Effects of sacral neuromodulation on isolated urinary bladder function in a rat model of spinal cord injury

Third-Line Therapeutic Interventions for Non-Neurogenic Bladder Dysfunction in Children

PURPOSE OF REVIEW

The aim of this article is to review considerations and efficacy of third-line treatments for pediatric non-neurogenic bladder dysfunction, including Botulinum toxin A (BoTNA), Posterior Tibial Nerve Stimulation (PTNS), and Sacral Neuromodulation (SNM).

RECENT FINDINGS

Federal Drug Administration approval for use of beta-3-agonists in overactive detrusor activity in pediatric patients may provide an additional step prior to third-line therapies. New long-term data on pediatric SNM efficacy, complications, and revision rates will provide valuable information for counseling families. BoTNA offers a safe and efficacious treatment to decrease detrusor contractility and improve bladder capacity but is limited by the half-life of BoNTA agent. Percutaneous or transcutaneous PTNS offers improved voided volumes or cure in some patients but is time-intensive. SNM can be utilized in a variety of LUTD pathology with high success rate and cure but should consider cumulative anesthetic and fluoroscopic exposures for battery replacements and re-positioning for patient growth.

Management of Intractable Functional Constipation in Children by Interferential Therapy: Transabdominal or Pelvic Floor

BACKGROUND

To compare the effectiveness of pelvic floor interferential (IF) therapy with trans-abdominal IF therapy in children with intractable functional constipation.

METHODS

Information of 64 children (38 boys, 26 girls; mean age: 6.6 ± 2.2) with functional constipation who had been treated with IF therapy were considered for this retrospective study. Group A (n = 32) underwent pelvic IF electrical stimulation + pelvic floor muscle (PFM) exercises while the group B (n = 32) received transabdominal IF therapy + PFM exercises. A complete bowel habit diary, a constipation score questionnaire and a seeable pain scores had been recorded before, after the ending of treatment courses and six months later for children in both groups. Additionally, children had been assessed with a constipation-related quality of life questionnaire before and six months after treatment.

RESULTS

The number of patients who compiled the diagnostic criteria for constipation significantly decreased in both groups after treatment, in which 27/32 (84.3%) of patients in each group had no constipation after the ending of therapy courses (P = 1). Fecal soiling episodes reduced in both groups after treatment, this finding was significantly higher in group A than in group B after the ending of therapy courses (P = 0.05) and six months later (P = 0.01).

CONCLUSION

Results of this study showed that using IF therapy both pelvic floor and transabdominal significantly boosts the effects of treatment among patients with functional constipation. Pelvic floor IF therapy is more effective in patients who had concomitant fecal soiling.

Transcutaneous Neuromodulation for Constipation and Fecal Incontinence in Children: A Systematic Review and Meta-Analysis

INTRODUCTION

Constipation is a disorder with a multifactorial origin. Constipation has a varied clinical presentation, including infrequent defecation of bulky stools and episodes of retentive fecal incontinence. Neuromodulation has been used to treat many health problems, with promising results.

OBJECTIVE

To conduct a systematic review of randomized clinical trials based on the effects of transcutaneous neuromodulation in treating constipation and retentive fecal incontinence in children and adolescents.

METHODS

A systematic review of randomized clinical trials was performed. Medline (PubMed), PEDro, SciELO, Cochrane (CENTRAL), Embase, and Scopus databases were searched from March 2000 to August 2022. We included clinical trials evaluating transcutaneous neuromodulation in children with constipation and fecal incontinence compared or associated with other types of treatment. Two reviewers independently selected relevant studies, assessed the methodological quality, and extracted the data.

RESULTS

Three studies with 164 participants were included in this review. Two meta-analyses were generated based on these studies. These analyses revealed that transcutaneous neuromodulation is an effective adjuvant treatment modality that improves children's constipation and retentive fecal incontinence. The methodological quality of the included studies was classified as high based on the assessment of the quality of evidence, with a high degree of confidence based on the GRADE system.

CONCLUSIONS

Transcutaneous neuromodulation is an effective adjuvant treatment modality for children with constipation and retentive fecal incontinence.

Electric nerve stimulation for overactive bladder: an umbrella review

Numerous systematic reviews and meta-analyses have reported the effect of electrical nerve stimulation (ENS) on overactive bladder (OAB). However, these results are contradictory. We conducted an umbrella review to summarize the evidence and evaluate the effectiveness of ENS for OAB by using an umbrella review methodology from multiple perspectives with sufficient methodological quality. We searched the PubMed, EMBASE, Cochrane Library, Web of Science, CINAHL and PsycINFO databases and two Chinese databases (CNKI and CBM) to identify articles written in English or Chinese that were published up to 15 February 2021. Two authors of this review independently selected the studies, assessed their quality, and extracted the data from all the included studies. We performed a quality assessment of eligible reviews using the AMSTAR 2.0 tool and estimated the summary effect size, 95% confidence intervals, 95% prediction intervals and heterogeneity. Ten systematic reviews and meta-analyses covering 89 randomized controlled trials and 16 prospective cohort studies with a total population of 5004 participants that investigated the effect of ENS for OAB in terms of 17 different outcomes were identified. ENS seems effective and safety for OAB, with our results showing weak evidence of clinical efficacy and no evidence of side effects. To recommend ENS as a practical treatment option for OAB, however, more high-quality research is needed.

Sacral nerve stimulation with appropriate parameters improves constipation in rats by enhancing colon motility mediated via the autonomic-cholinergic mechanisms

Although sacral nerve stimulation (SNS) has been applied for treating constipation, its parameters were adopted from SNS for fecal incontinence, its effects are limited, and mechanisms are largely unknown. We investigated the effects and mechanism of SNS with appropriate parameters on constipation in rats treated with loperamide. First, using rectal compliance as an outcome measure, an experiment was performed to derive effective SNS parameters. Then, a 7-day SNS was performed in rats with constipation induced by loperamide. Autonomic functions were assessed by spectral analysis of heart rate variability (HRV) derived from an electrocardiogram. Serum levels of pancreatic polypeptide (PP), norepinephrine (NE), and acetylcholine (ACh) in colon were assessed. 1) Acute SNS at 5 Hz, 100 µs was found effective in enhancing rectal compliance and accelerating distal colon transit (P < 0.05 vs. sham SNS). 2) The 7-day SNS normalized loperamide-induced constipation, assessed by the number, weight, and water content of fecal pellets, and accelerated the distal colon transit (29.4 ± 3.7 min with sham SNS vs. 16.4 ± 5.3 min with SNS but not gastric emptying or intestinal transit. 3) SNS significantly increased vagal activity (P = 0.035) and decreased sympathetic activity (P = 0.012), assessed by spectral analysis of HRV as well as by the serum PP. 4) SNS increased ACh in the colon tissue; atropine blocked the accelerative effect of SNS on distal colon transit. We concluded that SNS with appropriate parameters improves constipation induced by loperamide by accelerating distal colon motility, mediated via the autonomic-cholinergic function.NEW & NOTEWORTHY Although sacral nerve stimulation (SNS) has been applied for treating constipation, its parameters were adopted from SNS for fecal incontinence, effects are limited, and mechanisms are largely unknown. This paper shows that SNS with appropriate parameters improves constipation induced by loperamide by accelerating distal colon motility mediated via the autonomic-cholinergic function.

Effect of Early Sacral Neuromodulation on Bladder Function in a Rat Model of Incomplete Spinal Cord Injury Due to Focal Contusion

OBJECTIVES

Incomplete spinal cord injury (SCI) accounts for two-thirds of all SCIs in clinical practice. Preclinical research on the effect of sacral neuromodulation (SNM) on bladder function, however, has been focused only on animal models of complete SCI. We aimed to evaluate the effect of early SNM on bladder responses in a rat model of incomplete SCI.

MATERIALS AND METHODS

Altogether, 21 female Sprague-Dawley rats were equally assigned to control (CTR), SCI + sham stimulation (SHAM), and SCI + SNM (SNM) groups. In the SHAM and SNM groups, incomplete SCI was created by producing a moderate contusion with an NYU-MASCIS impactor at the T9-T10 level of the spine, with needle electrodes implanted bilaterally into the S2 or S3 sacral foramen. Only SNM group underwent electrical stimulation for 28 days, beginning on day 7 after SCI. Cystometry was performed 35 days after SCI.

RESULTS

Although the interval between voiding contractions was significantly longer in the SHAM group than the CTR group (25.5 ± 1.4 vs. 12.5 ± 1.7 min; p < 0.05), there were no significant differences between the SNM group (16.5 ± 1.5 min) and the CTR group. Maximum voiding contraction pressure did not differ among the groups. The SNM group had a significantly lower frequency (3.5 ± 0.5 vs. 14.6 ± 2.0; p < 0.05) and maximum pressure (11.4 ± 6.2 vs. 21.3 ± 1.8 cmH₂ O; p < 0.05) of nonvoiding contractions than the SHAM group.

CONCLUSIONS

Our results provide experimental evidence that early SNM treatment may prevent or diminish bladder dysfunctions (e.g., detrusor overactivity, abnormal micturition reflex) in a clinical condition of incomplete SCI.

Diagnosis and management of bladder bowel dysfunction in children with urinary tract infections: a position statement from the International Children's Continence Society

BACKGROUND

We present a consensus view from the International Children's Continence Society (ICCS) on the evaluation and management of bladder bowel dysfunction (BBD) in children with urinary tract infection (UTI). The statement aims to highlight the importance of BBD in the development and recurrence of childhood UTI and its management to reduce its associated morbidity and sequelae.

METHODS

A systematic literature search was done on PubMed, Embase, and Scopus databases until August 15, 2016. Relevant publications concerning BBD and its relationship with UTI among children were reviewed and aggregated for statements of recommendation. Discussion by the ICCS Board and a multi-disciplinary core group of authors resulted in a document available on its website for all ICCS members to review. Insights and feedback were considered with consensus and agreement reached to finalize this position statement.

RESULTS

BBD in children with UTI is summarized. Details regarding epidemiology, pathophysiology, and recommendations for general and family practitioners and pediatricians relating to the evaluation and management of this condition are presented.

CONCLUSIONS

This document serves as the position statement from ICCS, based on literature review and expert opinion providing our current understanding of BBD in children with UTI.

Development of a Remote-Controlled Implantable Rat Sacral Nerve Stimulation System

OBJECTIVES

Sacral nerve stimulation (SNS) is a surgical treatment of urinary and fecal incontinence. Despite its clinical efficacy, the mechanisms of action of SNS are still poorly known. This may be related to the use of acute stimulation models. Up to date, no rodent model of chronic SNS implants has been developed. Therefore, the aim of this study was to create a fully implantable and remotely controllable stimulating device to establish an animal model of chronic SNS.

MATERIALS AND METHODS

The stimulating device consisted of an implantable pulse generator linked to a platinum electrode. The communication with the device was made through an inductive link which allowed to adjust the stimulation parameters; that is, to turn the device on and off or check the battery status remotely. Rats underwent two surgical procedures. In the first procedure, we achieved chronic sacral stimulation but the implanted electrode was not fixated. In the second procedure, the electrode was fixated in the sacral foramen using dental resin. In both cases, the correct positioning of the electrode was evaluated by computed tomography (CT) imaging and the presence of tail tremor in response to high intensity stimulation. We only tested the function of implanted electrode with fixation using micturition frequency assessment following bipolar or unipolar SNS for three days after recovery.

RESULTS

CT imaging showed that implantation of the electrode required fixation as we found that the second surgical procedure yielded a more precise placement of the implanted electrode. The correct placement of implanted electrode observed with imaging was always correlated with a successful tail tremor response in rats, therefore we pursued our next experiments with the second surgical procedure and only assessed the tail tremor response. We found that both bipolar and unipolar SNS reduced micturition frequency.

CONCLUSION

This stimulating device provides an efficient method to perform chronic SNS studies in rats.

Protocol for a randomized clinical trial investigating early sacral nerve stimulation as an adjunct to standard neurogenic bladder management following acute spinal cord injury

Background

Neurogenic bladder (NGB) dysfunction after spinal cord injury (SCI) is generally irreversible. Preliminary animal and human studies have suggested that initiation of sacral neuromodulation (SNM) immediately following SCI can prevent neurogenic detrusor overactivity and preserve bladder capacity and compliance. We designed a multicenter randomized clinical trial to evaluate the effectiveness of early SNM after acute SCI.

Methods/Design

The scientific protocol comprises a multi-site, randomized, non-blinded clinical trial. Sixty acute, acquired SCI patients (30 per arm) will be randomized within 12 weeks of injury. All participants will receive standard care for NGB including anticholinergic medications and usual bladder management strategies. Those randomized to intervention will undergo surgical implantation of the Medtronic PrimeAdvanced Surescan 97,702 Neurostimulator with bilateral tined leads along the S3 nerve root in a single-stage procedure. All patients will undergo fluoroscopic urodynamic testing at study enrollment, 3 months, and 1-year post randomization. The primary outcome will be changes in urodynamic maximum cystometric capacity at 1-year. After accounting for a 15% loss to follow-up, we expect 25 evaluable patients per arm (50 total), which will allow detection of a 38% treatment effect. This corresponds to an 84 mL difference in bladder capacity (80% power at a 5% significance level). Additional parameters will be assessed every 3 months with validated SCI-Quality of Life questionnaires and 3-day voiding diaries with pad-weight testing. Quantified secondary outcomes include: patient reported QoL, number of daily catheterizations, incontinence episodes, average catheterization volume, detrusor compliance, presence of urodynamic detrusor overactivity and important clinical outcomes including: hospitalizations, number of symptomatic urinary tract infections, need for further interventions, and bowel and erectile function.

Discussion

This research protocol is multi-centered, drawing participants from large referral centers for SCI and has the potential to increase options for bladder management after SCI and add to our knowledge about neuroplasticity in the acute SCI patient.

Trial registration

ClinicalTrials.gov #NCT03083366 1/27/2017.

Neurostimulation Therapy for Non-neurogenic Overactive Bladder in Children: A Meta-analysis

OBJECTIVE

To assess the efficacy and safety of neurostimulation for non-neurogenic overactive bladder in children, we conducted a meta-analysis of randomized controlled trials (RCTs).

MATERIALS AND METHODS

A systematic literature search was performed on August 2016. RCTs were evaluated according to the Cochrane Collaboration risk of bias assessment. Number of patients with post-treatment partial response (PR) (50%-89%), complete response (CR) (≥90%), and full response (FR) (100%) were extracted for relative risk (RR) and 95% confidence interval (CI). Effect estimates were pooled using the Mantel-Haenszel method with random effect model if significant inter-study heterogeneity (P <.1) was noted. Subgroup analysis was performed according to each treatment setting (PROSPERO CRD42016043502).

RESULTS

Five eligible studies (245 patients) were included. Overall effect estimates showed that compared with standard urotherapy, neurostimulation demonstrated significantly better ≥50% (PR + CR + FR) response (RR = 2.8, 95% CI 1.1-7.2), but not ≥90% (CR + FR) response (RR = 8.28, 95% CI 0.65-105.92). Clinic-based neurostimulation had significantly better treatment outcomes for both ≥50% (PR + CR + FR) and ≥90% (CR + FR) responses (RR = 3.24, 95% CI 1.89-5.57; RR = 20.81, 95% CI 2.97-145.59, respectively), whereas a self-administered regimen showed no differences for both ≥50% (PR + CR + FR) and ≥90% (CR + FR) response rates between treatment groups (RR = 2.61, 95% CI 0.48-14.15; RR = 3.55, 95% CI 0.19-67.82, respectively). No serious adverse events were reported.

CONCLUSION

Neurostimulation therapy may lead to better partial improvement of non-neurogenic overactive bladder; however, it may not render a definitive complete response. Office-based neurostimulation seems more efficacious than self-administered neurostimulation. Further RCTs are needed to compare outcomes of the 2 regimens.

Electroneurostimulation for the management of bladder bowel dysfunction in childhood

Both non-invasive and invasive electroneurostimulation (ENS) modalities for bladder bowel dysfunction have been studied and reported in children. A summary of the proposed mechanism of actions and the more commonly used and recently reported techniques and outcomes are described. This includes transcutaneous electrical nerve stimulation, functional electrical nerve stimulation, intravesical electrical nerve stimulation, percutaneous tibial nerve stimulation and sacral neuromodulation in conditions including overactive bladder, enuresis, dysfunctional voiding, constipation, combined bladder bowel dysfunction and neuropathic bladder and bowel dysfunction. There is a need for further high quality randomised trials as well as long-term outcomes to establish whether ENS is able to alter the long-term trajectory for an individual child with bladder bowel dysfunction.