Anti‐inflammatory coatings of hernia repair meshes: A pilot study

Abstract

The current prevalence of postoperative chronic pain from hernioplasty procedures employing polymer mesh is close to 30%. Most of the researchers agree that oxidative stress, resulting from the release of oxidants and enzymes during acute inflammatory response, is a key factor in the development of posthernioplasty complications. This results in both the decrease of the biomechanical properties and stiffening of the polymer fibers of the mesh, leading to chronic pain. Moreover, enhanced activity of inflammatory cells can lead to an excessive deposition of connective tissue around the implant. In this study polypropylene hernia repair meshes coated with vitamin E (α-tocopherol), a known antioxidant, were prepared and characterized. The absorption isotherm of vitamin E on the mesh was characterized and a release profile study yielded a promising results, showing sustained release of the drug over a 10-day period. An animal study was conducted, and histological analysis five weeks after implantation exhibited a reduced host tissue response for a modified mesh as compared to a plain mesh, as evidenced by a higher mature collagen to immature collagen ratio, as well as lower level of fatty infiltrates, neovascularization and fibrosis in the case of modified mesh. These results support the use of α-tocopherol as a potential coating in attempt to reduce the extent of postoperative inflammation, and thereby improve long-term outcomes of hernioplasty. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 589-597, 2018.

Anti-inflammatory coating of hernia repair meshes: a 5-rabbit study

“…For all animals individually, the difference was statistically significant too. Additionally, little to no evidence of foreign body giant cells was found in the vicinity of either of the implants, similarly to the pilot study [20]. The numerical data are presented in Table 2.…”

“…In a pilot one-rabbit study, we showed that vitamin E-coated meshes exhibited reduced foreign body response and improved wound healing [20]. Furthermore, in vitro release of vitamin E from the coated mesh was desirably slow, with 70% of the coating remaining after 10 days of exposure to albumin solution, suggesting sustained release and long-term protection [20]. However, pilot nature of the study yielded limited statistical data.…”

“…Coating and sterilization methods were the same as in the pilot study [20]. Briefly, vitamin E was dissolved in 95% medical grade ethanol (100 mg/ml) and this solution was transferred into a 6-well plate containing pieces of surgical mesh (10 ml per well).…”

“…Anesthesia of the animals prior to surgeries was done by injection of acepromazine 1 mg/kg, ketamine HCL 33 mg/kg, atropine 0.02-0.05 mg/kg, and buprenorphine 0.05 mg/kg. Implantation surgery was performed using the same protocol as in the pilot study [20]. Following skin sterilization, a 5-cm incision was cut in the midline of the animals' abdominal wall.…”

“…The specific surface area of the meshes was determined by low-temperature nitrogen adsorption using Brunauer-Emmett-Teller (BET) analysis and was calculated to be 3.4 m 2 /g [20]. Since the maximum binding yield of vitamin E to mesh surface (~ 6 mg/in 2 ) was observed at the initial coating concentration of 100 mg/ml in the pilot study, this concentration was used in this study [20].…”