A systematic methodological review of non-randomised interventional studies of elective ventral hernia repair: clear definitions and a standardised minimum dataset are needed

Trends in Surgical Technique and Outcomes of Ventral Hernia Repair in The United States

OBJECTIVE

To describe national trends in surgical technique and rates of reoperation for recurrence for patients undergoing ventral hernia repair (VHR) in the United States.

BACKGROUND

Surgical options for VHR, including minimally invasive approaches, mesh implantation, and myofascial release, have expanded considerably over the past 2 decades. Their dissemination and impact on population-level outcomes is not well characterized.

METHODS

We conducted a retrospective cohort study of Medicare beneficiaries undergoing elective, inpatient umbilical, ventral, or incisional hernia repair between 2007 and 2015. Cox proportional hazards models were used to estimate the adjusted proportion of patients who remained free from reoperation for hernia recurrence up to 5 years after surgery.

RESULTS

One hundred fort-one thousand two hundred sixty-one patients underwent VHR during the study period. Between 2007 and 2018, the use of minimally invasive surgery increased from 2.1% to 22.2%, mesh use increased from 63.2% to 72.5%, and myofascial release increased from 1.8% to 16.3%. Overall, the 5-year incidence of reoperation for recurrence was 14.1% [95% confidence interval (CI) 14.0%-14.1%]. Over time, patients were more likely to remain free from reoperation for hernia recurrence 5 years after surgery [2007-2009 reoperation-free survival: 84.9% (95% CI 84.8%-84.9%); 2010-2012 reoperation-free survival: 85.7% (95% CI 85.6%-85.7%); 2013-2015 reoperation-free survival: 87.8% (95% CI 87.7%-87.9%)].

CONCLUSIONS

The surgical treatment of ventral and incisional hernias has evolved in recent decades, with more patients undergoing minimally invasive repair, receiving mesh, and undergoing myofascial release. Although our analysis does not address causality, rates of reoperation for hernia recurrence improved slightly contemporaneous with changes in surgical technique.

Biosynthetic meshes in contaminated fields: where are we now? A systematic review and meta-analysis in humans

PURPOSE

Selection of an appropriate mesh reinforcement for hernia repair in contaminated fields is a significant problem for surgeons. To date the proper mesh for contaminated fields has not been found. Biosynthetic meshes have emerged as new treatment option in contaminated fields. This study aims to evaluate the postoperative outcomes of biosynthetic meshes in contaminated fields.

METHODS

Systematic electronic search (PubMed, Medline, Embase, Scopus), according to PRISMA criteria, was performed. A literature search of scientific papers was performed by two reviewers until April 2021. Articles were chosen based on reference to biosynthetic meshes, their use in infected fields, and in human subjects. GRADE methodology and the modified Newcastle-Ottawa scale were used to assess the quality of studies. According to CDC-Centers for Disease Control classes patients were divided into two subgroups, group 1 (CDC class 2) and group 2 (CDC classes 3-4).

RESULTS

The research included 21 articles and 1619 patients were analyzed. Long-term follow-up showed a significant higher recurrence rate than short-term follow-up. P < 0.001. Meta-analysis of these studies showed that the SSI were significantly higher in CDC classes 3-4 than CDC class 2 (P < 0.01). No differences were found in SSO (P = 0.06) and recurrence (P = 0.37) rate among the two groups. Phasix™ was the most common mesh in 15 studies. The mean follow-up was 23.0 months. The surgical site infection (SSI) rate was 17.3%. The surgical site occurrence (SSO) rate was 32.4%. Recurrence rate was 11.5%.

CONCLUSION

This is the first systematic review and meta-analysis on the clinical outcomes of abdominal wall repair using biosynthetic mesh in contaminated-infected settings. The results show good results in patients at high risk of postoperative wound complications. The aim of this study is to add to the growing literature on biosynthetic mesh a picture of current literature evidence to help future researchers performing further studies on this topic.

Perioperative optimization in complex abdominal wall hernias: Delphi consensus statement

BACKGROUND

The incidence of incisional hernia after major abdominal surgery via a midline laparotomy is 20-41 per cent with short-term follow-up, and over 50 per cent in those surviving an abdominal catastrophe. Abdominal wall reconstruction (AWR) requires complex operations, often involving mesh resection, management of scarred skin, fistula takedown, component separation or flap reconstruction. Patients tend to have more complex conditions, with multiple co-morbidities predisposing them to a vicious cycle of complications and, subsequently, hernia recurrence. Currently there appears to be variance in perioperative practice and minimal guidance globally. The aim of this Delphi consensus was to provide a clear benchmark of care for the preoperative assessment and perioperative optimization of patients undergoing AWR.

METHODS

The Delphi method was used to achieve consensus from invited experts in the field of AWR. Thirty-two hernia surgeons from recognized hernia societies globally took part. The process included two rounds of anonymous web-based voting with response analysis and formal feedback, concluding with a live round of voting followed by discussion at an international conference. Consensus for a strong recommendation was achieved with 80 per cent agreement, and a weak recommendation with 75 per cent agreement.

RESULTS

Consensus was obtained on 52 statements including surgical assessment, preoperative assessment, perioperative optimization, multidisciplinary team and decision-making, and quality-of-life assessment. Forty-six achieved over 80 per cent agreement; 14 statements achieved over 95 per cent agreement.

CONCLUSION

Clear consensus recommendations from a global group of experts in the AWR field are presented in this study. These should be used as a baseline for surgeons and centres managing abdominal wall hernias and performing complex AWR.

Reporting guideline for interventional trials of primary and incisional ventral hernia repair

BACKGROUND

Primary and incisional ventral hernia trials collect unstandardized inconsistent data, limiting data interpretation and comparison. This study aimed to create two minimum data sets for primary and incisional ventral hernia interventional trials to standardize data collection and improve trial comparison. To support these data sets, standardized patient-reported outcome measures and trial methodology criteria were created.

METHODS

To construct these data sets, nominal group technique methodology was employed, involving 15 internationally recognized abdominal wall surgeons and two patient representatives. Initially a maximum data set was created from previous systematic and panellist reviews. Thereafter, three stages of voting took place: stage 1, selection of the number of variables for data set inclusion; stage 2, selection of variables to be included; and stage 3, selection of variable definitions and detection methods. A steering committee interpreted and analysed the data.

RESULTS

The maximum data set contained 245 variables. The three stages of voting commenced in October 2019 and had been completed by July 2020. The final primary ventral hernia data set included 32 variables, the incisional ventral hernia data set included 40 variables, the patient-reported outcome measures tool contained 25 questions, and 40 methodological criteria were chosen. The best known variable definitions were selected for accurate variable description. CT was selected as the optimal preoperative descriptor of hernia morphology. Standardized follow-up at 30 days, 1 year, and 5 years was selected.

CONCLUSION

These minimum data sets, patient-reported outcome measures, and methodological criteria have allowed creation of a manual for investigators aiming to undertake primary ventral hernia or incisional ventral hernia interventional trials. Adopting these data sets will improve trial methods and comparisons.

A systematic review of outcome reporting in incisional hernia surgery

Background

The incidence of incisional hernia is up to 20 per cent after abdominal surgery. The management of patients with incisional hernia can be complex with an array of techniques and meshes available. Ensuring consistency in reporting outcomes across studies on incisional hernia is important and will enable appropriate interpretation, comparison and data synthesis across a range of clinical and operative treatment strategies.

Methods

Literature searches were performed in MEDLINE and EMBASE (from 1 January 2010 to 31 December 2019) and the Cochrane Central Register of Controlled Trials. All studies documenting clinical and patient-reported outcomes for incisional hernia were included.

Results

In total, 1340 studies were screened, of which 92 were included, reporting outcomes on 12 292 patients undergoing incisional hernia repair. Eight broad-based outcome domains were identified, including patient and clinical demographics, hernia-related symptoms, hernia morphology, recurrent incisional hernia, operative variables, postoperative variables, follow-up and patient-reported outcomes. Clinical outcomes such as hernia recurrence rates were reported in 80 studies (87 per cent). A total of nine different definitions for detecting hernia recurrence were identified. Patient-reported outcomes were reported in 31 studies (34 per cent), with 18 different assessment measures used.

Conclusions

This review demonstrates the significant heterogeneity in outcome reporting in incisional hernia studies, with significant variation in outcome assessment and definitions. This is coupled with significant under-reporting of patient-reported outcomes.

Measuring quality of life in patients with abdominal wall hernias: a systematic review of available tools

INTRODUCTION

Abdominal wall herniation (AWH) is an increasing problem for patients, surgeons, and healthcare providers. Surgical-site specific outcomes, such as infection, recurrence, and mesh explantation, are improving; however, successful repair still exposes the patient to what is often a complex major operation aimed at improving quality of life. Quality-of-life (QOL) outcomes, such as aesthetics, pain, and physical and emotional functioning, are less often and less well reported. We reviewed QOL tools currently available to evaluate their suitability.

METHODS

A systematic review of the literature in compliance with PRISMA guidelines was performed between 1st January 1990 and 1st May 2019. English language studies using validated quality-of-life assessment tool, whereby outcomes using this tool could be assessed were included.

RESULTS

Heterogeneity in the QOL tool used for reporting outcome was evident throughout the articles reviewed. AWH disease-specific tools, hernia-specific tools, and generic tools were used throughout the literature with no obviously preferred or dominant method identified.

CONCLUSION

Despite increasing acknowledgement of the need to evaluate QOL in patients with AWH, no tool has become dominant in this field. Assessment, therefore, of the impact of certain interventions or techniques on quality of life remains difficult and will continue to do so until an adequate standardised outcome measurement tool is available.

Bioabsorbable mesh use in midline abdominal wall prophylaxis and repair achieving fascial closure: a cross-sectional review of stage of innovation

BACKGROUND

Achieving stable closure of complex or contaminated abdominal wall incisions remains challenging. This study aimed to characterise the stage of innovation for bioabsorbable mesh devices used during both midline closure prophylaxis and complex abdominal wall reconstruction and to evaluate the quality of current evidence.

METHODS

A systematic review of published and ongoing studies was performed until 31st December 2019. Inclusion criteria were studies where bioabsorbable mesh was used to support fascial closure either prophylactically after midline laparotomy or for repair of incisional hernia with midline incision. Exclusion criteria were: (1) study design was a systematic review, meta-analysis, letter, review, comment, or conference abstract; (2) included less than p patients; (3) only evaluated biological, synthetic or composite meshes. The primary outcome measure was the IDEAL framework stage of innovation. The key secondary outcome measure was the risk of bias in non-randomised studies of interventions (ROBINS-I) criteria for study quality.

RESULTS

Twelve studies including 1287 patients were included. Three studies considered mesh prophylaxis and nine studies considered hernia repair. There were only two published studies of IDEAL 2B. The remainder was IDEAL 2A studies. The quality of the evidence was categorised as having a risk of bias of a moderate, serious or critical level in nine of the twelve included studies using the ROBINS-I tool.

CONCLUSION

The evidence base for bioabsorbable mesh is limited. Better reporting and quality control of surgical techniques are needed. Although new trial results over the next decade will improve the evidence base, more trials in emergency and contaminated settings are required to establish the limits of indication.

A tutorial on methodological studies: the what, when, how and why

BACKGROUND

Methodological studies - studies that evaluate the design, analysis or reporting of other research-related reports - play an important role in health research. They help to highlight issues in the conduct of research with the aim of improving health research methodology, and ultimately reducing research waste.

MAIN BODY

We provide an overview of some of the key aspects of methodological studies such as what they are, and when, how and why they are done. We adopt a "frequently asked questions" format to facilitate reading this paper and provide multiple examples to help guide researchers interested in conducting methodological studies. Some of the topics addressed include: is it necessary to publish a study protocol? How to select relevant research reports and databases for a methodological study? What approaches to data extraction and statistical analysis should be considered when conducting a methodological study? What are potential threats to validity and is there a way to appraise the quality of methodological studies?

CONCLUSION

Appropriate reflection and application of basic principles of epidemiology and biostatistics are required in the design and analysis of methodological studies. This paper provides an introduction for further discussion about the conduct of methodological studies.