A comparative study of sutured versus bovine pericardium mesh abdominal closure after open abdominal aortic aneurysm repair

The MESH-RTL Project for prevention of abdominal wound dehiscence (AWD) in high-risk patients: noninferiority, randomized controlled trial

PURPOSE

To compare reinforced tension line (RTL) and mesh techniques in the onlay position for preventing abdominal wound dehiscence (AWD) in a noninferiority clinical trial.

METHODS

Patients > 18 years old who underwent midline laparotomy and who were considered at high risk on the modified Rotterdam risk scale were included. The outcomes analyzed were the incidence of AWD and surgical site occurrence (SSO).

RESULTS

239 patients were included: 121 mesh group and 118 RTL group. Five (4.1%) of the 121 patients in the mesh group and 7 (5.9%) of the 118 patients in the RTL group presented with AWD (p = 0.56, RR = 0.69, 95% CI = 0.22-2.13) in the per-protocol analysis. The median time of presentation was 6 days. The 95% CI (-0.0567, 0.0231) for the difference in incidence between the two groups was entirely within the predefined noninferiority margin of 5%. The incidence of complications did not significantly differ between the two groups: the mesh group (27, 22.3%) and the RTL group (16, 12.8%) (p = 0.09, RR (95% CI) = 1.64 (0.93-2.89)).

CONCLUSION

The use of the RTL technique for preventing AWD was not inferior to the use of mesh in the onlay position, nor did it increase the risk of complications. This study was registered on clinicaltrials.gov: Mesh-RTL Project (NCT04134455).

Prophylactic Mesh Reinforcement Versus Primary Suture for Abdominal Wall Closure after Elective Abdominal Aortic Aneurysm Repair with Midline Laparotomy Incision: Updated Systematic Review Including Time-To-Event Meta-Analysis and Trial Sequential Analysis of Randomized Controlled Trials

BACKGROUND

Patients undergoing open abdominal aortic aneurysm (AAA) repair have a high risk of incisional hernia. Heterogeneity in recommendations regarding prophylactic mesh reinforcement between scientific society guidelines reflects the lack of sufficient data, with the Society for Vascular Surgery making no recommendation on methods for abdominal wall closure. We aimed to synthesize the most current evidence on mesh versus primary suture abdominal wall closure after open AAA repair.

METHODS

A systematic review was conducted on randomized controlled trials (RCTs) comparing mesh reinforcement with primary abdominal wall closure for patients who underwent elective AAA repair with a midline laparotomy incision. Dichotomous and time-to-event data were pooled using random effects models, applying the Mantel-Haenszel or inverse variance statistical method. The revised Cochrane tool and Grades of Recommendation, Assessment, Development, and Evaluation framework were used to assess the risk of bias and certainty of evidence, respectively. Trial sequential analysis assumed alpha = 5% and power = 80%.

RESULTS

Five RCTs were included reporting a total of 487 patients (260 in the mesh group and 227 in the primary suture group). Patients who had mesh closure had statistically significantly lower odds of developing incisional hernia after open AAA repair than those with primary suture closure (odds ratio (OR) 0.20, 95% confidence interval (CI) 0.09-0.43). Time-to-event analysis confirmed that the hazard of incisional hernia was statistically significantly lower in patients who had mesh closure (P < 0.05). Meta-analysis found statistically significantly lower odds of reoperation for incisional hernia in the mesh group (OR 0.23, 95% CI 0.06-0.93), but there was no statistically significant difference in wound infection (risk difference 0.02, 95% CI -0.03-0.08). The overall risk of bias was low in one study, high in 2 studies, "some concerns" in 2 studies for incisional hernia and reoperation for incisional hernia, and high in all studies reporting wound infection. The certainty of evidence was judged to be low for all outcomes. Trial sequential analysis confirmed a benefit of mesh reinforcement in reducing the risk of incisional hernia.

CONCLUSIONS

Meta-analysis of the highest-level data demonstrated a benefit of prophylactic mesh reinforcement, with trial sequential analysis confirming no additional RCTs required. This provides compelling evidence to support the use of mesh for midline laparotomy closure in patients undergoing open AAA repair.

Evaluation of Mesh Closure of Laparotomy and Extraction Incisions in Open and Laparoscopic Colorectal Surgery: A Systematic Review and Meta-Analysis

Background and Objectives: Evisceration and incisional hernia (IH) represent a significant morbidity following open or laparoscopic colorectal surgery where midline laparotomy or extraction incision (EI) are performed. We executed a systematic review to evaluate primary mesh closure of laparotomy or EI in colorectal resections of benign or malignant conditions. Methods: A comprehensive literature search was performed using PubMed, Science Direct, Cochrane, and Google Scholar databases for studies comparing prophylactic mesh to traditional suture techniques in closing laparotomy in open approach or EI when minimally invasive surgery was adopted in colorectal procedures, regardless of the diagnosis. Both IH and evisceration were identified as primary outcomes. Secondary outcomes included surgical site infections (SSI), postoperative seroma, and length of hospital stay (LOS). Results: Six studies were included in our analysis with a total population of 1398 patients, of whom 411 patients had prophylactic mesh augmentation when closing laparotomy or EI, and 987 underwent suture closure. The mesh closure group had a significantly lower risk of developing IH compared to the conventional closure group (OR 0.23, p = 0.00001). This result was significantly consistent in subgroup analysis of open laparotomy or EI of laparoscopic surgery subgroups. There was no statistically notable difference in evisceration incidence (OR 0.51, p = 0.25). Secondary endpoints did not significantly differ between both groups in terms of SSI (OR 1.20, p = 0.54), postoperative seroma (OR 1.80, p = 0.13), and LOS (MD -0.54, p = 0.63). Conclusions: primary mesh reinforcement of laparotomy or EI closure in colorectal resections lessens IH occurrence. No safety concerns were identified; however, further high-quality research may provide more solid conclusions.

Prophylactic slowly resorbable mesh in midline laparotomy to limit incisional hernia incidence: the prospective 'Mesh Augmented Reinforcement of Abdominal Wall Suture Line (MARS)' cohort study protocol

Background

Incisional hernia (IH) after abdominal surgery is a frequent surgical complication. Risk factors associated with IH are midline incisions, patients with an abdominal aneurysm of the aorta, and high BMI. Preventive measures include the use of the small-bites suture technique and/or placing a prophylactic mesh for reinforcement of the midline closure. Although recommended for high-risk patients, many surgeons are still reluctant to place a prophylactic mesh due to related complications. To counter these concerns, new synthetic resorbable meshes are being developed, such as the Deternia Self-Gripping Resorbable Mesh ("investigational device"). However, the effectiveness of this mesh in IH prevention has not been proved.

Methods

The Mesh Augmented Reinforcement of Abdominal Wall Suture Line (MARS) study is a European, multicentre, prospective, single-arm study. A total of 120 patients scheduled for elective midline laparotomy, and for that reason at risk of developing IH, will be recruited in ~12 sites after informed consent. The sample size was estimated based on greater than 80% power, two-sided alpha of 0.05, an expected 12 month IH rate of 8% and a predefined performance goal of 18% (10% clinical margin). Midline incisions will be closed by the small bites closure technique with a minimum 4:1 suture-to-wound length ratio and reinforced by mesh placement in the retrorectus position. The primary outcome will be IH occurrence at 12-month postoperatively, evaluated both clinically and by ultrasound. Secondary outcomes will include mesh-related and postoperative complications, surgical characteristics, IH incidence at 2 and 3 years after surgery, and quality of life.

Discussion

Currently, no conclusive evidence is available for synthetic resorbable meshes in a prophylactic setting to prevent IH. The MARS study will be the first prospective cohort study to investigate resorbable synthetic meshes and small bites closure to reduce IH incidence.

Surgical site occurrence after prophylactic use of mesh for prevention of incisional hernia in midline laparotomy: systematic review and meta-analysis of randomized clinical trials

BACKGROUND

The use of mesh is the standard for the prevention of incisional hernia (IH). However, the effect of surgical site occurrence (SSO) has never been compared. The aim of this meta-analysis was to evaluate the prevalence of SSO and measure its negative effect through the calculation of the number needed to treat for net effect (NNT net).

METHODS

A meta-analysis was performed according to the PRISMA guidelines. The primary objective was to determine the prevalence of SSO and IH, and the secondary objective was to determine the NNT net as a metric to measure the combined benefits and harms. Only published clinical trials were included. The risk of bias was analyzed, and the random effects model was used to determine statistical significance.

RESULTS

A total of 15 studies comparing 2344 patients were included. The incidence of IH was significantly lower in the mesh group than in the control group, with an OR of 0.29 (95% CI 0.16-0.49, p = 0.0001). The incidence of SSO was higher in the mesh group than in the control group, with an OR of 1.21 (95% CI 0.85-1.72, p = 0.0001) but without statistical significance. Therefore, the way to compare the benefits and risks of each of the studies was done with the calculation of the NNT net, which is the average number of patients who need to be treated to see the benefit exceeding the harm by one event, and the result was 5, which is the average number of patients who need to be treated to see the benefit exceeding the harm by one event.

CONCLUSION

The use of mesh reduces the prevalence of IH and it does not increases the prevalence of SSO, the NNT net determined that the use of mesh continues to be beneficial for the patient.

Wound healing and hernia after abdominal aortic aneurysm repair: Onlay self-gripping polyester mesh reinforcement compared with small bite sutured closure

BACKGROUND

Prophylactic mesh implantation following open surgical repair of abdominal aortic aneurysm is a debatable subject.

OBJECTIVE

To assess the efficacy of a self-gripping polyester mesh used in on-lay technique to prevent incisional hernia after open abdominal aortic aneurysm repair.

METHODS

We retrospectively reviewed the records of 495 patients who underwent aortic surgery between May 2017 and May 2021. Patients included in the study underwent open surgical repair for infrarenal abdominal aortic aneurysm (AAA) with closure of the abdominal wall with either small bite suture technique or prophylactic mesh reinforcement. Primary endpoint of the study was the occurrence of incisional hernia during a two-year follow-up period. Secondary endpoints were mesh-related complications.

RESULTS

Mesh implantation with the on-lay technique was successful in all cases. No patient in the mesh group developed an incisional hernia during the 24-month follow-up period. Two patients in the non-mesh group developed a symptomatic incisional hernia during the follow-up period at 6 months. Three cases of post-operative access site complications were observed in the mesh group.

CONCLUSIONS

Application of a self-gripping polyester mesh using the on-lay technique demonstrates acceptable early-durability after open surgical repair of abdominal aortic aneurysms. However, it appears to be associated with a number of post-operative access site complications.

Hernia Prevention: The Role of Technique and Prophylactic Mesh to Prevent Incisional Hernias

Millions of laparotomies are performed annually, carrying up to a 41% risk of developing into a hernia. Incisional hernias are associated with morbidity, mortality, and costs; an estimated $9.6 billion is spent annually on repair of ventral hernias. Although repair is possible, surgeons must prevent incisional hernias from occurring. There is substantial evidence on surgical technique to reduce the risk of incisional hernia formation. This article aims to critically summarize the use of surgical technique and prophylactic mesh augmentation during fascial closure to inform decision-making and reduce incisional hernia formation.

ECLAPTE: Effective Closure of LAParoTomy in Emergency-2023 World Society of Emergency Surgery guidelines for the closure of laparotomy in emergency settings

Laparotomy incisions provide easy and rapid access to the peritoneal cavity in case of emergency surgery. Incisional hernia (IH) is a late manifestation of the failure of abdominal wall closure and represents frequent complication of any abdominal incision: IHs can cause pain and discomfort to the patients but also clinical serious sequelae like bowel obstruction, incarceration, strangulation, and necessity of reoperation. Previous guidelines and indications in the literature consider elective settings and evidence about laparotomy closure in emergency settings is lacking. This paper aims to present the World Society of Emergency Surgery (WSES) project called ECLAPTE (Effective Closure of LAParoTomy in Emergency): the final manuscript includes guidelines on the closure of emergency laparotomy.

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.

Prophylactic Mesh Reinforcement for Prevention of Midline Incisional Hernias: A Publication Bias Adjusted Meta-analysis

OBJECTIVE

To systematically review the published literature on the use of prophylactic mesh reinforcement of midline laparotomy closures for prevention of VIH.

SUMMARY OF BACKGROUND DATA

VIH are common complications of abdominal surgery. Prophylactic mesh has been proposed as an adjunct to prevent their occurrence.

METHODS

PubMed, Embase, Scopus, and Cochrane were reviewed for RCTs that compared prophylactic mesh reinforcement versus conventional suture closure of midline abdominal surgery. Primary outcome was the incidence of VIH at postoperative follow-up ≥24 months. Secondary outcomes included surgical site infection and surgical site occurrence (SSO). Pooled risk ratios were obtained through random effect meta-analyses and adjusted for publication bias. Network meta-analyses were performed to compare mesh types and locations.

RESULTS

Of 1969 screened articles, 12 RCTs were included. On meta-analysis there was a lower incidence of VIH with prophylactic mesh [11.1% vs 21.3%, Relative risk (RR) = 0.32; 95% confidence interval (CI) = 0.19-0.55, P < 0.001), however, publication bias was highly likely. When adjusted for this bias, prophylactic mesh had a more conservative effect (RR = 0.52; 95% CI = 0.39-0.70). There was no difference in risk of surgical site infection (9.1% vs 8.9%, RR = 1.08, 95% CI = 0.82-1.43; P = 0.118), however, prophylactic mesh increased the risk of SSO (14.2% vs 8.9%, RR = 1.57, 95% CI = 1.19-2.05; P < 0.001).

CONCLUSION

Current RCTs suggest that in mid-term follow-up prophylactic mesh prevents VIH with increased risk for SSO. There is limited long-term data and substantial publication bias.

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.

Incidence and risk factors for incisional hernia after open abdominal aortic aneurysm repair

INTRODUCTION

Incisional hernia (IH) is common after open abdominal aortic aneurysm (AAA) repair. Recent studies reported incidence rates higher than previously stated. The aim of this study was to quantify the IH incidence after open AAA surgery. The secondary outcome was to identify the risk factors associated with the development of an IH.

METHODS

Retrospective observational study of all consecutive patients who underwent an open repair of AAA, from January 2010 to June 2018, at our institution. Patients were free of abdominal wall hernias at the moment of inclusion in the study. Data were extracted from electronic records: baseline characteristics, surgical factors, and postoperative events. Computed tomography (CT) scans performed during follow-up were analyzed.

RESULTS

A total of 157 patients were analysed. The IH incidence after open repair of AAA was 46.5% (73 patients). The median time for IH development was 24.43 months (IQR: 10.40-45.27), while the median follow-up time was 37.20 months (IQR: 20.53-64.12). The risk factors linked to IH were: active (HR: 4.535; 95% CI: 1.369-15.022) or previous smoking habit (HR: 4.652; 95% CI: 1.430-15.131), chronic kidney disease (HR: 2.007; 95% CI: 1.162-3.467) and previous abdominal surgery (HR: 1.653; 95% CI: 1.014-2.695).

CONCLUSION

The incisional hernia after open abdominal aortic aneurysm repair affected a high proportion of the intervened patients. Previous abdominal surgery, chronic kidney disease, and smoking habit were independent factors for the development of an incisional hernia.

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.

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.

Failure of Abdominal Wall Closure: Prevention and Management

This article reviews evidence-based techniques for abdominal closure and management strategies when abdominal wall closures fail. In particular, optimal primary fascial closure techniques, the role of prophylactic mesh, considerations for combined hernia repair, closure techniques when the fascia cannot be closed primarily, and management approaches for fascial dehiscence are reviewed.

Incidence and risk factors for incisional hernia after open abdominal aortic aneurysm repair

INTRODUCTION

Incisional hernia (IH) is common after open abdominal aortic aneurysm (AAA) repair. Recent studies reported incidence rates higher than previously stated. The aim of this study was to quantify the IH incidence after open AAA surgery. The secondary outcome was to identify the risk factors associated with the development of an IH.

METHODS

Retrospective observational study of all consecutive patients who underwent an open repair of AAA, from January 2010 to June 2018, at our institution. Patients were free of abdominal wall hernias at the moment of inclusion in the study. Data were extracted from electronic records: baseline characteristics, surgical factors, and postoperative events. Computed tomography (CT) scans performed during follow-up were analyzed.

RESULTS

A total of 157 patients were analysed. The IH incidence after open repair of AAA was 46.5% (73 patients). The median time for IH development was 24.43 months (IQR: 10.40-45.27), while the median follow-up time was 37.20 months (IQR: 20.53-64.12). The risk factors linked to IH were: active (HR: 4.535; 95% CI: 1.369-15.022) or previous smoking habit (HR: 4.652; 95% CI: 1.430-15.131), chronic kidney disease (HR: 2.007; 95% CI: 1.162-3.467) and previous abdominal surgery (HR: 1.653; 95% CI: 1.014-2.695).

CONCLUSION

The incisional hernia after open abdominal aortic aneurysm repair affected a high proportion of the intervened patients. Previous abdominal surgery, chronic kidney disease, and smoking habit were independent factors for the development of an incisional hernia.

Abdominal incision defect following AAA-surgery (AIDA): 2-year results of prophylactic onlay-mesh augmentation in a multicentre, double-blind, randomised controlled trial

The reported incidence of incisional hernia following repair of abdominal aortic aneurysm (AAA) via midline laparotomy is up to 69%. This prospective, multicenter, double-blind, randomised controlled trial was conducted at eleven hospitals in Germany. Patients aged 18 years or older undergoing elective AAA-repair via midline incision were randomly assigned using a computer-generated randomisation sequence to one of three groups for fascial closure: with long-term absorbable suture (MonoPlus^®, group I), long-term absorbable suture and onlay mesh reinforcement (group II) or extra long-term absorbable suture (MonoMax^®, group III). The primary endpoint was the incidence of incisional hernia within 24 months of follow-up, analysed by intention to treat. Physicians conducting the postoperative visits and the patients were blinded. Between February 2011 and July 2013, 104 patients (69.8 ± 7.7 years) were randomised, 99 of them received a study intervention. The rate of incisional hernia within 24 months was not significantly reduced with onlay mesh augmentation compared to primary suture (p = 0.290). Furthermore, the rate of incisional hernia did not differ significantly between fascial closure with slow and extra long-term absorbable suture (p = 0.111). Serious adverse events related to study intervention occurred in five patients (5.1%) from treatment groups II and III. Wound healing disorders were more frequently seen after onlay mesh implantation on the day of discharge (p = 0.010) and three (p = 0.009) and six (p = 0.023) months postoperatively. The existing evidence on prophylactic mesh augmentation in patients undergoing AAA-repair via midline laparotomy probably needs critical review. As the implementation of new RCTs is considered difficult due to the increasing number of endovascular AAA treated, registry studies could help to collect and evaluate data in cases of open AAA-repair. Comparisons between prophylactic mesh implantation and the small bite technique are also required. Trial registration: ClinicalTrials.gov Identifier: NCT01353443. Funding Sources: Aesculap AG, Tuttlingen, Germany.

Prophylactic Onlay Mesh Repair (POMR) Versus Primary Suture Repair (PSR) for Prevention of Incisional Hernia (IH) After Abdominal Wall Surgery: A Systematic Review and Meta-analysis

BACKGROUND

With many different operative techniques in use to reduce the incidence of incisional hernias (IH) following a midline laparotomy, there is no consensus among the clinicians on the efficacy and safety of any particular repair technique. This meta-analysis compares the prophylactic onlay mesh repair (POMR) and primary suture repair (PSR) for the incidence of IH.

METHODS

A meta-analysis and systematic review of MEDLINE, PubMed Central (via PubMed), Embase (via Ovid), SCOPUS, ScienceDirect, Google Scholar, SCI and Cochrane Library databases were undertaken. Seven randomized controlled trials assessing the outcomes of PSR and POMR were analyzed in accordance with the PRISMA statement. The risk of bias was assessed using the Rob2 tool.

RESULTS

According to the pooled analysis, POMR significantly reduced the incidence of IH compared to the PSR (OR 5.82 [95% CI 2.69, 12.58] P < 0.01) with a significantly higher seroma formation rate post-surgery (OR 0.35 [95% CI 0.18, 0.67] P < 0.01). Furthermore, the length of hospital stay (WMD -0.78 [95% CI -1.58, 0.02] P = 0.05) was significantly shorter for PSR compared to POMR group. Comparable effects were noted for reintervention, postoperative ileus, postoperative hematoma, postoperative mortality, long-term intervention and long-term deaths between the two groups.

CONCLUSIONS

POMR significantly reduces the risk of IH when compared to the PSR, with an increased risk of postoperative seroma formation and longer hospital stay. However, more RCTs with standardized protocols are needed for meaningful comparisons of the two interventions, along with longer duration of follow-up to assess the impact on the occurrence of IH.

Prophylactic Mesh After Midline Laparotomy: Evidence is out There, but why do Surgeons Hesitate?

BACKGROUND

Incisional hernias have an impact on patients' quality of life and on health care finances. Because of high recurrence rates despite mesh repair, the prevention of incisional hernias with prophylactic mesh reinforcement is currently a topic of interest. But only 15% of surgeons are implementing it, mainly because of fear for mesh complications and disbelief in the benefits. The goal of this systematic review is to evaluate the effectiveness and safety of prophylactic mesh in adult patients after midline laparotomy.

METHODS

An extensive literature search was performed in PubMed, Embase and CENTRAL until 9/5/2020 for RCTs and cohort studies regarding mesh reinforcement versus primary suture closure of a midline laparotomy. The quality of the articles was analyzed using the Scottish Intercollegiate Guidelines Network checklists. Revman 5 was used to perform a meta-analysis.

RESULTS

Twenty-three articles were found with a total of 1633 patients in the mesh reinforcement group and 1533 in the primary suture group. An odds ratio for incisional hernia incidence of 0.37 (95% CI = [0.30, 0.46], p < 0.01) with RCTs and of 0.15 (95% CI = [0.09,0.25], p < 0.01) in cohort studies was calculated. Seroma rate shows a significant odds ratio of 2.18 (95% CI = [1.45, 3.29], p < 0.01) in favor of primary suture. No increase was found regarding other complications.

CONCLUSION

The evidence for the use of prophylactic mesh reinforcement is overwhelming with a significant reduction in incisional hernia rate, but implementation in daily clinical practice remains limited. Instead of putting patients at risk for incisional hernia formation and subsequent complications, surgeons should question their arguments why not to use mesh reinforcement, specifically in high-risk patients.

Prophylactic Mesh Placement for the Prevention of Incisional Hernia in High-Risk Patients After Abdominal Surgery: A Systematic Review and Meta-Analysis

Background and objectives

In high-risk populations, the efficacy of mesh placement in incisional hernia (IH) prevention after elective abdominal surgeries has been supported by many published studies. This meta-analysis aimed at providing comprehensive and updated clinical implications of prophylactic mesh placement (PMP) for the prevention of IH as compared to primary suture closure (PSC).

Materials and methods

PubMed, Science Direct, Cochrane, and Google Scholar were systematically searched until March 3, 2020, for studies comparing the efficacy of PMP to PSC in abdominal surgeries. The main outcome of interest was the incidence of IH at different follow-up durations. All statistical analyses were carried out using Review Manager version 5.3 (The Nordic Cochrane Centre, The Cochrane Collaboration, 2014) and Stata 11.0 (Stata Corporation LP, College Station, TX). The data were pooled using the random-effects model, and odds ratio (OR) and weighted mean differences (WMD) were calculated with the corresponding 95% confidence interval (CI).

Results

A total of 3,330 were identified initially and after duplicate removal and exclusion based on title and abstract, 26 studies comprising 3,000 patients, were included. The incidence of IH was significantly reduced for PMP at follow-up periods of one year (OR= 0.16 [0.05, 0.51]; p=0.002; I²=77%), two years (OR= 0.23 [0.12, 0.45]; p<0.0001; I²=68%), three years (OR= 0.30 [0.16, 0.59]; p=0.0004; I²= 52%), and five years (OR=0.15 [0.03, 0.85]; p=0.03; I²=87%). However, PMP was associated with an increased risk of seroma (OR=1.67 [1.10, 2.55]; p= 0.02; I²=19%) and chronic wound pain (OR=1.71 [1.03, 2.83]; p= 0.04; I²= 0%). No significant difference between the PMP and PSC groups was noted for postoperative hematoma (OR= 1.04 [0.43, 2.50]; p=0.92; I²=0%), surgical site infection (OR=1.09 [0.78, 1.52]; p= 0.62; I²=12%), wound dehiscence (OR=0.69 [0.30, 1.62]; p=0.40; I²= 0%), gastrointestinal complications (OR= 1.40 [0.76, 2.58]; p=0.28; I²= 0%), length of hospital stay (WMD= -0.49 [-1.45, 0.48]; p=0.32; I²=0%), and operating time (WMD=9.18 [-7.17, 25.54]; p= 0.27; I²=80%).

Conclusions

PMP has been effective in reducing the rate of IH in the high-risk population at all time intervals, but it is associated with an increased risk of seroma and chronic wound pain. The benefits of mesh largely outweigh the risk, and it is linked with positive outcomes in high-risk patients.

Can We Predict Incisional Hernia?: Development of a Surgery-specific Decision-Support Interface

OBJECTIVE

The aim of this study was to identify procedure-specific risk factors independently associated with incisional hernia (IH) and demonstrate the feasibility of preoperative risk stratification through the use of an IH risk calculator app and decision-support interface.

SUMMARY BACKGROUND DATA

IH occurs after 10% to 15% of all abdominal surgeries (AS) and remains among the most challenging, seemingly unavoidable complications. However, there is a paucity of readily available, actionable tools capable of predicting IH occurrence at the point-of-care.

METHODS

Patients (n = 29,739) undergoing AS from 2005 to 2016 were retrospectively identified within inpatient and ambulatory databases at our institution. Surgically treated IH, complications, and costs were assessed. Predictive models were generated using regression analysis and corroborated using a validation group.

RESULTS

The incidence of operative IH was 3.8% (N = 1127) at an average follow-up of 57.9 months. All variables were weighted according to β-coefficients generating 8 surgery-specific predictive models for IH occurrence, all of which demonstrated excellent risk discrimination (C-statistic = 0.76-0.89). IH occurred most frequently after colorectal (7.7%) and vascular (5.2%) surgery. The most common occurring risk factors that increased the likelihood of developing IH were history of AS (87.5%) and smoking history (75%). An integrated, surgeon-facing, point-of-care risk prediction instrument was created in an app for preoperative estimation of hernia after AS.

CONCLUSIONS

Operative IH occurred in 3.8% of patients after nearly 5 years of follow-up in a predictable manner. Using a bioinformatics approach, risk models were transformed into 8 unique surgery-specific models. A risk calculator app was developed which stakeholders can access to identify high-risk IH patients at the point-of-care.

Prevention of incisional hernia after midline laparotomy with prophylactic mesh reinforcement: a meta-analysis and trial sequential analysis

Background

Incisional hernia is a frequent complication after abdominal surgery. The aim of this study was to assess the efficacy of prophylactic mesh reinforcement (PMR) after midline laparotomy in reducing the incidence of incisional hernia.

Methods

A meta‐analysis was conducted following PRISMA guidelines. The primary outcome was the incidence of incisional hernia after follow‐up of at least 12 months. Secondary outcomes were postoperative complications. Only RCTs were included. A random‐effects model was used for the meta‐analysis, and trial sequential analysis was conducted.

Results

Twelve RCTs were included, comprising 1815 patients. The incidence of incisional hernia was significantly lower after PMR compared with sutured closure (risk ratio (RR) 0·35, 95 per cent c.i. 0·21 to 0·57; P < 0·001). Both onlay (RR 0·26, 0·11 to 0·67; P = 0·005) and retromuscular (RR 0·28, 0·10 to 0·82; P = 0·02) PMR led to a significant reduction in the rate of incisional hernia. The occurrence of seroma was higher in patients who had onlay PMR (RR 2·23, 1·10 to 4·52; P = 0·03). PMR did not result in an increased rate of surgical‐site infection.

Conclusion

PMR of a midline laparotomy using an onlay or retromuscular technique leads to a significant reduction in the rate of incisional hernia in high‐risk patients. Individual risk factors should be taken into account to select patients who will benefit most.

[Correction added on 19 February 2020, after first online publication: J. García Alamino has been amended to J. M. Garcia‐Alamino]

Abdominal Closure and the Risk of Incisional Hernia in Aneurysm Surgery - A Systematic Review and Meta-analysis

OBJECTIVES

Patients with abdominal aortic aneurysms (AAAs) have a high prevalence of incisional hernia following open repair. The choice of incision and closure technique has a significant impact on this post-operative complication. Multiple techniques exist, as well as various comparative analyses, but clinical consensus is lacking. The objective was to perform a systematic review and meta-analysis of AAA laparotomy and closure technique and the risk of incisional hernia development.

METHODS

The systematic review was performed according to the PRISMA guidelines. A literature search of all original research published until January 2019 was made. Outcome measures were surgical approach, closure technique, hernia rates, length of follow up, and method of hernia recognition. Groups were divided according to method of abdominal incision and closure technique. Differences in outcome between closure techniques were expressed as risk ratios with 95% confidence interval (CI) using a random effects model.

RESULTS

Fifteen studies were included with a cumulative cohort of between 388 and 3 399 patients compared in each group. Abdominal closure with a suture to wound length ratio of more than 4:1 compared with less than 4:1, RR 0.42 (95% CI 0.27-0.65), and abdominal closure with mesh compared with without mesh augmentation, RR 0.24 (95% CI 0.10-0.60) reduced the risk of incisional hernia. There were no significant differences in incisional hernia rate between transverse abdominal incision vs. vertical midline incision, RR 0.57 (95% CI 0.31-1.06) and between midline transperitoneal vs. all retroperitoneal incisions, RR 1.19 (95% CI 0.54-2.61).

CONCLUSION

Choice of abdominal closure technique after aneurysm surgery impacts the risk of developing incisional hernia. The use of a supportive mesh significantly reduces the risk of incisional hernia in vertical midline incisions. The same is true if a suture to wound ratio of more than 4:1 is used.

Prophylactic Intraperitoneal Onlay Mesh Following Midline Laparotomy-Long-Term Results of a Randomized Controlled Trial

OBJECTIVES

Incisional hernia, a serious complication after laparotomy, is associated with high morbidity and costs. This trial examines the value of prophylactic intraperitoneal onlay mesh to reduce the risk of incisional hernia after a median follow-up time of 5.3 years.

METHODS

We conducted a parallel group, open-label, single center, randomized controlled trial (NCT01003067). After midline incision, the participants were either allocated to abdominal wall closure according to Everett with a PDS-loop running suture reinforced by an intraperitoneal composite mesh strip (Group A) or the same procedure without the additional mesh strip (Group B).

RESULTS

A total of 276 patients were randomized (Group A = 131; Group B = 136). Follow-up data after a median of 5.3 years after surgery were available from 183 patients (Group A = 95; Group B = 88). Incisional hernia was diagnosed in 25/95 (26%) patients in Group A and in 46/88 (52%) patients in Group B (risk ratio 0.52; 95% CI 0.36-0.77; p < 0.001). Eighteen patients with asymptomatic incisional hernia went for watchful waiting instead of hernia repair and remained free of symptoms after of a median follow-up of 5.1 years. Between the second- and fifth-year follow-up period, no complication associated with the mesh could be detected.

CONCLUSION

The use of a composite mesh in intraperitoneal onlay position significantly reduces the risk of incisional hernia during a 5-year follow-up period.

TRIAL REGISTRATION NUMBER

Ref. NCT01003067 (clinicaltrials.gov).

Does perfusion matter? Preoperative prediction of incisional hernia development

PURPOSE

Incisional hernias complicate 12-15% of general surgery cases with higher rates reported after laparotomy for aortoiliac occlusive disease (10-17%) and aneurysmal disease (17-38%). We hypothesize that inadequate perfusion of the abdominal wall promotes future hernia development.

METHODS

Thirty-eight patients undergoing midline laparotomy or thoracoabdominal approach for aortic disease with at least 2 years of follow-up were included in the study. Preoperative imaging was reviewed to assess vessel patency, contributing to the abdominal wall perfusion. Patency of the superior epigastric artery was determined at the T10 level, the inferior epigastric artery at the L4 level, and the deep circumflex iliac artery at the anterior superior iliac spine. Lumbar arteries were considered patent if they were seen branching from the aorta. Clinic notes and hospital medical records were reviewed to evaluate the hernia development post-procedure.

RESULTS

Thirteen patients (34%) developed an incisional hernia. Absent flow from bilateral superior epigastric arteries or absent flow from ipsilateral superior and inferior epigastric arteries was found to be predictive of hernia development (P = 0.013, 0.011, respectively). There was no association identified with perfusion from the lumbar or deep circumflex iliac arteries.

CONCLUSIONS

Absent patency of the abdominal wall vasculature is a novel risk factor for incisional hernia development in the setting of aortic disease. Preoperative assessment of perfusion may convey the risk of hernia development and may be a tool to guide measures such as prophylactic mesh placement to reduce the future risk of incisional hernia.

Systematic review of the stage of innovation of biological mesh for complex or contaminated abdominal wall closure

Background

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

Methods

A systematic review was performed of published and ongoing studies between January 2000 and September 2017. Eligible studies were those where a biological mesh was used to support fascial closure, either prophylactically after midline laparotomy, or for reinforcement after repair of incisional hernia with midline incision. The primary outcome measure was the IDEAL framework stage of innovation. The key secondary outcome measure was the GRADE criteria for study quality.

Results

Thirty‐five studies including 2681 patients were included. Four studies considered mesh prophylaxis, 23 considered hernia repair, and eight reported on both. There was one published randomized trial (IDEAL stage 3), none of which was of high quality; the others were non‐randomized studies (IDEAL stage 2a). A detailed description of surgical technique was provided in most studies (27 of 35); however, no study reported outcomes according to the European Hernia Society consensus statement and only two described quality control of surgical technique during the study. From 21 ongoing randomized trials and observational studies, 11 considered repair of incisional hernia and 10 considered prophylaxis (seven in elective settings).

Conclusion

The evidence base for biological mesh is limited, and better reporting and quality control of surgical techniques are needed. Although results of ongoing trials over the next decade will improve the evidence base, further study is required in the emergency and contaminated settings.

Role of Prophylactic Mesh Placement for Laparotomy and Stoma Creation

Incisional and parastomal hernias are a cause of significant morbidity and have a substantial effect on quality of life and economic costs for patients and hospital systems. Although many aspects of abdominal hernias are understood, prevention is a feature that is still being realized. This article reviews the current literature and determines the utility of prophylactic mesh placement in prevention of incisional and parastomal hernias.

Prophylactic Mesh Reinforcement versus Sutured Closure to Prevent Incisional Hernias after Open Abdominal Aortic Aneurysm Repair via Midline Laparotomy: A Systematic Review and Meta-Analysis

OBJECTIVE/BACKGROUND

Incisional hernia is a frequent late complication after open abdominal aortic aneurysm (AAA) repair. We aimed to determine whether prophylactic mesh reinforcement of the abdominal wall at open AAA repair via midline laparotomy reduces the rate of incisional hernia compared to standard sutured closure.

METHODS

A systematic review and meta-analysis was carried out in accordance with the PRISMA statement (PROSPERO registration CRD42017072508). Randomised controlled trials (RCTs) comparing prophylactic mesh reinforcement with standard sutured closure were eligible for inclusion. MEDLINE, Embase, and the Cochrane Library were searched. A meta-analysis with a random effects model was carried out to estimate pooled risk ratios (RR) with 95% confidence intervals (CIs) for the incidence of, and re-operation rate for, incisional hernias. Assessments of methodological quality, quality of evidence, and strength of recommendations were done with the Cochrane Collaboration's tool for assessing risk of bias and the GRADE approach.

RESULTS

Four RCTs with a total of 388 patients were included in the meta-analysis. Pooled analysis showed that mesh reinforcement significantly reduced the risk of incisional hernia after AAA repair compared with standard sutured closure (RR 0.27, 95% CI 0.11-0.66). The pooled rate of re-operations was not different between groups (RR 0.23, 95% CI 0.11-1.05). Mesh reinforcement did not cause more intra-operative or post-operative complications than sutured closure. The risk of bias in studies was low and the quality of evidence was rated as moderate.

CONCLUSION

Prophylactic mesh reinforcement of the abdominal wall after open AAA repair via midline laparotomy significantly reduces the risk of incisional hernia. However, no significant difference in re-operation for incisional hernia was found.

Prophylactic meshes in the abdominal wall

BACKGROUND

There is a high incidence of incisional hernias in specific high-risk patient populations. For these patients, the prophylactic placement of mesh during closure of the abdominal wall incision has been investigated in several prospective studies.

OBJECTIVE

This article aims to summarize and synthetize the currently available evidence on prophylactic meshes in a narrative review.

MATERIALS AND METHODS

Systematic reviews were performed on the use of prophylactic meshes in different indications: midline laparotomies, stoma reversal wounds, and permanent stoma.

RESULTS

High-quality data from randomized trials shows that prophylactic synthetic non-absorbable mesh implantation is safe and effective, both in prevention of incisional hernias after midline laparotomies and during construction of an elective end colostomy. It should be considered in patients with a high risk for incisional hernia development, such as those receiving open abdominal aortic aneurysm, obesity, or colorectal cancer surgery. It is strongly recommended for construction of an elective permanent end colostomy. For midline laparotomies, both the retromuscular and onlay positions of a prophylactic mesh seem equally effective and safe. For parastomal hernia prevention, only the retromuscular prophylactic mesh and its use for end colostomies has been proven to be effective and safe. No data support the choice of a biological mesh or a synthetic absorbable mesh over a non-absorbable synthetic mesh, even in clean-contaminated surgical procedures. No data yet support the standard use of prophylactic mesh when closing the wound during closure of a temporary stoma.

CONCLUSION

Prophylactic mesh implantation should be standard of care during construction of an elective end colostomy and will become standard of care for midline laparotomies in patients at a high risk of incisional hernias.

Cross-Linked Cholecyst-Derived Extracellular Matrix for Abdominal Wall Repair

Abdominal wall repair frequently utilizes either nondegradable or biodegradable meshes, which are found to stimulate undesirable biological tissue responses or which possess suboptimal degradation rate. In this study, a biologic mesh prototype made from carbodiimide cross-linked cholecyst-derived extracellular matrix (EDCxCEM) was compared with small intestinal submucosa (Surgisis^®), cross-linked bovine pericardium (Peri-Guard^®), and polypropylene (Prolene^®) meshes in an in vivo rabbit model. The macroscopic appearance and stereological parameters of the meshes were evaluated. Tailoring the degradation of the EDCxCEM mesh prevents untimely degradation, while allowing cellular infiltration and mesh remodeling to take place in a slower but predictable manner. The results suggest that the cross-linked biodegradable cholecyst-derived biologic mesh results in no seroma formation, low adhesion, and moderate stretching of the mesh. In contrast to Surgisis, Peri-Guard, and Prolene meshes, the EDCxCEM mesh showed a statistically significant increase in the volume fraction (V_v) of collagen (from 34% to 52.1%) in the central fibrous tissue region at both day 28 and 56. The statistically high length density (L_v), of blood vessels for the EDCxCEM mesh at 28 days was reflected also by the higher cellular activity (high V_v of fibroblast and moderate V_v of nuclei) indicating remodeling of this region in the vicinity of a slowly degrading EDCxCEM mesh. The lack of mesh area stretching/shrinkage in the EDCxCEM mesh showed that the remodeled tissue was adequate to prevent hernia formation. The stereo-histological assays suggest that the EDCxCEM delayed degradation profile supports host wound healing processes including collagen formation, cellular infiltration, and angiogenesis. The use of cross-linked CEM for abdominal wall repair is promising.

Incisional hernia prevention and use of mesh. A narrative review

Incisional hernias are a very common problem, with an estimated incidence around 15-20% of all laparotomies. Evisceration is another important problem, with a lower rate (2.5-3%) but severe consequences for patients. Prevention of both complications is an essential objective of correct patient treatment due to the improved quality of life and cost savings. This narrative review intends to provide an update on incisional hernia and evisceration prevention. We analyze the current criteria for proper abdominal wall closure and the possibility to add prosthetic reinforcement in certain cases requiring it. Parastomal, trocar-site hernias and hernias developed after stoma closure are included in this review.

The State of Prophylactic Mesh Augmentation

Prophylactic mesh augmentation (PMA) is the implantation of mesh during closure of an index laparotomy to decrease a patient's risk for developing incisional hernia (IH). The current body of evidence lacks refined guidelines for patient selection, mesh placement, and material choice. The purpose of this study is to summarize the literature and identify areas of research needed to foster responsible and appropriate use of PMA as an emerging technique. We conducted a comprehensive review of Scopus, Cochrane, PubMed, and clinicaltrials.gov for articles and trials related to using PMA for IH risk reduction. We further supplemented our review by including select papers on patient-reported outcomes, cost utility, risk modeling, surgical techniques, and available materials highly relevant to PMA. Five-hundred-fifty-one unique articles and 357 trials were reviewed. Multiple studies note a significant decrease in IH incidence with PMA compared with primary suture-only–based closure. No multicenter randomized control trial has been conducted in the United States, and only two such trials are currently active worldwide. Evidence exists supporting the use of PMA, with practical cost utility and models for selecting high-risk patients, but standard PMA guidelines are lacking. Although Europe has progressed with this technique, widespread adoption of PMA requires large-scale pragmatic randomized control trial research, strong evidence-based guidelines, current procedural terminology coding, and resolution of several barriers.

Comparative Cellular Local Response in Abdominal Defect Plastic Surgery with Bovine Pericardium and Bovine Fascia Preserved in Formaldehyde in Experimental Rabbits

In the present paper, we refer to a method of primary closure of congenital defects of the anterior abdominal wall with tensionless viscero-abdominal disproportion. The study group included 10 animals subjected to surgery of the abdominal wall defect closure with bovine pericardium graft preserved in 0.5% formaldehyde, and 5 rabbits of the same breed and weight, in which bovine fascia graft was used as implant, being preserved in 0.5% formaldehyde. The abdominal anterior wall defect was made surgically by excision of the musculo-fascial structures and peritoneum. Bovine pericardium graft and bovine fascia graft were placed and fixed posteriorly to rectus abdominals muscles, having direct contact with the intra-abdominal contents and protected by suturing skin and subcutaneous layer.

The purpose of the study was to perform a comparative postoperative evaluation of local macroscopic and microscopic changes that develop after reconstruction of the major abdominal wall defects experimentally induced in rabbits, using bovine pericardium and bovine fascia grafts preserved in 0.5% formaldehyde.

In cases of major fascial defects of the anterior abdominal wall, bovine pericardium graft has acceptable strength and biocompatibility, having stabilizing properties of the abdominal wall due to the development of the connective tissue layer located between the implant and the subcutaneous layer. Bovine fascia grafts preserved in formaldehyde have an insignificant irritating and inflammatory action on the intestinal loops compared with bovine pericardium, and do not induce the development of a significant abdominal adhesion process, this allowing their use in the abdominal fascial defects closure with placement in direct contact with the abdominal contents.

Does prophylactic mesh placement in elective, midline laparotomy reduce the incidence of incisional hernia? A systematic review and meta-analysis

BACKGROUND

Operative intervention to correct incisional hernia affects 150,000 patients annually, with 1 in 3 repairs recurring within 9 years. The aim of this study was to compare the incidence of incisional hernia and postoperative complications in elective midline laparotomy patients after the use of prophylactic mesh placement and primary suture closure.

METHODS

A systematic review was performed to identify studies comparing prophylactic mesh placement to primary suture closure in elective, midline laparotomy at index abdominal aponeurosis closure. The primary outcome was incisional hernia. Secondary outcomes included postoperative complications.

RESULTS

Fourteen studies were included (2,114 patients), with 1,152 receiving prophylactic mesh placement. Prophylactic mesh placement decreased the risk of incisional hernia overall when compared to primary suture closure (relative risk = 0.15; P < .00001) and in trials using only polypropylene mesh versus 4:1 primary suture closure (relative risk = 0.15; P = .003). Prophylactic mesh placement reduced the risk of incisional hernia regardless of mesh location or composition: onlay (relative risk = 0.07; P < .0001), retrorectus (relative risk = 0.04; P = .002), and preperitoneal (relative risk = 0.18; P = .02). Prophylactic mesh placement increased risk of seroma overall (relative risk = 1.95; P < .0001), onlay (relative risk = 2.43; P = .01) and preperitoneal (relative risk = 1.47; P = .01) but not retrorectus plane (relative risk = 1.55; P = .26). Polypropylene mesh increased seroma risk only in the onlay position (relative risk = 2.77; P = .04). Prophylactic mesh placement patients are at increased risk for chronic wound pain compared to primary suture closure (relative risk = 1.70; P = .03).

CONCLUSION

Prophylactic mesh placement is associated with an 85% postoperative incisional hernia risk reduction when compared to primary suture closure in at-risk patients undergoing elective, midline laparotomy closure. This technique appears to be safe with comparable complication profiles, barring an increased risk of seroma, especially with the onlay technique, and the possibility for an increased risk of chronic pain. Despite this verification, evidence from large domestic trials that sufficiently addresses major knowledge gaps is simply lacking.

Prevention of Incisional Hernias with Biological Mesh: A Systematic Review of the Literature

Background

Prophylactic mesh-augmented reinforcement during closure of abdominal wall incisions has been proposed in patients with increased risk for development of incisional hernias (IHs). As part of the BioMesh consensus project, a systematic literature review has been performed to detect those studies where MAR was performed with a non-permanent absorbable mesh (biological or biosynthetic).

Methods

A computerized search was performed within 12 databases (Embase, Medline, Web-of-Science, Scopus, Cochrane, CINAHL, Pubmed publisher, Lilacs, Scielo, ScienceDirect, ProQuest, Google Scholar) with appropriate search terms. Qualitative evaluation was performed using the MINORS score for cohort studies and the Jadad score for randomized clinical trials (RCTs).

Results

For midline laparotomy incisions and stoma reversal wounds, two RCTs, two case–control studies, and two case series were identified. The studies were very heterogeneous in terms of mesh configuration (cross linked versus non-cross linked), mesh position (intraperitoneal versus retro-muscular versus onlay), surgical indication (gastric bypass versus aortic aneurysm), outcome results (effective versus non-effective). After qualitative assessment, we have to conclude that the level of evidence on the efficacy and safety of biological meshes for prevention of IHs is very low. No comparative studies were found comparing biological mesh with synthetic non-absorbable meshes for the prevention of IHs.

Conclusion

There is no evidence supporting the use of non-permanent absorbable mesh (biological or biosynthetic) for prevention of IHs when closing a laparotomy in high-risk patients or in stoma reversal wounds. There is no evidence that a non-permanent absorbable mesh should be preferred to synthetic non-absorbable mesh, both in clean or clean-contaminated surgery.

Prevention of Incisional Hernias by Prophylactic Mesh-augmented Reinforcement of Midline Laparotomies for Abdominal Aortic Aneurysm Treatment: A Randomized Controlled Trial

BACKGROUND

The incidence of incisional hernias after abdominal aortic aneurysm repair is high. Prophylactic mesh-augmented reinforcement during laparotomy closure has been proposed in patients at high risk of incisional hernia.

METHODS

A multicenter randomized trial was conducted on patients undergoing elective abdominal aortic aneurysm repair through a midline laparotomy (Clinical.Trials.gov: NCT00757133). In the study group, retromuscular mesh-augmented reinforcement was performed with a large-pore polypropylene mesh (Ultrapro, width 7.5 cm). The primary endpoint was the incidence of incisional hernias at 2-year follow-up.

RESULTS

Between February 2009 and January 2013, 120 patients were recruited at 8 Belgian centers. Patients' characteristics at baseline were similar between groups. Operative and postoperative characteristics showed no difference in morbidity or mortality. The cumulative incidence of incisional hernias at 2-year follow-up after conventional closure was 28% (95% confidence interval [CI], 17%-41%) versus 0% (95% CI, 0%-6%) after mesh-augmented reinforcement (P < 0.0001; Fisher exact test). The estimated "freedom of incisional hernia" curves (Kaplan-Meier estimate) were significantly different across study arms (χ = 19.5, P < 0.0001; Mantel-Cox test). No adverse effect related to mesh-augmented reinforcement was observed, apart from an increased mean time to close the abdominal wall for mesh-augmented reinforcement compared with the control group: 46 minutes (SD, 18.6) versus 30 minutes (SD, 18.5), respectively (P < 0.001; Mann-Whitney U test).

CONCLUSIONS

Prophylactic retromuscular mesh-augmented reinforcement of a midline laparotomy in patients with abdominal aortic aneurysm is safe and effectively prevents the development of incisional hernia during 2 years, with an additional mean operative time of 16 minutes.