Is Statistical Significance Sufficient? Importance of Interaction and Confounding in Hypospadias Analysis

Dorsal penile block versus caudal epidural anesthesia effect on complications post-hypospadias repair: Dilemmas, damned dilemmas and statistics

The evidence examining the effects of regional blocks on complications posthypospadias repair has been controversial. Nine observational studies have been published thus far, with inconsistent and somewhat contradictory results. In this educational article, we attempt to explain the concepts of study accuracy and precision in the context of the hypospadias literature to shed some light on the reasons behind those controversies. Methodological issues such as selection bias, confounding effect, sample size, confidence interval and study generalizability from studies involving dorsal penile block versus caudal epidural anesthesia in hypospadias repair are discussed.

Incontinence affects health-related quality of life in children and adolescents with spina bifida

PURPOSE

Despite devoting many resources to managing urinary and fecal incontinence (UI and FI) in children with spina bifida (SB), it remains unclear whether either is associated with lower health-related quality of life (HRQOL). We sought to determine the impact of UI and FI on HRQOL in this population.

MATERIALS AND METHODS

Children with SB (8-17 years) living in the United States were surveyed online and in SB clinics (2013-15). We evaluated incontinence over the previous 4 weeks using a UI dry interval (<4 h, ≥4 h), FI clean interval (<1 week, ≥ 1 week), and self-reported amount of UI and FI (for each: a lot, medium, a little, none). HRQOL was assessed with QUALAS, a validated SB-specific instrument. Linear regression was used.

RESULTS

The mean age of 298 children was 12.5 years (52.0% male). Overall, 73.1% had UI, 52.3% had FI, and 43.6% had both. Adjusting for concurrent UI and FI, any UI was associated with lower HRQOL in 14-17 year olds (p < 0.0001) and 10-13 year olds (p = 0.048), but not 8-9 year olds (p = 0.98) (Figure). All age groups reported lower HRQOL with FI (p ≤ 0.0001). On multivariate analysis, UI and FI incontinence intervals were not associated with lower HRQOL for any age group (p ≥ 0.58 and p ≥ 0.10, respectively). Higher quantities of UI were associated with ever-lower HRQOL, particularly in 14-17 year olds (p ≤ 0.02). Any quantity of FI was associated with lower HRQOL in all ages. The findings did not change significantly on exploratory analysis correcting for demographic and clinical variables.

DISCUSSION

We report the first evidence that incontinence matters to children and adolescents with SB. Being a cross-sectional study, we were unable to track HRQOL over time. A prospective study is required to assess if HRQOL impact of UI indeed changes as a child grows up and if improving incontinence with treatments improves HRQOL. Findings are similar to those reported in adults with SB and suggest that the concept of "social continence" based on time interval has no HRQOL relevance in children, adolescents or adults with SB.

CONCLUSIONS

UI is negatively associated with HRQOL in children with SB in an age-dependent fashion: starting in 10 year olds and increasing until 14 years. FI correlates with lower HRQOL regardless of age. Similar to findings in adults with SB, HRQOL is lower with increasing amounts of UI and not the length of a dry interval. FI impacts HRQOL uniformly, regardless of frequency or amount.

Application of the STROBE statement to the hypospadias literature: Report of the international pediatric urology task force on hypospadias

INTRODUCTION

Observational studies, particularly case series, represent the majority of the current hypospadias research. As a result, this literature lacks standardization of surgical techniques, uniform definitions of hypospadias complications, and consistency of outcome reporting, which may make it difficult to compare results across studies. A modified version of the STROBE statement, containing 20 items, was presented at the International Pediatric Urology Task Force on Hypospadias meeting to assist with clear and transparent reporting of hypospadias studies. The adoption and implementation of this modified tool will allow investigators and health care providers to critically evaluate quality and identify bias within the literature. In addition this instrument will ensure consistency of reporting, improving objective comparisons between studies, unification of results, and development of evidence-based clinical guidelines.

METHODS

In this article, we have applied the modified STROBE statement to the hypospadias literature, aiming to create a guide on study reporting for pediatric urologists, and ultimately improve the quality of research in our field. We present itemized recommendations for adequate reporting of hypospadias studies and case series, ranging from drafting the abstract to addressing biases and potential sources of confounding. Included with each item is a brief explanation of its importance and potential effect on the study, as well as pertinent examples of hypospadias articles.

RESULTS

A modified STROBE summary table containing 20 items is presented in (Supplementary Table 1).

CONCLUSIONS

If properly conducted and reported, hypospadias studies have the potential to provide useful information to clinicians and surgeons. However, authors should recognize the inherent limitations of these observational studies, especially in the form of bias, which may introduce invalid data or limit generalizability. Thus, we expect that the use of this guiding tool will not only improve transparency of hypospadias reporting, but also improve its methodological quality, allowing proper comparison and interpretation of data across different institutions.

Cause and Effect versus Confounding-Is There a True Association between Caudal Blocks and Tubularized Incised Plate Repair Complications?

PURPOSE

We studied the impact of caudal block vs dorsal penile block on the rate of urethrocutaneous fistula and glans dehiscence in children who underwent hypospadias repair.

MATERIALS AND METHODS

We retrospectively reviewed the records of 849 consecutive patients who underwent tubularized incised plate repair between 2004 and 2015. A total of 331 cases with incomplete medical records, other techniques and redo repair were excluded. The preference for caudal block was based on anesthesiologist discretion. Age at surgery, meatal location, preoperative testosterone stimulation, type of regional anesthesia (caudal block vs dorsal penile block), degree of ventral curvature, surgeon expertise and complications (urethrocutaneous fistula/glans dehiscence) were captured. Univariate and multivariable analyses were done of risk factors for complications.

RESULTS

Median age at surgery was 18 months and median followup was 6 months. Of 518 patients 405 (78%) had distal and 113 (22%) had mid shaft/proximal defects. Complications developed in 37 cases (7%), including urethrocutaneous fistula in 21 (19 with a caudal block and 2 with a dorsal penile block) and glans dehiscence in 16 (13 with a caudal block and 3 with a dorsal penile block). On univariate analysis preoperative testosterone stimulation vs no preoperative testosterone stimulation (13.0% vs 6.2% of cases, p = 0.04), mid shaft/proximal vs distal defects (15.9% vs 4.7%, p <0.01) and caudal block (8.7% vs 3.3%, p = 0.03) were significantly associated with more complications. However, on multivariable analysis the associations of preoperative testosterone stimulation (OR 1.2, 95% CI 0.4-3.7) and caudal block (OR 2.4, 95% CI 0.9-6.4) with complications did not hold. Only the combination of meatal location/ventral curvature remained as an independent risk factor for urethrocutaneous fistula/glans dehiscence (OR 2.4, 95% CI 1.1-5.7, p = 0.04).

CONCLUSIONS

Our data indicate that hypospadias severity and not the type of regional anesthesia was the only risk factor significantly associated with postoperative complications. To confirm these findings and provide strong and definitive evidence on this topic a well powered, randomized, controlled trial is clearly required.

Failed hypospadias repair: An algorithm for secondary reconstruction using remaining local tissue

Salvage hypospadias surgery is performed after failed primary reconstruction. Several treatment strategies have been suggested, all with pros and cons. The aim of this study was to evaluate our treatment algorithm for primary hypospadias repair applied to secondary cases in which a salvage procedure is indicated and, most importantly, local tissue is present. The algorithm was applied to 36 consecutive patients who had undergone a total of 109 surgical procedures before referral. In accordance with the algorithm, 12 patients without ventral curvature achieved a satisfactory result with one procedure by the use of local skin flaps. Six patients with moderate ventral curvature underwent orthoplasty, fistula closure, and/or urethral reconstruction using local skin flaps in one session. Eighteen patients with a severe ventral curvature or a proximal meatus were reconstructed in two stages using Byars' technique. After a median of two salvage procedures (range: 1-4), all patients but one, who awaits splitting of a skin bridge in the meatus, were successfully reconstructed. Two patients in active follow-up have potential problems requiring further surgery. Our findings indicate that failed hypospadias repairs are often due to an underestimation of the ventral curvature at the initial repair. Therefore, reevaluation of the degree of curvature is important. One-stage salvage repairs can be used, provided that none or minimal curvature remains. In cases of marked curvature, however, a meticulous resection of the chordee and ventral scarring is crucial. The subsequent repair of the large ventral defect and the long urethral reconstruction can, in most cases, be safely managed in a two-stage procedure.

Failed hypospadias in paediatric patients

Failed hypospadias refers to any hypospadias repair that leads to complications or causes patient dissatisfaction. The complication rate after hypospadias repairs ranges from 5-70%, but the actual incidence of failed hypospadias is unknown as complications can become apparent many years after surgery and series with lifelong follow-up data do not exist. Moreover, little is known about uncomplicated repairs that fail in terms of patient satisfaction. Risk factors for complications include factors related to the hypospadias (severity of the condition and characteristics of the urethral plate), the patient (age at surgery, endocrine environment, and wound healing impairment), the surgeon (technique selection and surgeon expertise), and the procedure (technical details and postoperative management). The most important factors for preventing complications are surgeon expertise (number of cases treated per year), interposition of a barrier layer between the urethroplasty and the skin, and postoperative urinary drainage. Major complications associated with failed hypospadias include residual curvature, healing complications (preputial dehiscence, glans dehiscence, fistula formation, and urethral breakdown), urethral obstruction (meatal stenosis, urethral stricture, and functional obstruction), urethral diverticula, hairy urethra, and penile skin deficiency.

Coverage of urethroplasty in pediatric hypospadias: randomized comparison between different flaps

OBJECTIVES

The use of covering urethroplasty with flaps in hypospadias surgery has been well recommended. Various techniques have been described for flap harvesting. The aim of the present study was to compare the outcome and complication rate of dorsal preputial flaps and ventral dartos flaps.

METHODS

A total of 130 patients were prospectively evaluated from January 2008 to December 2011. Using the tubularized incised plate urethroplasty procedure, urethroplasty was carried out by a single surgeon. Patients were randomly divided in two groups: group A (57 patients), in which a preputial flap was carried out using three different techniques; and group B (73 patients), in which a single or a double ventral dartos flap was used.

RESULTS

A total of 41 complications occurred in 24 patients. Urethrocutaneous fistulas were observed in 14.9%, quite equally distributed between groups A and B. There was only one urethrocutaneous fistula in a patient treated with the double ventral dartos flaps. Five cases (3.8%) of glans dehiscence were observed: four after single ventral dartos flap and one after dorsal preputial flap. Six patients in group A and seven in group B experienced meatal stenosis. In three cases of iatrogenic torsion of the penis, a dorsal preputial flap was laterally transposed. Finally, a lower complication rate was observed for double ventral dartos flap versus the other techniques.

CONCLUSIONS

The use of a double ventral dartos flap should represent the first-line technique for coverage of distal urethroplasty.