Preoperative and intraoperative factors predictive of complications and stricture recurrence following multiple urethroplasty techniques

Objectives

To investigate factors predictive of postoperative recurrence and complications in patients undergoing urethroplasty for stricture repair at a single center.

Patients and methods

We retrospectively reviewed the records of 108 men who underwent urethroplasty for urethral stricture disease (USD) at a single center from 2016 to 2020. Demographic data, comorbidities, stricture history including etiology and prior treatments, patient‐reported symptoms, and outcomes data were collected for analysis. Data were analyzed in aggregate, then, stratified by type of urethroplasty performed. Descriptive statistics, univariate analysis, multivariate logistic regression, and intergroup comparisons were completed using STATA, with an alpha value of 0.05 and a confidence interval of 95%.

Results

The median age of our patients was 58 years (interquartile range: 42‐69; range: 29‐83), with a median stricture length of 2.0 cm (interquartile range: 1.0‐4.5; range: 0.5‐10). The most common stricture etiology was iatrogenic (n = 33, 31%) and the most common urethroplasty was anterior anastomotic urethroplasty (n = 38, 35%), followed by buccal mucosal graft (BMG) urethroplasty (n = 35, 32%). Twenty‐four patients (22%) had stricture recurrence. Within the aggregate data, recurrence was significantly predicted by obesity (BMI > 30) (Odds Ratio [OR] 3.2, 95% Confidence Interval [CI]: 1.06‐10), and the presence of postoperative complications (OR 6.3, CI: 1.9‐21). The presence of any postoperative complications within 90 days was significantly predicted by stricture length ≥ 5 cm (OR 3.5, CI 1.09‐12) and recurrence (OR 6.0, CI 1.7‐21).

Conclusion

Despite serving as the most definitive treatment for urethral stricture management, stricture recurrence and postoperative complications are not uncommon after urethroplasty. Obesity and stricture length negatively impact outcomes while a penile stricture location is associated with a lower recurrence rate, though this is not statistically significant.

Surface modification to improve in vitro attachment and proliferation of human urinary tract cells

OBJECTIVE

To evaluate the attachment and proliferation of cultured human urinary tract cells to culture plates surface-modified by photochemical immobilization of extracellular matrix (ECM) proteins.

MATERIALS AND METHODS

Human uroepithelial (UEC) and smooth muscle (SMC) cells were harvested from ureter and expanded in culture; 24-well culture plates surface-modified by photochemical covalent immobilization of ECM proteins were then seeded with UEC or SMC. To characterize cellular attachment, cells were incubated on surface-modified plates for 30 and 90 min. For proliferation assays the cells were incubated for 3-12 days. Standard tissue culture plates with no surface modification and sham-modified plates served as controls. Differential attachment and proliferation on the various surfaces were assessed using analysis of variance with Fisher's posthoc test for multiple comparisons.

RESULTS

Attachment at 30 and 90 min of both UEC and SMC on plates surface-modified with ECM proteins was significantly greater than in control plates. Surface-modification with collagen resulted in significantly greater cellular attachment than with either laminin or fibronectin. UEC proliferation was also significantly greater than in control plates by surface-modification with collagen and fibronectin, but not with laminin. SMC proliferation was significantly better after surface modification than on sham- modified plates, but was no better than standard plates.

CONCLUSIONS

Covalent photochemical immobilization of ECM proteins to potential growth surfaces enhances the attachment of cultured UEC and SMC and the proliferation of UEC. This technique might be useful in modifying surface properties of synthetic polymer-based materials in a controlled and defined manner, giving them the capacity to promote and sustain the growth of urinary tract cells. This may lead to development of alternative methods of tissue engineering in the urinary tract.

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.

A canine model to assess the biochemical stress response to laparoscopic and open surgery

PURPOSE

To develop an animal model to assess the stress response to open and laparoscopic surgery. Such a model would allow objective physiologic assessment of the putative benefits of laparoscopy and provide a framework in which to compare modifications in operative and anesthetic technique that might decrease the stress of surgery.

MATERIALS AND METHODS

Mongrel dogs underwent laparoscopic (N = 12) or open surgical (N = 12) left nephrectomy. In 11 control animals, after induction of anesthesia and line placement, the animal underwent either no intervention (open surgery sham; N = 6) or pneumoperitoneum only (laparoscopic sham; N = 5). Serum glucose and cortisol were measured preoperatively, at skin closure, and at 4, 8, and 24 hours postoperatively. Values at each time point were compared in the laparoscopic and open surgical nephrectomy groups and in each of the two nephrectomy groups and their respective shams.

RESULTS

Compared with baseline, there was a sharp rise in serum cortisol at the time of skin closure, with a gradual decline to baseline values by 24 hours, in all experimental animals. Significantly lower serum cortisol concentrations were seen at 4 and 8 hours postoperatively in the laparoscopic group than in the open surgery group. Cortisol was significantly higher in the open group than in the sham-open group at all time points, whereas cortisol was greater in the laparoscopic group than in the pneumoperitoneum-only group only at the 4-hour time point. No differences were seen in serum glucose between groups.

CONCLUSIONS

The serum cortisol concentration appears to be a good measure of surgical stress in the canine model. The rapid decline in serum cortisol after laparoscopy compared with open surgery may indicate a lesser degree, or quicker resolution, of surgical stress in the former. Furthermore, the similarity in cortisol curves between laparoscopy and pneumoperitoneum only suggests that surgical stress in laparoscopic surgery may be attributable mainly to the effects of pneumoperitoneum.

Prospective randomized trial comparing shock wave lithotripsy and ureteroscopy for management of distal ureteral calculi

PURPOSE

We compared the efficacy of shock wave lithotripsy and ureteroscopy for treatment of distal ureteral calculi.

MATERIALS AND METHODS

A total of 64 patients with solitary, radiopaque distal ureteral calculi 15 mm. or less in largest diameter were randomized to treatment with shock wave lithotripsy (32) using an HM3 lithotriptor (Dornier MedTech, Kennesaw, Georgia) or ureteroscopy (32). Patient and stone characteristics, treatment parameters, clinical outcomes, patient satisfaction and cost were assessed for each group.

RESULTS

The 2 groups were comparable in regard to patient age, sex, body mass index, stone size, degree of hydronephrosis and time to treatment. Procedural and operating room times were statistically significantly shorter for the shock wave lithotripsy compared to the ureteroscopy group (34 and 72 versus 65 and 97 minutes, respectively). In addition, 94% of patients who underwent shock wave lithotripsy versus 75% who underwent ureteroscopy were discharged home the day of procedure. At a mean followup of 21 and 24 days for shock wave lithotripsy and ureteroscopy, respectively, 91% of patients in each group had undergone imaging with a plain abdominal radiograph, and all studies showed resolution of the target stone. Minor complications occurred in 9% and 25% of the shock wave lithotripsy and ureteroscopy groups, respectively (p value was not significant). No ureteral perforation or stricture occurred in the ureteroscopy group. Postoperative flank pain and dysuria were more severe in the ureteroscopy than shock wave lithotripsy group, although the differences were not statistically significant. Patient satisfaction was high, including 94% for shock wave lithotripsy and 87% for ureteroscopy (p value not significant). Cost favored ureteroscopy by $1,255 if outpatient treatment for both modalities was assumed.

CONCLUSIONS

Ureteroscopy and shock wave lithotripsy were associated with high success and low complication rates. However, shock wave lithotripsy required significantly less operating time, was more often performed on an outpatient basis, and showed a trend towards less flank pain and dysuria, fewer complications and quicker convalescence. Patient satisfaction was uniformly high in both groups. Although ureteroscopy and shock wave lithotripsy are highly effective for treatment of distal ureteral stones, we believe that HM3 shock wave lithotripsy, albeit slightly more costly, is preferable to manipulation with ureteroscopy since it is equally efficacious, more efficient and less morbid.

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.

IL (interleukin)-1alpha promotes nuclear factor-kappaB and AP-1-induced IL-8 expression, cell survival, and proliferation in head and neck squamous cell carcinomas

Interleukin 1alpha (IL-1alpha) is an important regulatory cytokine, the release of which after an injury can induce activation of transcription factors nuclear factor (NF)kappaB and activator protein (AP-1), which promote expression of genes involved in cell survival, proliferation, and angiogenesis. IL-1alpha is expressed autonomously by head and neck squamous cell carcinomas (HNSCCs) and a variety of other cancers, raising the possibility that IL-1alpha may serve as an autocrine factor that stimulates the activation of prosurvival transcription factors and target genes in cancer. In this study, we examined the role of IL-1alpha in the activation of NFkappaB and AP-1, the expression of proangiogenic cytokine IL-8, and in the survival and proliferation of HNSCC cell lines. HNSCCs were found to secrete and respond to functional IL-1alpha, in that culture supernatant from a high IL-1alpha-secreting line, UM-SCC-11B, could induce secretion of cytokine IL-8 by a low IL-1alpha-secreting line, UM-SCC-9; and the induction of IL-8 secretion could be blocked by the anti-IL-1alpha-neutralizing antibody or the IL-1 receptor antagonist (IL-1RA). Furthermore, IL-1alpha could induce the expression of IL-8 through an autocrine mechanism, in that transfection of UM-SCC-9 cells with a plasmid encoding IL-1alpha resulted in the increased coexpression of IL-1alpha and IL-8; whereas transfection with a plasmid encoding IL-1RA lacking the secretory leader sequence led to the decreased coexpression of IL-1alpha and IL-8. IL-1alpha was found to induce coexpression of IL-8 through the activation of NFkappaB and AP-1, in that mutation of the NFkappaB site within the IL-8 promoter abolished autocrine- and recombinant IL-1alpha-induced IL-8 reporter gene activity, whereas mutation in AP-1 partially decreased IL-8 reporter gene activity in UM-SCC-9 cells. Intracellular expression of IL-1RA decreased NFkappaB reporter gene activity, indicating that endogenously expressed IL-1alpha contributes to constitutive NFkappaB activation in this HNSCC line. Expression of IL-1alpha affected survival of UM-SCC-9, inasmuch as transfection of cells with plasmid encoding IL-1alpha or IL-1RA led to the increased or decreased survival of cells cotransfected with a beta-galactosidase reporter gene, respectively. IL-1alpha was also found to promote the increased growth of UM-SCC-9 cells in vitro. We demonstrate that exogenous and endogenous IL-1alpha contributes to the transcriptional activation of NFkappaB and AP-1, to the expression of IL-8, and to cell survival and the growth of HNSCC in vitro.

Comparison of shockwave lithotripsy outcomes in patients receiving sufentanil or lidocaine spinal anesthesia

PURPOSE

To determine whether the use of intrathecal sufentanil, which allows the patient to move during shockwave lithostripsy (SWL), affects treatment outcomes and operative and recovery times compared with standard lidocaine spinal anesthesia.

PATIENTS AND METHODS

We retrospectively studied a series of 62 SWL procedures performed on an unmodified Dornier HM3 lithotripter. The mean calculus size was 10.7 mm. There were 46 renal calculi, 13 ureteral calculi, and 4 patients with calculi in both locations. Of the 63 procedures, 25 were performed using intrathecal sufentanil alone, and 37 were performed with intrathecal lidocaine with or without additional agents. We compared treatment outcomes, as well as treatment time, fluoroscopy time, postanesthesia care unit (PACU) time, time to voiding, and time to ambulation.

RESULTS

Sufentanil use was associated with a significantly higher rate of successful treatment, defined as residual fragments absent or <4 mm on follow-up imaging, compared with lodocaine: 68% v. 40% (p = 0.0394). There was no significant difference between the groups in treatment time or fluoroscopy time. Use of sufentanil was associated with significantly shorter PACU time, time to ambulation, and time to voiding postoperatively. These differences persisted when men and women were analyzed separately, although the differences were less significant in women.

CONCLUSIONS

The use of intrathecal sufentanil for anesthesia during SWL does not adversely affect treatment outcome; it is, in fact, associated with better outcomes. The advantages of this agent in shortening recovery times and in easing patient transfer into the HM3 gantry argue for increasing its use.

Indications, technique, and results of laparoscopic pelvic lymphadenectomy

Despite considerable clinical research, there is still controversy about the optimal management of the pelvic lymph nodes in men with prostate cancer. This article reviews the creation and application of selection criteria for laparoscopic pelvic lymphadenectomy and describes the various techniques.

Laparascopic partial nephrectomy

The role of laparoscopy in urologic surgery has greatly increased over the past decade as has the popularity of elective nephron-sparing surgery. The emergence of these trends in conjunction with improvements in equipment and expertise has led to the increasing application of laparoscopic partial nephrectomy. Initially, this modality was applied in patients with benign diseases, such as chronic pyelonephritis and calculus disease with associated atrophy. Concerns of tumor spillage and local-regional control precluded the application of the laparoscopic modality to small, indeterminate renal masses. However, increasing experience with the technique and advances in intraoperative imaging have prompted its use in removing small renal masses. Herein, we describe the indications for laparoscopic partial nephrectomy, the two approaches (transperitoneal and extraperitoneal) to gain access to the kidney, current options to assist in controlling intraoperative hemorrhage, a comprehensive assessment of the results for benign and malignant resections, and an examination of the similarities and contrasts between open and laparoscopic techniques.

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.

Functional effects of unilateral laser papillectomy in the pig

OBJECTIVES

To evaluate the use of endoscopic laser papillectomy in a multi-papillary animal model to unilaterally impair concentrating ability and increase the urinary flow rate.

METHODS

Domestic pigs underwent unilateral retrograde flexible nephroscopy. With a holmium:yttrium-aluminum-garnet laser, varying numbers of papillae were ablated. Four weeks after the procedure, renal function studies were performed during hydropenia and after hydration, the animals were killed, and the kidneys were examined histologically.

RESULTS

The urine flow rate per 100 mL creatinine clearance was significantly increased in the papillectomized kidney compared with the control kidney during hydropenia (1.50 versus 0.94, P <0.01). The papillectomized kidneys were unable to concentrate the urine as well as the control kidneys during both hydropenia (urine osmolarity 430 versus 534 mOsm/L, P <0.01) and after hydration (329 versus 362 mOsm/L, P = 0.02). The free water reabsorption per 100 mL creatinine clearance was impaired in the papillectomized kidneys compared with the control kidneys (0.48 versus 1.00, P = 0.02) after hydration. A significant correlation existed between the percentage of papillae ablated and the difference in osmolarity between the operated and control kidneys (r(2) = 0.50, P = 0.015). Histologic examination demonstrated transitional re-epithelialization with moderate collecting duct dilation and medullary fibrosis underlying the ablated papillae early in the series; however, the histologic features normalized and the creatinine clearance was less impaired with a more proficient technique later in the series.

CONCLUSIONS

Endoscopic laser papillectomy results in increased urine flow and impaired urinary concentrating ability. This surgical technique should be investigated further for its role in the prevention of nephrolithiasis.

Comparison of 2-octyl cyanoacrylate adhesive, fibrin glue, and suturing for wound closure in the porcine urinary tract

OBJECTIVES

To evaluate 2-octyl cyanoacrylate glue (OCG) for wound closure in the urinary tract and compare the ability of OCG, fibrin glue (FG), and suture to withstand physiologic and supraphysiologic stress, because the use of tissue adhesives such as OCG or FG might simplify laparoscopic surgery.

METHODS

Female domestic pigs (n = 22) underwent a 7.5-cm cystotomy. Of these, 8 had closure with OCG and 8 with FG (6 open and 2 laparoscopic in each group). The controls were closed with suture (n = 4) or not at all (n = 2). Postoperative catheter drainage was not used. At 2 days or 4 weeks postoperatively, the bladders were filled with saline to 200 mm Hg pressure and the cystotomy scars inspected for leakage. The excised scars were also examined histologically.

RESULTS

The 2 OCG and 2 FG pigs tested on postoperative day 2 leaked at less than 200 mm Hg. None of the 6 OCG pigs tested at 4 weeks leaked at less than 200 mm Hg, including the 2 closed laparoscopically. Of the 6 FG pigs intended for study at 4 weeks, 3 (including the 2 closed laparoscopically) died from a massive urine leak, 1 tested at 4 weeks leaked, and 2 did not leak. Thus, 4 of 6 FG pigs leaked by 4 weeks compared with none in the OCG group (P = 0.06). The histologic examination was similar in the two groups.

CONCLUSIONS

Preliminary results suggest that OCG provides enough strength to hold together a large bladder wound. In the same model, FG did not consistently provide adequate closure.

Laparoscopic access with a visualizing trocar

Although useful in most situations, there are several inherent disadvantages of the standard laparoscopic access techniques of Veress needle insertion and Hasson-type cannula placement. Veress needle placement may be hazardous in patients at high risk for intraabdominal adhesions and difficult in patients who are obese. The usual alternative, the Hasson-type cannula, often does not provide a good gas seal. As another option, the use of a visualizing trocar (OPTIVIEW) has proven to be effective in the initial experience at the University of Michigan. The inner trocar of the visualizing trocar is hollow except for a clear plastic conical tip with two external ridges. The trocar-cannula assembly is passed through tissue layers to enter the operative space under direct vision from a 10-mm zero-degree laparoscope placed into the trocar. Results suggest that this technique is an excellent alternative to Veress needle placement when laparoscopic access is likely to be hazardous or difficult.

Hand-assisted laparoscopic nephrectomy: technical considerations

PURPOSE

Laparoscopic nephrectomy can be technically difficult and associated with lengthy operative times because of the limitations imposed by working with long instruments rotating about a fixed site on the abdominal wall, and without direct manual contact with the tissue. Hand-assisted laparoscopy is an option that addresses these problems. Herein we report our initial technique for hand-assisted laparoscopic nephrectomy.

TECHNIQUE

After obtaining pneumoperitoneum and placing a 12-mm cannula lateral to the rectus muscle, a 7- to 8-cm incision is made in the upper midline. A commercially available wound protector and occlusive sleeve are inserted. Once an arm strap has been secured, the surgeon can operate with one hand in the abdomen while maintaining pneumoperitoneum. Using instruments placed through one or two additional laparoscopic ports, the nephrectomy is completed and the specimen is removed through the upper midline incision. Our continued experience with 10 hand-assisted laparoscopic nephrectomies to date has been favorable.

CONCLUSION

Hand-assisted laparoscopic nephrectomy may facilitate the laparoscopic management of demanding pathologies, such as severely inflamed kidneys and larger tumors. It is particularly advantageous when intact specimens are required. Although more experience is required to define the role of hand-assisted urologic laparoscopy, we are encouraged by our initial technique and results.

Fragment of a catheter as a foreign body in the kidney

Foreign bodies in the kidney are unusual. A review of the literature disclosed few reports of renal foreign body from nontraumatic causes. In this article, we report a case of gross hematuria due to iatrogenic foreign body in the kidney from ureteral endoscopy. The catheter fragment eluded diagnosis for 18 months until it was discovered and retrieved by means of a flexible ureteroscope. To our knowledge, this is the first report of this complication and presentation following endoscopic manipulation of the upper ureteral tract.

Asymptomatic microscopic hematuria in adults: summary of the AUA best practice policy recommendations

The American Urological Association (AUA) convened the Best Practice Policy Panel on Asymptomatic Microscopic Hematuria to formulate policy statements and recommendations for the evaluation of asymptomatic microhematuria in adults. The recommended definition of microscopic hematuria is three or more red blood cells per high-power microscopic field in urinary sediment from two of three properly collected urinalysis specimens. This definition accounts for some degree of hematuria in normal patients, as well as the intermittent nature of hematuria in patients with urologic malignancies. Asymptomatic microscopic hematuria has causes ranging from minor findings that do not require treatment to highly significant, life-threatening lesions. Therefore, the AUA recommends that an appropriate renal or urologic evaluation be performed in all patients with asymptomatic microscopic hematuria who are at risk for urologic disease or primary renal disease. At this time, there is no consensus on when to test for microscopic hematuria in the primary care setting, and screening is not addressed in this report. However, the AUA report suggests that the patient's history and physical examination should help the physician decide whether testing is appropriate.

Renal transplantation at the University of Michigan 1964 to 1999

The Michigan Kidney Transplant Program has existed for 35 years. Outcomes have improved dramatically as the one-year survival of cadaver kidney grafts increased from 25% to 85-90%. Patient deaths in the first year are now uncommon. Indications for renal transplantation have been extended to infants, the elderly, diabetics and to patients with other significant health problems who would not have been candidates in the past. Chronic administration of large doses of corticosteroids is no longer necessary and the associated morbidity is largely avoided. Improvements in immunosuppression, especially the introduction of cyclosporine, account for much of this progress. With success has come increasing demand. Unfortunately, the gap between the number of available donor kidneys and the number of patients listed for a cadaver transplant continues to increase rather than diminish. Greater acceptance of volunteer donation, as has occurred in our own program, will help to reduce this shortage. If the past forecasts the future, we can anticipate extraordinary advances during the next 35 years.

Use of bowel in laparoscopic urology

Minimally invasive urology is a rapidly expanding field. What once was thought technically impossible is now becoming a reality, especially with the advent of intracorporeal stapling and automated suturing devices. Laparoscopic assistance and pure laparoscopy improve convalescence and cosmesis in comparison with open surgical procedures. Minimally invasive continent urinary stomas, ACE procedures, bladder augmentation, urinary diversion, and urinary undiversion have all been described in clinical practice. Continent urinary diversions and ileal bladder augmentations are being developed. Eventually, even the most challenging urologic procedures will be performed in a minimally invasive manner.

Evaluation and management of traumatic posterior urethral disruption with flexible cystourethroscopy

BACKGROUND

We sought to consolidate evaluation and management of traumatic urethral disruption using cystourethroscopic evaluation without retrograde urethrogram or suprapubic cystostomy placement.

METHODS

We review our experience with initial flexible cystourethroscopic evaluation of suspected urethral injury from blunt trauma with placement of a Council urethral catheter to provide primary endoscopic realignment of the urethra.

RESULTS

Access into the bladder was achieved in 8 of 10 patients. After a mean follow-up of 18 months (range, 9-27 months) in the six living patients, only three have required treatment for urethral stricture--direct vision internal urethrotomy in two, and open perineal urethroplasty in one. Urinary continence has been achieved in five of six patients.

CONCLUSION

Primary flexible cystourethroscopy with placement of a urethral catheter streamlines evaluation of traumatic posterior urethral injury. In the presence of partial disruption it provided stricture-free outcomes in three of three surviving patients.

Prospective comparison between hand-assisted laparoscopic and open surgical nephroureterectomy for urothelial cell carcinoma

OBJECTIVES

To prospectively compare open surgical and the new hand-assisted approach to laparoscopic nephroureterectomy for urothelial cell carcinoma. Previous retrospective studies have suggested that standard laparoscopic nephroureterectomy provides a briefer convalescence than open surgical nephroureterectomy.

METHODS

Between March 1997 and September 1999, 16 hand-assisted laparoscopic and 11 open surgical nephroureterectomies were performed, without randomization. Validated questionnaires were prospectively administered preoperatively and 2 and 6 weeks postoperatively.

RESULTS

The operative time was longer with the laparoscopic approach (320 versus 199 minutes, P <0.001), but the hospital stay was shorter (3.9 versus 5.2 days, P = 0.03). Patient recovery favored the laparoscopic group with regard to time to drive (17.1 versus 37.7 days), time to normal, nonstrenuous activity (18.2 versus 38.1 days), and the mental component score of the SF-12 survey at 6 weeks (57.1 versus 43.0) (P <0.05 for all). Minor complications occurred in 19% of the laparoscopic and 45% of the open surgical procedures; major complications occurred in 19% of laparoscopic and 27% of open surgical procedures (P >0.1 for both). Cancer control was similar between both groups. The mean operating room cost was 56% more for the laparoscopic group (P <0.001), but the overall hospital cost was only 8% greater (P >0.3).

CONCLUSIONS

Hand-assisted laparoscopic nephroureterectomy is a safe and effective alternative to an open surgical approach. Indexes of patient recovery suggest that patient convalescence is less than after an open surgical nephroureterectomy. Increased operative costs may be offset by a shorter hospital stay and fewer complications, resulting in similar overall hospital costs.

Technical advances in laparoscopy: hand assistance, retractors, and the pneumodissector

Technology is crucial to the laparoscopic surgeon. Reducing the technical difficulty of laparoscopic procedures is beneficial on many fronts: training is facilitated, operative time is reduced, and the practice of minimally invasive surgery can be further disseminated. Many advances in urologic laparoscopic surgery are attributable to the development of new operative instruments that reduce the technical difficulty. In this article, we highlight three technical advances in laparoscopy. Hand assistance can simplify many laparoscopic procedures. Because the surgeon retains tactile sensation, operative times are reduced compared with standard laparoscopic surgery, with minimal, if any, increase in patient morbidity. Other advances in instrumentation include various laparoscopic retractors and the Pneumodissector, a unique dissecting device. The breadth of retractors extends from reusable metal "fans" to disposable inflated "paddles," with many in between. The metal retractors may be more traumatic to delicate tissues than the inflatable ones but also are more versatile. The Pneumodissector facilitates tissue dissection by releasing short burst of carbon dioxide. It is a safe and effective instrument for blunt tissue dissection. These technical advances have contributed to the progression of laparoscopic urologic procedures. Technology will continue to have a significant impact on the advancement of laparoscopic urology and its potential widespread dissemination.

Caliceal diverticulum and hydrocalyx. Laparoscopic management

Laparoscopic treatment of caliceal diverticula or hydrocalyces is an excellent choice for anterior cavities without significant overlying renal parenchyma that are large or that have an endoscopically inaccessible neck and either a narrow neck or large stone burden.

Laparoscopic tissue approximation

Although many extirpative urologic laparoscopic procedures are starting to be generally accepted, there is limited application of recontructive urologic laparoscopic procedures. Difficulties with laparoscopic tissue approximation account for a large portion of the slow development of recontructive laparoscopic urology. In this paper, the current state of laparoscopic tissue approximation is reviewed, research efforts in this area are summarized, and future directions are considered. The discussion addresses available techniques and devices, as well as those in development for future application.

Survey of neuromuscular injuries to the patient and surgeon during urologic laparoscopic surgery

OBJECTIVES

Laparoscopy may be complicated by neuromuscular injuries, both to the patient and to the surgeon. We used a survey to estimate the incidence of these injuries during urologic laparoscopic surgery, to assess risk factors for these injuries, and to determine preventive measures.

METHODS

A survey of neuromuscular injuries associated with laparoscopy submitted to 18 institutions in the United States was completed by 18 attending urologists from 15 institutions.

RESULTS

From among a total of 1651 procedures, there were 46 neuromuscular injuries in 45 patients (2.7%), including abdominal wall neuralgia (14), extremity sensory deficit (12), extremity motor deficit (8), clinical rhabdomyolysis (6), shoulder contusion (4), and back spasm (2). Neuromuscular injuries were twice as common with upper retroperitoneal as with pelvic laparoscopy (3. 1% versus 1.5%). Among patients with neuromuscular injuries, those with rhabdomyolysis were heavier (means 91 versus 80 kg) and underwent longer procedures (means 379 versus 300 minutes), and those with motor deficits were older (means 51 versus 42 years of age). Of the surgeons, 28% and 17% reported frequent neck and shoulder pain, respectively.

CONCLUSIONS

Although not common, neuromuscular injuries during laparoscopy do contribute to morbidity. Abdominal wall neuralgias, injuries to peripheral nerves, and joint or back injuries likely occur no more frequently than during open surgery, but risk of rhabdomyolysis may be increased. Positioning in a partial rather than full flank position may reduce the incidence of some injuries. Measures to reduce neuromuscular strain on the surgeon during laparoscopy should be considered.

Nephron sparing surgery for suspected malignancy: open surgery compared to laparoscopy with selective use of hand assistance

PURPOSE

Laparoscopic nephron sparing surgery has been reported rarely, likely due to technical difficulty when using only laparoscopic instrumentation. Hand assisted techniques may facilitate the procedure in select cases while maintaining the benefits of minimally invasive surgery. We prospectively compared the laparoscopic with selective hand assistance and open surgical approaches to nephron sparing surgery for suspected malignancy.

MATERIALS AND METHODS

We compared our initial 10 laparoscopic nephron sparing procedures for suspected malignancy, including 8 with hand assistance, in 9 patients (11 tumors) with 11 consecutive open surgical procedures for similar indications. Standard laparoscopic technique was used in cases of an exophytic mass with shallow penetration into the parenchyma. Otherwise hand assistance was used. Recovery data were obtained prospectively using self-administered questionnaires.

RESULTS

Although mean operative time was 24% greater in the laparoscopic group, recovery was more favorable than in the open surgical group, as evidenced by 62% less parenteral narcotic use, 43% shorter hospital stay, 64% more rapid return to normal nonstrenuous activity, and improved pain and physical health scores 2 and 6 weeks postoperatively. In each group mean lesion diameter was 2.4 cm., 8 of 11 neoplasms were malignant and no margins were positive for malignancy. There were no conversions to open surgery and no major complications in the laparoscopic group.

CONCLUSIONS

Laparoscopic nephron sparing surgery appears to have an advantage over open surgery in terms of patient recovery. Facilitation by hand assistance may make laparoscopic nephron sparing surgery a more widely available, minimally invasive alternative to open surgery for small, favorably located renal tumors.

Prospective, case matched comparison of hand assisted laparoscopic and open surgical live donor nephrectomy

PURPOSE

The technical difficulty of standard laparoscopic live donor nephrectomy has limited its application. Hand assistance, which takes advantage of the incision necessary for organ removal, facilitates laparoscopy without significant impact on patient recovery. We prospectively compared open surgical and hand assisted laparoscopic donor nephrectomy.

MATERIALS AND METHODS

Our first 10 laparoscopic live donor nephrectomies were matched with 40 open donor nephrectomies by gender, age and body mass index. Data were obtained by pain scales, SF-12 survey instruments, questionnaires and chart abstraction.

RESULTS

Operative time was longer for the laparoscopic approach (mean 95 versus 215 minutes). However, laparoscopic group patients had a shorter hospital stay compared to those undergoing open surgery (mean 2.9 versus 1.8 days), returned sooner to nonstrenuous activity (mean 19.0 versus 9.9 days) and reported less pain 6 weeks postoperatively (mean 2.3 versus 0.6) (p </=0.03 for all). There were no differences between groups in terms of donor complications, allograft function and ureteral complications. Mean hospital cost was 23% greater in the laparoscopic group (p = 0.005) but global cost, which accounted for estimated loss of income from work during the recovery period, was only 15% greater (p = 0.10). Mean operative time was significantly improved for our second compared to our first 5 laparoscopic group patients (177 versus 254 minutes).

CONCLUSIONS

Laparoscopic live donor nephrectomy appears to be a safe and effective alternative to open donor nephrectomy. Indexes of patient recovery suggest patient morbidity similar to that reported following standard laparoscopic donor nephrectomy and significantly less than after open nephrectomy. Improvement in operative time in the first 10 cases suggests that hand assistance "shortens" the learning curve, which might encourage more surgeons to offer laparoscopic live donor nephrectomy.

Appropriateness of routine postoperative chest radiography after tracheotomy

OBJECTIVE

To determine the appropriateness of postoperative chest radiography after adult tracheotomy.

DESIGN

Retrospective case series.

SETTING

Tertiary care academic medical center.

PATIENTS

The records of 379 consecutive adult patients who underwent tracheotomy by the Otolaryngology-Head and Neck Surgery Service from January 1992 to December 1996 were available for review and met inclusion criteria. All patients underwent postoperative chest radiography.

MAIN OUTCOME MEASURES

Frequency of postoperative tracheotomy-associated complications, most significantly pneumothorax.

RESULTS

The patients had no pneumothorax on postoperative chest films. Minor complications, which were found in 7.1% of the patients, included small bleeds, wound infection, and subcutaneous emphysema. Tracheostomy-associated death occurred in 2 patients (0.5%).

CONCLUSIONS

Routine postoperative chest radiography is unnecessary after adult tracheotomy. Chest radiography may be indicated by clinically suspicious signs or symptoms.

Clinical effectiveness of new stent design: randomized single-blind comparison of tail and double-pigtail stents

BACKGROUND AND PURPOSE

Stent morbidity appears to be secondary to lower urinary tract irritation. In an effort to decrease stent morbidity, a "one size fits all" Tail stent (Microvasive [Boston Scientific] Natick, MA) was developed with a 7F proximal pigtail and 7F shaft which tapers to a lumenless straight 3F tail.

PATIENTS AND METHODS

We randomized 60 patients in a single-blind fashion to a 7F tail stent or 7F double-pigtail Percuflex stent. Patients were evaluated at the time of stent removal and 2 weeks later with a standardized questionnaire assessing: irritative lower tract symptoms individually and on a total scale of 0 (no symptoms) to 30 (worst symptoms), obstructive lower tract symptoms (on a total scale of 0-20), and upper tract irritative symptoms (on a total scale of 0-10).

RESULTS

Patient age, weight, and height were similar in the two groups. Complications, including fever, urinary tract infections, emergency room visits, and the need for antispasmodics and pain medication, also demonstrated no significant difference. At the time of stent removal, patients who received a tail stent had significantly less urinary frequency and a statistically significant (21%) decrease in overall irritative voiding symptoms (12.2 v 15.4; p = 0.048). Two weeks after stent removal, the total irritative voiding symptoms was markedly decreased in both groups (7.1 in the Tail v 5.3 in the double-pigtail group; p = 0.15). Obstructive bladder and flank symptoms were not significantly different in the two stent groups, either at the time of stent removal or at 2 weeks after removal.

CONCLUSION

In this randomized, single-blind study, the 7F Tail stent produced significantly less irritative symptoms than did the standard 7F double-pigtail stent. Obstructive symptoms tended to be less with the new stent, while flank symptoms were similar.

Comparison of transperitoneal laparoscopic access techniques: Optiview visualizing trocar and Veress needle

PURPOSE

We retrospectively compared the safety, efficacy, and relative indications of the Optiview visualizing trocar and the Veress needle for obtaining transperitoneal laparoscopic access.

PATIENTS AND METHODS

Of 100 consecutive transperitoneal laparoscopic procedures performed by a single surgeon, the Veress needle was used initially in 96 patients. The Optiview was used on 26 occasions: in 4 patients as the initial access attempt, and in 22 patients after the Veress needle had failed. Patient characteristics (age, body mass index [BMI], American Society of Anesthesiologists [ASA] score, and history of abdominal surgery), success rates, and complications were compared.

RESULTS

Access was obtained successfully with the Optiview in 25 of 26 cases (96%), whereas the Veress needle was successful in 72 of 96 (75%; P = 0.02). The Hasson cannula was used successfully after two of the Veress needle failures and the single Optiview failure. Age, BMI, ASA score, and history of abdominal surgery were not associated with access failure. There were no Optiview-related complications. Use of the Hasson cannula was not associated with any complications, but it was difficult to place, leaked gas, or both in two of the three patients. There were four Veress-related access complications (all minor): one colon insufflation, two retroperitoneal hematomas, and one liver laceration.

CONCLUSIONS

As an alternative to the Hasson cannula, the Optiview visualizing trocar is a safe and highly effective method of obtaining transperitoneal laparoscopic access, particularly in those patients in whom difficulty is encountered with the Veress needle. However, the needle is less expensive and, in our experience, has not been associated with significant complications. Because we were unable to determine objective patient characteristics that increase the risk for Veress needle failure, we continue to use it for the first attempts at transperitoneal access in most patients.

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.

Constitutive activation of transcription factors NF-(kappa)B, AP-1, and NF-IL6 in human head and neck squamous cell carcinoma cell lines that express pro-inflammatory and pro-angiogenic cytokines

We previously reported that human head and neck squamous cell carcinomas (HNSCCs) express the pro-inflammatory and pro-angiogenic cytokines interleukin (IL)-1alpha, IL-6, IL-8, and granulocyte-macrophage colony-stimulating factor in vitro and in vivo. The promoter region of the genes encoding these cytokines include binding sites for the transcription factors nuclear factor (NF) kappaB/Rel A, activator protein-1 (AP-1), and CCAAT enhancer-binding protein beta (C/EBPbeta, or NF-IL6), which have been reported to contribute to activation of these cytokine genes. In the study presented here, we examined the activation, composition, and function of these transcription factors in HNSCC cell lines that express pro-inflammatory cytokines, by using electrophoretic mobility shift and reporter-gene assays. Constitutive activation of NF-kappaB, AP-1, and NF-IL6 DNA-binding proteins was detected. Supershift analysis with antibodies specific for NF-kappaB, AP-1, and NF-IL6 binding proteins showed that the NF-kappaB-binding protein included p65/Rel A and p50; AP-1 activity included c-jun, junB, junD, and Fra-1; and NF-IL6 included C/EBPbeta. Mutational analysis of the NF-kappaB, AP-1, and NF-IL6 sites in the IL-8 promoter region showed that NF-kappaB and AP-1 sites contributed to constitutive IL-8 reporter activity in HNSCC. HNSCC lines that exhibited increased IL-8 secretion relative to simian virus 40-immortalized and primary keratinocyte cell lines also demonstrated a concordant increase in NF-kappaB reporter activity relative to nonmalignant keratinocytes. We concluded that the early transcription factors NF-kappaB, AP-1, and NF-IL6 are constitutively activated in human HNSCC cell lines and that NF-kappaB and AP-1 promote expression of the pro-inflammatory and pro-angiogenic cytokine IL-8 in HNSCC. The demonstration of the activation of these transcription factors will be helpful in defining the identity and role of these and other early gene products that contribute to pathogenesis of the malignant phenotype in HNSCC and in defining potential targets for pharmacologic and molecular therapy of HNSCC. Mol. Carcinog. 26:119-129, 1999. Published 1999 Wiley-Liss, Inc.

Review of antibiotic prophylaxis recommendations for office-based urologic procedures

Prophylactic antibiotic recommendations for urologic procedures are not well established. Any assessment of the need for antibiotics entails thorough cost-benefit analysis. The subject of this article is an evaluation of the role of antimicrobial prophylaxis for outpatient office-based diagnostic procedures, including diagnostic flexible cystoscopy, transrectal ultrasound biopsy, and urodynamics. Relevant studies were identified using MEDLINE database searches and review of selected bibliographies. Studies of infections after transrectal ultrasound and biopsy suggest that periprocedure antibiotics are indicated, but that the exact course and timing have not been defined. Most evidence suggests that outpatient cystoscopy is associated with minimal infectious risk and that the routine administration of oral antibiotics is not indicated. Support in the literature for the use of prophylactic antibiotics at the time of urodynamic evaluation is equivocal. The current prophylactic regimens at the University of Michigan are presented as recommendations, but optimization of antimicrobial prophylaxis will require multicenter studies with large numbers of patients.

Expression of a dominant-negative mutant inhibitor-kappaBalpha of nuclear factor-kappaB in human head and neck squamous cell carcinoma inhibits survival, proinflammatory cytokine expression, and tumor growth in vivo

We demonstrated recently that constitutive expression of proinflammatory cytokines interleukin (IL)-1alpha, IL-6, IL-8, and granulocyte-macrophage colony-stimulating factor in head and neck squamous cell carcinoma is correlated with activation of transcription factor nuclear factor (NF)-kappaB/Rel A (p50/p65), which binds the promoter region within each of the genes encoding this repertoire of cytokines. NF-kappaB can be activated after signal-dependent phosphorylation and degradation of inhibitor-kappaBalpha and has been reported to promote cell survival and growth. In the present study, we expressed a phosphorylation site mutant of inhibitor-kappaBalpha (IkappaBalphaM) in head and neck squamous cell carcinoma lines UM-SCC-9, -11B, and -38 to determine the effect of inhibition of NF-kappaB on cytokine expression, cell survival in vitro, and growth in vivo. After transfection with IKBalphaM, only a few UM-SCC-9 clones were obtained that stably expressed the mutant IkappaB, suggesting that expression of a mutant IkappaBalpha may affect survival of the transfected UM-SCC cell lines. After cotransfection of IkappaBalphaM with a Lac-Z reporter, we found that the number of surviving beta-galactosidase-positive cells in the three cell lines was reduced by 70-90% when compared with controls transfected with vector lacking the insert. In UM-SCC-9 cells that stably expressed IkappaBalphaM, inhibition of constitutive and tumor necrosis factor-a induced NF-kappaB activation, and production of all four cytokines was observed. Although UM-SCC-9 IkappaBalphaM-transfected cells proliferated at the same rate as vector-transfected cells in vitro, a significant reduction in growth of tumor xenografts was observed in SCID mice in vivo. The decreased growth of UM-SCC-9 IkappaBalphaM-transfected tumor cells accompanied decreased immunohistochemical detection of the activated form of NF-kappaB in situ. These results provide evidence that NF-KB and IkappaBalpha play an important role in survival, constitutive and inducible expression of proinflammatory cytokines, and growth of squamous cell carcinoma. NF-kappaB could serve as a potential target for therapeutic intervention against cytokine and other immediate-early gene responses that contribute to the survival, growth, and pathogenesis of these cancers.

Success of the modified Epley maneuver in treating benign paroxysmal positional vertigo

OBJECTIVE

Benign paroxysmal positional vertigo (BPPV) is a common condition seen by otolaryngologists. The purpose of this study is to determine the ability of the modified Epley maneuver to treat BPPV.

STUDY DESIGN

Retrospective review.

METHODS

A retrospective chart review of 107 patients diagnosed with BPPV at our institution between March of 1993 and June of 1995. Each patient was diagnosed with isolated BPPV by history and Hallpike-Dix maneuver. There were no other vestibular symptoms or electronystagmogram abnormalities. Patients diagnosed with BPPV received modified Epley maneuvers, were instructed to remain upright for 48 hours, and wore a soft collar for a week. Patients were followed up with repeat Hallpike-Dix maneuvers at 1 to 2 weeks. If symptoms persisted, the maneuver was repeated for up to a maximum of three times, at which point patients were considered to have failed treatment.

RESULTS

The average age of patients was 57.8 years old. Thirty percent were male and the right ear was affected in 54%. The posterior semicircular canal was affected in 105 ears. The average patient received 1.23 Epley maneuvers, with a success rate of 93.4%. No successfully treated patients received mastoid vibration. Seven out of 107 patients failed after three Epley maneuvers. Two failure patients had a history of temporal bone fracture. Two failure patients were treated with posterior semicircular canal block surgery.

CONCLUSION

The modified Epley maneuver is an excellent treatment for BPPV.

Determinants of waiting time for heart transplants in the United States

BACKGROUND

Reports have been published on factors affecting the variations in waiting times for kidney and liver transplant candidates who have been registered on the United Network for Organ Sharing's waiting list. This study reports on determinants of waiting time differences that occur in the eleven UNOS regions for heart transplant candidates.

METHODS

Retrospective analysis of 11,345 primary heart waiting-list registrations and 15,868 cadaveric donors, from whom 7,043 hearts were recovered and transplanted for the years 1994-96. Because estimated populations in the eleven UNOS regions vary from 10.8 to 43.2 million, analyses utilized Registrations/million population and Transplants/million population to obtain an R/T ratio. The relationship of the R/T ratio to the median waiting time was then examined for different demographic variables.

RESULTS

The numbers of new heart candidate registrations, heart transplants performed, and waiting list deaths have undergone little change from 1991 through 1996. National median waiting times varied by basic demographic variables such as ABO blood type, race, age group, and UNOS medical urgency status. In the eleven UNOS regions, registrations per million ranged from 11.5 to 33.0 and transplants per million from 5.3 to 10.7. Registration/Transplant ratios correlated with median waiting times for urgency Status 1 and 2 as well as for blood group O recipients. Correlation with blood type AB recipients was less consistent, in part, due to the small number of AB recipients.

CONCLUSIONS

There are wide variations in the number of heart transplant candidate registrations and in the number of heart transplants performed in the eleven UNOS regions. The registration to transplantation ratio correlated with median waiting times in these regions. Factors possibly contributing to the observed variations were examined.

Antifibrinolytic additives to fibrin glue for laparoscopic wound closure in urinary tract

BACKGROUND AND OBJECTIVES

Fibrinolytic activity of urine may rapidly degrade fibrin glue used in the urinary tract, thereby limiting tissue adhesion. The goals of this study were to verify the ability of antifibrinolytic agents to delay the degradation of fibrin glue in the urinary tract and to assess the results of this delay on subsequent wound healing.

MATERIALS AND METHODS

In 25 domestic pigs, a 3.5-cm incision in the urinary bladder was left open (N = 6) or closed laparoscopically with fibrin glue alone (N = 6), fibrin glue containing aprotinin 5000 KIU/mL (N = 6), or fibrin glue containing aprotinin 2500 KIU/mL with (N = 4) or without (N = 3) aminocaproic acid 12.5 mg/mL. At harvest 7 days later, the bladder was tested for leakage. Histologic features were scored by a pathologist blinded to the closure method.

RESULTS

There were no significant differences among the groups in the amount of leakage at harvest. Significant fibrin glue material in the wound was noted more often in the pigs treated with fibrin glue plus aprotinin (7 of 13) than in the fibrin glue-only group (0 of 6; P = 0.04). The presence of significant fibrin material in the wound correlated well with absence of granulation tissue (P < 0.001), such that granulation tissue bridging the wound edges was found more often in the fibrin glue-only group (6 of 6) than in the groups treated with fibrin glue plus aprotinin (4 of 13; P = 0.01).

CONCLUSIONS

Although aprotinin +/- aminocaproic acid did delay the degradation of fibrin glue used to close a bladder wound, it was associated with inhibition of granulation tissue in the glued wound. These findings suggest that aprotinin alone and aprotinin plus aminocaproic acid are not useful additives to fibrin glue used for wound closure in the urinary tract.

Almost totally tubeless percutaneous nephrolithotomy: further evolution of the technique

BACKGROUND AND OBJECTIVES

There is renewed interest in the concept of foregoing placement of the postoperative nephrostomy tube (PNT) after percutaneous nephrolithotomy (PCNL) with the intent of reducing postoperative discomfort and hospital stay. We have omitted the PNT and placed an internal ureteral stent or externalized ureteral catheter after PCNL in selected patients. We reviewed our experience in order to assess the efficacy and safety of this practice.

PATIENTS AND METHODS

Primary PCNL was performed in 26 renal units in 21 patients (5 bilateral PCNL, 4 of which were simultaneous) by one surgeon at the University of Michigan and the Ann Arbor Veterans Affairs Medical Center. A postoperative nephrostomy tube was placed if the stone burden was >3 cm, more than one access site was used, the renal anatomy was obstructive, significant bleeding or perforation was noted, or a second look was required.

RESULTS

No PNT was placed in 10 renal units in 8 patients (no-PNT group). In six no-PNT kidneys, internal ureteral stents were used, and in four, externalized ureteral stents were placed for 1 to 2 days. The mean stone size in the PNT and no-PNT patients was 3.0 and 1.8 cm, respectively. Of the 16 kidneys in the PNT group, 4 were initially eligible for omission of PNT, but a PNT was placed because of bleeding or other access-related problem. All patients were rendered stone free except for three (one PNT and two no-PNT) patients, who each had a fragment < or =4 mm. Omission of PNT placement resulted in decreased mean length of stay (2.3 days in the no-PNT group v 3.6 days in the PNT group). There were four complications, all managed with delayed stenting (one in a no-PNT patient and the remaining three in the PNT group).

CONCLUSION

Omission of PNT placement in selected patients may reduce morbidity without compromising efficacy and safety, but further study is needed.

Renal malacoplakia

We present a well-documented case of biopsy-proven renal malacoplakia with an excellent response to oral fluoroquinolone therapy.

Pneumoperitoneum does not potentiate the nephrotoxicity of aminoglycosides in rats

OBJECTIVES

Pneumoperitoneum is associated with transient renal dysfunction. To our knowledge, the safety of administering nephrotoxins such as aminoglycosides during pneumoperitoneum has not been studied. Our hypothesis was that pneumoperitoneum potentiates the nephrotoxicity of aminoglycosides.

METHODS

From 29 rats we obtained preprocedure 24-hour urine collections. In the pneumoperitoneum group (n = 7), carbon dioxide was insufflated intra-abdominally at 15 mm Hg pressure for 2 hours. In the gentamicin group (n = 7), 10 mg/kg gentamicin was administered intravenously. In the combined pneumoperitoneum/gentamicin group (n = 8), the same dose of gentamicin was administered 10 minutes before pneumoperitoneum. Sham rats (n = 7) received anesthesia only. Urine was collected for the 24 hours after the procedure, and 1 week later blood for creatinine determination and final 24-hour urine collections were obtained. All urine samples were assayed for creatinine and N-acetyl-beta-glucosaminidase (NAG).

RESULTS

Only the gentamicin and combined pneumoperitoneum/gentamicin groups presented day 1 values for NAG excretion that were significantly greater than same day sham or paired preprocedure values; the rest of the urinary creatinine and NAG day 1 levels and all the day 7 levels were not significantly different from same day sham or paired preprocedure levels. Day 7 serum creatinine and creatinine clearance did not differ significantly among the groups.

CONCLUSIONS

We found that intravenous gentamicin transiently increased urinary excretion of NAG in rats, which resolved within 1 week. Pneumoperitoneum for 2 hours at 15 mm Hg did not increase urinary NAG, either alone or in gentamicin-treated rats. Moreover, our data are sufficient to refute with 95% certainty the possibility that gentamicin plus pneumoperitoneum decreases creatinine clearance more than approximately 60%. These results do not support the hypothesis that pneumoperitoneum potentiates the nephrotoxicity of aminoglycosides.