Mid-term outcomes after biologic mesh use: Does their performance meet our expectations?

Platelet-rich plasma enhances mechanical strength of strattice in rat model of ventral hernia repair

Incisional hernia is a common complication of hernia repair despite the development of various synthetic and bio-synthetic repair materials. Poor long-term mechanical strength, leading to high recurrence rates, has limited the use of acellular dermal matrices (ADMs) in ventral hernia repair (VHR). Biologically derived meshes have been an area of increasing interest. Still these materials bring the risk of more aggressive immune response and fibrosis in addition to the mechanical failures suffered by the synthetic materials. Platelet-rich plasma (PRP), a growth-factor-rich autologous blood product, has been shown to improve early neovascularization, tissue deposition, and to decrease the rates of recurrence. Here, we demonstrate that PRP promotes the release of growth factors stromal derived factor (SDF)-1, transforming growth factor-beta, and platelet-derived growth factor in a dose-dependent manner. Additionally, we utilize an aortic ring angiogenesis assay to show that PRP promotes angiogenesis in vitro. A rat model of VHR using StratticeTM ADM demonstrates similar findings in vivo, corresponding with the increased expression of vascular endothelial growth factor and collagen type 1 alpha 1. Finally, we show that the molecular and cellular activity initiated by PRP results in an increased mechanical stiffness of the hernia repair mesh over time. Collectively, these data represent an essential step in demonstrating the utility and the mechanism of platelet-derived plasma in biomaterial-aided wound healing and provide promising preclinical data that suggest such materials may improve surgical outcomes.

Preventing Recurrence in Clean and Contaminated Hernias Using Biologic Versus Synthetic Mesh in Ventral Hernia Repair: The PRICE Randomized Clinical Trial

OBJECTIVE

The aim of this study was to evaluate which mesh type yields lower recurrence and complication rates after ventral hernia repair.

SUMMARY BACKGROUND DATA

More than 400,000 ventral hernia repairs are performed annually in the United States. Although the most effective method for repairing ventral hernias involves using mesh, whether to use biologic mesh versus synthetic mesh is controversial.

METHODS

Single-blind, randomized, controlled, pragmatic clinical trial conducted from March 2014 through October 2018; 165 patients enrolled with an average follow up of 26 months. Patients were randomized 1:1 to have their ventral hernias repaired using either a biologic (porcine) or synthetic (polypropylene) mesh. The primary study outcome measure was hernia recurrence at 2 years.

RESULTS

A total of 165 patients (68 men), mean age 55 years, were included in the study with a mean follow-up of 26 months. An intention-to-treat analysis noted that hernias recurred in 25 patients (39.7%) assigned to biologic mesh and in 14 patients (21.9%) assigned to synthetic mesh (P = 0.035) at 2 years. Subgroup analysis identified an increased rate of hernia recurrence in the biologic versus the synthetic mesh group under contaminated wound conditions (50.0% vs 5.9%; P for interaction = 0.041). Postoperative complication rates were similar for the 2 mesh types.

CONCLUSIONS

The risk of hernia recurrence was significantly higher for patients undergoing ventral hernia repair with biologic mesh compared to synthetic mesh, with similar rates of postoperative complications. These data indicate that the use of synthetic mesh over biologic mesh to repair ventral hernias is effective and can be endorsed, including under contaminated wound conditions.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02041494.

Biologic Mesh in Surgery: A Comprehensive Review and Meta-Analysis of Selected Outcomes in 51 Studies and 6079 Patients

BACKGROUND

In recent decades, biologic mesh (BM) has become an important adjunct to surgical practice. Recent evidence-based clinical applications of BM include but are not limited to: reconstruction of abdominal wall defects; breast reconstruction; face, head and neck surgery; periodontal surgery; other hernia repairs (diaphragmatic, hiatal/paraesophageal, inguinal and perineal); hand surgery; and shoulder arthroplasty. Prior systematic reviews of BM in complex abdominal wall hernia repair had several shortcomings that our comprehensive review seeks to address, including exclusion of laparoscopic repair, assessment of risk of bias, use of an acceptable meta-analytic method and review of risk factors identified in multivariable regression analyses.

MATERIALS AND METHODS

We sought articles of BM for open ventral hernia repair reporting on early complications, late complications or recurrences and included minimum of 50. We used the quality in prognostic studies risk of bias assessment tool. Random effects meta-analysis was applied.

RESULTS

This comprehensive review selected 62 articles from 51 studies that included 6,079 patients. Meta-analytic pooling found that early complications are present in about 50%, surgical site occurrences (SSOs) in 37%, surgical site infections (SSIs) in 18%, reoperation in 7%, readmission in 20% and mortality in 3%. Meta-analytic estimates of late outcomes included overall complications (42%), SSOs (40%) and SSIs (22%). Specific SSOs included seroma (14%), hematoma (4%), abscess (10%), necrosis (5%), dehiscence (8%) and fistula formation (5%). Reoperation occurred in about 17%, mesh explantation in 9% and recurrence in 36%.

CONCLUSION

Estimates of nearly all outcomes from individual studies were highly heterogeneous and sensitivity analyses and meta-regressions generally failed to explain this heterogeneity. Recurrence is the only outcome for which there are consistent findings for risk factors. Bridge placement of BM is associated with higher risk of recurrence. Prior hernia repair, history of reintervention and history of mesh removal were also risk factors for increased recurrence.