Analysis of polypropylene meshes with embedded silver ions in ventral hernia repair: can they be used in different grades of contamination?

Background: This study aimed to analyze the outcomes of patients undergoing ventral hernia repair (VHR) with a polypropylene mesh with embedded silver ions (PSM) in the context of different degrees of contamination, compared to standard conventional macroporous polypropylene mesh (PPL).

Methods: From May 2019 to October 2023, a retrospective comparative analysis of patients who underwent elective or urgent VHR with a SilverMesh (PSM group) versus standard macroporous polypropylene mesh (PPL group), based on the Spanish Hernia registry (EVEREG). The exclusion criteria were other PSM indications (groin hernia, prophylaxis) and the use of composite meshes or any material different to PPL. Each Hospital participating in the registry applied its own preoperative antibiotic protocol. The field contamination degree was assessed according the Centers for Disease Control (CDC) classification criteria. Epidemiological data, hernia characteristics, surgical and postoperative variables (Clavien-Dindo classification) of these patients were analysed.

Results: From May 2019 to October 2023, PPL group included 446 cases and PSM group 206 cases. The number of PPL cases were reduced from 2655 to 446, to try and match suitable similar cases in both groups. In PSM group, smoking (28.6% vs. 20.6%; p = 0.000), COPD (23.3% vs. 16.9%; p = 0.050), ASA class III-IV (35% vs. 29.2%; p = 0.001), prehabilitation with BTA (16% vs. 4%; p = 0.000) and PPP (5.8% vs. 0.9%; p = 0.000), and W2-W3 hernias (79.9% vs. 53.2%; p = 0.000) were more frequent than PPL group. In PSM group, complex techniques of VHR like RSR and CST (61% vs. 48%; p = 0.000), average duration of surgery (91.7 vs. 69.9 min; p = 0.032) and mean length of stay (5.4 vs. 4.7 days; p = 0.034) were more frequent than PPL group. The overall rate of short-term SSO was slightly lower in PSM than PPL group (30.5% vs. 33.7%; p = 0.155) though statistically insignificant. No mesh infection was reported in PSM group versus 7 cases in PPL group, although this was not statistically significant.

Conclusions: The use of PSM for VHR in different degrees of contamination and without a significant superiority over PPL, leads to favourable results, especially in overall rate of SSO and CMI, in patients with preoperative risk factors, large hernias and complex hernia repairs. Being the first clinical study performed with this prosthesis, further comparative studies with longer follow-up are needed to explore further.