Search PubMed⌕ Search

Biomedical subjects

R C Rink

Publications and source records attributed to R C Rink.

At least 19 recordsLinked to original sources

What is the need for additional bladder surgery after bladder augmentation in childhood?

PURPOSE: Bladder augmentation has revolutionized the care of children with a neuropathic bladder but it remains a major surgical procedure. However, the need for subsequent bladder surgery has not been well defined in a large series with long-term followup. MATERIALS AND METHODS: We retrospectively reviewed the records of the first 500 bladder augmentations performed from 1978 to 2003 at our institution. Charts were reviewed for complications requiring additional surgery, including malignancy, bladder perforation, repeat augmentation, bowel obstruction and bladder calculi. Mean and median followup was 13.3 years. RESULTS: Complications occurred in 169 patients (34%) resulting in a total of 254 surgeries. The cumulative risk of further surgery at the bladder level was 0.04 operations per patient per year of augmentation. Three patients (0.6%) had transitional cell carcinoma, of whom all presented with metastatic disease and died. Bladder perforation occurred in 43 patients (8.6%) with a total of 53 events. Of the patients 16 (3.2%) required laparotomy for bowel obstruction and 47 (9.4%) required repeat augmentation. Bladder stones were treated in 75 patients (15%), who required a total of 125 surgeries. CONCLUSIONS: Bladder augmentation provides immeasurable improvements in quality of life but it requires lifelong dedication from the patient, family and health care providers. While the requirements for additional surgery are not trivial, 66% of our patients have not required any further surgery in the augmented bladder.

Child↗

Total continence reconstruction: a comparison to staged reconstruction of neuropathic bowel and bladder.

PURPOSE: Surgical treatment for neuropathic bowel and bladder has become an essential tool in maximizing the quality of life in patients with myelomeningocele. We present our results comparing results in patients who underwent total continence reconstruction of the urinary and gastrointestinal tracts to patients who underwent a separate or single operation. MATERIALS AND METHODS: We performed a retrospective chart review of all patients with myelomeningocele at our institution who underwent reconstruction with a cutaneous catheterizable urinary channel or Malone antegrade continence enema. We compared outcomes with regard to surgical revisions of the channel between patients who underwent the construction of each simultaneously, that is total continence reconstruction, to outcomes in those with a single channel or who underwent reconstruction at 2 or more operations. RESULTS: Most of our patients underwent genitourinary and gastrointestinal reconstruction, and few desired surgical intervention for only a single system. We were unable to find any differences in the continence rate or stomal complications. However, patients who underwent staged reconstruction usually had significant secondary reasons for repeat surgery. CONCLUSIONS: Surgical success for urinary and fecal continence can be safely and effectively achieved through single or multiple procedures. However, because of shared pathophysiology, we believe that most patients benefit from intervention in the gastrointestinal and the genitourinary tract. Therefore, a major advantage of total continence reconstruction is avoidance of the morbidity of a second major surgical procedure.

Child↗

Treatment of the occult tethered spinal cord for neuropathic bladder: results of sectioning the filum terminale.

PURPOSE: Occult tethered cord syndrome applies to patients with signs and symptoms consistent with a caudal spinal cord malformation despite normal neuroimaging. Although several reports of successful surgical treatment exist, controversy remains with respect to patient selection and efficacy. We present a large series with excellent clinical followup, neuroimaging and urodynamic characterization. MATERIALS AND METHODS: We present our experience with 36 patients at a single institution with preoperative clinical findings, neuroimaging and urodynamics available. Postoperative outcomes were assessed clinically and with urodynamics. We determined predictive parameters to improve patient selection. RESULTS: Approximately 0.04% of pediatric urology clinic visits resulted in neurosurgical referral for the potential of an occult tethered cord. They occurred after failure of a mean of 2 years of aggressive medical management. Daytime urinary incontinence was present in 83% of patients and 47% had encopresis. Preoperative urodynamics were markedly abnormal in all patients with mean bladder capacity 55% of expected capacity. Clinical improvement in urinary symptoms was seen in 72% of patients with resolution of incontinence in 42%. Bowel symptoms improved in 88% of cases, including resolution of encopresis in 53% within 3 months of surgery. Urodynamic improvements were demonstrated in 57% of cases. We were unable to determine preoperative factors that were more likely associated with surgical success. CONCLUSIONS: In a highly select population with severe urinary and fecal dysfunction sectioning a normal-appearing filum terminale can result in significant improvement. We were unable to identify factors that may increase the chance of surgical success.

Adolescent↗

Use of the mobilized sinus with total urogenital mobilization.

PURPOSE: The surgical treatment of urogenital sinus anomalies has undergone significant advances in recent years. Total urogenital mobilization, which mobilizes the urogenital sinus, vagina and urethra en bloc toward the perineum, represents one of these advances. MATERIALS AND METHODS: We have improved our results with total urogenital mobilization by incorporating the mobilized urogenital sinus tissue into the repair rather than discarding it, as described originally. We have found this a readily available, easily manipulated and well vascularized flap that is a significant aid to reconstruction. RESULTS: We present our 3 favored means of using the mobilized sinus tissue to create a mucosa lined vestibule, a posterior vaginal wall flap and an anterior vaginal wall flap. CONCLUSIONS: We believe that our techniques result in a further advancement in the cosmetic and surgical outcomes in these patients, and are beneficial in the reconstructive surgery armamentarium.

Adrenal Hyperplasia, Congenital↗

Spontaneous bladder perforations: a report of 500 augmentations in children and analysis of risk.

PURPOSE: The spontaneous perforation of an augmented bladder is an uncommon but serious complication. To our knowledge our institution has the largest reported series of bladder augmentations. We examined our data to determine the incidence of spontaneous bladder perforation and to delineate associated risk factors. MATERIALS AND METHODS: We performed a retrospective chart review of 500 bladder augmentation procedures performed during the preceding 25 years with a minimum followup of 2 years. RESULTS: Spontaneous perforations occurred in 43 patients (8.6%), for a total of 54 events. The calculated risk was 0.0066 perforations per augmentation-year at risk. Approximately a third of the cases had perforated within 2 years of surgery, a third between 2 and 6 years postoperatively, and a third at more than 6 years after augmentation. Patients who underwent augmentation between 1997 and 2003 had a higher rate of perforation within 2 years of surgery than those operated on between 1978 and 1987. Increased risk of perforation was observed with the use of sigmoid colon and bladder neck surgery. A decreased risk was associated with the presence of a continent catheterizable channel. CONCLUSIONS: We believe that this large and comprehensive series gives valuable insight into this serious complication. The delineation of these potential risk factors serves as a guide for further discussion and investigation.

Child↗

Mitrofanoff channel survival after pedicle ligation.

In patients who have undergone complex genitourinary reconstruction, additional abdominal surgery is often required. We report 2 cases in which the blood supply to an existing Mitrofanoff channel was divided. In both cases, the conduits appeared to remain well perfused, presumably based on collateral blood supply. Both conduits remained healthy and functioning at more than 1 year of follow-up.

Appendix↗

TNF-alpha mediates obstruction-induced renal tubular cell apoptosis and proapoptotic signaling.

Obstruction of the upper urinary tract induces a progressive loss in renal mass through apoptotic renal cell death. Although TNF-alpha has been implicated in ischemia-reperfusion-induced apoptotic renal cell death, its role in obstructive renal cell apoptosis remains unknown. To study this, male Sprague-Dawley rats were subjected to left unilateral ureteral obstruction vs. sham operation. Twenty-four hours before surgery and every 84 h thereafter, rats received either vehicle or a pegylated form of soluble TNF receptor type 1 (PEG-sTNFR1). The kidneys were harvested 1, 3, or 7 days postoperatively, and tissue samples were subsequently analyzed for TNF-alpha (ELISA, RT-PCR), Fas ligand (RT-PCR), apoptosis (TUNEL, ELISA), and caspase 8 and 3 activity (Western blot). Renal obstruction induced increased tissue TNF-alpha and Fas ligand mRNA levels, TNF-alpha protein production, apoptotic renal tubular cell death, and elevated caspase 8 and 3 activity, whereas treatment with PEG-sTNFR1 significantly reduced obstruction-induced TNF-alpha production, renal tubular cell apoptosis, and caspase activity. PEG-sTNFR1 did not significantly alter Fas ligand expression. These results demonstrate that TNF-alpha mediates obstruction-induced renal tubular cell apoptosis and proapoptotic signaling and identify TNF-alpha neutralization as a potential therapeutic option for the amelioration of obstruction-induced renal injury.

Animals↗

Use of the silastic sheath in bladder neck reconstruction.

OBJECTIVE: The study compared two populations of patients undergoing bladder neck reconstruction using the silastic sheath in two major pediatric centers. The success with this technique was markedly different in the two centers. The purpose of the study was to determine factors that might explain the divergent results. PATIENTS AND METHODS: Fifteen patients treated in Indianapolis were compared with 94 patients treated in London with the silastic sheath technique of bladder neck reconstruction. Eighty-seven percent of the Indianapolis patients had myelomeningocele whereas 86% of the London group had exstrophy/epispadias. Median age of the Indianapolis patients was 11 years whereas it was 8.4 years in London. Seventy-three percent of patients in Indianapolis were female and 79% in London were male. Patients were followed for a minimum of eight years in Indianapolis and a mean of seven years in London. Similar surgical technique was employed in the two centers but, over time, the London approach included use of a non-reinforced silastic wrapped loosely around the bladder neck with the interposition of omentum. RESULTS: Both groups achieved continence rates exceeding 90%. Of the Indianapolis patients, two-thirds experienced erosion of the silastic at a mean of 48 months. With modifications in the London technique, the erosion rate of silastic was lowered from 100% to 7%. CONCLUSION: Direct, snug wrap of silastic without omentum around the Young-Dees tube as well as simultaneous bladder augmentation placed patients at increased risk for erosion. The silastic sheath technique may be less applicable to myelomeningocele patients. It seems most applicable to older male patients with exstrophy or epispadias undergoing Young-Dees bladder neck reconstruction who have the ability to void.

Child↗

Cecal volvulus: a report of two cases occurring after the antegrade colonic enema procedure.

BACKGROUND: Many children with chronic constipation and fecal incontinence have benefited from the antegrade colonic enema (ACE) procedure. Routine antegrade colonic lavage often allows such children to avoid daytime soiling. This report describes 2 children in whom the ACE procedure was complicated by a cecal volvulus. METHODS: A retrospective review of 164 children with an ACE procedure was conducted. Two instances of cecal volvulus were identified. RESULTS: The first child presented with abdominal pain and difficulty intubating the ACE site. Over the subsequent day, his pain worsened, and radiographs depicted a colonic obstruction. At laparotomy, a cecal volvulus resulting in bowel necrosis was observed, and resection of the affected bowel and appendix (in the right lower quadrant) and end ileostomy was required. He subsequently had the stoma closed and a new ACE constructed with a colon flap. The second child presented with shock and evidence of an acute abdomen. At laparotomy, a cecal volvulus was noted, and ileocolic resection including the ACE stoma (located at the umbilicus) and an ileostomy and Hartmann pouch was performed. He had a protracted hospital course requiring ventilator and inotropic support. He currently is well and still has an ileostomy stoma. CONCLUSIONS: A high index of suspicion for a potentially life-threatening cecal volvulus should be maintained in children undergoing an ACE procedure who present with abdominal pain, evidence of bowel obstruction, or difficulty in advancing the ACE irrigation catheter.

Anus, Imperforate↗

Experience with non-cycled artificial urinary sphincters.

OBJECTIVE: To report our experience in children and adolescents with a non-cycled artificial urinary sphincter. While some children with the AUS can void, others require clean intermittent catheterization (CIC) through the sphincter or an alternative site for catheterization; in some of the latter we have either not cycled (pumped) an activated AUS or the AUS has failed, and there is concern about ischaemia in some adults with a non-cycled AUS. PATIENTS AND METHODS: In all, 143 patients who had an AUS placed between 1980 and 2002 were reviewed retrospectively; 15 (10 boys and five girls) no longer cycled (pumped) their AUS. The mean age at AUS insertion was 11 years and the mean (range) follow-up after insertion was 10.4 (1.64-22.2) years. The diagnoses included myelomeningocele in 11, sacral agenesis in three and cloaca in one. Nine patients have an activated functioning AUS and in six the AUS does not function; in the first nine the sphincter has not routinely been cycled (pumped) for a mean (range) of 1.6 (0.6-2.9) years. In the other six with a nonfunctioning AUS the mean (range) observation period is 6.4 (1.5-10) years since the system has not functioned. RESULTS: All patients were completely continent, including the six with a nonfunctioning AUS. After inserting the AUS, two patients voided in combination with CIC (one each urethral and abdominal stoma) and 13 emptied by CIC (nine abdominal stoma, four urethral). There was a mechanical complication in eight patients; three had the AUS repaired and are dry, and five are dry with no repair. In one patient the AUS was never activated. To date there has been no erosion of the cuff in any of the 15 patients with a non-cycled AUS. CONCLUSION: The AUS remains an extremely reliable procedure to achieve continence in children and young adults. It is versatile and can be combined with other procedures that provide an alternative means for catheterization. While some have noted the need to routinely cycle the AUS to prevent erosion, this has not been our experience in these 15 patients.

Adolescent↗

Shunt infection and malfunction after augmentation cystoplasty.

PURPOSE: Maintenance of a sterile intraperitoneal environment is critical in patients with ventriculoperitoneal shunts. Recent series have reported a broad discrepancy in the rate of shunt infection (0% to 20%) following augmentation cystoplasty. The need for distal shunt revision has not been well defined. We report the incidence of shunt infection and revision at our institution after bladder augmentation. MATERIALS AND METHODS: We retrospectively reviewed the records of all patients with myelodysplasia and a ventriculoperitoneal shunt who underwent augmentation cystoplasty since August 1990. All patients included in the study had a minimum of 12 months of followup. RESULTS: A total of 55 patients with a ventriculoperitoneal shunt secondary to myelodysplasia required augmentation cystoplasty for management of a neuropathic bladder. Standard perioperative intravenous and oral antibiotic preparation, mechanical bowel preparation and intraoperative shunt isolation were used. Mean postoperative followup was 60.4 months (range 12 to 111). One patient presented with an extruded peritoneal shunt tip and positive cultures from cerebrospinal fluid and urine. Bladder perforation occurred in 2 patients and the shunt was empirically externalized. Revision was required for 5 (9%) distal shunt obstructions, including 1 cerebrospinal fluid pseudocyst. CONCLUSIONS: The incidence of shunt infection after augmentation cystoplasty is low (less than 2% in this large series), and presence of a ventriculoperitoneal shunt should not preclude bladder augmentation. Meticulous perioperative and intraoperative preparation contributes to the low rate of adverse events. Although the rate of distal revision after augmentation is significant, it does not exceed the reported distal failure rate for ventriculoperitoneal shunts in children without a history of urological surgery.

Child↗

Symptomatic ureteropelvic junction obstruction in children in the era of prenatal sonography-is there a higher incidence of crossing vessels?

OBJECTIVES: To determine whether prenatal sonography and early detection and correction of ureteropelvic junction obstruction (UPJO) has changed the incidence of crossing vessels as the etiology of obstruction in older children presenting with symptomatic UPJO. METHODS: We reviewed the medical records of all children and adolescents who underwent pyeloplasty for symptomatic UPJO between 1986 and 1999, during the era of widespread use of prenatal sonography. Operative notes were used to determine which patients had obstruction due to lower pole crossing vessels. RESULTS: Thirty-eight patients were identified who underwent pyeloplasty for symptomatic UPJO. Lower pole vessels were identified in 22 (58%) of 38 patients (P <0.0001 compared with historical controls). All patients underwent dismembered pyeloplasty and remained asymptomatic after surgery, with renal scans demonstrating excellent drainage and preservation of function. CONCLUSIONS: Prenatal ultrasonography has increased the incidence of crossing vessels as the etiology of UPJO in young children and adolescents presenting with symptomatic UPJO compared with the historical incidence of 11% to 15%. This finding may impact treatment recommendations with respect to endourologic management of the obstruction in this patient population. Currently, we recommend open dismembered pyeloplasty for young children and adolescents presenting with symptomatic UPJO.

Child↗

Ureterocele prolapse-rare presentation in an adolescent girl.

Ureterocele prolapse is a rare presentation of single system ureteroceles and is usually found early in childhood. We present a rare case of recurrent prolapse of a single system ureterocele that did not present until the patient was 17 years of age.

Adolescent↗

Multi-institutional experience with the gastrointestinal composite reservoir.

PURPOSE: We evaluated multi-institutional experience with the gastrointestinal composite reservoir in patients with metabolic acidosis, the short bowel syndrome, severe pelvic radiation and/or renal insufficiency. MATERIALS AND METHODS: At 4 institutions 33 patients underwent construction of a gastrointestinal composite reservoir, including 19 with the short bowel syndrome, 13 with metabolic acidosis and 7 who also had renal insufficiency. A total of 16 patients underwent conversion of a previous diversion and the remaining 17 received new urinary diversion. Charts were reviewed for the metabolic impact of the gastrointestinal reservoir as well as any long-term sequelae. RESULTS: At a mean followup of 54 months there was a significant (p < or =0.05) improvement in mean preoperative and postoperative serum chloride (106 versus 102 mEq./l.), serum bicarbonate (23.3 versus 25 mEq./l.) and serum pH (7.36 versus 7.4). Mean serum creatinine did not significantly differ during followup in patients with normal renal function or renal insufficiency. Complications were not different than those of standard intestinal or gastric reservoirs. CONCLUSIONS: The gastrointestinal reservoir has provided an excellent metabolic balance in a large series of compromised patients with few side effects. We believe that the gastrointestinal composite reservoir represents the urinary diversion of choice when standard intestinal urinary reservoirs cannot be created in the setting of metabolic acidosis, the short bowel syndrome and severe pelvic radiation. However, the value of the gastrointestinal composite in the setting of renal insufficiency remains undetermined.

Acidosis↗

p38 MAPK mediates renal tubular cell TNF-alpha production and TNF-alpha-dependent apoptosis during simulated ischemia.

Ischemia causes renal tubular cell loss through apoptosis; however, the mechanisms of this process remain unclear. Using the renal tubular epithelial cell line LLC-PK(1), we developed a model of simulated ischemia (SI) to investigate the role of p38 MAPK (mitogen-activated protein kinase) in renal cell tumor necrosis factor-alpha (TNF-alpha) mRNA production, protein bioactivity, and apoptosis. Results demonstrate that 60 min of SI induced maximal TNF-alpha mRNA production and bioactivity. Furthermore, 60 min of ischemia induced renal tubular cell apoptosis at all substrate replacement time points examined, with peak apoptotic cell death occurring after either 24 or 48 h. p38 MAPK inhibition abolished TNF-alpha mRNA production and TNF-alpha bioactivity, and both p38 MAPK inhibition and TNF-alpha neutralization (anti-porcine TNF-alpha antibody) prevented apoptosis after 60 min of SI. These results constitute the initial demonstration that 1) renal tubular cells produce TNF-alpha mRNA and biologically active TNF-alpha and undergo apoptosis in response to SI, and 2) p38 MAPK mediates renal tubular cell TNF-alpha production and TNF-alpha-dependent apoptosis after SI.

Animals↗

Tap water and the Malone antegrade continence enema: a safe combination?

PURPOSE: The Malone antegrade continence enema provides independence and improved quality of life in patients with fecal incontinence or intractable constipation. However, isolated reports of fatal hypernatremia after irrigation with normal saline have raised safety concerns about frequent colonic irrigation in children. Significant electrolyte abnormalities have also been reported with hypertonic phosphate and high colonic tap water enemas. Because our patients routinely use tap water for Malone antegrade continence enema irrigations, we examined the safety profile of this practice MATERIALS AND METHODS: In the last 3.5 years 71 patients at our institution have used antegrade tap water enemas for managing fecal incontinence or intractable constipation. Standard serum electrolytes were measured RESULTS: We obtained 101 sets of serum electrolyte measurements in 71 patients at a mean of 8.4 months postoperatively (range 1 to 33). A girl who presented with severe hyponatremia and hypochloremia had not used the Malone antegrade continence enema for several days. The most interesting finding was significantly elevated sodium and chloride in 1 case 6 weeks after surgery that was associated with tap water treated with a home softening system. Electrolytes reverted to normal 1 week after using untreated tap water CONCLUSIONS: We did not detect significant hyponatremia or hypochloremia in any patient using tap water for Malone antegrade continence enema irrigation. Although dangerous electrolyte abnormalities are rare, potential morbidity in those cases warrants periodic evaluation. Due to the elevated sodium content in softened tap water families should be alerted to use untreated tap water for preparing enemas.

Adolescent↗

Abdominal wall hernia: an uncommon complication of in utero vesicoamniotic shunt placement.

Three cases are reported in which placement of a vesicoamniotic shunt in utero for the treatment of obstructive uropathy led to the rare complication of abdominal wall hernia. All 3 patients underwent vesicoamniotic shunt placement for severe oligohydramnios and a markedly dilated bladder in an effort to preserve renal function and to prevent pulmonary hypoplasia. All three shunts were initially placed at or above the umbilicus. The abdominal wall hernias were closed postnatally at the time of temporary vesicostomy for urethral obstruction. All 3 patients had sufficient pulmonary development, but 2 of 3 had renal failure, requiring dialysis. Management and potential etiology of this rare complication are discussed.

Amnion↗

Nephrostomy tube drainage with pyeloplasty: is it necessarily a bad choice?

PURPOSE: Despite continued controversy regarding the optimal method of urinary diversion after dismembered pyeloplasty in children, we have treated the majority of our patients with postoperative nephrostomy tubes and no stents. We report our experience. MATERIALS AND METHODS: The records of all patients who underwent surgery for ureteropelvic junction obstruction from August 1985 to October 1998 and were treated only with a nephrostomy tube after pyeloplasty were reviewed for hospital course, complications and postoperative followup. All patients had a perinephric Penrose drain as well as a Foley catheter placed for bladder drainage. RESULTS: A total of 137 pyeloplasties were performed in 132 patients, including 5 with bilateral ureteropelvic junction obstruction, using only nephrostomy tube drainage with an average followup of 2.1 years. Initial nephrostograms demonstrated good drainage across the repair with no extravasation in 91% of patients. Subsequent nephrostograms revealed a widely patent anastomosis in the remaining cases. No patient had postoperative obstruction, or required secondary pyeloplasty or nephrectomy. Urinary tract infection developed in 2 patients (1.5%). Mean hospitalization was 4.4 days. There was a significant difference in length of stay in the last 5 years compared to that in previous years (3.4 versus 5.8 days, p <0.05) and hospital stay continues to decrease. CONCLUSIONS: Use of only a nephrostomy tube after pyeloplasty resulted in few complications and an open anastomosis in 100% of cases. Nephrostomy drainage not only serves as a protective mechanism, but also allows easy access for radiographic studies before removal of the tube. In addition, nephrostomy tube drainage does not prolong hospitalization and the tube may be easily removed on an outpatient basis without further anesthesia.

Child↗