Surgery for constipation: systematic review and clinical guidance: Paper 1: Introduction & Methods

AIM

This manuscript provides the introduction and detailed methodology used in subsequent reviews to assess the outcomes of surgical interventions with the primary intent of treating chronic constipation in adults and to develop recommendations for practice.

METHOD

PRISMA guidance was adhered to throughout. A literature search was performed in public databases between January 1960 and February 2016. Studies that fulfilled strictly-defined PICOS (patients, interventions, controls, outcome, and study design) criteria were included. The process involved two groups of participants: (i): 'a clinical guidance group' of 18 UK experts (including junior support) who performed the systematic reviews and produced summary evidence statements (SES) based strictly on data synthesis in each review. The same group then produced prototype graded practice recommendations (GPRs) based on coalescence of SES and expert opinion; (ii): a European Consensus group of 18 ESCP (European Society of Coloproctology) nominated experts from nine European countries evaluated the appropriateness of each prototype GPR based on published RAND/UCLA methodology.

RESULTS

An overview of the search results is provided in this manuscript. A total of 156 studies from 307 full text articles (from 2551 initially screened records) were included, providing data on procedures characterized by: (i) colonic resection (n = 40); (ii) rectal suspension (n = 18); (iii) rectal wall excision (n = 44); (iv) rectovaginal septum reinforcement (n = 47); (v) sacral nerve stimulation (n = 7). The overall quality of evidence was poor with 113/156 (72.4%) studies providing only Oxford level IV evidence. The best evidence was extracted for rectal excisional procedures, where the majority of studies were Oxford level I or II. The five subsequent reviews provide a total of 99 SES (reflecting perioperative variables, efficacy, harms and prognostic variables) that contributed to 100 prototype GPRs covering patient selection, procedural considerations and patient counselling. The final manuscript details the 85/100 GPRs that were deemed appropriate by European Consensus (remaining 15 were all uncertain) and future research recommendations.

CONCLUSION

This manuscript and the following 6 papers suggest that the evidence base for surgical management of chronic constipation is currently poor although some expert consensus exists on best practice. Further studies are required to inform future commissioning of treatments and of research funding.

Surgery for constipation: systematic review and practice recommendations: Results IV: Recto-vaginal reinforcement procedures

AIM

To assess the outcomes of recto-vaginal reinforcement procedures in adults with chronic constipation.

METHOD

Standardised methods and reporting of benefits and harms were used for all CapaCiTY reviews that closely adhered to PRISMA 2016 guidance. Main conclusions were presented as summary evidence statements with a summative Oxford Centre for Evidence-Based Medicine (2009) level.

RESULTS

Forty-three articles were identified, providing data on outcomes in 3346 patients. Average length of procedures ranged between 20 and 169 min, and length of stay between 1 and 15 days. Complications typically occurred after 7-17% of procedures (range 0-61%). Post-operative bleeding was uncommon (0-4%) as well as haematoma or sepsis (0-2%). Fistulation did not occur in most studies. Two procedure-related deaths were observed for 3209 patients. Although inconsistent, 78% of patients reported a satisfactory or good outcome, with 30-50% experiencing reduced symptoms of straining, incomplete emptying or reduced vaginal digitation. About 17% of patients developed anatomical recurrence. Considering measures of harm and global satisfaction rating scales, there was insufficient evidence to prefer one type of procedure over another. There was no evidence to support better outcomes based on selection of patients with a particular size or grade of rectocoele.

CONCLUSION

Evidence supporting recto-vaginal reinforcement procedures is currently derived from observational studies and comparisons, with only one high quality study. Large trials are needed to inform future clinical decision making.

Surgery for constipation: systematic review and practice recommendations: Graded practice and future research recommendations

AIM

This manuscript forms the final of seven that address the surgical management of chronic constipation (CC) in adults. The content coalesces results from the five systematic reviews that precede it and of the European Consensus process to derive graded practice recommendations (GPR).

METHODS

Summary of review data, development of GPR and future research recommendations as outlined in detail in the 'introduction and methods' paper.

RESULTS

The overall quality of data in the five reviews was poor with 113/156(72.4%) of included studies providing only level IV evidence and only four included level I RCTs. Coalescence of data from the five procedural classes revealed that few firm conclusions could be drawn regarding procedural choice or patient selection: no single procedure dominated in addressing dynamic structural abnormalities of the anorectum and pelvic floor with each having similar overall efficacy. Of one hundred 'prototype' GPRs developed by the clinical guideline group, 85/100 were deemed 'appropriate' based on the independent scoring of a panel of 18 European experts and use of RAND-UCLA consensus methodology. The remaining 15 were all deemed uncertain. Future research recommendations included some potential RCTs but also a strong emphasis on delivery of large multinational high-quality prospective cohort studies.

CONCLUSION

While the evidence base for surgery in CC is poor, the widespread European consensus for GPRs is encouraging. Professional bodies have the opportunity to build on this work by supporting the efforts of their membership to help convert the documented recommendations into clinical guidelines.

Traditional measures of normal anal sphincter function using high-resolution anorectal manometry (HRAM) in 115 healthy volunteers

BACKGROUND

High-resolution anorectal manometry (HRAM) is a relatively new method for collection and interpretation of data relevant to sphincteric function, and for the first time allows a global appreciation of the anorectum as a functional unit. Historically, traditional anal manometry has been plagued by lack of standardization and healthy volunteer data of variable quality. The aims of this study were: (i) to obtain normative data sets for traditional measures of anorectal function using HRAM in healthy subjects and; (ii) to qualitatively describe novel physiological phenomena, which may be of future relevance when this method is applied to patients.

METHODS

115 healthy subjects (96 female) underwent HRAM using a 10 channel, 12F solid-state catheter. Measurements were performed during rest, squeeze, cough, and simulated defecation (push). Data were displayed as color contour plots and analysed using a commercially available manometric system (Solar GI HRM v9.1, Medical Measurement Systems). Associations between age, gender and parity were subsequently explored.

KEY RESULTS

HRAM color contour plots provided clear delineation of the high-pressure zone within the anal canal and showed recruitment during maneuvers that altered intra-anal pressures. Automated analysis produced quantitative data, which have been presented on the basis of gender and parity due to the effect of these covariates on some sphincter functions. In line with traditional manometry, some age and gender differences were seen. Males had a greater functional anal canal length and anal pressures during the cough maneuver. Parity in females was associated with reduced squeeze increments.

CONCLUSIONS & INFERENCES

The study provides a large healthy volunteer dataset and parameters of traditional measures of anorectal function. A number of novel phenomena are appreciated, the significance of which will require further analysis and comparisons with patient populations.

Systematic review of tibial nerve stimulation to treat faecal incontinence

Background

Two forms of tibial nerve stimulation are used to treat faecal incontinence (FI): percutaneous (PTNS) and transcutaneous (TTNS) tibial nerve stimulation. This article critically appraises the literature on both procedures.

Methods

A systematic review was performed adhering to the PRISMA framework. A comprehensive literature search was conducted, with systematic methodological quality assessment and data extraction. Summary measures for individual outcome variables are reported.

Results

Twelve articles met eligibility criteria; six related to PTNS, five to TTNS, and one to both procedures. These included ten case series and two randomized clinical trials (RCTs). Case series were evaluated using the National Institute for Health and Care Excellence quality assessment for case series, scoring 3–6 of 8. RCTs were evaluated using the Jadad score, scoring 4 of a possible 5 marks, and the Cochrane Collaboration bias assessment tool. From one RCT and case series reports, the success rate of PTNS, based on the proportion of patients who achieved a reduction in weekly FI episodes of at least 50 per cent, was 63–82 per cent, and that of TTNS was 0–45 per cent. In an RCT of TTNSversus sham, no patient had a reduction in weekly FI episodes of 50 per cent or more, whereas in an RCT of PTNSversus TTNSversus sham, 82 per cent of patients undergoing PTNS, 45 per cent of those having TTNS, and 13 per cent of patients in the sham group had treatment success.

Conclusion

PTNS and TTNS result in significant improvements in some outcome measures; however, TTNS was not superior to sham stimulation in a large, adequately powered, RCT. As no adequate RCT of PTNSversus sham has been conducted, conclusions cannot be drawn regarding this treatment.

Systematic review of the clinical effectiveness of neuromodulation in the treatment of faecal incontinence

BACKGROUND

Over the past 18 years neuromodulation therapies have gained support as treatments for faecal incontinence (FI); sacral nerve stimulation (SNS) is the most established of these. A systematic review was performed of current evidence regarding the clinical effectiveness of neuromodulation treatments for FI.

METHODS

The review adhered to the PRISMA framework. A comprehensive search of the literature included PubMed, MEDLINE, Embase and Evidence-Based Medicine Reviews. Methodological quality assessment and data extraction were completed in a systematic fashion.

RESULTS

For SNS, 321 citations were identified initially, of which 61 studies were eligible for inclusion. Of studies on other neuromodulation techniques, 11 were eligible for review: seven on percutaneous tibial nerve stimulation (PTNS) and four on transcutaneous tibial nerve stimulation (TTNS). On intention-to-treat, the median (range) success rates for SNS were 63 (33-66), 58 (52-81) and 54 (50-58) per cent in the short, medium and long terms respectively. The success rate for PTNS was 59 per cent at the longest reported follow-up of 12 months. SNS, PTNS and TTNS techniques also resulted in improvements in Cleveland Clinic Incontinence Score and quality-of-life measures. Despite significant use of neuromodulation in treatment of FI, there is still no consensus on outcome reporting in terms of measures used, aetiologies assessed, length of follow-up or assessment standards.

CONCLUSION

Emerging data for SNS suggest maintenance of its initial therapeutic effect into the long term. The clinical effectiveness of PTNS is comparable to that of SNS at 12 months, although there is no evidence to support its continued effectiveness after this period. PTNS may be a useful treatment before SNS. The clinical effectiveness of TTNS is still uncertain owing to the paucity of available evidence. A consensus to standardize the use of outcome measures is recommended in order that further reports can be compared meaningfully.

Competence assessment of senior vascular trainees using a carotid endarterectomy bench model

Background

Competency-based assessment is being introduced to surgical training. The value of bench-top technical skills assessment using a synthetic carotid endarterectomy (CEA) model was evaluated in vascular trainees and consultants.

Methods

Forty-one surgeons (13 junior trainees, 15 senior trainees and 13 experienced consultants with experience of more than 50 CEAs) performed a three-throw knot-tying exercise on a jig and a CEA on the bench model. A composite score for knot-tying was calculated, incorporating electromagnetic motion analysis. CEA technical skill was assessed using validated rating scales by blinded video analysis.

Results

Senior trainees performed better than junior trainees in knot-tying (P = 0·025) as well as generic (P < 0·001) and procedural (P < 0·001) skills on CEA model assessment. There was no difference between senior trainees and consultants on any of these measures. The CEA model interobserver reliability was high for all rating scales (generic α = 0·974, procedural α = 0·952, end-product α = 0·976).

Conclusion

Senior trainees achieved the same score as consultants, suggesting a similar level of basic technical skill and knowledge required to perform CEA, and were significantly better than junior trainees. Performance on the bench model could provide an early assessment for suitability to proceed to operative training in a competency-based training and assessment programme.