First Prize (tie): Hemorrhage following percutaneous renal surgery: characterization of angiographic findings

PURPOSE

Percutaneous surgery is an established approach to a spectrum of renal pathology, and hemorrhage is the most concerning complication of this technique. We determined the frequency of postoperative hemorrhage requiring selective angioembolization (sae), the efficacy of this approach, and characterized the angiographic findings.

METHODS

We reviewed our database of 4695 patients who underwent percutaneous renal surgery and identified patients requiring SAE for postoperative hemorrhage. Angiographic findings were recorded and efficacy of SAE documented.

RESULTS

Patients undergoing percutaneous stone extraction (PSE; 3685), percutaneous antegrade endopyelotomy (PAE; 850), and upper-tract transitional cell carcinoma (UTTCC) resection (160) were reviewed. We identified 57 patients requiring SAE (1.2%) who underwent 44 PSEs (77.2%), 7 PAEs (12.3%), and 6 UTTCC resections (10.5%). This represented 1.2%, 0.8%, and 3.2% of all PSE, PAE, and UTTCC resections, respectively. Angiography revealed treatable lesions in 94.7% of patients. Overall, 64 angiographic findings were encountered including 30 pseudoaneurysms (53% of patients, 47% of findings), 14 arteriovenous fistulas (AVFs) (25% of patients, 22% of findings), and 14 instances of contrast extravasation (25% of patients, 22% of findings). Two arterial dissections and one instance each of a hypervascular area, a vascular "cut-off" sign, and a fistula between an artery and the percutaneous tract were identified. One bleeding vessel identified at the base of a UTTCC resection was not amenable to embolization. Ten patients (17.5%) had >or=1 angiographic finding. Three patients (5.3%) had no angiographic findings to account for hemorrhage. No angioembolization-related complications occurred. Complete resolution of bleeding was observed in 54 patients (95%).

CONCLUSIONS

Major hemorrhage requiring intervention after percutaneous renal surgery is uncommon. The most common angiographic finding is arterial pseudoaneurysm, followed by arteriovenous fistula, and contrast extravasation. In 95% of cases angiography reveals a demonstrable and treatable etiology. This strongly supports the first-line use of angiography for intractable bleeding in this setting.

Fellowship in endourology, the job search, and setting up a successful practice: an insider's view

The field of endourology, which encompasses genitourinary endoscopy and percutaneous, laparoscopic, and robotic surgery, has advanced rapidly over the past quarter century, causing endourology to be considered a subspecialty of urology. The Endourological Society, which is recognized by the American Urological Association, offers numerous clinical and research fellowship opportunities throughout the world. The decision to seek postresidency fellowship training in endourology is complex as is the process of seeking subsequent employment. We offer guidance on the decision-making process to obtain fellowship training as well as on early steps into subsequent academic or private practice settings.

Pneumoperitoneum with carbon dioxide inhibits macrophage tumor necrosis factor-alpha secretion: source of transitional-cell carcinoma port-site metastasis, with prophylactic irrigation strategies to decrease laparoscopic oncologic risks

PURPOSE

Peritoneal macrophages play a critical role in maintaining local host resistance to infection and malignancy through the secretion of tumor necrosis factor-alpha (TNF-alpha). We hypothesized that attenuated TNF-alpha secretion, as a result of CO(2) pneumoperitoneum, could alter local immune surveillance, thereby contributing to the development of carcinomatosis and incisional metastasis. We further sought to determine if port-site metastasis could be prevented with prophylactic irrigants.

MATERIALS AND METHODS

C57BL/6 mice (n = 50) and the syngenic murine bladder tumor (MBT-2) cell line were used. Experiment 1: Mice were subjected to either CO(2) pneumoperitoneum at 6 mm Hg (n = 10) or a 3-cm midline incision (n = 10). Peritoneal macrophages (1 x 10(6)/animal) were collected and subjected to lipopolysaccharide challenge. TNF-alpha levels were quantified using the Quantikine Mouse TNF-alpha/TNFSF1A Immunoassay. Experiment 2: Peritoneal and port-site metastasis were evaluated 1 week after 1 x 10(6) MBT-2 cells/animal were spilled in an open group (n = 5) and through 5-mm trocars of a pneumoperitoneal group (n = 5). Experiment 3: 1 x 10(6) MBT-2 cells/animal were spilled intraperitoneally through 5-mm trocars of four groups (n = 20). Port sites in each group were then irrigated with either sterile water, mitomycin C (1.0 mg/mL), betadine (10%), or heparin (1000 U/mL). At 1 week, incisional sites were evaluated for gross and microscopic metastasis. In each experiment, Student t-test was used to quantify statistical differences.

RESULTS

Peritoneal macrophage TNF-alpha secretion was significantly inhibited in mice subjected to CO(2) pneumoperitoneum v control at 10 and 20 minutes (P = 0.015, P = 0.001, respectively). When 1 x 10(6) MBT-2 cells were spilled, a significantly higher average tumor burden developed in animals subjected to CO(2) pneumoperitoneum than in controls at 1 week (9.2 gm v 3.8 g, P = 0.002). All irrigants prevented the development of port-site metastasis, yet sterile water did so without toxic effect.

CONCLUSION

In a syngenic murine model, CO(2) pneumoperitoneum causes inhibition of peritoneal macrophage TNF-alpha secretion. Heavier intraperitoneal and incisional metastasis develops in C57BL/6 mice subjected to CO(2) pneumoperitoneum and a tumor challenge with 1 x 10(6) MBT-2 tumor cells compared with open controls. Inhibition of peritoneal macrophage TNF-alpha secretion may be considered an adverse event contributing to the development of transitional-cell carcinoma (TCC) port-site metastasis, especially if surgical oncologic principles are violated. Irrigating trocar sites and the peritoneal cavity with sterile water at the conclusion of laparoscopic nephroureterectomy and laparoscopic radical cystectomy may offer a safe prophylactic strategy to prevent this unfavorable event. Our murine model presents a novel avenue for the development of adjunct immunomodulatory therapies to perhaps further reduce oncologic risks during laparoscopic management of TCC.

Case Report: Successful Conservative Management of Colorenal Fistula after Percutaneous Cryoablation of Renal-Cell Carcinoma

BACKGROUND

Cryoablation is an increasingly utilized treatment for renal-cell carcinoma. We describe the first reported case of colorenal fistula resulting from percutaneous renal cryoablation.

CASE REPORT

A 63-year-old man with hematuria was found to have an enhancing renal mass that was treated with percutaneous CT-guided cryoablation. Two months later, he presented with lower urinary-tract symptoms, and CT imaging revealed a colorenal fistula at the ablation site. Ureteral stent placement resulted in resolution of the fistula.

CONCLUSIONS

Contrary to previously reported animal and clinical studies, our case report demonstrates that it is possible to incur serious harm to the renal collecting system as a result of percutaneous renal cryoablation. In stable patients, an attempt at conservative management of a fistula should precede extensive reconstructive efforts.

Laparoscopy in paediatric urology: present status

The spectrum of laparoscopic surgery in children has developed dramatically; what was initially used as a diagnostic method to identify an impalpable testis is now commonly used for complex reconstructive procedures such as pyeloplasty. Laparoscopic orchidopexy and nephrectomy are well established and are used at many centres. Laparoscopic partial nephrectomy, adrenalectomy and dismembered pyeloplasty series have reported shorter hospital stays and operative times that are comparable with that of open techniques, and/or decreasing with experience. The initial experiences with laparoscopic ureteric re-implantation and laparoscopically assisted bladder reconstructive surgery are reported, with encouraging results for feasibility, hospital stay, and cosmetic outcome.

Laparoscopic versus open radical nephrectomy for xanthogranulomatous pyelonephritis: Contemporary outcomes analysis

BACKGROUND AND PURPOSE

Early experience with laparoscopic nephrectomy for xanthogranulomatous pyelonephritis (XGP) was associated with high conversion and complication rates. We describe our institution's experience with this procedure compared with a contemporary cohort of patients with XGP treated by open nephrectomy.

PATIENTS AND METHODS

Retrospective review of surgical pathology reports from radical nephrectomies at our institution between 1995 and 2005 yielded a diagnosis of XGP in 12 patients, 6 of whom had undergone laparoscopic surgery. Each patient's medical records were reviewed, with intraoperative and postoperative parameters, including complications, being recorded.

RESULTS

Transperitoneal laparoscopic nephrectomy was successful in five patients (83%). Hand-assist ports were utilized in two patients because of failure to progress. The operative times were 301 +/- 106 minutes and 167 +/- 40 minutes in the laparoscopic and open-surgery groups, respectively (P = 0.03). There was no statistical difference with regard to estimated blood loss, transfusion rate, or parenteral analgesic requirements, but there was a trend toward a shorter stay for the laparoscopic group. Complications were noted in three and two patients in the laparoscopic and open-surgery groups, respectively.

CONCLUSIONS

The outcomes of nephrectomy for XGP were similar regardless of surgical approach. The results in patients with XGP were similar to initial reports in the literature and may be dependent on surgeon experience. We believe that in experienced hands, laparoscopic nephrectomy may be offered to patients with XGP.

Novel dual-lumen ureteral stents provide better ureteral flow than single ureteral stent in ex vivo porcine kidney model of extrinsic ureteral obstruction

OBJECTIVES

In the instance of extrinsic ureteral obstruction, indwelling ureteral stents have a high failure rate. Although technically challenging, simultaneous insertion of two ipsilateral stents can achieve better flow rates with time. A novel dual-lumen stent, composed of two adhered ureteral stents, offers the additional benefit of easier placement than a single guidewire. Using a novel ex vivo porcine model, the flow rates within an extrinsically obstructed renal unit were evaluated using two internal ipsilateral stents and two prototype double-lumen stents.

METHODS

Sixteen renal units were harvested from eight adult Yorkshire female pigs. To quantify flow, the kidneys were infused at a constant pressure, and the corresponding ureteral drainage was measured for a defined interval. The flow was measured with a standard 7F double-pigtail stent, two ipsilateral 7F double-pigtail stents, a 7F novel double-lumen stent designed with both distal lumens open, and a 7F novel double-lumen stent with one distal lumen closed. The intraluminal and extraluminal flow in obstructed and nonobstructed systems was measured.

RESULTS

The two ipsilateral standard stents or prototype double stents achieved better flow down the ureter than did one standard stent (P <0.05). The intraluminal and extraluminal flow in the novel stents was statistically greater than the corresponding flow in the standard double-pigtail stent (P <0.01). The extraluminal and obstructed flow was lowest for the standard double-pigtail stent.

CONCLUSIONS

Novel dual-lumen prototype ureteral stents provided better flow than a single stent in extrinsically obstructed ureters with the proposed added benefit of easier retrograde insertion compared with a single guidewire.

Hand Pain During Hand Assisted Laparoscopic Nephrectomy—An Ischemic Event?

PURPOSE

The etiology of hand discomfort during hand assisted laparoscopic nephrectomy may be ischemic in nature. We determined if pneumoperitoneal pressure sustained to the hand during hand assisted laparoscopic nephrectomy poses an occupational risk, contributing to local hand hypoxia and resultant extremity pain.

MATERIALS AND METHODS

A total of 442 measurements of hand oxygen saturation were made during hand assisted laparoscopic nephrectomy. A Nellcor OxiMax Max-1 oxygen sensor was attached to the left index finger of each surgeon and hand assisted laparoscopic nephrectomy was performed using a LapDisc at 15 mm Hg pneumoperitoneal pressures. Local hand oximetry readings and a numerical pain distress scale (range 0 to 10) were recorded every 2 minutes. To control for motion artifact oximetry readings were taken during hand motion and at rest. The Student t test was used to compare differences in local hand oxygen saturation and hand pain in and between study groups.

RESULTS

A history of hand pain during hand assisted laparoscopic nephrectomy was significantly associated with local hypoxia during operative motion and at rest (p = 0.023 and 0.012, respectively), even with an adequate fascial incision and standard pneumoperitoneal pressures. During hand assisted laparoscopic nephrectomy hand pain was most significantly associated with local hypoxia after 24 minutes (p = 0.0002), when local oxygen saturation was 56% to 88%.

CONCLUSIONS

A cohort of urologists is predisposed to ischemic hand pain during hand assisted laparoscopic nephrectomy. The etiology of this pain may be hypoxic in nature, attributable to pneumoperitoneal pressure decreasing perfusion and causing venous congestion or regional local ischemia. Circumferential antebrachial constriction from the LapDisc does not seem to be a significant contributing factor in the presence of an adequate fascial incision. Hand pain secondary to ischemia is most significant after 24 minutes at 15 mm Hg. Future studies in more subjects are called for to validate these findings to elucidate which surgeons are predisposed to this potential occupational hazard and what perioperative measures can be taken to avoid hand pain during hand assisted laparoscopic nephrectomy.