Subcutaneous Nephrovesical and Nephrocutaneous Bypass

Morbidity and long-term results of subcutaneous pyelovesical bypass in chronic ureteral obstruction

BACKGROUND

We present the long-term results and complications of the DETOUR® prosthesis, a permanent subcutaneous pyelovesical bypass for the treatment of ureteral obstruction.

PATIENTS AND METHODS

Between 2006 et 2018, 34 prosthesis were implanted in 28 patients (mean age 65,8 years) with ureteral obstruction of malignant or benign etiologies. The prosthesis, composed to an inner tube of silicone and an outer tube of expanded polytetrafluoroethylene, is placed subcutaneously between the kidney and the bladder. We are performed infrared spectrophotometry and scanning electron microscopy on two removed prostheses to explore the prosthetic encrustation.

RESULTS

The average follow-up was 25,8 months (Maximum: 64 months). Stent revision was required for early bladder fistula in three patients. The major long-term complications were infection (46%), obstruction (3 patients) and bladder fistula (7 patients). The most frequently infection are non-severe, but two patients died from septic shock after fungic colonization of the prosthesis. The infrared spectrophotometry and scanning electron microscopy analysis showed that the obstruction was favored by urinary infection and an alkaline medium. The functional prosthesis rate at 1,2 and 3 years was 94%, 71% and 62%, respectively.

CONCLUSION

The DETOUR® subcutaneous extra-anatomical urinary bypass is an effective and minimally invasive alternative to permanent percutaneous nephrostomy, for both malignant and benign ureteral obstructions in selected patients.

LEVEL OF EVIDENCE

3.

Intestinal perforation involving the Dacron cuff of nephrostomy tubes following subcutaneous ureteral bypass system implantation for ureteral obstructions in two cats

CASE SUMMARY

This case report describes two cats that had subcutaneous ureteral bypass (SUB) systems implanted and subsequently developed duodenal perforations and septic peritonitis associated with the Dacron cuff of the nephrostomy tube. One cat recovered following surgical explantation of the SUB system with intestinal resection and anastomosis of the perforated small intestine, and - at the time of writing - is still alive. The other cat was humanely euthanased intraoperatively at the owner's request owing to its perceived prognosis.

RELEVANCE AND NOVEL INFORMATION

To our knowledge this is the first time this complication has been reported following SUB device placement.

Long-term results of the treatment of complex ureteral stenosis with extra-anatomic ureteral bypasses

Introduction

Complex ureteral obstruction is a pathology that has always been a challenge for the urologist, especially in patients with high surgical risk or with a short life expectancy.

Material and methods

Between 2002 and 2017, 13 extra-anatomical bypasses were placed. A descriptive retrospective study was carried out. An analysis of the permeability time of the prosthesis was performed using Kaplan-Meyer curves. Demographic and etiological characteristics as well as early and late complications were analysed.

Results

Etiologies were benign in 39% (including 3 transplant recipients) and malignant in 69%. Permeability rates were 90.9% at each of 12, 24 and 48 months, respectively, and 75.8% at 60 months. There were no deaths in the early postoperative period, nor intraoperative complications. The most frequent complications were infections. Three of them were associated with bypass extrusion, which needed to be removed. A total of 5 prosthesis had to be removed. 40% of the patients did not present complications.

Conclusions

The extra-anatomical ureteral bypass is an alternative to permanent nephrostomy in the treatment of complex ureteral strictures. Their patency rates after long-term follow-up vary from 90% to 75% at 48 and 60 months, respectively. Their complication rates can be considered acceptable in the patients’ clinical contexts.

Subcutaneous pyelovesical bypass - Detour bypass - as a solution for ureteric obstruction

Introduction

Many patients suffer from unilateral or bilateral hydronephroses caused by pelvic tumors, retroperitoneal fibrosis, occlusion due to radiation therapy or iatrogenic damage to the ureter. Currently, percutaneous nephrostomy or double J stents are primarily used. Nephrostomy deteriorates a patient’s quality of life and leads to frequent infections, blockage of tubes, or bleeding, while uretral stents are associated with septicemia and irritative bladder symptoms. Thus, a useful solution is a Detour stent.

Material and methods

A Detour stent consists of an outer layer made of polytetrafluoroethylene and an inner layer that is a silicone tube 17 F wide, with perforations on both ends and a radio-opaque ring on the proximal end. The ring allows for the insertion of the Detour to the kidney in the correct way. The Detour is placed subcutaneously to the kidney and to the bladder. The route is then tunneled by the large plastic hollow tube for inserting the Detour, and its distal end is sutured to the bladder.

Results

Twelve patients were operated using this method, one of which received a Detour stent bilaterally. The mean follow-up was 10 months. All patients were operated previously by different methods. The average time of surgery was 78 minutes. The following complications occurred: urinary tract infections, haematoma, obstructed flow of urine through the Detour stent, prolonged urinary leakage, and pyelonephritis.

Conclusions

Subcutaneous nephrovesical bypass – Detour System – is a minimally invasive, safe and effective procedure that improves quality of life with no serious complications. The Detour System allows urine to be drained in those cases where many other treatments had failed or were not feasible.

Placement of subcutaneous ureteral bypasses without fluoroscopic guidance in cats with ureteral obstruction: 19 cases (2014-2016)

Objectives The purpose of this study was to describe the perioperative and postoperative complications as well as short-term and long-term outcomes in cats with ureteral obstructions treated by placement of a subcutaneous ureteral bypass (SUB) device without imaging control. The second objective of this study was to compare cats treated by SUB device with cats treated by traditional surgical intervention. Methods Data were obtained retrospectively from the medical records (2014-2016) of cats that underwent SUB placement (SUB cats) and cats that underwent traditional ureteral surgery (C cats). Results Nineteen SUB devices were placed without fluoroscopic, radiographic or ultrasonographic guidance in 13 cats. Fifteen traditional interventions (ureterotomy and neoureterocystostomy) were performed in 11 cats. Successful placement of the SUB device was achieved in all cats with only one major intraoperative complication (kinking of the kidney catheter) and one minor intraoperative complication (misplacement of the kidney catheter). Eleven SUB cats recovered from the surgical procedure; two SUB cats and three C cats died during the anaesthesia recovery period. Postoperative SUB complications included anaemia (n = 2), urinary tract infection (UTI) (n = 4), non-infectious cystitis (n = 5) and SUB device obstruction (n = 1). Postoperative traditional surgery complications included anaemia (n = 7), UTIs (n = 6), non-infectious cystitis (n = 1), re-obstruction (n = 4) and ureteral stricture (n = 1). Median postoperative duration of hospitalisation (3 days) was significantly shorter for SUB cats than for C cats ( P = 0.013). Ten SUB cats (76.9%) and four C cats (40%) were still alive at a median follow-up of 225 days and 260 days, respectively. Owners were completely (90%) or mostly (10%) satisfied with the SUB device placement. Conclusions and relevance SUB device placement appears to be an effective and safe option for treating ureteral obstruction in cats, and this study has shown that fluoroscopic guidance is not essential in all cases.

[Subcutaneous ureteral bypass devices as a treatment option for bilateral ureteral obstruction in a cat with ureterolithiasis]

A 6-year-old female spayed Domestic Shorthair cat was presented with acute lethargy, dehydration, marked azotemia, metabolic acidosis, left-sided renomegaly, and bilateral hydronephrosis. Ureterolithiasis and ureteral obstruction were suspected based on further diagnostics including abdominal sonography. Medical treatment was not successful. Fluoroscopically guided antegrade pyelography confirmed the diagnosis of bilateral ureteral obstruction due to ureterolithiasis. Subcutaneous ureteral bypass (SUB) devices were placed bilaterally, followed by close patient monitoring. Frequent reassessment of patient parameters and blood work served to adjust the fluid needs of the patient and to ensure proper hydration, correction of azotemia at an appropriate rate, and cardiovascular stability. After significant improvement of all patient parameters within 5 days, the patient was discharged from the hospital. Treatment included a dietary change to reduce the risk of stone formation as well as a phosphorus binder. Clinical and clinicopathologic parameters were unchanged at the 1- and 4- and 7-month rechecks (consistent with IRIS CKD stage II-NP-AP0), and both SUB devices continued to provide unobstructed urine flow. Bilateral placement of subcutaneous ureteral bypass devices may be a safe and potentially effective treatment option for acute bilateral ureteral obstruction in cats with ureterolithiasis. Strict patient monitoring and patient-centered postoperative treatment decisions are crucial to successful treatment outcomes.

Subcutaneous nephrovesical bypass: Treatment for ureteral obstruction in advanced metastatic disease

The aim of the present study was to explore the value of subcutaneous nephrovesical bypass (SNVB) for the treatment of ureteral obstruction due to pelvic metastatic disease. SNVB stents (n=30) were implanted in 24 patients with advanced metastatic disease between January 2008 and December 2012. Urinalysis, serum creatinine (SCr), glomerular filtration rate (GFR), quality of life (QoL) scores, and renal ultrasonography were evaluated at follow-up. The SNVB procedures were successful in all 24 patients. Patient follow-ups occurred at an average of 10.6 months. Preoperative hydronephrosis was eliminated in 16 cases (53.3%) and reduced in the remaining patients. Following surgery, SCr levels reduced significantly from 256±46 to 124±23 μmol/l (P<0.001). GFRs increased from 25±4.8 to 45±5.3 ml/min (P<0.01). The mean QoL scores were 3.4±1.4 preoperatively and 7.6±1.0 postoperatively (P<0.001). The results showed that SNVB is a minimally invasive, effective and safe procedure for patients with ureteral obstruction resulting from advanced malignant disease. As an alternative procedure to percutaneous nephrostomy, SNVB offers patients a better QoL.

Extra-anatomic stent (EAS) as a salvage procedure for transplant ureteric stricture

Ureteric stricture is the most common urological complication following renal transplantation. Management often involves endo-urological interventions and open surgery. The definitive treatment is surgical reconstruction to restore continuity. Where this is not possible or contra-indicated and a stent cannot be placed in the ureter, an extra-anatomic stent (EAS) could be used to bypass a complete ureteric obstruction. Using an existing nephrostomy tract, a percutaneous stent is placed in the kidney and is tunneled under the skin into the bladder establishing extra-anatomical urinary drainage. We report the use of a novel EAS system in a patient with transplant ureteric stricture when antegrade stent placement or surgical reconstruction was not possible.

[Avoidance and management of complications in open surgical ureter reconstruction]

Open surgical reconstruction of the ureter is a urological procedure with a potentially high risk of complications. The correct selection of patients and time of operation are important aspects regarding the treatment strategy. Position and length of the affected ureter segment to be reconstructed determine the surgical intervention possibilities. The psoas hitch procedure is a well-established technique for distal reconstruction of the ureter where most iatrogenic injuries occur. In more proximal or complex defects, several procedures are available. Partial or complete replacement of the ureter with bowel is still considered the standard for bridging long ureteral defects but is accompanied with higher intra- and postoperative complication rates. In specific patients and situations, autotransplantation of the kidney and subcutaneous pyelovesical bypasses are clinical options. Using mucosal grafts or tissue engineering may be new therapeutic prospects to cover ureteral defects but the clinical impact still needs to be clarified. All therapeutic strategies share the fact that great surgical expertise and experience are necessary as the operative technique must be mastered to avoid severe complications.

The Detour Extra-Anatomic Stent—a Permanent Solution for Benign and Malignant Ureteric Obstruction?

OBJECTIVES

We describe our experience of the Detour extra-anatomic stent (EAS) (Mentor-Porgés, UK) for permanent bypass of complete upper urinary tract obstruction. The self-retaining expanded polytetrafluoroethylene-silicone tube, placed in the kidney using a percutaneous route, is tunnelled under the skin and sutured into the bladder to establish extra-anatomical urinary drainage.

METHODS

From April 2002 to November 2005, a total of nine Detour stents were inserted into eight patients; one patient needed bilateral stent insertions. The causes for ureteric obstruction were persistent malignant disease in three and complicated benign disease in five patients.

RESULTS

To date, four of five patients with benign disease are alive; one died unexpectedly of metastatic malignancy. The only stent-related complications were infection and haematuria. The two patients with malignancy have subsequently died, but there were no urinary drainage problems for their second and third years of life, respectively.

CONCLUSIONS

The preliminary data presented here suggest that the Detour EAS offers a permanent and minimally invasive method to establish internalisation of urinary drainage to bypass complete ureteric obstructions for which conventional stenting has failed, open surgery has been tried and failed or was not considered feasible, and long-term nephrostomy drainage was not favoured.

Nephrovesical subcutaneous ureteric bypass: long-term results in patients with advanced metastatic disease-improvement of renal function and quality of life

OBJECTIVE

Placing a percutaneous nephrostomy often is the only and final solution for patients with metastatic disease, where internal ureteral stenting proved to be impossible.

METHODS

Between August 1999 and June 2005, 31 nephrovesical ureteric bypasses were implanted in 28 patients with advanced metastatic disease. The ureteric bypass consists of two subcutaneously connected 12F polyurethane tubes, placed as a nephrostomy and cystostomy. Urinary culture, serum creatinine, quality of life score, and renal ultrasonography were evaluated at follow-up.

RESULTS

Mean follow-up was 11.9 mo (range, 2-54 mo). Preoperative hydronephrosis was eliminated in 27 cases (87.1%) and reduced in the remaining four kidneys (12.9%). Preoperative serum creatinine levels (5.9+/-3.2 mg%) decreased significantly postoperatively (1.4+/-0.9 mg%). Mean quality of life score was 3.4+/-1.4 preoperatively and 7.6+/-1.0 postoperatively. In five patients (17.9%) the system had to be replaced due to occlusion at a mean follow-up of 10.2 mo.

CONCLUSION

This nephrovesical ureteric bypass is a simple, minimally invasive, and highly effective treatment for patients with hydronephrosis resulting from advanced oncologic disease. Patients gain a better quality of life due to increased independence and mobility during their final stages of life.