Incidence of new onset metabolic acidosis following enteroplasty for myelomeningocele.

PURPOSE: Extant literature is mixed regarding risk of metabolic acidosis after enteroplasty for myelomeningocele. This study is the first known attempt to describe the pattern of developing metabolic acidosis in a group of children who underwent enteroplasty and served as their own controls. Multiple preoperative and postoperative laboratory measures for each child were obtained for comparison. MATERIALS AND METHODS: This retrospective cohort study allowed participants to serve as their own controls for pre-intervention and post-intervention analysis. The setting was a tertiary, university affiliated, interdisciplinary spina bifida program. All patients followed in the spina bifida program who had undergone ileal or colonic enteroplasty were included for review (total 113). Strict exclusion criteria were preoperatively diagnosed renal insufficiency, preexisting metabolic acidosis consistent with renal tubular acidosis (pH less than 7.35, bicarbonate 20 mmol/l or less) and history of augmentation using gastric or ureteral tissue. Final analysis included 71 children who met inclusion criteria. Children in our spina bifida program periodically undergo routine laboratory evaluation of electrolytes, blood urea nitrogen, creatinine, blood count, and venous blood gases including pH, bicarbonate and partial pressure of carbon dioxide. Primary outcome measures were comparative shifts in blood gases and electrolytes that would confirm the new onset of metabolic acidosis after enteroplasty. Changes in electrolytes and serum creatinine were secondary outcome measures to identify potential markers for postoperative effects. With each child as his/her own control, analysis included paired t tests. RESULTS: No statistically significant differences (p <0.05) were found when comparing laboratory values before and after bladder augmentation, including pH, bicarbonate, partial pressure of carbon dioxide and electrolytes. No child had metabolic acidosis based on the aforementioned criteria. Followup ranged from 1 to 138 months after enteroplasty (mean 46.8). Respiratory compensation was considered in the analysis, and no difference in partial pressure of carbon dioxide following surgery was noted (p = 0.65). CONCLUSIONS: To our knowledge no previous study has examined the matched paired results of before and after development of metabolic acidosis among children (serving as their own controls) with myelomeningocele undergoing ileal or colonic enteroplasty. The negative statistical results in this controlled cohort are clinically significant. If a child with myelomeningocele has metabolic acidosis after enteroplasty, other clinical reasons beyond the effects of surgery warrant careful consideration.

Usefulness of short-term retrievable ureteral stent in pediatric laparoscopic pyeloplasty.

PURPOSE: Methods of stenting after laparoscopic pyeloplasty have included indwelling Double-J stents and percutaneous nephrostomy tubes. The disadvantages of these methods are that they necessitate a second surgery for stent removal or require an external drainage bag. To circumvent these issues, the tolerance, safety and outcomes of using a Double-J ureteral stent with a dangler, permitting early office removal, was investigated in a series of pediatric laparoscopic pyeloplasties. MATERIALS AND METHODS: Medical records from a consecutive series of pediatric patients undergoing transperitoneal laparoscopic pyeloplasties were reviewed. Indications for surgery included ipsilateral flank pain with severe hydronephrosis (12 patients), recurrent pyelonephritis with severe hydronephrosis (2), and hematuria and flank pain (6). All patients were discharged home within 24 to 48 hours of the procedure with prophylactic oral antibiotics. The stent was removed by postoperative day 18 during a followup office visit. Patient tolerance of the indwelling stent, outpatient removal and success of pyeloplasty were assessed. RESULTS: A total of 20 patients underwent transperitoneal laparoscopic pyeloplasty by 1 surgeon (LAB) between 2001 and 2005. All patients underwent cystoscopy and retrograde Double-J ureteral stent placement before pyeloplasty under the same anesthesia. Mean patient age at operation was 11.3 years (median 11.3, range 4.6 to 17.2). Stents were left indwelling for a mean of 10.3 days (median 10, range 7 to 18). All patients tolerated the Double-J stent well, with 2 requiring anticholinergic therapy for mild urgency symptoms and 1 demonstrating urinary tract infection. All patients tolerated outpatient stent removal via the dangler at the office without discomfort. One patient was lost to followup. At a mean followup of 1.04 years (range 0.1 to 2.88) 17 of 19 patients (89%) had resolution of flank pain/urinary tract infections, with sonographic improvement in hydronephrosis with or without endoscopic intervention. Six patients (30%) had flank pain with or without continuous hydronephrosis and required re-stenting, and 3 also required balloon dilation. Of these 6 patients 2 (10%) had recurrent ureteropelvic junction obstruction and required open pyeloplasty. All patients are now clinically and radiologically unobstructed and asymptomatic. CONCLUSIONS: Pediatric transperitoneal laparoscopic pyeloplasty with indwelling Double-J ureteral stent with a dangler is successful and the stent is well tolerated. Whether the duration of ureteral stenting affects the surgical success will require further controlled long-term studies.

Laparoscopic decision making: impact of preoperative reading and laparoscopic experience.

PURPOSE: A competent laparoscopic surgeon requires good technical skills and good surgical judgment. The assessment of technical skills using bench models and simulators has been well studied. However, there has been a paucity of studies examining the cognitive aspects of surgery. We developed a novel tool to assess the procedural knowledge and higher level decision making required for successful laparoscopic nephrectomy. We assessed the effect of laparoscopic experience and the effect of self-preparation or preoperative reading on surgical decision making abilities using a novel assessment tool and methodology. MATERIALS AND METHODS: A total of 17 novice and advanced urology residents were randomized to preoperative reading or no preoperative reading. Subjects viewed laparoscopic nephrectomy clips and verbalized their thought processes. Their performance was transcribed and blindly rated using a new surgical decision making rating scale. RESULTS: The correlation with overall surgical decision making rating scale score was good for years of training and moderate for the number of laparoscopic cases performed (r = 0.7 and 0.54, respectively, p < 0.05). Preoperative reading did not have a significant impact on the overall surgical decision making rating scale score (p > 0.05). However, when stratified by laparoscopic experience level (fewer than 10 cases), preoperative reading had a significant impact on the performance of novices with respect to the knowledge components of the procedure but not the judgment domain (each p > 0.05). CONCLUSIONS: Overall preoperative reading did not improve the surgical decision making rating scale. Novice procedural knowledge benefited from preoperative reading but not surgical judgment. The surgical decision making rating scale appears promising and it may have future implications for assessing surgical competency.

Autologous buccal mucosa vulvovaginoplasty for high urogenital sinus.

Feminizing genitoplasty for mid to high urogenital sinus confluence is challenging surgery, especially in the postpubertal patient. We report a surgical alternative for a complex postpubertal case with scarce perineal tissue. An autologous buccal mucosa vulvovaginoplasty was performed in a postpubertal patient with adrenogenital syndrome, permitting vaginal lengthening, creation of labia minora and minimal urethral dissection. This surgical approach avoided female hypospadias, as seen with the total urogenital sinus mobilization repair, and the risks of extensive urethral dissection, seen with the vaginal pull-through procedure, but yet solved the dilemma of mucosal coverage for the vulva and anterior vaginal wall. Buccal mucosa is a natural replacement for the female vulvar and vaginal glabrous skin, and is an excellent adjunct or alternative in challenging reconstructions.

Cost analysis of laparoscopic versus open orchiopexy in the management of unilateral nonpalpable testicles.

PURPOSE: Laparoscopic exploration for the nonpalpable testicle (NPT) has been criticized for increased costs compared with primary inguinal/scrotal exploration, mostly due to high equipment costs and the need for open inguinal/scrotal exploration in many cases. We assessed costs associated with diagnostic laparoscopy vs inguinal/scrotal exploration followed by selective open or laparoscopic treatment for unilateral NPT to identify the most important factors that influence cost. MATERIALS AND METHODS: A comprehensive literature review determined the probabilities of intra-abdominal or inguinal nubbins, blind-ending vas/vessels and intra-abdominal or inguinal gonads in patients with unilateral NPT. The costs of anesthesia, equipment and operating room use were obtained from our institution or derived from the literature. A model was created using computer software to compare the costs of initial scrotal/inguinal approach or initial laparoscopic exploration in a theoretical population of boys with unilateral NPT. We established a set of assumptions and generated a series of 1-way sensitivity analyses to detect cost influencing parameters. RESULTS: Based on the probabilities of intraoperative anatomical gonadal findings, use of reusable laparoscopic equipment and encompassing the ultimate surgical procedure needed initial laparoscopic evaluation was less costly than initial scrotal/inguinal exploration by 69 US dollars on a population basis. One-way sensitivity analyses showed that initial laparoscopic exploration was less costly if the operative time of laparoscopic exploration did not exceed 19 minutes and the cost of disposable laparoscopic equipment was less than 147 US dollars. CONCLUSIONS: On a population basis initial laparoscopic evaluation of the clinically nonpalpable testicle has a cost saving advantage (69 US dollars) over initial inguinal-scrotal exploration when reusable laparoscopic equipment is primarily used, disposable equipment costs are kept low (147 US dollars or less) and operating room time for diagnostic laparoscopy are at national standards (19 minutes or less). These findings hold true for a wide range of probabilities and duration of inguinal exploration time. Given that all of these caveats are easily achievable, cost should not be used as a factor to bias against initial laparoscopic exploration.