The economic burden of incisional ventral hernia repair: a multicentric cost analysis

TACKoMesh - A randomised controlled trial comparing absorbable versus non-absorbable tack fixation in laparoscopic IPOM + repair of primary incisional hernia using post-operative pain and quality of life - Reliatack™ versus Protack™

There is a clinical need to better understand and improve post-operative pain for patients undergoing laparoscopic repair of incisional hernia. The aim of this single-centre, double-blind, randomised controlled trial was to compare post-operative pain between absorbable and non-absorbable tack fixation in patients undergoing IPOM + repair. Patients with primary incisional hernia (size 3-10 cm), were randomised to either Reliatack™ (n = 27), an articulating-arm device deploying absorbable polymer tacks, or Protack™ (n = 36), a straight-arm device deploying permanent titanium tacks. The primary outcome was reported pain on activity using a visual analogue scale at post-operative day 30. Clinical and patient-reported outcome measures (PROMs) were assessed pre-operatively (day 0), and at 1-, 6-, 30- and 365-days post-surgery. No significant differences in reported pain 'on activity' were found at any timepoint. Less reported pain 'at rest' was found on post-operative day-1 with absorbable tacks (p = 0.020). Significantly longer mesh-fixation time (p < 0.001) and the use of more knots for fascial closure (p = 0.006) and tacks for mesh-fixation (p = 0.001) were found for the absorbable tack group. There were no differences in other clinical and PROMs between groups. For the whole trial cohort (n = 63) several domains in the Short-Form-36 showed a reduction from baseline scores at day 30 that improved at day 365. At post-operative day 30, 75.0% of patients reported 'a lot of pain' since discharge. This study found no difference in reported pain when choosing absorbable or non-absorbable tack fixation. The utility of "early" post-operative pain assessment as a comparator following incisional hernia repair needs clarification.

Impact of small-bite (5 mm) fascial closure on the incidence of incisional hernia following open colorectal cancer surgery: randomized clinical trial

BACKGROUND

Incisional hernia is frequently observed after open colorectal cancer surgery, and should be considered a serious short- and long-term health issue. The present study evaluated the efficacy of small-bite abdominal closure in reducing the incidence of incisional hernia in this patient group.

METHODS

An RCT was conducted between June 2019 and June 2022. A total of 173 patients who underwent open colorectal cancer surgery were assigned randomly to one of two groups to undergo fascial closure with either small bites (87) or conventional bites (86). The incisional hernia rate was accepted as the primary outcome, and surgical-site infection as the secondary outcome.

RESULTS

The incisional hernia rates at 1 year were 7 and 27% in the small- and conventional-bite groups respectively (P < 0.001). This rate increased to 9 and 31% at the end of the second year (P < 0.001). Surgical-site infections occurred in 18% of the small-bite group and 31% of the conventional-bite group (P = 0.03). Compared with the conventional-bite group, the small-bite group had higher suture/wound length ratios (mean(s.d.) 5.18(0.84) versus 3.67(0.57); P < 0.001) and a longer fascial closure time 14.1(4.64) versus 12.9(2.39) min; P = 0.03).

CONCLUSION

Small-bite closure with 5-mm tissue bites placed 5 mm apart reduced the incidence of incisional hernia and surgical-site infection after open colorectal cancer surgery.

Linking factors to incisional hernia following pancreatic surgery: a 14-year retrospective analysis

BACKGROUND

Incisional hernias (IH) are a significant postoperative complication with profound implications for patient morbidity and healthcare costs. The relationship between IH and perioperative factors in pancreatic surgery, with particular attention to preoperative biliary stents and pancreatic fistulas requires further exploration.

METHODS

This retrospective observational study examined adult patients who underwent open pancreatic surgeries via midline incision at a high-volume tertiary hepatopancreatobiliary center from January 2008 to December 2021. The study focused on IH incidence and associated risk factors, with particular attention to preoperative biliary stents and pancreatic fistulas.

RESULTS

In a cohort of 620 individuals undergoing pancreatic surgery, 351 had open surgery with at least one-year follow-up. Within a median follow-up of 794 days (IQR 1694-537), the overall incidence of IH was 17.38%. The highest frequency of IH was observed among patients who had a Pancreaticoduodenectomy (PD). Significant predictors for the development of IH within the entire study population in a multivariable analysis included perioperative biliary stenting (OR 2.05; 95% CI 1.06-3.96; p = 0.03), increased age at diagnosis (OR 2.05; 95% CI 1.06-3.96; p = 0.01), and BMI (OR 1.08; 95% CI 1.01-1.15; p = 0.01). In the subset of patients who underwent Pancreaticoduodenectomy (PD), although the presence of biliary stents was associated with a heightened occurrence of SSIs, it did not demonstrate a direct correlation with an increased incidence of incisional hernias (IH). The development of pancreatic fistulas did not show a significant correlation with IH in either the Distal Pancreatectomy with Splenectomy (DPS) or the PD patient groups.

CONCLUSIONS

The study underscores a notable association between biliary stent placement and increased IH risk after PD, mediated by elevated SSI incidence. Pancreatic fistulas were not directly correlated with IH in the studied cohorts. Further research is necessary to validate these findings and guide clinical practice.

Effect of Specimen Extraction Site on Postoperative Incisional Hernia after Minimally Invasive Right Colectomy

BACKGROUND

Incisional hernia (IH) is a known complication after colorectal surgery. Despite advances in minimally invasive surgery, colorectal surgery still requires extraction sites for specimen retrieval, increasing the likelihood of postoperative IH development. The objective of this study is to determine the effect of specimen extraction site on the rate of IH after minimally invasive right-sided colectomy for patients with available imaging.

STUDY DESIGN

This is a retrospective multi-institutional cohort study at 2 large academic medical centers in the US. Adults who underwent right-sided minimally invasive colectomy from 2012 to 2020 with abdominal imaging available at least 1 year postoperatively were included in the analysis. The primary exposure was specimen extraction via a midline specimen extraction vs Pfannenstiel specimen extraction. The main outcome was the development of IH at least 1 year postoperatively as visualized on a CT scan.

RESULTS

Of the 341 patients sampled, 194 (57%) had midline specimen extraction and 147 (43%) had a Pfannenstiel specimen extraction. Midline extraction patients were older (66 ± 15 vs 58 ± 16; p < 0.001) and had a higher rate of previous abdominal operation (99, 51% vs 55, 37%, p = 0.01). The rate of IH was higher in midline extraction at 25% (48) compared with Pfannenstiel extraction (0, 0%; p < 0.001). The average length of stay was higher in the midline extraction group at 5.1 ± 2.5 compared with 3.4 ± 3.1 days in the Pfannenstiel extraction group (p < 0.001). Midline extraction was associated with IH development (odds ratio 24.6; 95% CI 1.89 to 319.44; p = 0.004). Extracorporeal anastomosis was associated with a higher IH rate (odds ratio 25.8; 95% CI 2.10 to 325.71; p = 0.002).

CONCLUSIONS

Patients who undergo Pfannenstiel specimen extraction have a lower risk of IH development compared with those who undergo midline specimen extraction.

Recent Advances in Functional Hydrogel for Repair of Abdominal Wall Defects: A Review

The abdominal wall plays a crucial role in safeguarding the internal organs of the body, serving as an essential protective barrier. Defects in the abdominal wall are common due to surgery, infection, or trauma. Complex defects have limited self-healing capacity and require external intervention. Traditional treatments have drawbacks, and biomaterials have not fully achieved the desired outcomes. Hydrogel has emerged as a promising strategy that is extensively studied and applied in promoting tissue regeneration by filling or repairing damaged tissue due to its unique properties. This review summarizes the five prominent properties and advances in using hydrogels to enhance the healing and repair of abdominal wall defects: (a) good biocompatibility with host tissues that reduces adverse reactions and immune responses while supporting cell adhesion migration proliferation; (b) tunable mechanical properties matching those of the abdominal wall that adapt to normal movement deformations while reducing tissue stress, thereby influencing regulating cell behavior tissue regeneration; (c) drug carriers continuously delivering drugs and bioactive molecules to sites optimizing healing processes enhancing tissue regeneration; (d) promotion of cell interactions by simulating hydrated extracellular matrix environments, providing physical support, space, and cues for cell migration, adhesion, and proliferation; (e) easy manipulation and application in surgical procedures, allowing precise placement and close adhesion to the defective abdominal wall, providing mechanical support. Additionally, the advances of hydrogels for repairing defects in the abdominal wall are also mentioned. Finally, an overview is provided on the current obstacles and constraints faced by hydrogels, along with potential prospects in the repair of abdominal wall defects.

Obesity increases the surgical complexity and risk of recurrence after midline primary ventral hernia repair: results on 2307 patients from the French Society of hernia surgery (SFCP-CH) registry database

PURPOSE

Obesity is a known risk factor of recurrence after hernia surgery, but available data often concern pooled cases of primary and incisional hernia, with short follow-up. We aimed to analyze the impact of severe obesity (BMI ≥ 35 kg/m2) on the results of midline primary ventral hernia repair (mPVHR), in comparison with non-severely obese patients.

METHODS

Data were extracted from a multicentric registry, in which patients' data are consecutively and anonymously collected. We conducted a retrospective comparative study on patients with severe obesity (sOb) versus non-severely obese patients (non-sOb), who underwent surgery, with a minimal 2-year follow-up after their mPVHR.

RESULTS

Among 2307 patients, 267 sOb and 2040 non-sOb matched inclusion criteria. Compared with non-sOb, sOb group gathered all the worse conditions and risk factors: more ASA3-4 (39.3% vs. 10.2%; p < 0.001), symptomatic hernia (15.7% vs. 6.8%; p < 0.001), defect > 4 cm in diameter (24.3% vs. 8.8%; p < 0.001), emergency surgery (6.1% vs. 2.5%; p = 0.003), and Altemeir class > 1 (9.4% vs. 2.9%; p < 0.001). Laparoscopic IPOM was used more often in sOb patients (40% vs. 32%; p = 0.016), but with smaller Hauters' ratio (46 vs. 73; p < 0.001). Compared with the non-sOb, the rate of day-case surgery was lower (48% vs. 68%; p < 0.001), the surgical site occurrences were significantly more frequent (6.4 %vs. 2.5%; p < 0.001). The main outcome, 2-year recurrence, was 5.9% in the sOb vs. 2.1% (p = 0.008), and 2-year reoperations was 3% vs. 0.3% (p = 0.006). In the adjusted analysis, severe obesity was an independent risk factor for recurrence [OR = 2.82, (95%CI, 1.45; 5.22); p = 0.003].

CONCLUSION

In patients with severe obesity, mPVHR is technically challenging and recurrence rate is three times higher than that of non-severely obese patients.

Double-Layer Asymmetric Porous Mesh with Dynamic Mechanical Support Properties Enables Efficient Single-Stage Repair of Contaminated Abdominal Wall Defect

Contamination tolerance and long-term mechanical support are the two critical properties of meshes for contaminated abdominal wall defect repair. However, biological meshes with excellent pollution tolerance fail to provide bio-adaptive long-term mechanical support due to their rapid degradation. Here, a novel double-layer asymmetric porous mesh (SIS/PVA-EXO) is designed by simple and efficient in situ freeze-thaw of sticky polyvinyl alcohol (PVA) solution on the loosely porous surface of small intestinal submucosal decellularized matrix (SIS), which can successfully repair the contaminated abdominal wall defect with bio-adaptive dynamic mechanical support through only single-stage surgery. The exosome-loaded degradable loosely porous SIS layer accelerates the tissue healing; meanwhile, the exosome-loaded densely porous PVA layer can maintain long-term mechanical support without any abdominal adhesion. In addition, the tensile strength and strain at break of SIS/PVA-EXO mesh change gradually from 0.37 MPa and 210% to 0.10 MPa and 385% with the degradation of SIS layer. This unique performance can dynamically adapt to the variable mechanical demands during different periods of contaminated abdominal wall reconstruction. As a result, this SIS/PVA-EXO mesh shows an attractive prospect in the treatment of contaminated abdominal wall defect without recurrence by integrating local immune regulation, tissue remodeling, and dynamic mechanical supporting.

Short-term outcomes of a multicentre prospective study using a "visible" polyvinylidene fluoride onlay mesh for the prevention of midline incisional hernia

INTRODUCTION

Prophylactic meshes in high-risk patients prevent incisional hernias, although there are still some concerns about the best layer to place them in, the type of fixation, the mesh material, the significance of the level of contamination, and surgical complications. We aimed to provide answers to these questions and information about how the implanted material behaves based on its visibility under magnetic resonance imaging (MRI).

METHOD

This is a prospective multicentre observational cohort study. Preliminary results from the first 3 months are presented. We included general surgical patients who had at least two risk factors for developing an incisional hernia. Multivariate logistic regression was used. A polyvinylidene fluoride (PVDF) mesh loaded with iron particles was used in an onlay position. MRIs were performed 6 weeks after treatment.

RESULTS

Between July 2016 and June 2022, 185 patients were enrolled in the study. Surgery was emergent in 30.3% of cases, contaminated in 10.7% and dirty in 11.8%. A total of 5.6% of cases had postoperative wound infections, with the requirement of stoma being the only significant risk factor (OR = 7.59, p = 0.03). The formation of a seroma at 6 weeks detected by MRI, was associated with body mass index (OR = 1.13, p = 0.02).

CONCLUSIONS

The prophylactic use of onlay PVDF mesh in midline laparotomies in high-risk patients was safe and effective in the short term, regardless of the type of surgery or the level of contamination. MRI allowed us to detect asymptomatic seromas during the early process of integration.

STUDY REGISTRATION

 This protocol was registered at ClinicalTrials.gov (NCT03105895).

Protocol for an independent patient data meta-analysis of prophylactic mesh placement for incisional hernia prevention after abdominal aortic aneurysm surgery: a collaborative European Hernia Society project (I-PREVENT-AAA)

INTRODUCTION

Incisional hernia (IH) is a prevalent and potentially dangerous complication of abdominal surgery, especially in high-risk groups. Mesh reinforcement of the abdominal wall has been studied as a potential intervention to prevent IHs. Randomised controlled trials (RCTs) have demonstrated that prophylactic mesh reinforcement after abdominal surgery, in general, is effective and safe. In patients with abdominal aortic aneurysm (AAA), prophylactic mesh reinforcement after open repair has not yet been recommended in official guidelines, because of relatively small sample sizes in individual trials. Furthermore, the identification of subgroups that benefit most from prophylactic mesh placement requires larger patient numbers. Our primary aim is to evaluate the efficacy and effectiveness of the use of a prophylactic mesh after open AAA surgery to prevent IH by performing an individual patient data meta-analysis (IPDMA). Secondary aims include the evaluation of postoperative complications, pain and quality of life, and the identification of potential subgroups that benefit most from prophylactic mesh reinforcement.

METHODS AND ANALYSIS

We will conduct a systematic review to identify RCTs that study prophylactic mesh placement after open AAA surgery. Cochrane Central Register of Controlled Trials, MEDLINE Ovid, Embase, Web of Science Core Collection and Google Scholar will be searched from the date of inception onwards. RCTs must directly compare primary sutured closure with mesh closure in adult patients who undergo open AAA surgery. Lead authors of eligible studies will be asked to share individual participant data (IPD). The risk of bias (ROB) for each included study will be assessed using the Cochrane ROB tool. An IPDMA will be performed to evaluate the efficacy, with the IH rate as the primary outcome. Any signs of heterogeneity will be evaluated by Forest plots. Time-to-event analyses are performed using Cox regression analysis to evaluate risk factors.

ETHICS AND DISSEMINATION

No new data will be collected in this study. We will adhere to institutional, national and international regulations regarding the secure and confidential sharing of IPD, addressing ethics as indicated. We will disseminate findings via international conferences, open-source publications in peer-reviewed journals and summaries posted online.

PROSPERO REGISTRATION NUMBER

CRD42022347881.

Component separation repair of incisional hernia: evolution of practice and review of long-term outcomes in a single center

PURPOSE

To review the long-term outcomes of complex abdominal wall reconstruction using anterior and posterior component separation (CS) techniques in our center.

METHODS

This was a descriptive analytical study. Analysis of data from a prospectively collected database of patients who had undergone Component Separation (CS) repair of incisional hernias was performed. Two techniques were used. Anterior component separation (ACS) and posterior component separation with transversus abdominis release (PCS/TAR). Follow-up was clinical review at 6 weeks, 6 months, and 12 months with direct access telephone review thereafter. Long-term outcome data was obtained from electronic records and based on either clinical or CT assessment. Minimum physical follow-up was 6 months for all patients.

RESULTS

89 patients with large incisional hernias underwent CS repair. 29 patients had ACS while 60 underwent PCS/TAR. Mean follow-up was 60 months (range 6-140 months) in the ACS group and 20 months (range 6-72 months) in the PCS group. Twenty-five patients (28%) had simultaneous major procedures including 21 intestinal anastomoses. Twenty-six (29%) of patients had associated stomas. Twenty-seven (30.3%) of the patients had undergone previous hernia repairs. Seromas occurred in 24 (26.97%) patients. Wound infections were more common after ACS. There have been 10 (11.2%) recurrences to date.

CONCLUSION

Component separation repair techniques result in good long-term outcomes with acceptable complication rates. They can be performed simultaneously with gastrointestinal procedures with low morbidity. Appropriate patient selection and use of appropriate mesh are important.

Strength of small-bites abdominal wall closure using different suturing methods and materials in an experimental animal model

PURPOSE

Using small instead of large bites for laparotomy closure results in lower incidence of incisional hernia, but no consensus exists on which suture material to use. This study aimed to compare five different closure strategies in a standardized experimental setting.

METHODS

Fifty porcine abdominal walls were arranged into 5 groups: (A) running 2/0 polydioxanone; (B) interlocking 2/0 polydioxanone; (C) running size 0 barbed polydioxanone; (D) running size 0 barbed glycolic acid and trimethylene carbonate; (E) running size 0 suturable polypropylene mesh. The small-bites technique was used for linea alba closure in all. The abdominal walls were divided into a supra- and infra-umbilical half, resulting in 20 specimens per group that were pulled apart in a tensile testing machine. Maximum tensile force and types of suture failure were registered.

RESULTS

The highest tensile force was measured when using barbed polydioxanone (334.8 N ± 157.0), but differences did not reach statistical significance. Infra-umbilical abdominal walls endured a significantly higher maximum tensile force compared to supra-umbilical (397 N vs 271 N, p < 0.001). Barbed glycolic acid and trimethylene carbonate failed significantly more often (25% vs 0%, p = 0.008).

CONCLUSION

Based on tensile force, both interlocking and running suture techniques using polydioxanone, and running sutures using barbed polydioxanone or suturable mesh, seem to be suitable for abdominal wall closure. Tensile strength was significantly higher in infra-umbilical abdominal walls compared to supra-umbilical. Barbed glycolic acid and trimethylene carbonate should probably be discouraged for fascial closure, because of increased risk of suture failure.

The enigma of incisional hernia prediction unraveled: external validation of a prognostic model in colorectal cancer patients

PURPOSE

Accurate prediction of hernia occurrence is vital for surgical decision-making and patient management, particularly in colorectal surgery patients. While a hernia prediction model has been developed, its performance in external populations remain to be investigated. This study aims to validate the existing model on an external dataset of patients who underwent colorectal surgery.

METHODS

The "Penn Hernia Calculator" model was externally validated using the Hughes Abdominal Repair Trial (HART) data, a randomized trial comparing colorectal cancer surgery closure techniques. The data encompassed demographics, comorbidities, and surgical specifics. Patients without complete follow-up were omitted. Model performance was assessed using key metrics, including area under the curve (AUC-ROC and AUC-PR) and Brier score. Reporting followed the TRIPOD consensus.

RESULTS

An external international dataset consisting of 802 colorectal surgery patients were identified, of which 674 patients with up to 2 years follow-up were included. Average patient age was 68 years, with 63.8% male. The average BMI was 28.1. Prevalence of diabetes, hypertension, and smoking were 15.7%, 16.3%, and 36.5%, respectively. Additionally, 7.9% of patients had a previous hernia. The most common operation types were low anterior resection (35.3%) and right hemicolectomy (34.4%). Hernia were observed in 24% of cases by 2-year follow-up. The external validation model revealed an AUC-ROC of 0.66, AUC-PR of 0.72, and a Brier score of 0.2.

CONCLUSION

The hernia prediction model demonstrated moderate performance in the external validation. Its potential generalizability, specifically in those undergoing colorectal surgery, may suggest utility in identifying and managing high-risk hernia candidates.

External validation and revision of Penn incisional hernia prediction model: A large-scale retrospective cohort of abdominal operations

BACKGROUND

Incisional hernia (IH) manifests in 10%-15% of abdominal surgeries and patients at elevated risk of this complication should be identified for prophylactic intervention. This study aimed to externally validate the Penn hernia risk calculator.

METHODS

The Ramathibodi abdominal surgery cohort was constructed by linking relevant hospital databases from 2010 to 2021. Penn hernia risk scores were calculated according to the original model which was externally validated using a seven-step approach. An updated model which included four additional predictor variables (i.e., age, immunosuppressive medication, ostomy reversal, and transfusion) added to those of the three original predictors (i.e., body mass index, chronic liver disease, and open surgery) was also evaluated. The area under the receiver operating characteristic curve (AUC) was estimated, and calibration performance was compared using the Hosmer-Lemeshow goodness-of-fit method for the observed/expected (O/E) ratio.

RESULTS

A total of 12,155 abdominal operations were assessed. The original Penn model yielded fair discrimination with an AUC (95% confidence interval (CI)) of 0.645 (0.607, 0.683). The updated model that included the additional predictor variables achieved an acceptable AUC (95% CI) of 0.733 (0.698, 0.768) with the O/E ratio of 0.968 (0.848, 1.088).

CONCLUSION

The updated model achieved improved discrimination and calibration performance, and should be considered for the identification of high-risk patients for further hernia prevention strategy.

A Prospective Randomized Controlled Trial Comparing Clinical Equivalence of PD Synth and PDS Polydioxanone Sutures

Introduction Incisional hernia is a common complication of midline laparotomy that may develop even after several years of surgery. Abdominal fascia closure with ideal suture material reduces the incidence of incisional hernia. This study compared the clinical equivalence of PD Synth (Healthium Medtech Limited) and PDS (Ethicon, Johnson & Johnson) slowly absorbed polydioxanone suture with respect to the occurrence of incisional hernia, following elective/emergency midline laparotomy. Methods Eighty-eight subjects undergoing elective/emergency midline laparotomy were randomized to PD Synth (n=45) and PDS (n=43) groups of this prospective, multicenter, randomized (1:1), single-blind, two-arm, parallel-group study (December 2020-May 2023). Primary endpoint was incidence of incisional hernia, occurring within six and 12 months of surgery. Secondary endpoints included incidence of fascial dehiscence, surgical site infection (SSI), suture sinus, seroma, hematoma, scar tenderness, and re-suturing, and evaluation of operative data, hospital stay, intra-operative suture handling, pain, time to return to normal day-to-day activities and work, overall patient satisfaction score, and adverse events. Results One subject in both PD Synth and PDS groups (p>0.05) developed incisional hernia at umbilicus 12 months post-laparotomy. In PDS group, one subject each had incidences of SSI on day 2, day 7, and one month, two subjects developed seroma on day seven, and one subject had readmission on one month; two subjects in PD Synth group developed superficial SSI (one month). Findings of other secondary endpoints were comparable between the groups. Conclusion Primary and secondary outcomes manifested that PD Synth and PDS slowly absorbed polydioxanone sutures are clinically equivalent, and can be used for abdominal fascial closure following midline laparotomy.

Incisional Hernia: A Surgical Complication or Medical Disease?

Incisional hernia (IH) is a frequent complication following abdominal surgery. The development of IH could be more sophisticated than a simple anatomical failure of the abdominal wall. Reported IH incidence varies among studies. This review presented an overview of definitions, molecular basis, risk factors, incidence, clinical presentation, surgical techniques, postoperative care, cost, risk prediction tools, and proposed preventative measures. A literature search of PubMed was conducted to include high-quality studies on IH. The incidence of IH depends on the primary surgical pathology, incision site and extent, associated medical comorbidities, and risk factors. The review highlighted inherent and modifiable risk factors. The disorganisation of the extracellular matrix, defective fibroblast functions, and ratio variations of different collagen types are implicated in molecular mechanisms. Elective repair of IH alleviates symptoms, prevents complications, and improves the quality of life (QOL). Recent studies introduced risk prediction tools to implement preventative measures, including suture line reinforcement or prophylactic mesh application in high-risk groups. Elective repair improves QOL and prevents sinister outcomes associated with emergency IH repair. The watchful wait strategy should be reviewed, and options should be discussed thoroughly during patients' counselling. Risk stratification tools for predicting IH would help adopt prophylactic measures.

A Zwitterionic Hydrogel with Anti-Oxidative and Anti-Inflammatory Properties for the Prevention of Peritoneal Adhesion by Inhibiting Mesothelial-Mesenchymal Transition

Postoperative peritoneal adhesion is a serious clinical complication. Various hydrogel barriers have been developed to prevent peritoneal adhesion. However, it remains a challenge to design a hydrogel with desirable physicochemical properties and bioactivities. In this study, a zwitterionic polysaccharide-based multifunctional hydrogel is developed using epigallocatechin-3-gallate (EGCG) to prevent postoperative abdominal adhesion. This hydrogel is simple to use and has desirable properties, such as excellent injectability, self-healing, and non-swelling properties. The hydrogel also has ultralow fouling capabilities, such as superior bactericidal performance, cell and protein adhesion, and low immunogenicity resistance. Moreover, the hydrogel exhibits good antioxidant activity, which is attributed to the integration of EGCG. Furthermore, the detailed mechanism from in vivo and in vitro experimental studies illustrates that hydrogel compositions can synergistically prevent adhesion formation through multiple pathways, including anti-inflammatory and antioxidant capabilities and inhibition effects on the mesothelial-mesenchymal transition (MMT) process induced by transforming growth factor (TGF-β). In summary, this zwitterionic multifunctional hydrogel has great potential to prevent postoperative adhesion formation in the clinical setting.

Killing two birds with one stone: A therapeutic copper-loaded bio-patch promoted abdominal wall repair via VEGF pathway

Hernia and life-threatening intestinal obstruction often result from abdominal wall injuries, and the regeneration of abdominal wall defects is limited due to the lack of biocompatible, antibacterial and angiogenic scaffolding materials for treating injured tissues. Taking inspiration from the facile preparation of dopamine polymerization and its surface modification technology, in this study, multi-therapeutic copper element was introduced into porcine small intestinal submucosa (SIS) bio-patches through polydopamine (PDA) deposition, in order to regenerate abdominal wall injury. In both in vitro antibacterial assays, cytocompatibility assays and in vivo abdominal wall repair experiments, the SIS/PDA/Cu bio-patches exhibited robust antibacterial efficiency (＞99%), excellent biocompatibility to cells (＞90%), and enhanced neovascularization and improved collagen maturity compared to other commercially available patches (3.0-fold higher than the PP mesh), due to their activation of VEGF pathway. These findings indicated the bio-patch was a promising application for preventing visceral adhesion, bacterial infection, and promoting soft tissue regeneration.

Abdominal wall hernia repair: from prosthetic meshes to smart materials

Hernia reconstruction is one of the most frequently practiced surgical procedures worldwide. Plastic surgery plays a pivotal role in reestablishing desired abdominal wall structure and function without the drawbacks traditionally associated with general surgery as excessive tension, postoperative pain, poor repair outcomes, and frequent recurrence. Surgical meshes have been the preferential choice for abdominal wall hernia repair to achieve the physical integrity and equivalent components of musculofascial layers. Despite the relevant progress in recent years, there are still unsolved challenges in surgical mesh design and complication settlement. This review provides a systemic summary of the hernia surgical mesh development deeply related to abdominal wall hernia pathology and classification. Commercial meshes, the first-generation prosthetic materials, and the most commonly used repair materials in the clinic are described in detail, addressing constrain side effects and rational strategies to establish characteristics of ideal hernia repair meshes. The engineered prosthetics are defined as a transit to the biomimetic smart hernia repair scaffolds with specific advantages and disadvantages, including hydrogel scaffolds, electrospinning membranes, and three-dimensional patches. Lastly, this review critically outlines the future research direction for successful hernia repair solutions by combing state-of-the-art techniques and materials.

A Comparative Study on Outcomes and Quality of Life Changes Following Ventral Transabdominal Preperitoneal (Ventral-TAPP) and Laparoscopic Intraperitoneal Onlay Mesh (IPOM)-Plus Repair for Ventral Hernia

Background Ventral transabdominal preperitoneal (ventral-TAPP) repair and intraperitoneal onlay mesh (IPOM) plus repair are two options among the available techniques of laparoscopic ventral hernia repair (LVHR). We conducted a comparative study to evaluate the clinical and quality of life (QoL)-related outcomes between ventral-TAPP and IPOM-plus repair. It was hypothesized that both procedures offered similar outcomes and QoL. Materials and methods The study included 32 consecutive patients undergoing LVHR, divided equally between ventral-TAPP and IPOM-plus groups. In the ventral-TAPP procedure, a peritoneal flap was created around the defect, followed by defect approximation and polypropylene mesh placement in the pre-peritoneal pocket. For the IPOM-plus procedure, the defect was closed and a composite (dual-side) mesh was placed around the defect. The minimum overlap beyond the original defect margin in both groups was 5 cm. Data regarding pre-operative parameters and postoperative outcomes, including pain and QoL at one week, one month, and three months, were recorded. A p-value of less than or equal to 0.05 was considered to be statistically significant. Results While the mean duration of surgery was longer, the cost of treatment was lower in group 1 (ventral-TAPP) with a p-value of <0.05 for both parameters. The length of hospital stay was significantly shorter in group 1 (ventral-TAPP), while the return to normal activity was similar in both groups. The visual analog scale (VAS) score for overall pain perception and the European registry for abdominal wall hernias (EuraHS; hernia-related QoL) score for 'Pain at Site' and 'Restriction of Activity' domains were significantly higher in group 2 (IPOM-plus) at one week. Conclusion Although the ventral-TAPP procedure requires more time and expertise to perform, the EuraHS QoL assessment at one week was better in group 1 (ventral-TAPP). Ventral-TAPP group scored better in terms of length of hospital stay and cost-effectiveness as well.

Incidence, risk factors, and burden of incisional hernia repair after abdominal surgery in France: a nationwide study

PURPOSE

Incisional hernias are common after laparotomies. The aims of this study were to assess the rate of incisional hernia repair after abdominal surgery, recurrence rate, hospital costs, and risk factors, in France.

METHODS

This national, retrospective, longitudinal, observational study was based on the exhaustive hospital discharge database (PMSI). All adult patients (≥ 18 years old) hospitalised for an abdominal surgical procedure between 01-01-2013 and 31-12-2014 and hospitalised for incisional hernia repair within five years were included. Descriptive analyses and cost analyses from the National Health Insurance (NHI) viewpoint (hospital care for the hernia repair) were performed. To identify risk factors for hernia repair a multivariable Cox model and a machine learning analysis were performed.

RESULTS

In 2013-2014, 710074 patients underwent abdominal surgery, of which 32633 (4.6%) and 5117 (0.7%) had ≥ 1 and ≥ 2 incisional hernia repair(s) within five years, respectively. Mean hospital costs amounted to €4153/hernia repair, representing nearly €67.7 million/year. Some surgical sites exposed patients at high risk of incisional hernia repair: colon and rectum (hazard ratio [HR] 1.2), and other sites on the small bowel and the peritoneum (HR 1.4). Laparotomy procedure and being ≥ 40 years old put patients at high risk of incisional hernia repair even when operated on low-risk sites such as stomach, duodenum, and hepatobiliary.

CONCLUSION

The burden of incisional hernia repair is high and most patients are at risk either due to age ≥ 40 or the surgery site. New approaches to prevent the onset of incisional hernia are warranted.

What is the ideal mesh location for incisional hernia prevention during elective laparotomy? A network meta-analysis of randomized trials

BACKGROUND

Incisional hernia (IH) represents an important complication after surgery. Prophylactic mesh reinforcement (PMR) with different mesh locations [onlay (OL), retromuscular (RM), preperitoneal (PP), and intraperitoneal (IP)] has been described to possibly reduce the risk of postoperative IH. However, data reporting the 'ideal' mesh location are sparse. The aim of this study was to evaluate the optimal mesh location for IH prevention during elective laparotomy.

METHODS

Systematic review and network meta-analysis of randomized controlled trials (RCTs). OL, RM, PP, IP, and no mesh (NM) were compared. The primary aim was postoperative IH. Risk ratio (RR) and weighted mean difference (WMD) were used as pooled effect size measures, whereas 95% credible intervals (CrI) were used to assess relative inference.

RESULTS

Fourteen RCTs (2332 patients) were included. Overall, 1052 (45.1%) had no mesh (NM) while 1280 (54.9%) underwent PMR stratified in IP ( n =344 pts), PP ( n =52 pts), RM ( n =463 pts), and OL ( n =421 pts) placement. Follow-up ranged from 12 months to 67 months. RM (RR=0.34; 95% CrI: 0.10-0.81) and OL (RR=0.15; 95% CrI: 0.044-0.35) were associated with significantly reduced IH RR compared to NM. A tendency toward reduced IH RR was noticed for PP versus NM (RR=0.16; 95% CrI: 0.018-1.01), while no differences were found for IP versus NM (RR=0.59; 95% CrI: 0.19-1.81). Seroma, hematoma, surgical site infection, 90-day mortality, operative time and hospital length of stay were comparable among treatments.

CONCLUSIONS

RM or OL mesh placement seems associated with reduced IH RR compared to NM. PP location appears promising; however, future studies are warranted to corroborate this preliminary indication.

Motion lubrication suppressed mechanical activation via hydrated fibrous gene patch for tendon healing

Mechanical activation of fibroblasts, caused by friction and transforming growth factor-β1 recognition, is one of the main causes of tissue adhesions. In this study, we developed a lubricated gene-hydrogel patch, which provides both a motion lubrication microenvironment and gene therapy. The patch's outer layer is composed of polyethylene glycol polyester hydrogel. The hydrogel forms hydrogen bonds with water molecules to create the motion lubrication layer, and it also serves as a gene delivery library for long-term gene silencing. Under the motion lubricated microenvironment, extracellular signal-regulated kinase-small interfering RNA can silence fibroblasts and enhance the blocking effect against fibroblast activation. In vitro, the proposed patch effectively inhibits fibroblast activation and reduces the coefficient of friction. In vivo, this patch reduces the expression of vimentin and α-smooth muscle actin in fibroblasts. Therefore, the lubricated gene-hydrogel patch can inhibit the mechanical activation of fibroblasts to promote tendon healing.

Prophylactic effect of retromuscular mesh placement during loop ileostomy closure on incisional hernia incidence-a multicentre randomised patient- and observer-blind trial (P.E.L.I.O.N trial)

BACKGROUND

Incisional hernia is a frequent complication following loop ileostomy reversal. Incisional hernias are associated with morbidity, loss of health-related quality of life and costs and warrant the investigation of prophylactic measures. Prophylactic mesh implantation at the time of surgical stoma reversal has shown to be a promising and safe method to prevent incisional hernias in this setting. However, the efficacy of this method has not yet been investigated in a large multicentre randomised-controlled trial (RCT) with adequate external validity. The P.E.L.I.O.N. trial will evaluate the efficacy of prophylactic mesh reinforcement after loop ileostomy closure in decreasing the rate of incisional hernia versus standard closure alone.

METHODS

P.E.L.I.O.N. is a multicentre, patient- and observer-blind RCT. Patients undergoing loop ileostomy closure will undergo intraoperative 1:1 randomisation into either abdominal wall closure with a continuous slowly absorbable suture in small-stitch technique without mesh reinforcement (control group) or abdominal wall closure with an additional reinforcement with a retromuscular non-absorbable, macro-pore (pore size ≥ 1000 μm or effective porosity >0%) light-weight monofilament or mixed structure mesh. A total of 304 patients (152 per group) will need to be randomised in the study. Based on inclusion and exclusion criteria, 1,014 patients are expected to be screened for eligibility in order to recruit the necessary number of patients. The primary endpoint will be the frequency of incision hernias within 24 months according to the European Hernia Society definition. Secondary endpoints will be the frequency of surgical site occurrences (including surgical site infections, wound seromas and hematomas, and enterocutaneous fistulas), postoperative pain, the number of revision surgeries and health-related quality of life. Safety will be assessed by measuring postoperative complications ≥ grade 3 according to the Dindo-Clavien classification.

DISCUSSION

Depending on the results of the P.E.L.I.O.N. trial, prophylactic mesh implantation could become the new standard for loop ileostomy reversal.

TRIAL REGISTRATION

DRKS00027921, U1111-1273-4657.

Incisional hernia prevention: risk-benefit from a patient perspective (INVITE) - protocol for a single-centre, mixed-methods, cross-sectional study aiming to determine if using prophylactic mesh in incisional hernia prevention is acceptable to patients

INTRODUCTION

Incisional hernia (IH) is a common complication of abdominal surgery affecting between 10% and 20% of patients and is associated with significant morbidity along with cost to the National Health Service. With high recurrence rates following repair, focus must be on prevention of IH rather than cure. There is an increasing evidence that patients at high risk of developing IH may benefit from prophylactic mesh placement during their index operation. With recent controversy surrounding the use of mesh in the UK, however, there is little understanding of whether this intervention would be acceptable to patients.

METHODS AND ANALYSIS

INVITE is a mixed-methods, cross-sectional study to explore patient perceptions of the use of mesh as prophylaxis to prevent IH. Patients with and without IH who have undergone colorectal surgery between 2017 and 2020 in a single UK health-board will be approached to participate. 120 participants will be asked to complete a questionnaire and a subgroup of 24 participants will be invited to semistructured interviews. The primary outcome is to assess the acceptability of prophylactic mesh to patients. Secondary outcomes include understanding patients' knowledge of IH, and factors that may influence or alter the acceptability of mesh. Questionnaires have been developed using a 5-point Likert scale to allow quantitative analysis. Qualitative analysis of interviews will be conducted using NVivo software and thematic analysis. Data will be presented using the Journal Article Reporting Standards for mixed-methods research.

ETHICS AND DISSEMINATION

Ethical approval has been granted by REC Wales (22/PR/0678), and the study is currently in setup. All participants will be required to provide informed consent prior to their participation in the study. We plan to report the results of the study in peer-reviewed scientific and medical journals and via presentations at scientific meetings. Results from this study will aid the design of interventional trials using prophylactic mesh.

TRIAL REGISTRATION NUMBER

NCT05384600.

Don't fear the (small) bite: A narrative review of the rationale and misconceptions surrounding closure of abdominal wall incisions

Background

The most common complications related to the closure of abdominal wall incisions are surgical site infections, wound dehiscence and the development of an incisional hernia. Several factors relating to the surgical technique and the materials used have been identified and analysed over the years, as mirrored in the current recommendations of the European Hernia Society, but some misconceptions still remain that hinder wide implementation.

Method

A literature search was performed in the PubMed and GoogleScholar databases on 15 July 2021 and additionally on 30 March 2022 to include recent updates. The goal was to describe the scientific background behind the optimal strategies for reducing incisional hernia risk after closure of abdominal wall incisions in a narrative style review.

Results

An aponeurosis alone, small bites/small steps continuous suture technique should be used, using a slowly resorbable USP 2/0 or alternatively USP 0 suture loaded in a small ½ circle needle. The fascial edges should be properly visualised and tension should be moderate.

Conclusion

Despite the reproducibility, low risk and effectiveness in reducing wound complications following abdominal wall incisions, utilisation of the recommendation of the guidelines of the European Hernia Society remain relatively limited. More work is needed to clear misconceptions and disseminate the established knowledge and technique especially to younger surgeons.

Updated guideline for closure of abdominal wall incisions from the European and American Hernia Societies

BACKGROUND

Incisional hernia is a frequent complication of abdominal wall incision. Surgical technique is an important risk factor for the development of incisional hernia. The aim of these updated guidelines was to provide recommendations to decrease the incidence of incisional hernia.

METHODS

A systematic literature search of MEDLINE, Embase, and Cochrane CENTRAL was performed on 22 January 2022. The Scottish Intercollegiate Guidelines Network instrument was used to evaluate systematic reviews and meta-analyses, RCTs, and cohort studies. The GRADE approach (Grading of Recommendations, Assessment, Development and Evaluation) was used to appraise the certainty of the evidence. The guidelines group consisted of surgical specialists, a biomedical information specialist, certified guideline methodologist, and patient representative.

RESULTS

Thirty-nine papers were included covering seven key questions, and weak recommendations were made for all of these. Laparoscopic surgery and non-midline incisions are suggested to be preferred when safe and feasible. In laparoscopic surgery, suturing the fascial defect of trocar sites of 10 mm and larger is advised, especially after single-incision laparoscopic surgery and at the umbilicus. For closure of an elective midline laparotomy, a continuous small-bites suturing technique with a slowly absorbable suture is suggested. Prophylactic mesh augmentation after elective midline laparotomy can be considered to reduce the risk of incisional hernia; a permanent synthetic mesh in either the onlay or retromuscular position is advised.

CONCLUSION

These updated guidelines may help surgeons in selecting the optimal approach and location of abdominal wall incisions.

Prevention of Incisional Hernias by Prophylactic Mesh-augmented Reinforcement of Midline Laparotomies for Abdominal Aortic Aneurysm Treatment: Five-year Follow-up of a Randomized Controlled Trial

INTRODUCTION

The incidence of incisional hernias (IHs) after open repair of an abdominal aortic aneurysm (AAA) is high. Several randomized controlled trials have reported favorable results with the use of prophylactic mesh to prevent IHs, without increasing complications. In this analysis, we report on the results of the 60-month follow-up of the PRIMAAT trial.

METHODS

In a prospective, multicenter, open-label, randomized design, patients were randomized between prophylactic retrorectus mesh reinforcement (mesh group), and primary closure of their midline laparotomy after open AAA repair (no-mesh group). This article reports on the results of clinical follow-up after 60 months. If performed, ultrasonography or computed tomography were used for the diagnosis of IHs.

RESULTS

Of the 120 randomized patients, 114 were included in the intention-to-treat analysis. Thirty-three patients in the no-mesh group (33/58-56.9%) and 34 patients in the mesh group (34/56-60.7%) were evaluated after 5 years. In each treatment arm, 10 patients died between the 24-month and 60-month follow-up. The cumulative incidence of IHs in the no-mesh group was 32.9% after 24 months and 49.2% after 60 months. No IHs were diagnosed in the mesh group. In the no-mesh group, 21.7% (5/23) underwent reoperation within 5 years due to an IH.

CONCLUSIONS

Prophylactic retrorectus mesh reinforcement after midline laparotomy for the treatment of AAAs safely and effectively decreases the rate of IHs. The cumulative incidence of IHs after open AAA repair, when no mesh is used, continues to increase during the first 5 years after surgery, which leads to a substantial rate of hernia repairs.

Incisional hernia following colorectal cancer surgery according to suture technique: Hughes Abdominal Repair Randomized Trial (HART)

BACKGROUND

Incisional hernias cause morbidity and may require further surgery. HART (Hughes Abdominal Repair Trial) assessed the effect of an alternative suture method on the incidence of incisional hernia following colorectal cancer surgery.

METHODS

A pragmatic multicentre single-blind RCT allocated patients undergoing midline incision for colorectal cancer to either Hughes closure (double far-near-near-far sutures of 1 nylon suture at 2-cm intervals along the fascia combined with conventional mass closure) or the surgeon's standard closure. The primary outcome was the incidence of incisional hernia at 1 year assessed by clinical examination. An intention-to-treat analysis was performed.

RESULTS

Between August 2014 and February 2018, 802 patients were randomized to either Hughes closure (401) or the standard mass closure group (401). At 1 year after surgery, 672 patients (83.7 per cent) were included in the primary outcome analysis; 50 of 339 patients (14.8 per cent) in the Hughes group and 57 of 333 (17.1 per cent) in the standard closure group had incisional hernia (OR 0.84, 95 per cent c.i. 0.55 to 1.27; P = 0.402). At 2 years, 78 patients (28.7 per cent) in the Hughes repair group and 84 (31.8 per cent) in the standard closure group had incisional hernia (OR 0.86, 0.59 to 1.25; P = 0.429). Adverse events were similar in the two groups, apart from the rate of surgical-site infection, which was higher in the Hughes group (13.2 versus 7.7 per cent; OR 1.82, 1.14 to 2.91; P = 0.011).

CONCLUSION

The incidence of incisional hernia after colorectal cancer surgery is high. There was no statistical difference in incidence between Hughes closure and mass closure at 1 or 2 years.

REGISTRATION NUMBER

ISRCTN25616490 (http://www.controlled-trials.com).

Prophylactic mesh reinforcement for midline incisional hernia prevention: systematic review and updated meta-analysis of randomized controlled trials

BACKGROUND

Incisional hernia (IH) is a common complication after abdominal surgery. Prevention of IH is matter of intense research. Prophylactic mesh reinforcement (PMR) has been shown to be promising in the minimization of IH risk after elective midline laparotomy.

METHODS

Systematic review and meta-analysis of randomized controlled trials (RCTs) comparing PMR vs. primary suture closure (PSC). Risk ratio (RR) and standardized mean difference (MD) were used as pooled effect size measures whereas 95% confidence intervals (95%CI) were used to assess relative inference.

RESULTS

Fourteen RCTs (2332 patients) were included. Overall, 1280 (54.9%) underwent PMR while 1052 (45.1%) PSC. Postoperative follow-up ranged from 12 to 67 months. The incidence of IH was reduced for PMR vs. PSC (13.4% vs. 27.5%). The estimated pooled IH RR for PMR vs. PSC is 0.38 (95% CI 0.24-0.58; p < 0.001). Stratified subgroup analysis according to mesh location shows a risk reduction for intraperitoneal (RR = 0.65; 95% CI 0.48-0.89), preperitoneal (RR = 0.18; 95% CI 0.04-0.81), retromuscular (RR = 0.47; 95% CI 0.24-0.92) and onlay (RR = 0.24; 95% CI 0.12-0.51) compared to PSC. The seroma RR was higher for PMR (RR = 2.05; p = 0.0008). No differences were found for hematoma (RR = 1.49; p = 0.34), surgical site infection (SSI) (RR = 1.17; p = 0.38), operative time (OT) (MD = 0.27; p = 0.413), and hospital length of stay (HLOS) (MD = -0.03; p = 0.237).

CONCLUSIONS

PMR seems effective in reducing the risk of IH after elective midline laparotomy compared to PSC in the medium-term follow-up. While the risk of postoperative seroma appears higher for PMR, hematoma, SSI, HLOS and OT seems comparable.

Hughes abdominal closure versus standard mass closure to reduce incisional hernias following surgery for colorectal cancer: the HART RCT

BACKGROUND

Incisional hernias can cause chronic pain and complications and affect quality of life. Surgical repair requires health-care resources and has a significant associated failure rate. A prospective, multicentre, single-blinded randomised controlled trial was conducted to investigate the clinical effectiveness and cost-effectiveness of the Hughes abdominal closure method compared with standard mass closure following surgery for colorectal cancer. The study randomised, in a 1 : 1 ratio, 802 adult patients (aged ≥ 18 years) undergoing surgical resection for colorectal cancer from 28 surgical departments in UK centres.

INTERVENTION

Hughes abdominal closure or standard mass closure.

MAIN OUTCOME MEASURES

The primary outcome was the incidence of incisional hernias at 1 year, as assessed by clinical examination. Within-trial cost-effectiveness and cost-utility analyses over 1 year were conducted from an NHS and a social care perspective. A key secondary outcome was quality of life, and other outcomes included the incidence of incisional hernias as detected by computed tomography scanning.

RESULTS

The incidence of incisional hernia at 1-year clinical examination was 50 (14.8%) in the Hughes abdominal closure arm compared with 57 (17.1%) in the standard mass closure arm (odds ratio 0.84, 95% confidence interval 0.55 to 1.27; p = 0.4). In year 2, the incidence of incisional hernia was 78 (28.7%) in the Hughes abdominal closure arm compared with 84 (31.8%) in the standard mass closure arm (odds ratio 0.86, 95% confidence interval 0.59 to 1.25; p = 0.43). Computed tomography scanning identified a total of 301 incisional hernias across both arms, compared with 100 identified by clinical examination at the 1-year follow-up. Computed tomography scanning missed 16 incisional hernias that were picked up by clinical examination. Hughes abdominal closure was found to be less cost-effective than standard mass closure. The mean incremental cost for patients undergoing Hughes abdominal closure was £616.45 (95% confidence interval -£699.56 to £1932.47; p = 0.3580). Quality of life did not differ significantly between the study arms at any time point.

LIMITATIONS

As this was a pragmatic trial, the control arm allowed surgeon discretion in the approach to standard mass closure, introducing variability in the techniques and equipment used. Intraoperative randomisation may result in a loss of equipoise for some surgeons. Follow-up was limited to 2 years, which may not have been enough time to see a difference in the primary outcome.

CONCLUSIONS

Hughes abdominal closure did not significantly reduce the incidence of incisional hernias detected by clinical examination and was less cost-effective at 1 year than standard mass closure in colorectal cancer patients. Computed tomography scanning may be more effective at identifying incisional hernias than clinical examination, but the clinical benefit of this needs further research.

FUTURE WORK

An extended follow-up using routinely collected NHS data sets aims to report on incisional hernia rates at 2-5 years post surgery to investigate any potential mortality benefit of the closure methods. Furthermore, the proportion of incisional hernias identified by a computed tomography scan (at 1 and 2 years post surgery), but not during clinical examination (occult hernias), proceeding to surgical repair within 3-5 years after the initial operation will be explored.

TRIAL REGISTRATION

This trial is registered as ISRCTN25616490.

FUNDING

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 34. See the NIHR Journals Library website for further project information.

A simplified method to evaluate the loss of domain

PURPOSE

The treatment of giant incisional hernia (IH) with loss of domain (LOD, IHLD) is considerably challenging due to technical difficulties and subsequent post-operative complications. These post-operative risks may be anticipated by calculating the abdominal cavity (AC) volume (ACV) and the IH volume (IHV) on the preoperative CT-scans, using the AC and IH dimensions (Tanaka's method) or using tridimensional volumetry (Sabbagh's method). These techniques are often time-consuming and require specific softwares. The aim of the present study was to develop a simple method to rapidly obtain the LOD-ratio on the preoperative CT-Scan.

METHODS

The CT-scans (n = 89) of patients with IHLD were retrospectively studied. Several ratios were calculated using different parameters of the AC and the IH, including width, height and depth, the areas (axial and sagittal ellipse, as well as freehand sagittal surface areas) and these were compared with the reference methods of Sabbagh et al. and Tanaka et al. RESULTS: The LOD ratios calculated from the two reference methods gave similar results (ICC = 0.82, p < 0.0001). The new "R-ratios" (Reims-ratios) obtained from the IH and AC surface areas measured using the "freehand ROI" tool on sagittal view or roughly evaluated by an ellipse on axial view showed excellent correlation with both reference ratios (all ICC ≥ 0.71, p < 0.0001).

CONCLUSION

The LOD ratio may be quickly obtained by drawing two circles on the pre-operative CT scan ("R ratios") and available on the webpage https://romeo.univ-reims.fr/Rratio/ . This will certainly help surgeons to routinely anticipate the post-operative complications before IHLD repair.

Pre-operative factors associated with short- and long-term outcomes in the patient with inguinal hernia: What does the current evidence say?

Hernia repair is one of the most frequent interventions in surgery worldwide. The approach to abdominal wall and inguinal hernias remains a challenge due to emerging evidence on aspects such as timely diagnosis, use of innovative techniques or post-surgical care. However, pre-operative preparation is also a factor that substantially affects the absolute success rate of this type of condition. Time management between diagnosis and intervention, control of diseases that increase intra-abdominal pressure, weight and nutritional status, are some of the many elements to be considered in this type of patients before surgery. Considering that this condition carries high health care costs, especially in case of recurrence, has a risk of complications and affects the individual's functional capacity, the objective of this review is to synthesize evidence on the role of these factors on the short- and long-term outcome of inguinal hernia management, and to make suggestions on the general approach to this type of patients.

Comparative Effectiveness Analysis of Resorbable Synthetic Onlay and Biologic Intraperitoneal Mesh for Abdominal Wall Reconstruction: A 2-Year Match-Paired Analysis

BACKGROUND

Abdominal wall reconstruction persists as a challenging surgical issue with a multitude of management strategies available. The aim of this study was to examine the efficacy of resorbable synthetic mesh onlay plane against biologic mesh in the intraperitoneal plane.

METHODS

A single-center, two-surgeon, 5-year retrospective review (2014 to 2019) was performed examining subjects who underwent abdominal wall reconstruction in the onlay plane with resorbable synthetic mesh or in the intraperitoneal plane with biologic mesh. A matched paired analysis was conducted. Data examining demographic characteristics, intraoperative variables, postoperative outcomes, and costs were analyzed.

RESULTS

Eighty-eight subjects (44 per group) were identified (median follow-up, 24.5 months). The mean age was 57.7 years, with a mean body mass index of 30.4 kg/m2. The average defect size was 292 ± 237 cm2, with most wounds being clean-contaminated (48.9 percent) and 55 percent having failed prior repair. Resorbable synthetic mesh onlay subjects were significantly less likely (4.5 percent) to experience recurrence compared to biologic intraperitoneal mesh subjects (22.7 percent; p < 0.026). In addition, mesh onlay suffered fewer postoperative surgical-site occurrences (18.2 percent versus 40.9 percent; p < 0.019) and required fewer procedural interventions (11.4 percent versus 36.4 percent; p < 0.011), and was also associated with significantly lower total costs ($16,658 ± $14,930) compared to biologic intraperitoneal mesh ($27,645 ± $16,864; p < 0.001).

CONCLUSIONS

Abdominal wall reconstruction remains an evolving field, with various techniques available for treatment. When faced with hernia repair, resorbable synthetic mesh in the onlay plane may be preferable to biologic mesh placed in the intraperitoneal plane because of lower long-term recurrence rates, surgical-site complications, and costs.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Peritoneum-Inspired Janus Porous Hydrogel with Anti-Deformation, Anti-Adhesion, and Pro-Healing Characteristics for Abdominal Wall Defect Treatment

Implantable meshes used in tension-free repair operations facilitate treatment of internal soft-tissue defects. However, clinical meshes fail to achieve anti-deformation, anti-adhesion, and pro-healing properties simultaneously, leading to undesirable surgery outcomes. Herein, inspired by the peritoneum, a novel biocompatible Janus porous poly(vinyl alcohol) hydrogel (JPVA hydrogel) is developed to achieve efficient repair of internal soft-tissue defects by a facile yet efficient strategy based on top-down solvent exchange. The densely porous and smooth bottom-surface of JPVA hydrogel minimizes adhesion of fibroblasts and does not trigger any visceral adhesion, and its loose extracellular-matrix-like porous and rough top-surface can significantly improve fibroblast adhesion and tissue growth, leading to superior abdominal wall defect treatment to commercially available PP and PCO meshes. With unique anti-swelling property (maximum swelling ratio: 6.4%), JPVA hydrogel has long-lasting anti-deformation performance and maintains high mechanical strength after immersion in phosphate-buffered saline (PBS) for 14 days, enabling tolerance to the maximum abdominal pressure in an internal wet environment. By integrating visceral anti-adhesion and defect pro-healing with anti-deformation, the JPVA hydrogel patch shows great prospects for efficient internal soft-tissue defect repair.

OUP accepted manuscript

Background

Despite the fact that emergency midline laparotomy is a risk factor for an incisional hernia, active research on hernia prevention in emergency settings is lacking. Different kinds of meshes and mesh positions have been studied in elective abdominal surgery, but no randomized controlled trials in emergency settings have been published thus far.

Method

The PREEMER trial (registration number NCT04311788) is a multicentre, patient- and assessor-blinded, randomized controlled trial to be conducted in six hospitals in Finland. A total of 244 patients will be randomized at a 1 : 1 ratio to either the retrorectus mesh group, featuring a self-gripping prophylactic mesh, or to the no mesh (control) group, both closed by small-stitch 4 : 1 closure with continuous slowly absorbable monofilament suturing. The primary outcome of the PREEMER trial is the incidence of incisional hernia 2 years after surgery, which will be detected clinically and/or radiologically. Secondary outcomes are the Comprehensive Complication Index score, incidence of surgical-site infections and fascial dehiscence within 30 days of surgery; the incisional hernia repair rate and mesh- or hernia-related reoperations within the 2- and 5-year follow-ups; the incidence of incisional hernia within the 5-year follow-up; and quality of life measured by RAND-36, the Activities Assessment Scale and the PROMIS questionnaire within 30 days and 2 and 5 years from surgery. Additionally, health–economic explorative measures will be explored.

Conclusion

The PREEMER trial will provide level 1 evidence on incisional hernia prevention in an emergency setting.

Registration number

NCT04311788 (http://www.clinicaltrials.gov). Registered 7 March 2020.

Fascial Dehiscence and Incisional Hernia Prediction Models: A Systematic Review and Meta-analysis

BACKGROUND

Fascial dehiscence (FD) and incisional hernia (IH) pose considerable risks to patients who undergo abdominal surgery, and many preventive strategies have been applied to reduce this risk. An accurate predictive model could aid identification of high-risk patients, who could be targeted for particular care. This study aims to systematically review existing FD and IH prediction models.

METHODS

Prediction models were identified using pre-specified search terms on SCOPUS, PubMed, and Web of Science. Eligible studies included those conducted in adult patients who underwent any kind of abdominal surgery, and reported model performance. Data from the eligible studies were extracted, and the risk of bias (RoB) was assessed using the PROBAST tool. Pooling of C-statistics was performed using a random-effect meta-analysis. [Registration: PROSPERO (CRD42021282463)].

RESULTS

Twelve studies were eligible for review; five were FD prediction model studies. Most included studies had high RoB, especially in the analysis domain. The C-statistics of the FD and IH prediction models ranged from 0.69 to 0.92, but most have yet to be externally validated. Pooled C-statistics (95% CI) were 0.80 (0.74, 0.86) and 0.81 (0.75, 0.86) for the FD (external-validation) and IH prediction model, respectively. Some predictive factors such as body mass index, smoking, emergency operation, and surgical site infection were associated with FD or IH occurrence and were included in multiple models.

CONCLUSIONS

Several models have been developed as an aid for FD and IH prediction, mostly with modest performance and lacking independent validation. New models for specific patient groups may offer clinical utility.

PROphylactic MESH (PROMESH) for stoma closure: does it reduce the incidence of incisional hernia? Protocol for a triple-blinded randomised controlled trial

INTRODUCTION

Application of a prophylactic mesh during stoma closure was shown to reduce the incidence of incisional hernia at the site of stoma closure. Our objective is to provide high quality evidence to validate this finding.

METHODS AND ANALYSIS

The study will be a randomised controlled triple-blinded superiority parallel monocentric trial. Patients undergoing elective ileostomy or colostomy closure after surgery for digestive cancer will be eligible for inclusion. Patients allergic to the mesh, immunosuppressed or refusing to participate will be excluded. Randomisation will be performed based on a 1:1 allocation ratio between stoma closure with application of a non-absorbable mesh in the sublay position (intervention) and stoma closure without a mesh (control). The primary outcome will be the 1-year incidence of incisional hernia at the site of stoma closure, determined clinically and by CT. Secondary outcomes will be the 31-day incidence of surgical site infection and the modified Carolinas Comfort Scale. Patients, radiologists and investigators performing the assessment at 1 year will be blinded for the allocated study group. Analysis will be performed in intention-to-treat. The trial will include 68 patients (34 with mesh, 34 without mesh).

ETHICS AND DISSEMINATION

The present randomised controlled trial was registered into clinicaltrials.gov (NCT04510558) and was accepted by the local ethic committee (Geneva, Switzerland: CCER 2021-00053). The results will be presented at national and international congresses in the fields of colorectal surgery and general surgery, and published in a peer-reviewed journal.

Examination of lipid profiles in abdominal fascial healing using MALDI-TOF to identify potential therapeutic targets

•

Lipids change overtime in normal fascial healing in the early post-surgery period.

•

Specific lipid species are correlated with the changes of inflammation cells and fibroblasts.

•

Lipid species in the present study are considered as predictive markers for the formation of incisional hernia.

Background

Failure of fascial healing in the abdominal wall can result in incisional hernia, which is one of the most common complications after laparotomy. Understanding the molecular healing process of abdominal fascia may provide lipid markers of incisional hernia or therapeutic targets that allow prevention or treatment of incisional hernias.

Purpose

This study aims to investigate temporal and in situ changes of lipids during the normal healing process of abdominal fascia in the first postoperative week.

Methods

Open hemicolectomy was performed in a total of 35 Wistar rats. The midline fascia was closed identically for all rats using a single continuous suturing technique. These animals were sacrificed with equal numbers (n = 5) at each of 7-time points (6, 12, 24, 48, 72, 120, and 168 h. The local and temporal changes of lipids were examined with mass spectrometry imaging and correlated to histologically scored changes during healing using hematoxylin and eosin staining.

Results

Two phosphatidylcholine lipid species (PC O-38:5 and PC 38:4) and one phosphatidylethanolamine lipid (PE O-16:1_20:4) were found to significantly correlate with temporal changes of inflammation. A phosphatidylcholine (PC 32:0) and a monosialodihexosylganglioside (GM3 34:1;2) were found to correlate with fibroblast cell growth.

Conclusion

Glycerophospholipids and gangliosides are strongly involved in the normal healing process of abdominal fascia and their locally fluctuating concentrations are considered as potential lipid markers and therapeutic targets of fascial healing.

When to use a prophylactic mesh after stoma closure: a case-control study

Purpose

The closure of a stoma is frequently associated with an acceptable morbidity and mortality. One of the most frequent complications is incisional hernia at the stoma site, which occurs in 20%–40% of cases, higher than incisions in other parts of the abdomen. The objective of this study was to identify the risk factors associated with the presentation of incisional hernia after stoma closure, this in order to select patients who are candidates for prophylactic mesh placement during closure.

Methods

An unpaired case–control study was conducted. This study involved 164 patients who underwent a stoma closure between January 2014 and December 2019. Associated factors for the development of incisional hernia at the site of the stoma after closure were identified, for which it was performed a logistic regression analysis.

Results

41 cases and 123 controls were analyzed, with a mean follow-up of 35.21 ± 18.42 months, the mean age for performing the stoma closure was 65.28 ± 14.07 years, the most frequent cause for performing the stoma was malignant disease (65.85%). Risk factor for the development of incisional hernia at the stoma site after its closure was identified as a history of parastomal hernia (OR 5.90, CI95% 1.97–17.68).

Conclusions

The use of prophylactic mesh at stoma closure should be considered in patients with a history of parastomal hernia since these patients present a significantly higher risk of developing a hernia.

Factors affecting return to work after surgical treatment of trapeziometacarpal joint osteoarthritis

This study aimed to identify factors contributing to the timing of return to work after surgical treatment of trapeziometacarpal joint osteoarthritis and to calculate the costs of lost productivity. We included 627 patients with paid employment who underwent trapeziectomy and ligament reconstruction with tendon interposition. Time to return to work was measured through filling online questionnaires and analysed using survival analysis at 6 weeks and 3, 6 and 12 months after the surgery. Patients also filled in the Michigan Hand Outcomes Questionnaire. Costs of lost productivity were calculated using the human capital method. After 1 year, 78% of the patients returned to work. The median time to return to work was 12 weeks. Factors that significantly affected the time to return to work were occupational intensity (light, moderate or heavy physical labour), whether the dominant hand was treated and the Michigan Hand Outcomes Questionnaire work score and hand function score of the unoperated side at baseline. The costs of lost productivity were estimated at €11,000 on the patient level, resulting in €16.8 million on the Dutch population level per year.Level of evidence: II.

High rate of incisional hernia observed after mass closure of burst abdomen

PURPOSE

This study investigated the long-term development of incisional hernia after implementation of a standardized surgical treatment strategy for burst abdomen in abdominal midline incisions with a continuous mass closure technique.

METHODS

The study was a single-center, observational study evaluating all patients treated for burst abdomen between June 2014 and April 2019 with a long-term follow-up in October 2020. In June 2014, a standardized surgical treatment for burst abdomen involving a monofilament, slowly absorbable suture in a continuous mass-closure stitch with large bites of 3 cm and small steps of 5 mm was introduced. The occurrence of incisional hernia was investigated and defined as a radiological-, clinical-, or intraoperative finding of a hernia in the abdominal midline incision at follow-up.

RESULTS

Ninety-four patients suffered from burst abdomen during the study period. Eighty patients were eligible for follow-up. The index surgery prior to burst abdomen was an emergency laparotomy in 78% (62/80) of the patients. Nineteen patients died within the first 30 postoperative days and 61 patients were available for further analysis. The long-term incisional hernia rate was 33% (20/61) with a median follow-up of 17 months (min 4, max 67 months).

CONCLUSION

Standardized surgery for burst abdomen with a mass-closure technique using slow absorbable running suture results in high rates of long-term incisional hernias, comparable to the hernia rates reported in the literature among this group of patients.

Shear wave elastography biases in abdominal wall layers characterization

Ventral incisional hernia repair is one of the most common surgical procedures. The characterization of the abdominal wall layer mechanical properties is the first step towards personalized treatment. This study investigates the capability of elastography to assess these properties using anin vivoandin vitromodel of abdominal wall layers. Two experiment approaches are considered: shear wave elastography imaging and guided wave dispersion characterization, where the latter is used as a reference. Results show measurement biases in the shear wave elastography approach in such a layer structure configuration. Methods to overcome these biases are suggested to improve and to correct the elastography approach for abdominal wall layers and similar anatomical structures.

Does the Choice of Extraction Site During Minimally Invasive Colorectal Surgery Change the Incidence of Incisional Hernia? Protocol for a Systematic Review and Network Meta-Analysis

Background

Various sites are used for specimen extraction in oncological minimally invasive colorectal surgery. The objective is to determine if the choice of extraction site modulates the incidence of incisional hernia (IH).

Methods/design

A systematic review will be performed in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. MEDLINE, Embase and CENTRAL will be searched to look for original studies reporting the incidence of IH after minimally invasive colorectal surgery. Studies will be excluded from the analysis if: 1) they do not report original data, 2) the outcome of interest (incidence of incisional hernia) is not clearly reported and does not allow to extrapolate and/or calculate the required data for network meta-analysis, 3) they include pediatric patients, 4) they include a patients' population with a conversion rate to laparotomy >10%, 5) they do not compare at least two different extraction sites for the operative specimen, 6) they report patients who underwent pure (and not hybrid) natural orifice transluminal endoscopic surgery (NOTES). Network meta-analysis will be performed to determine the incidence of IH per extraction site.

Discussion

By determining which specimen extraction site leads to reduced rate of IH, this systematic review and network meta-analysis will help colorectal surgeons to choose their extraction site and reduce the morbidity and costs associated with IH.

Registration

The systematic review and meta-analysis protocol is registered in the International Prospective Register of Ongoing Systematic Reviews (PROSPERO) with number CRD42021272226.

Highlights

Various sites are used for specimen extraction in oncological minimally invasive colorectal surgery, and the choice of the site may probably modulate the incidence of incisional hernia.The present protocol aims to design a systematic review which will identify original studies comparing two extraction sites during minimally invasive colorectal surgery in terms of incidence of incisional hernia.Network meta-analysis will be performed to determine the incidence of IH per extraction site.

Midline incisional hernia prophylaxis using synthetic mesh in an emergency or urgent gastrointestinal tract surgery: a protocol for multicentre randomised clinical trial

INTRODUCTION

Between 5% and 30% of abdominal incisions eventually result in incisional hernias (IHs) that can lead to severe complications and impaired quality of life. Unfortunately, IH repair is often unsuccessful; therefore, hernia prophylaxis is an important issue. The efficacy of mesh augmentation has been proven for hernia prophylaxis in high-risk patients, but no randomised clinical trial has evaluated prophylactic mesh placement in emergency/urgent gastrointestinal operations.

METHODS AND ANALYSIS

A multicentre, prospective randomised, open and patient-assessor blinded endpoint design will be conducted. A total of 470 patients will be enrolled and randomly allocated to retrorectus mesh augmentation with lightweight polypropylene mesh or primary suture closure. The primary outcome is IH occurrence within 24 months of follow-up, while other clinical outcomes are secondary endpoints. A cost-effectiveness analysis will be conducted from the societal and provider perspectives.

ETHICS AND DISSEMINATION

Ethics approval was obtained from Ramathibodi Hospital (MURA2020/1478) and Vajira Hospital (COA164/2563). The protocol is on the process of submission to the local ethics committee of the other study sites. Results will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

TCTR20200924002.

Risk-benefit assessment of onlay and retrorectus mesh augmentation for incisional hernia prophylaxis: A secondary analysis from network meta-analysis

BACKGROUND

Mesh augmentation has proved efficacious for the prevention of incisional hernia (IH). A recent network meta-analysis (NMA) identified onlay and retrorectus mesh (OM and RM) as the most effective therapeutic options, but the risk of surgical site infection (SSI) and other complications require additional consideration.

METHODS

The NMA generated pooled risk differences (RD) for the benefits of reducing IH and the risk of SSI and composite seroma/hematoma (CSH) for use in Monte-Carlo data simulations with 1000 replications. Mean incremental risk-benefit ratios (IRBR), i.e., the ratio of incremental risk (or RD) and incremental benefit, and 95% confidence intervals (95% CI) were estimated with a probability of risk-benefits (PRB) across risk-benefit acceptability thresholds from the acceptability curves generated.

RESULTS

The RDs of IH were 0.237 and 0.201 lower in OM and RM than primary suture closure, compared to 0.027 and -0.001 for SSI. IRBRs (95% CI) for SSI risk were -0.118 (-0.124, -0.112) and 0.006 (-0.002, 0.013) for OM and RM, respectively. PRBs were much higher in RM than OM, especially at low acceptability thresholds of 0.05 and 0.1. IRBRs (95% CI) for CSH were -0.388 (-0.395, -0.381) and -0.105 (-0.111, -0.100) for OM and RM, respectively. RM yielded a PRB of 0.87 at an acceptability threshold of 0.2, in contrast to OM, which did not.

CONCLUSION

Overall, RM offered improved benefit in IH prophylaxis over the risk of complications relative to OM and appeared to be the preferred treatment option for this indication.