J. M. Bellón

Active matrix metalloproteinase-2 upregulation in the abdominal skin of patients with direct inguinal hernia.

Eur J Clin Invest 2010; 40 (12): 1113–1121

Efficiency of 4% Icodextrin in Preventing Adhesions to Spiral Tacks Used to Fix Intraperitoneal Prostheses

Background/Aims: This study was designed to evaluate the extent of adhesion formation to prostheses fixed with spiral tacks and to establish whether the use of Ringer’s lactate or icodextrin could prevent these adhesions. Methods:24New Zealand white rabbits weighing around 3,000 g were implanted with a 7 × 5 cm patch of ePTFE (DualMesh®) through amidline laparotomy. The prosthesis was fixed to the intact peritoneum using spiral tacks. Three study groups were established according to whether the animals were: implanted with ePTFE fixed with spiral tacks or implanted with ePTFE fixed with spiral tacks and simultaneously administered Ringer’s lactate or 4% icodextrin in the peritoneal cavity. Adhesion formation and prosthetic behavior at the prosthesis/peritoneal interface were evaluated and quantified by sequential laparoscopy performed at 3, 7 and 14 days. Results: Adhesions generally formed on the tacks and were classified as the fully integrated type. No significant differences were observed in terms of the extent of adhesions or of neoperitoneal thickness between control animals and those receiving Ringer’s lactate or icodextrin. Conclusions: (a)Prosthesis-fixing tacks induced adhesions; (b) the use of substances such as icodextrin or Ringer’s lactate does not seem to diminish adhesion formation, and (c) the use of icodextrin offered no benefits over that of Ringer’s lactate solution.

Prostheses size dependency of the mechanical response of the herniated human abdomen

BackgroundHernia repairs still exhibit clinical complications, i.e. recurrence, discomfort and pain and mesh features are thought to be highly influent. The aim of this study is to evaluate the impact of the defect size and mesh type in an herniated abdominal wall using numerical models.MethodsTo do so, we have started from a FE model based on a real human abdomen geometry obtained by MRI, where we have provoked an incisional hernia of three different sizes. The surgical procedure was simulated by covering the hernia with a prostheses, and three surgical meshes with distinct mechanical properties were used for the hernia repair: an isotropic heavy-weight mesh (Surgipro@), a slightly anisotropic light-weight mesh (Optilene@) and a highly anisotropic medium-weight mesh (Infinit@). The mechanical response of the wall to a high intraabdominal pressure (corresponding to a coughing motion) was analyzed here.ResultsOur findings suggest that the anisotropy of the mesh becomes more relevant with the increase of the defect size. Additionally, according to our results Optilene@ showed the closest deformation to the natural distensibility of the abdomen while Infinit@ should be carefully used due to its excessive compliance.

Biomechanical and histologic evaluation of two application forms of surgical glue for mesh fixation to the abdominal wall.

The use of an adhesive for mesh fixation in hernia repair reduces chronic pain and minimizes tissue damage in the patient. This study was designed to assess the adhesive properties of a medium-chain (n-butyl) cyanoacrylate glue applied as drops or as a spray in a biomechanical and histologic study. Both forms of glue application were compared to the use of simple-loose or continuous-running polypropylene sutures for mesh fixation. Eighteen adult New Zealand White rabbits were used. For mechanical tests in an ex vivo and in vivo study, patches of polypropylene mesh were fixed to an excised fragment of healthy abdominal tissue or used to repair a partial abdominal wall defect in the rabbit respectively. Depending on the fixation method used, four groups of 12 implants each or 10 implants each respectively for the ex vivo and in vivo studies were established: Glue-Drops, Glue-Spray, Suture-Simple and Suture-Continuous. Biomechanical resistance in the ex vivo implants was tested five minutes after mesh fixation. In vivo implants for biomechanical and histologic assessment were collected at 14 days postimplant. In the ex vivo study, the continuous suture implants showed the highest failure sample tension, while the implants fixed with glue showed lower failure sample tension values. However, the simple and continuous suture implants returned the highest stretch values. In the in vivo implants, failure sample tension values were similar among groups while the implants fixed with a continuous running suture had the higher stretch values, and the glue-fixed implants the lower stretch values. All meshes showed good tissue integration within the host tissue regardless of the fixation method used. Our histologic study revealed the generation of a denser, more mature repair tissue when the cyanoacrylate glue was applied as a spray rather than as drops.