Percutaneous nephrostomy and antegrade ureteral stenting: technique-indications-complications

Manual Replacement of Double J Stent Without Fluoroscopy (Double j stent replacement)

It is not always possible to replace a ureteric stent with a new one due to the fact that tumoral effect increases in ureter with time. We present our experience of manual replacement of double J stent without fluoroscopy. The data from 23 female patients who underwent double J stent replacement with a total of 110 times was retrospectively analyzed. The steps of technique are as follows: take out distal end of the double J stent through urethra to external urethral meatus cystoscopically, insert a 0.035-inch guide wire through double J stent to the renal pelvis or intra pelvicaliceal system, take out old double J stent over guide wire, slide new stent over guide wire and at external meatus level take out guide wire while gently sliding distal end of double J stent over guide wire into urethra. The mean age was 58.39 ± 9.21 years. Cervical, endometrial, and ovarian cancer were diagnosed in 16, 4, and 3 patients respectively. The mean follow-up and indwelling period were 13.8 ± 5.2, 3.8 ± 0.6 months, respectively. Increased pelvicaliceal dilatation, serum creatinine level, or renal parenchymal loss was not observed. Replacement of double J stents with this technique is easy and can be used successfully in distal ureteral obstructions.

Percutaneous ureteral stent placement for the treatment of a benign ureteral obstruction in a Sumatran tiger (Panthera tigris sumatrae)

A 15-year-old, 113 kg intact male Sumatran tiger (Panthera tigris sumatrae) was evaluated for weight loss, polydipsia, and intermittent hematuria. The tiger was immobilized for diagnostic testing including blood work, urinalysis, and abdominal ultrasound. Laboratory testing demonstrated macro- and microhematuria, azotemia, and an increased urine protein:creatinine ratio. Abdominal ultrasound revealed bilateral ureterolithiasis as well as hydronephrosis and ureteral dilation. Ultrasonography performed 5 months later revealed worsening of the right-sided hydronephrosis and hydroureter and a decrease in the severity of dilation on the left side presumably from passage of the left-sided ureteral calculi. Nephroureteral decompression via the placement of a stent was elected. A pigtail ureteral catheter (8.2 French diameter) was placed in the right ureter via an antegrade percutaneous approach utilizing ultrasound and fluoroscopic-guidance. Following stent placement, macrohematuria resolved although microhematuria was noted in opportunistic urine samples. Five months after stent placement, the azotemia had mildly progressed, the urine protein:creatinine ratio was improved, the right hydronephrosis and hydroureter had completely resolved, and the ureteral stent remained in the appropriate position. The tiger had clinically improved with a substantial increase in appetite, weight, and activity level. Ureteral stenting allowed for nephroureteral decompression in the captive large felid of this report, and no complications were encountered. Ureteral stenting provided a minimally invasive method of managing ureteral obstruction in this patient and could be considered in future cases due to the clinical improvement and low morbidity.

Percutaneous nephrostomy for symptomatic hypermobile kidney: a single centre experience

Introduction

Symptomatic hypermobile kidney is treated with nephropexy, a surgical procedure through which the floating kidney is fixed to the retroperitoneum. Although both open and endoscopic procedures have a high success rate, they can be associated with risk of complications, relatively long hospital stay and high cost.

Aim

We describe our percutaneous technique for fixing a hypermobile kidney and evaluate the efficacy of the percutaneous nephrostomy insertion in management of symptomatic nephroptosis.

Material and methods

Between January 2005 and December 2011, 11 patients diagnosed with a symptomatic right nephroptosis of at least 1 year duration were treated with a single point percutaneous nephrostomy technique. All data were retrieved from patients’ medical records and then retrospectively analysed.

Results

Nephropexy through a single point percutaneous nephrostomy technique was successfully accomplished in 11 women. The mean operative time was 20 min. The intraoperative estimated blood loss was minimal in all cases. No major or minor intraoperative complications were noted. The average postoperative hospital stay was 2 days. Women returned to their usual activities 14 days following the surgery. Nine women had complete resolution of their pain, and 2 patients continued to complain of discomfort in their lumbar area. One patient was re-operated upon with satisfactory subjective and objective outcomes achieved. One patient refused re-operation.

Conclusions

Percutaneous nephropexy is simple, inexpensive and effective for treatment of symptomatic hypermobile kidney. It remains a valuable alternative to open, laparoscopic, and robotic methods for fixing a floating kidney.

Tracked ultrasonography snapshots enhance needle guidance for percutaneous renal access: a pilot study

BACKGROUND AND PURPOSE

Although ultrasonography-guided percutaneous nephrostomy is relatively safe, a number of factors make it challenging for inexperienced operators. A computerized needle navigation technique using tracked ultrasonography snapshots was investigated to determine whether performance of percutaneous nephrostomy by inexperienced users could be improved.

METHODS

Ten operators performed the procedure on a phantom model with alternating needle guidance between conventional ultrasonography and tracked ultrasonography snapshots. The needle was reinserted until fluid backflow confirmed calyceal access. Needle trajectories were recorded using the real time needle navigation system for offline evaluation of operator performance. Recorded needle trajectories were used to measure needle motion path length inside the phantom tissue, number of reinsertions, total procedure time, and needle insertion time as end points of this study.

RESULTS

Needle path length measured inside the phantom tissue was significantly lower with ultrasonography snapshots guidance (295.0±23.1 mm, average±standard error of the mean) compared with control procedures (977.9±144.4 mm, P<0.01). This was associated with a significantly lower number of needle insertion attempts with ultrasonography snapshots (average 1.27±0.10 vs 2.83±0.31, P<0.01). The total procedure time and the needle insertion time were also significantly lower with ultrasonography snapshots guidance.

CONCLUSION

Tracked ultrasonography snapshots appear to improve the performance of percutaneous nephrostomy in these preliminary investigations, justifying further validation studies. The presented navigation system is reproducible because of commercially available hardware and open-source software components, facilitating its potential role in clinical practice.

Urologic stenting-induced trauma: a comprehensive review and case series

OBJECTIVE

To characterize traumatic injuries secondary to ureteral stent manipulation and analyze factors associated with their occurrence.

METHODS

We performed a comprehensive retrospective review of the literature and of our institutional records for occurrences of iatrogenic injury because of retrograde ureteral stent procedures.

RESULTS

Overall, 22 cases were identified, including 3 cases at our institution. Most injuries involved a major artery (52%) or vein (30%), with the remainder (17%) limited to the genitourinary tract. Associated factors included: hydronephrosis, pelvic malignancy, indwelling or chronic ureteral stents, chemoradiation, and urinary diversion.

CONCLUSION

Ureteral stenting-induced trauma is a rare but potentially life-threatening event. Recognition of the risk factors that predispose patients to iatrogenic stent trauma may help to prevent such injuries or, alternatively, it may facilitate their prompt diagnosis and treatment.

Investigating the flow dynamics in the obstructed and stented ureter by means of a biomimetic artificial model

Double-J stenting is the most common clinical method employed to restore the upper urinary tract drainage, in the presence of a ureteric obstruction. After implant, stents provide an immediate pain relief by decreasing the pressure in the renal pelvis (P). However, their long-term usage can cause infections and encrustations, due to bacterial colonization and crystal deposition on the stent surface, respectively. The performance of double-J stents - and in general of all ureteric stents - is thought to depend significantly on urine flow field within the stented ureter. However very little fundamental research about the role played by fluid dynamic parameters on stent functionality has been conducted so far. These parameters are often difficult to assess in-vivo, requiring the implementation of laborious and expensive experimental protocols. The aim of the present work was therefore to develop an artificial model of the ureter (i.e. ureter model, UM) to mimic the fluid dynamic environment in a stented ureter. The UM was designed to reflect the geometry of pig ureters, and to investigate the values of fluid dynamic viscosity (μ), volumetric flow rate (Q) and severity of ureteric obstruction (OB%) which may cause critical pressures in the renal pelvis. The distributed obstruction derived by the sole stent insertion was also quantified. In addition, flow visualisation experiments and computational simulations were performed in order to further characterise the flow field in the UM. Unique characteristics of the flow dynamics in the obstructed and stented ureter have been revealed with using the developed UM.

Laparoscopic ureterolysis and omental wrapping in patients with retroperitoneal fibrosis and obstructive uropathy: a single-center experience

OBJECTIVES

To analyze the outcomes with mid- to long-term follow-up of laparoscopic ureterolysis (LU) and omental wrapping in retroperitoneal fibrosis (RPF) with obstructive uropathy.

PATIENTS AND METHODS

Records of 9 patients with RPF who had obstructive uropathy at presentation and had undergone LU and omental wrapping at our center during January 2004 to June 2012 were collected and analyzed.

RESULTS

Six females and three males underwent LU for RPF. Underlying causes of RPF could not be found in 8 (89%) cases. Two patients underwent bilateral LU. Mean operative time and estimated blood loss were 213 minutes (range, 180-280 minutes) and 119 mL (range, 70-200 mL), respectively. No case required conversion to open surgery. The only significant intraoperative complication (1/9 [11%]) was ureteral injury, which was easily repaired intraoperatively. The postoperative complication rate was 44% (4/9). Most complications (75% [3/4]) were minor and did not need specific treatment. The mean follow-up period was 46 months (range, 4-72 months). The success rate at last follow-up was 89%.

CONCLUSIONS

Treatment of RPF is still controversial. Any future prospective randomized comparative trials seem unlikely in view of the low incidence of RPF. LU and omental wrapping in the setting of obstructive uropathy are safe and an effective alternative with a high success rate at mid- to long-term follow-up.

Cystoscopic extraction technique and external drainage rescue of a failed attempt to traverse a severe transplanted ureteral obstruction

Purpose

The aim of this research was to evaluate the efficacy of the cystoscopic extraction and external drainage techniques for unsuccessful antegrade stenting in transplanted severe ureteral obstruction.

Materials and Methods

A total of 26 patients with severe transplanted ureteral obstruction in whom the cystoscopic extraction technique and/or external drainage technique was performed were retrospectively evaluated. After the severe obstruction was successfully traversed, balloon dilatation followed by double-J stent insertion was performed.

Results

Of the 26 patients (male:female, 9:4; mean age, 38.1 years) who underwent failed ureteral stenting with the conventional procedure, 16 patients underwent successful stenting with the cystoscopic extraction technique, and 10 patients underwent successful stenting following external drainage. The mean serum creatinine of the 26 patients before stenting was 42.9 mg/dL (range, 32.7 to 54.1 mg/dL), which decreased to 10.3 mg/dL (range, 8.7 to 11.8 mg/dL) after stenting. The complications of the procedure were lower abdominal pain in 22 patients and gross hematuria in 9 patients. All complications were relieved with medical care within 3 to 5 days after the procedure. No major complications occurred.

Conclusions

The cystoscopic extraction technique and external drainage technique are safe and useful for traversing a severe transplanted ureteral obstruction after a failed conventional procedure.

Efficacy of percutaneous nephrostomy during flexible ureteroscopy for renal stone management

PURPOSE

Preoperative percutaneous nephrostomy (PCN) can be applied to urinary stone patients with pyelonephritis as well as obstructive uropathy; thus, some patients undergo flexible ureteroscopy (fURS) in the presence of a PCN tube. We evaluated the effectiveness of PCN during fURS for the management of renal stones.

MATERIALS AND METHODS

We retrospectively analyzed 130 consecutive patients who underwent fURS for renal stones between January 2009 and December 2011. All fURS procedures were performed by a single experienced surgeon. The patients were divided into two groups depending on the presence of PCN during the surgery: patients with PCN (group 1, n=41) and patients without PCN (group 2, n=89). To evaluate operative outcomes, we compared success rates, operative times, and complication rates. We defined success as the absence of any residual stones in the kidney or stone fragments less than 2 mm that were too small to be extracted during follow-up.

RESULTS

There were no significant differences in age, sex, body mass index, stone laterality, burden, or location between the two groups. The mean operative times of groups 1 and 2 were 50.1 and 58.3 minutes, respectively (p=0.102). The success rates of groups 1 and 2 were 95.1% and 82.0%, respectively (p=0.044). There was no statistically significant difference in the complication rate between groups 1 and 2 (p=0.888).

CONCLUSIONS

Flexible ureteroscopy in the presence of PCN produced a superior outcome in terms of the success rate without increasing the operative time or complication rate. PCN may be helpful to induce better outcomes of fURS.

An artificial model for studying fluid dynamics in the obstructed and stented ureter

Fluid dynamics in the obstructed and stented ureter represents a non-trivial subject of investigation since, after stent placement, the urine can flow either through the stent lumen or in the extra-luminal space located between the stent wall and the ureteric inner wall. Fluid dynamic investigations can help understanding the phenomena behind stent failure (e.g. stent occlusions due to bacterial colonization and encrustations), which may cause kidney damage due to the associated high pressures generated in the renal pelvis. In this work a microfluidic-based transparent device (ureter model, UM) has been developed to simulate the fluid dynamic environment in a stented ureter. UM geometry has been designed from measurements on pig ureters. Pressure in the renal pelvis compartment has been measured against three variables: fluid viscosity (μ), volumetric flow rate (Q) and level of obstruction (OB%). The measurements allowed a quantification of the critical combination of μ, Q and OB% values which may lead to critical pressure levels in the kidney. Moreover, an example showing the possibility of applying particle image velocimetry (PIV) technology to the developed microfluidic device is provided.

Efficacy of percutaneous nephrostomy tube during ureteroscopy for upper ureter stone management

OBJECTIVE

Preoperative percutaneous nephrostomy (PCN) has been commonly performed for patients with urinary stones complicated with pyelonephritis or obstructive uropathy; in fact, a considerable number of patients undergo ureteroscopic removal of stone (URS) in the presence of a PCN. We assessed the effectiveness of PCN during URS in the management of upper ureteral stones.

PATIENTS AND METHODS

We retrospectively analyzed 140 patients who underwent URS for upper ureteral stones between January 2008 and December 2011. All URS were performed by a single experienced surgeon. The subjects were divided into two groups depending on the presence of a PCN at the time of the surgery (PCN group: 42 and non-PCN group: 98). The PCN group was subdivided into two groups depending on the performance of external fluid irrigation through PCN during the surgery (irrigation group: 21 and non-irrigation group: 21). To evaluate operative outcomes, we compared operative times, auxiliary procedures required, and success and complication rates.

RESULTS

The PCN group showed significantly better outcomes in terms of the operative time (57.4 minute vs. 68.1 minute) and success rate (92.9% vs. 78.6%) without increasing the complication rate. In the PCN group, the irrigation group showed a shorter operative time compared to the non-irrigation group, although statistical significance was not observed. Other perioperative outcomes, such as the success rate, auxiliary procedures, and complication rates, were not significantly different between the two groups.

CONCLUSION

URS for upper ureteral stones in patients with PCN produced superior surgical outcomes in terms of the success rate, operative time, and auxiliary procedure rate without increasing the complication rate. The presence of PCN with/without external irrigation during URS can be a beneficial factor to produce better outcomes of URS for the management of upper ureteral stones.

Efficacy and complications of urinary drainage procedures in idiopathic retroperitoneal fibrosis complicated by extrinsic ureteral obstruction

OBJECTIVE

To investigate the efficacy and complications of urinary drainage procedures in patients with idiopathic retroperitoneal fibrosis complicated by ureteral obstruction.

METHODS

A retrospective study of 30 idiopathic retroperitoneal fibrosis patients involving 44 obstructed urinary units who underwent urinary drainage from January 2002 through April 2010 was carried out. Data of all diagnostic procedures, blood and urine cultures, and hospital admissions were collected and analyzed.

RESULTS

In 12 of 44 (27%) cases, percutaneous nephrostomy was carried out at the first step. Attempted ureteral stenting at the first step was successful in 25 of 32 (79%) cases, of which 20 (80%) cases could be managed successfully by ureteral stenting alone throughout the study period. Successful prolonged urinary drainage with percutaneous nephrostomy alone was accomplished in 10 cases, three at the first step and seven at the second step after failed intraureteral stent insertion or after unsuccessful maintenance of urinary drainage with an intraureteral stent. A total of 21 urinary tract infection episodes occurred in 11 patients. The incidence and accumulated incidence of acute pyelonephritis was 0.062 episodes/100 person-days and 30%, respectively. The incidence and accumulated incidence of urosepsis was 0.015 episodes/100 person-days and 6.6%, respectively. The overall number of complications did not differ between external and internal urinary drainage procedures (percutaneous nephrostomy, 21% vs intraureteral stent, 17.9%; P = 0.79).

CONCLUSION

Both intraureteral stent and percutaneous nephrostomy placement are a safe way to relieve urinary obstruction in idiopathic retroperitoneal fibrosis patients, and they have comparable complication rates. Over time, the need for using both management options in the same patient might be required. Hence, these techniques should be regarded as complementary.

Radiation-free percutaneous nephrostomy performed on neonates, infants, and preschool-age children

AIM

The aim of this study was to evaluate the effectiveness and safety of high-frequency linear probe ultrasonographic (US) guidance percutaneous nephrostomy (PN) in terms of diagnostic and therapeutic approach in preschool-age children with urological problems.

MATERIALS AND METHODS

PN was performed on 40 kidneys in 33 patients (13 girls, 20 boys) aged 3 days - 7 years (mean 4.1 years). All procedures were performed with US guidance utilizing a Shimadzu SDU 2200 Xplus 5-10 mHz probe. Complete blood count, urinalysis, bladder urine culture, blood urea, and creatinine values were obtained before PN placement on the same day. Urine cultures were obtained by nephrostomy tube and compared to bladder urine culture.

RESULTS

PN procedures were technically successful in 39 kidney units (97.5%). Two major complications were macroscopic hematuria requiring blood transfusions (1 case) and sepsis (1 case). Minor complications were displacement of the catheter (4), urinary tract infection (4), urine extravasation (1), early dislocation of the catheter (1). In three cases, the catheter was replaced. Analysis of bladder urine showed that 13 patients (39.4%) had positive cultures, but analysis of PN urine showed that 25 patients (78.1%) had positive cultures.

CONCLUSIONS

PN is an easy, safe and efficient diagnostic and therapeutic procedure with few complications even in preschool-age children. The antibiotic regimen should be revised in order to avoid sepsis and urinary tract infection.

[Diagnostic puncture of the renal pelvis: avoidance of urinary diversion in cases of hydronephrosis and non-specific fever]

INTRODUCTION

There are individual cases especially of elderly or palliative patients with hydronephrosis and non-specific fever where a urinary diversion should be avoided in favor of quality of life. For these purposes this study presents the method and the results obtained with a diagnostic puncture of the renal pelvis.

METHODS

Demographic data, indications for urinary diversion and the disease leading to hydronephrosis were retrospectively recorded from the operation reports of all percutanous nephrostomy procedures from 2007 to 2012. All cases in which a diagnostic puncture of the renal pelvis was conducted to potentially avoid placing a nephrostomy tube were considered separately.

RESULTS

From January 2007 to May 2012 a total of 476 percutanous nephrostomies were accomplished in this department. The most frequent indication for nephrostomy was acute renal failure in 55.3% of cases followed by septic laboratory constellations (33.1%) and colic (10.9%). Of the 148 cases of hydronephrosis combined with sepsis, a diagnostic puncture of the renal pelvis was accomplished in 20.1%. In these cases the hydronephrosis had an underlying urological origin in 71.0%, reaching statistical significance with reference to the complete collective (p=0.034). In 21 out of 34 nephrology units (61.8%) it was possible to avoid nephrostomy due to clear urine and immediate urinanalysis without any evidence for infection. In the other cases a nephrostomy tube was placed.

CONCLUSIONS

Using a diagnostic puncture of the renal pelvis a nephrostomy could be avoided in over 50% of cases with a combination of hydronephrosis and non-specific fever in favor of quality of life.

Nephroureteral stents: principles and techniques

Nephroureteral stents including antegrade, retrograde, or internal (double-J) stents are routinely placed by interventional radiologists. The purpose of this review is to provide a detailed and comprehensive description of indications, contraindications, technique, and various technical challenges of these procedures. Also pre- and postprocedure management of patients will be discussed including routine follow-up and dealing with potential complications.

Nephrostomy tube related pyelonephritis in patients with cancer: epidemiology, infection rate and risk factors

PURPOSE

Nephrostomy tube placement is often necessary to avert acute renal failure in patients with cancer with obstructive uropathy or in patients with ureteral leak. However, there have been limited published studies on the rate and risk of nephrostomy tube related pyelonephritis in patients with cancer. Therefore, in this study we determined rates of nephrostomy tube related pyelonephritis and predisposing risk factors in patients with cancer.

MATERIALS AND METHODS

We retrospectively reviewed patients who underwent nephrostomy tube placement between September 1, 2009 and September 16, 2010 at MD Anderson Cancer Center. Patients were followed for 90 days. The primary outcome assessed was the development of nephrostomy tube related pyelonephritis and the secondary outcome was the development of asymptomatic bacteriuria. We also determined risk factors associated with pyelonephritis.

RESULTS

Of the 200 patients analyzed 38 (19%) had pyelonephritis and 15 (7.5%) had asymptomatic bacteriuria. Of the nephrostomy tube related infections 34 cases (89%) were with the primary nephrostomy tube. Subsequently 4 of the patients who underwent nephrostomy tube exchange had an episode of pyelonephritis. Pyelonephritis developed within the first month in 19 (10%) patients. Prior urinary tract infection and neutropenia were found to be significant risk factors for pyelonephritis (p = 0.047 and 0.03, respectively).

CONCLUSIONS

The placement of nephrostomy tubes in patients with cancer is associated with a significant rate of pyelonephritis. Neutropenia and history of urinary tract infection were significant risk factors for pyelonephritis. This finding warrants further investigation into preventive strategies to reduce the infection rate.

[A different approach to the percutaneous nephrostomy by urologists]

INTRODUCTION

Percutaneous nephrostomy (PCN) tube placement is generally performed in radiologic departments worldwide. However, there are a few urologist-directed studies about PCN performed with ultrasound guidance. Needle direction using a convex abdominal ultrasound probe might be difficult in unexperienced hands. In order to perform this procedure easily, we propose that a probe placed on flank or intercostal region and a long grooved needle director that never allows needle movement would be useful. We considered a transrectal ultrasound (TRUS) probe was suitable to resolve this issue.

MATERIAL AND METHOD

From January 2007 to April 2011, a total of 113 percutaneous renal access (PRA) were performed using a TRUS probe in 102 patients, aged 20 to 84 years old. Because of the insufficient imaging capability of the TRUS probe in obese patients whose body mass index (BMI) greater than 30kg/m(2) were excluded. Forty two PRA were performed under local anesthesia and this group was named local anesthesia (LA) group. Seventy one PRA were performed for nephrostomy insertion under local anesthesia supplemented by deep sedation and this cluster was named deep sedation (DS) group.

RESULTS

Targeted calyx puncture and guide wire placement was performed in all patients (100%) but success rate of tube insertion in each group was different. Successful PCN insertion rate was 69.1% (29 of 42 cases) in LA group and 95.8% (68 of 71 cases) in DS group. No major vascular injury and/or adjacent organ injury to bowel, liver, spleen or lung was seen in any patient.

CONCLUSION

Guidance of TRUS probe, deep sedation, and modified dilators may offer a high success rate to the urologists with little experience in PCN insertion which they would find it difficult to perform.

Non-elective percutaneous nephrostomy (PCN) service in a tertiary uroradiology centre: can radiologists and urologists agree on timing?

AIM

To assess agreement between uroradiologists and urologists with regards to the timing of non-elective percutaneous nephrostomy (PCN) catheter insertion, and whether any delay produced unacceptable complications.

MATERIALS AND METHODS

Standardized data collection forms detailing patient demographics, indications for PCN catheter insertion, blood results, procedural details, and immediate complications were completed by uroradiologists. At the time of referral, patients were stratified by both radiologists and urologists into three groups as follows: group 1 = PCN within 6 h; group 2 = PCN between 6 and 24 h; and group 3 = PCN between 24 and 48 h.

RESULTS

One hundred and eighteen non-elective PCN catheter insertions were performed over 2 years. Radiologists stratified 12 patients (10.2%) into group 1, 65 (55.1%) patients into group 2, and 41 (34.7%) patients into group 3. Urologists stratified 14 (11.9%) patients into group 1, 68 (57.6%) patients into group 2, and 36 (30.5%) patients into group 3. There was good agreement between radiologist and urologists (κ = 0.865) on stratification in all but nine (7.6%) cases. Ninety-four point one percent of PCN catheters were inserted within the timeframe stratified by radiologists and urologists, or sooner. Sepsis was associated with a shortened timeframe. Elevated international normalized ratio (INR; >1.5) resulted in an increased timeframe. A major complication rate of 3% is within recommended limits. Fourteen percent of PCN catheter insertions were inserted outside normal working hours. Urgency stratification has decreased the number of cases performed out of hours.

CONCLUSION

Radiologists and urologists had good agreement on stratification with an acceptable major complication rate of 3%.

Prophylactic antibiotic guidelines in modern interventional radiology practice

Modern interventional radiology practice is continuously evolving. Developments include increases in the number of central venous catheter placements and tumor treatments (uterine fibroid therapy, radio- and chemoembolization of liver tumor, percutaneous radiofrequency and cryoablation), and new procedures such as abdominal aortic aneurysm stent-graft repair, vertebroplasty, kyphoplasty, and varicose vein therapies. There have also been recent advancements in standard biliary and urinary drainage procedures, percutaneous gastrointestinal feeding tube placement, and transjugular intrahepatic portosystemic shunts. Prophylactic antibiotics have become the standard of care in many departments, with little clinical data to support its wide acceptance. The rise in antibiotic-resistant strains of organisms in all hospitals worldwide have forced every department to question the use of prophylactic antibiotics. The authors review the evidence behind use of prophylactic antibiotics in standard interventional radiology procedures, as well as in newer procedures that have only recently been incorporated into interventional radiology practice.

Experience with the diagnosis and management of symptomatic ureteric stones during pregnancy

OBJECTIVE

To present our experience to describe diagnosis and management of symptomatic ureteric stones during pregnancy.

MATERIALS AND METHODS

Thirty-six pregnant women with symptomatic ureteric stones were evaluated in this study. The diagnosis was done by history, physical examination, symptoms, signs, ultrasonography, or ureteroscopy if needed. Initially, conservative management was performed on all patients. When conservative treatment failed, temporizing therapies (double-J stenting or percutaneous nephrostomy [PCN]) and (ureteroscopic lithotripsy) URSL were performed on the patients.

RESULTS

In 25 (69.4%) of the patients, ureteric stones was diagnosed on US. In the other 11 (30.6%) of the patients, definitive diagnosis was done by ureteroscopy in 5, and 6 of them passed their stones spontaneously. Conservative management was successful in 24 of 36 (66.6%) the patients. Temporizing therapies and URSL were required in 12 of 36 (33.4%) patients. A double-J stent was successfully placed in only 3 (8.3%) of the patients, and URSL was performed in 9 (25%). In 1 (2.7%) patient, PCN was performed because of persistent renal colic, fever, and pyonephrosis. In this patient, URSL was performed after symptoms and signs resolved, and then the percutaneous tube was removed.

CONCLUSION

If ultrasonography fails, ureteroscopy may be an alternative approach for definitive diagnosis. When conservative approach fails, URSL may be a good alternative approach for definitive treatment.

Anchoring system-assisted coil tract embolization: a new technique for management of arterial bleeding associated with percutaneous nephrostomy

Anchoring system-assisted coil tract embolization (AACTE), a new nonvascular treatment technique for massive bleeding associated with percutaneous nephrostomy (PCN), consists of packing the tract with embolization coils, with a balloon catheter used as an anchoring system. After arterial bleeding associated with PCN was successfully treated with AACTE in three patients, no severe complications were noted, and renal function was not affected. AACTE is a potentially useful and safe method for management of vascular complications associated with nephrostomy.

Reinforcement for percutaneous nephrostomy tubes with a new technique

BACKGROUND AND PURPOSE

Percutaneous nephrostomy (PCN) still plays a significant role in decompressing the renal collecting system. Percutaneous nephrostomy tubes (PNTs), however, which are flexible and may not be protected well by patients, are vulnerable to mechanical drag, although they are carefully fixed to the skin with silk suture. We developed a simple method to reinforce the nephrostomy tube against dislodgement from the skin.

PATIENTS AND METHODS

A total of 133 adult patients underwent ultrasonography-guided PCN; 85 patients received a conventional method to fix the tubes, while the other 48 patients received a new one. We used a rubber drainage tube, about 2 cm long, sheared longitudinally, as the outer tube to encase the nephrostomy tube, and then sutured the cutting edges together with the skin suture to reinforce the nephrostomy tube.

RESULTS

Compared with the 85 patients who received the conventional method, there was not any tube dislodgement after PCN in the 48 patients who received the new one at the end of 2 weeks (0 vs 7, P=0.049) and 4 weeks (0 vs 10, P=0.014) follow-up.

CONCLUSIONS

This is a simple, effective, and inexpensive method that can significantly decrease the dislodgement incidence of PNTs and keep them fixed well after surgery.

Percutaneous nephrostomy: native and transplanted kidneys

Percutaneous nephrostomy is a procedure in which access to the renal collecting system of a native (nontransplanted) or transplanted kidney is obtained through the skin, providing external drainage and/or a portal for additional minimally invasive procedures. Such additional minimal invasive procedures include nephrolithotripsy, ureteric stent placement, ureteric dilation, ureteric embolization/obliteration, and rendezvous procedures with cystoscopy. Percutaneous nephrostomy has been proven to be an effective and safe minimally invasive image-guided procedure. This article discusses the indications, techniques, imaging guidance modalities, and outcomes related to percutaneous nephrostomy. Extensions of the nephrostomy procedures, such as ureteric stent placement and nephro-ureteral stent placement are discussed in subsequent articles in this issue.

Cutting-balloon angioplasty of resistant ureteral stenosis as bridge to stent insertion

Ureteral stenting is a routine, minimally invasive procedure performed for relief of benign or malignant obstruction. In case of ureteral stenosis, to allow a correct insertion of the stent, a predilatation of the ureter stenosis with a conventional balloon catheter can be necessary. In exceptional cases, it can be difficult to advance an 7-8 Fr JJ-catheter over a tight resistant ureter stenosis following unsuccessful high-pressure balloon dilatation. In the present report, we describe two cases of resistant ureter stenosis successfully dilated by a cutting-balloon following the failure of high-pressure balloon dilatation, allowing a correct and uncomplicated antegrade stent insertion.

Persistent chronic peri-aortitis (‘inflammatory aneurysm’) after abdominal aortic aneurysm repair: systematic review of the literature

Abstract

Data on the outcome of aneurysmal chronic peri-aortitis (‘inflammatory aneurysm’) after open surgical aneurysm repair are few and contradictory. To what extent this inflammatory process is reversed after endovascular aneurysm repair (EVAR) is even more unclear. The objective of this review was to study the outcome of peri-aortic fibrosis (PAF) and ureteral obstruction in patients with aneurysmal chronic peri-aortitis treated with open surgery or EVAR. Medical literature was searched for pertinent articles on the outcome of PAF and ureteral obstruction after open surgery or EVAR from 1970 through October 2007. Studies were included if specific follow-up data were available on outcomes of interest. A total of 19 studies were included comprising 478 patients (open surgical, n = 426; EVAR, n = 52). Age, sex and percentage of patients with ureteral obstruction (31% vs 37%) did not differ between groups. Regression of PAF occurred more frequently after open surgery compared to EVAR (86% vs 60%; p < 0.0001). Complete regression of PAF was more frequent after open surgery compared to EVAR (52% vs 14%; p < 0.0001). After excluding patients in whom concurrent ureterolysis was performed, the frequency of persistent ureteral obstruction remained lower in patients treated surgically compared to patients treated with EVAR, albeit not statistically significant (32% vs 56%; p = 0.09). In conclusion, although open surgery is superior to EVAR in achieving regression of chronic peri-aortitis, the frequency of persistent PAF and/or ureteral obstruction is not negligible. Additional medical and/or urological treatment should be considered in selected cases of aneurysmal chronic peri-aortitis.

Is the routine check nephrostogram following percutaneous antegrade ureteric stent placement necessary?

Our aim was to review our experience with percutaneous antegrade ureteric stent (PAUS) placement and to determine if the routinely conducted check nephrostogram on the day following ureteric stent placement was necessary. Retrospective review of patients who had undergone PAUS placement between January 2004 and December 2005 was performed. There were 83 subjects (36 males, 47 females), with a mean age of 59.9 years (range, 22-94 years). Average follow-up duration was 7.1 months (range, 1-24 months). The most common indications for PAUS placement were ureteric obstruction due to metastatic disease (n = 56) and urinary calculi (n = 34). Technical success was 93.2% (96/103 attempts), with no major immediate procedure-related complications or mortalities. The Bard 7Fr Urosoft DJ Stent was used in more than 95% of the cases. Eighty-one of 89 (91.0%) check nephrostograms demonstrated a patent ureteric stent with resultant safety catheter removal. Three check nephrostograms revealed distal stent migration requiring repositioning by a goose-snare, while five others showed stent occlusion necessitating permanent external drainage by nephrostomy drainage catheter reinsertion. Following PAUS placement, the serum creatinine level improved or stabilized in 82% of patients. The serum creatinine outcome difference between the groups with benign and malignant indications for PAUS placement was not statistically significant (p = 0.145) but resolution of hydronephrosis was significantly better (p = 0.008) in patients with benign indications. Percutaneous antegrade ureteric stent placement is a safe and effective means of relief for ureteric obstruction. The check nephrostogram following ureteric stent placement was unnecessary in the majority of patients.