Mesh-related complications and recurrence after ventral mesh rectopexy with synthetic versus biologic mesh: a systematic review and meta-analysis

Background Ventral mesh rectopexy (VMR) is a widely accepted surgical treatment for rectal prolapse. Both synthetic and biologic mesh are used. No consensus exists on the preferred type of mesh material. The aim of this systematic review and meta-analysis was to establish an overview of the current literature on mesh-related complications and recurrence after VMR with synthetic or biologic mesh to aid evidence-based decision making in preferred mesh material. Methods A systematic search of the electronic databases of PubMed, Embase and Cochrane was performed (from inception until September 2020). Studies evaluating patients who underwent VMR with synthetic or biologic mesh were eligible. The MINORS score was used for quality assessment. Results Thirty-two studies were eligible after qualitative assessment. Eleven studies reported on mesh-related complications including 4001 patients treated with synthetic mesh and 762 treated with biologic mesh. The incidence of mesh-related complications ranged between 0 and 2.4% after synthetic versus 0–0.7% after biologic VMR. Synthetic mesh studies showed a pooled incidence of mesh-related complications of 1.0% (95% CI 0.5–1.7). Data of biologic mesh studies could not be pooled. Twenty-nine studies reported on the risk of recurrence in 2371 synthetic mesh patients and 602 biologic mesh patients. The risk of recurrence varied between 1.1 and 18.8% for synthetic VMR versus 0–15.4% for biologic VMR. Cumulative incidence of recurrence was found to be 6.1% (95% CI 4.3–8.1) and 5.8% (95% CI 2.9–9.6), respectively. The clinical and statistical heterogeneity was high. Conclusions No definitive conclusions on preferred mesh type can be made due to the quality of the included studies with high heterogeneity amongst them.

O13 BIOLOGIC VERSUS SYNTHETIC MESH IN VENTRAL HERNIA REPAIR: PARTICIPANT-LEVEL ANALYSIS OF TWO RANDOMIZED CONTROLLED TRIALS AT ONE YEAR

Aim Biologic mesh has been increasingly utilized in complex ventral hernia repair despite limited evidence at low risk of bias supporting its growth. We hypothesized biologic mesh when compared to synthetic mesh would have fewer major complications at one year. Material and Methods We performed a participant-level meta-analysis of published randomized controlled trials (RCTs) comparing biologic to synthetic mesh at one year. Primary outcome was major complication (composite of mesh infection, recurrence, reoperation, or death) at one year post-operative. Secondary outcomes included length of index hospital stay, surgical site occurrence, and surgical site infection. Outcomes were assessed using frequentist generalized linear models. Results A total of 252 patients from two RCTs were included, 126 patients randomized to the intervention arm of biologic mesh and 126 patients randomized to the control of synthetic mesh. Median follow-up was 15 (12, 27) months. Major complication occurred in 41 (33%) patients randomized to biologic mesh, and 44 (35%) patients randomized to synthetic mesh, (relative risk [RR] 0.91, 95% confidence interval [CI] 0.54-1.55, p-value 0.740). There were 36 total recurrences, 23 (18%) in the biologic arm, and 13 (10%) in the synthetic arm (RR 1.83, 95% CI 0.84-3.99, p-value 0.130). The remainder of outcomes demonstrated no statistically significant differences. Conclusions The risk of major complication did not differ between biologic versus synthetic mesh. In patients undergoing ventral hernia repair, there was no clinical benefit with biologic mesh as opposed to synthetic mesh at one year post-operative.

P014 COMPARATIVE EFFECTIVENESS OF RESORBABLE SYNTHETIC ONLAY AND BIOLOGIC INTRAPERITONEAL MESH FOR ABDOMINAL WALL RECONSTRUCTION: A 2-YEAR MATCHED PAIR ANALYSIS

Aim The literature currently lacks comparative studies examining the relative effectiveness of anatomic planes and mesh selection when combating abdominal wall reconstruction (AWR), particularly when the retrorectus sublay space is not available. The aim of this study was to examine the efficacy of resorbable synthetic mesh onlay (RSOM) plane against biologic mesh in the intraperionteal plane (BIPM). Methods A single center, two surgeon, 5-year retrospective review (2014-2019) was performed examining subjects who underwent AWR in the onlay plane with resorbable synthetic mesh or the intraperitoneal plane with biologic mesh. A matched paired analysis was conducted. Data examining demographic characteristics, intraoperative variables, post-operative outcomes, and costs were analyzed. Results A total of 88 subjects (44 per group) were identified (median follow-up: 24.5 months). The mean age was 57.7 years, with a mean BMI of 30.4 kg/m2. The average defect size was 292 ± 237 cm2, with most wounds being clean-contaminated (48.9%), and 55% having prior failed repair. RSOM subjects were significantly less likely (4.5%) to experience recurrence compared to BIPM (22.7%; p<0.026.). Additionally, RSOM suffered less post-operative surgical site occurrences (18.2% vs. 40.9%;p<0.019) and required fewer procedural interventions (11.4% vs. 36.4%;p<0.011). RSOM was also associated with significantly less total costs ($16,658 ± 14,930) compared to BIPM ($27,645 ± 16,864;p<0.001). Conclusion When faced with hernia repair, the selection of resorbable synthetic mesh in the onlay plane may be preferable to biologic mesh place in the intraperitoneal plane due to lower long-term recurrence rates, surgical site complications, and costs.

In vivo Analysis of the Resistance of the Meshes to Escherichia coli Infection

Background: The mesh infection is mostly related to the gram-negative bacteria, such as Escherichia coli (E. coli) for emergency surgery of incarcerated hernia. However, few study investigated the effects of E. coli concentration, mesh materials and antibiotic prophylaxis on mesh infection after hernioplasty. The aim of this study was to evaluate the bacterial resistance to E. coli for three different materials of mesh, and to measure the minimum E. coli concentration for mesh infection with and without antibiotic prophylaxis in a rat model.Methods: Three types of mesh (polytetrafluoroethylene, polypropylene, and biologic meshes) were used in the repair of an acute ventral hernia rat model in the setting of different concentrations of E. coli loads and antibiotics. At the 8th day after surgery, mesh samples were sent for microbiologic and histologic analyses.Results: The positive rates of bacterial culture increased with E. coli concentration. The biologic mesh showed better bacterial resistance compared to polytetrafluoroethylene mesh and polypropylene mesh when the concentration of E. coli ranges from 106 CFU/ml to 108 CFU/ml (P = 0.002 and P = 0.029, respectively). Prophylactical ceftriaxone treatment could not decrease the colonization rate of E. coli at 106 CFU/ml or 108 CFU/ml in each group (P > 0.05). The scores of neovascularization in polypropylene mesh and biologic mesh were similar, which was higher than that of polytetrafluoroethylene mesh (P < 0.05). Compared with other meshes, biologic mesh showed better tolerance to 106 CFU/ml E. coli with respect to inflammation, depth of inflammation, neovascularization, cellular repopulation and foreign body giant cells.Conclusion: The biologic mesh had better E. coli resistance compared to polytetrafluoroethylene mesh and polypropylene mesh when the E. coli concentration is higher than 106 CFU/ml in rats. Antibiotic prophylaxis was useful when the contamination was not particularly severe.