004 and June 2008 underwent retrograde flexible URS with holmium laser lithotripsy. Each patient underwent retrograde URS using the Storz Flex-X and a ureteral access sheath. Patients were evaluated for number of procedures, stone clearance rates, and hospital admissions. Postoperative kidney, ureter, and bladder radiograph was used to determine stone-free rates. RESULTS: Mean stone size was 3.0 cm. The average number of procedures was 1.82 with 5 patients requiring one, 14 requiring two, and 1 requiring three procedures. There were two failures who went on to have percutaneous nephrolithotomy, both of whom had significant lower pole stone burden. Overall stone-free rate was 90.9%. There were three overnight admissions for stent pain, and one 3-day admission for bacteremia in a patient who was noncompliant with preoperative antibiotics. CONCLUSIONS: Planned staged URS is a viable option for the treatment of renal stones larger than 2.5 cm with excellent stone-free results. Significant lower pole stone burden is a limiting factor.

MR determination of glomerular filtration rate in subjects with solitary kidneys in comparison to clinical standards of renal function: feasibility and preliminary report.

This study was conducted to demonstrate the feasibility of quantifying single kidney glomerular filtration rate (skGFR) by magnetic resonance (MR) by comparison to the clinical estimates of GFR in volunteer subjects with a single kidney. Seven IRB-approved subjects with a solitary kidney, stable serum creatinine (SCr) and a 24 h creatinine clearance (CrCl) volunteered to undergo an MR examination that determined renal extraction fraction (EF) with a breathhold inversion recovery echo planar pulse sequence and renal blood flow with a velocity encoded phase imaging sequence. The product of EF and blood flow determines GFR. These values were compared with the 24 h CrCl, estimated GFR by the modification of diet in renal disease (MDRD) regression analysis and the Cockroft-Gault (CG) determination of CrCl. The mean and standard deviation of differences between the MR GFR, MDRD and CG vs the 24 h CrCl were 12.3+/-35.7, -8.9+/-18.5 and 1.2+/-19.6, respectively. The Student t-test showed that none of the mean differences were statistically significant between techniques. This clinical investigation shows that MR can be used for skGFR determination in human subjects with comparable values to those derived from clinically used serum-based GFR estimation techniques.

Laparoscopy versus dorsal lumbotomy for ureteropelvic junction obstruction repair.

PURPOSE: Laparoscopic pyeloplasty offers similar success rates compared to open surgery. However, the advanced laparoscopic skills required may limit its widespread application. In select patients the dorsal lumbotomy approach can provide similar postoperative advantages to minimally invasive surgery. We analyze the perioperative management of laparoscopy vs dorsal lumbotomy for the repair of ureteropelvic junction obstruction. MATERIALS AND METHODS: In a retrospective review 13 patients who underwent dorsal lumbotomy pyeloplasty were compared to 19 patients who underwent laparoscopic pyeloplasty between 1998 and 2003. Preoperative confirmation of obstruction was obtained through excretory urogram or renal Lasix scan. All 13 patients undergoing dorsal lumbotomy had a dismembered pyeloplasty. Of the 19 laparoscopic cases 16 had a dismembered pyeloplasty and 3 had a Fenger procedure. Average followup was 12 months for the open group and 13.3 months for the laparoscopic group. Postoperative results were evaluated with excretory urogram or renal Lasix scan as well as subjective outcomes by the patients. RESULTS: Operative time was slightly longer for the laparoscopy group at 231 minutes vs 200 minutes. Estimated blood loss and postoperative morphine requirements were also similar. Hospital stay was 3.3 days for the dorsal lumbotomy group compared to 2.4 for the laparoscopy group. The overall success rate for the laparoscopic group was 94.7% compared to 100% for the dorsal lumbotomy group. Each group had 1 complication, paresthesia of anterior/medial thigh that resolved by 6 months. CONCLUSIONS: Our preliminary results show that a dismembered dorsal lumbotomy pyeloplasty is comparable to laparoscopic dismembered pyeloplasty with regard to intraoperative and postoperative hospital course.

Hand-assisted laparoscopic approach to renal harvest for autotransplantation.

PURPOSE: To describe a laparoscopic hand-assisted approach to renal autotransplantation that allows both harvest and transplant through the same incision. PATIENTS AND METHODS: Three patients underwent renal autotransplantation from May 2003 to April 2004, two for loin pain-hematuria syndrome and one for severe ureteral-stricture disease. Two patients underwent autotransplantation on the left and one on the right. Hand-assisted laparoscopy was planned such that inferomedial extension of the hand-port incision would provide adequate exposure of the iliac vessels for autotransplantation. RESULTS: The average operative time was 240 minutes, the warm ischemia time was 2 minutes 43 seconds, and the hospital stay was 3 days. All three patients had successful graft function by postoperative renal scan with a mean follow-up of 7.1 months. CONCLUSION: Hand-assisted laparoscopic renal harvest for autotransplantation can be completed with placement of the hand port such that transplantation can be accomplished through the same incision. As many of these patients have had multiple prior retroperitoneal operations, the intracorporeal hand can greatly facilitate these potentially difficult dissections with no added morbidity.

Incisional hernia following hand-assisted laparoscopic surgery for renal cell cancer.

OBJECTIVES: For renal cell cancer, the hand-assisted laparoscopic approach provides several advantages while maintaining equal advantages with regards to patient recovery. We offer our experience with laparoscopic hand-assisted radical nephrectomy and the incidence of ventral wall hernia. METHODS: Between February 1999 and July 2002, we performed 50 laparoscopic hand-assisted radical nephrectomies. A midline or a muscle splitting right lower quadrant incision was used depending on the side of the tumor. Hand-port incisions were all between 7 cm and 8 cm and closed with #1 polydioxanone sulfate suture in a running fashion. Three (6%) patients developed hand-port incisional hernias. All hernias occurred in midline hand-port sites. The average body weight of those who developed an incisional hernia was 137 kg. Although the cause of incisional hernia is multifactorial, we believe that obesity plays a significant role. The technical limitations involved in closing a short, deep ventral incision combined with the earlier return to activity of laparoscopy patients put this patient population at significant risk. CONCLUSION: We now perform an interrupted closure with nonabsorbable suture for the hand-assist incision and limited activity for 4 weeks to 6 weeks post procedure in high-risk patients. We have had no further wound hernias since adopting these changes.

A review of surgical simulation with attention to validation methodology.

The use of simulation technology for teaching and evaluating surgical skills has gained considerable attention in recent years. This is driven by interest in quality of care, concerns over increasing operative complexity, constraints on the use of animal models, limited available patient material, medicolegal pressures, and fiscal mandates for cost-effective performance. Traditional mechanical models are yielding to techniques dependent on electronic technology, including virtual reality. Data to support the validity of simulation techniques for surgical training, assessment, and certification represent only a fraction of the literature available on the subject. Literature searches were conducted in MEDLINE and ERIC, covering the period from 1966 to the present. The electronic and bioengineering literature was not surveyed due to the extensive literature on technology development, distinct from assessment of context specific validity. The search results and the bibliographies of key review articles were examined to identify articles that contained original data, measured performance between cohorts, defined performance measures, and described a standard against which performance was compared. Most of the literature pertaining to simulation techniques for surgical training has been published within the past 5 years and consist of review, opinion, and feasibility articles. There is an emerging body of evidence to establish the validity of simulation techniques for assessing surgical skills. Further refinement of simulation techniques, identification of specific performance measures, longitudinal evaluations, and comparison to practice outcomes are still needed to establish the validity and the value of surgical simulation for teaching and assessing surgical skills prior to considering implementation for certification purposes.

An assessment of the use of a continent catheterizable stoma in female tetraplegics.

OBJECTIVES: To evaluate the success of a continent catheterizable stoma in females with cervical spinal cord injury which resulted in neurogenic bladder dysfunction, the management of which may require clean intermittent catheterization despite altered hand function. PATIENTS AND METHODS: Six female tetraplegic patients with a lesion at C7 or above (age range 12-22 years) had a continent catheterizable abdominal stoma formed as part of their bladder management. As an objective measure of effectiveness, the time to complete catheterization was assessed before and after surgery. A quality-of-life survey at a mean (range) of 44 (6-90) months was also evaluated. RESULTS: All six patients can catheterize while in their wheelchair. The mean (range) time required for catheterization decreased from 27 (10-40) to 7.8 (1-15) min after surgery. All six reported a significant improvement in continence, body image, independence, convenience, time saving and satisfaction. CONCLUSION: Constructing a continent catheterizable stoma is a valuable option in selected tetraplegic patients.

Hand-assisted laparoscopy for multiple organ removal.

Simultaneous removal of multiple organs is a situation seldom encountered by the urologist but may be needed in patients with adult polycystic kidney disease or malignancies or infectious processes involving more than one organ. Historically, open surgery has been considered necessary to gain adequate exposure. However, hand-assisted laparoscopic surgery is suitable for many of these patients. The hand-port and trocar positions are chosen according to the laparoscopic experience of the surgeon and depend on whether an ambidextrous or nondominant-hand procedure is planned. Several techniques are described, with a focus on bilateral nephrectomy.

Intestinal Oxalobacter formigenes colonization in calcium oxalate stone formers and its relation to urinary oxalate.

BACKGROUND AND PURPOSE: Oxalobacter formigenes is an anaerobic commensal colonic bacterium capable of degrading oxalate through the enzyme oxalyl-CoA decarboxylase. It has been theorized that individuals who lack this bacterium have higher intestinal oxalate absorption, leading to a higher urinary oxalate concentration and an increased risk of calcium oxalate urolithiasis. We performed a prospective, controlled study to evaluate O. formigenes colonization in calcium oxalate stone formers and to correlate colonization with urinary oxalate and other standard urinary stone risk factors. PATIENTS AND METHODS: Thirty-five first-time calcium oxalate stone formers were compared with 10 control subjects having no history of urolithiasis and a normal renal ultrasound scan. All subjects underwent standard metabolic testing by submitting serum and 24-hour urine specimens. In addition, all subjects submitted stool samples for culture and detection of O. formigenes by Xentr(ix) O. formigenes Monitor. RESULTS: Intestinal Oxalobacter was detected in only 26% of the stone formers compared with 60% of the controls (p < 0.05). Overall, the average urinary oxalate excretion by the two groups was similar (38.6 mg/day v 40.8 mg/day). Among stone formers, however, there were statistically higher urinary oxalate concentrations in O. formigenes-negative patients compared with those testing positive (41.7 mg/day v 29.4 mg/day) (p = 0.03). Furthermore, all 10 stone formers with hyperoxaluria (>44 mg/day) tested negative for O. formigenes (p < 0.05). CONCLUSIONS: Calcium oxalate stone formers have a low rate of colonization with O. formigenes. Among stone formers, absence of intestinal Oxalobacter correlates with higher urinary oxalate concentration and an increased risk of hyperoxaluria. Introduction of the Oxalobacter bacterium or an analog of its enzyme oxalyl-CoA decarboxylase into the intestinal tract may be a treatment for calcium oxalate stone disease.

Correlation of ureteral stone measurements by CT and plain film radiography: utility of the KUB.

BACKGROUND AND PURPOSE: The practice of utilizing helical CT to evaluate patients suspected of renal colic is increasing. Little is known about the accuracy of CT in estimating stone size or the utility of an accompanying plain abdominal radiograph (KUB film). The purpose of our study was to compare ureteral stone size estimation by helical CT and plain film and determine whether a KUB film provides additional information useful in patient management. PATIENTS AND METHODS: Thirty consecutive patients (17 male, 13 female) having both a helical CT and a KUB study for evaluation of renal colic secondary to ureteral calculi comprised the study population. Calculus number, location, and dimensions were determined from these images. Stone dimensions were measured using electronic calipers on a picture archiving and communications system. Information found by KUB and CT was compared, and both sets of stone measurements were correlated with patient outcome. RESULTS: The mean maximal stone transverse diameter and length were similar on CT and plain film: 5.8 mm v 5.8 mm and 9.5 mm v 8.9 mm, respectively (P = 0.57 and 0.29, respectively). The mean anteroposterior stone diameter on CT of 6.8 mm was statistically greater than the transverse diameter as measured by both CT and KUB, which were 5.8 mm and 5.8 mm (P = 0.0002 and 0.0007, respectively). Eleven patients spontaneously passed their stones, while 19 patients required intervention. Patient outcome, as predicted by transverse stone width, was similar for CT and KUB data. CONCLUSIONS: The management of patients with ureteral calculi relies on estimated stone size and the stone's potential for spontaneous passage. Stone dimensions estimated by CT are similar to the size determined by plain film radiography. Although plain film radiography does not provide information on stone dimensions beyond that obtained with CT, it does reveal precise stone location and radiolucency, data helpful in following and treating patients.

Extraperitoneal laparoscopy-assisted percutaneous nephrolithotomy in a left pelvic kidney.

Treatment of urolithiasis within a pelvic kidney presents a technical challenge. We report an extraperitoneal laparoscopy-assisted percutaneous approach to access the lower-pole calix of a pelvic kidney for percutaneous nephrolithotomy.

Renal intrapelvic pressure during percutaneous nephrolithotomy and its correlation with the development of postoperative fever.

PURPOSE: Systemic absorption of irrigation fluid containing bacteria or endotoxin may lead to fever and urosepsis after percutaneous nephrolithotomy. Although to our knowledge the exact method of absorption is undefined, intrapelvic pressure greater than 30 mm. Hg has been shown to result in pyelovenous-lymphatic backflow. We measured intrapelvic pressure during percutaneous nephrolithotomy and correlated pressure with postoperative fever and operative technique. MATERIALS AND METHODS: Intrarenal pressure was measured with a transurethral 7Fr ureteral occlusion balloon catheter and a urodynamic system during percutaneous renal access, rigid and flexible nephroscopy, and intracorporeal lithotripsy. Postoperative fever was correlated with elevated intrarenal pressure, stone type and surgical technique. RESULTS: Enrolled in this study were 18 women and 13 men. Pressure greater than 30 mm. Hg was recorded in 8 patients (26%). Elevated pressure occurred under 2 conditions, namely incomplete positioning of the nephroscopy sheath within the collecting system and endoscopy through a narrow infundibulum. In 13 cases (42%) a fever of 38C or greater developed postoperatively. Elevated pressure did not correlate with fever. However, of those undergoing percutaneous nephrolithotomy for the removal of infection versus noninfection stones 64% and 24%, respectively, had fever postoperatively. CONCLUSIONS: Renal intrapelvic pressure generally remains low during percutaneous nephrolithotomy. Elevated pressure was associated with incomplete nephroscopy sheath positioning within the collecting system and endoscopy through an infundibular narrowing. There was no association of renal pressure greater than 30 mm. Hg with fever but postoperative fever and percutaneous nephrolithotomy done for infection related stones correlated significantly.