P029 HOW DOES THE MADRID APPROACH WORK

Aim The Madrid APPROACH is the combination of an absorbable mesh and a permanent retromuscular mesh for the treatment of the complex abdominal wall problems. It has been controversial because of the need of two different meshes. We present a clinic case to show the utility of this technique and how it allows rebuilding the inguinal ligament. Material and Methods 78 years old woman who underwent a right ilioinguinal and obturatriz lymphadenectomy due to a melanoma. Incisional hernia fixed in 2018 with a retromuscular polyester mesh. New incisional iliac hernia (L3) over the right iliac vessels, with an absence of inguinal ligament, right rectus atrophy, and the previous mesh being part of the sac. Surgery: incision over the previous scar. Wide dissection of the preperitoneal space, Retzius space and lateral to the cuadratus lumborum, retrodiafragmatic dissection, lateral transverse abdominus release, and cross-over to the retrorectal left space. Preperitoneal BioA mesh and an upper 40x40cm medium weight polipropilene mesh set to both Cooper ligaments. Results After two and a half months, a PET-TC showed the BioA mesh perfectly adapted to the abdominal wall and rebuilt a new inguinal ligament. Also intense FDG capitation of the mesh due to the high cellular metabolism. Two years later the patient has a continent abdominal wall, the follow up TC shows the disappearance of the absorbable mesh and the perfect abdominal wall rebuilt. Conclusions The BioA mesh acts like a tissue scaffold for new conjunctive tissue as we see the intense FDG captation. The Madrid APPROACH allows giving response to very complex abdominal wall problems.

Long term outcome and elasticity of a polyester mesh used for laparoscopic ventral hernia repair

Background Repair of a ventral hernia is increasingly being performed by a laparoscopic approach despite lack of good long term follow up data on outcomes. The aim of this study was to examine the long term performance of a polyester mesh and to assess its elastic properties in patients undergoing laparoscopic ventral hernia repair. Methods All patients being assessed for a ventral hernia repair between August 2011 and November 2013 were placed on a prospective database. Those undergoing laparoscopic repair with a polyester mesh were seen at clinic at one month and one year, while their electronic records were assessed at 34 months (range 24–48 months) and 104 months (range 92–116 months). In addition, CT scans of the abdomen and pelvis performed for any reason on these patients during the follow up period were reviewed by a consultant gastrointestinal radiologist. Mechanical failure testing of the mesh was also performed. Results Thirty-two of the 100 patients assessed for ventral hernia repair had a laparoscopic repair with a polyester mesh. Nineteen (59%) had CT scans performed during the follow-up period. No recurrence was recorded at 34 months, while three (9.4%) had a recurrence at 104 months. Two had central breakdown of the mesh at 81 and 90 months, while 1 presented acutely at 116 months after operation. Mesh had stretched across the defect by an average of 21% (range 5.7–40%) in nine patients. Mechanical testing showed that this mesh lost its elasticity at low forces ranging between 1.8 and 3.2 N/cm. Conclusion This study shows that late recurrence is a problem following laparoscopic ventral hernia repair with polyester mesh. The mesh loses it elasticity at a low force. This combined with degradation of mesh seems the most likely cause of failure. This is unlikely to be a unique problem of polyester mesh and further long-term studies are required to better assess this operative approach to ventral hernia repair.

Effect of Loop Length On Thermal Comfort Properties of Mesh Knitted Fabrics

In this study, it is aimed to change the loop length of knitted fabrics with a mesh structure and to investigate the effect of loop length differences on thermal and moisture transmission properties. For this purpose, six fabrics with different loop lengths were produced in two different knittings and yarn types. Thermal conductivity, thermal absorptivity, thermal resistance, air permeability and moisture management properties of these fabrics were measured according to standard test methods. The results showed that as the yarn gets finer and loop length increases, the air permeability values will increase. It was observed that as the loop length increase, the overall moisture management capacity (OMMC) and thermal absorptivity of the fabrics will decrease. The thermal resistance values of two ply textured polyester mesh knitted fabrics decreased with increasing density and the highest loop length two ply textured polyester mesh knitted fabric showed the highest thermal resistance value.

A TISSUE REACTION TO COMBINED HERNIA PROSTHESIS AT DIFFERENT POSTOPERATIVE P

Our experimental study shows a morphological response of the anterior abdominal wall to implantation of a combined (bovine pericardium graft and polyester mesh) hernia prosthesis. For this purpose, fifteen chinchillas were operated on. A combined prosthesis was implanted intra-abdominally, where the pericardium graft adjoined the internal organs with the smooth side, while the synthetic material was facing the peritoneum. Morphological and morphometric assessment of the tissue in the area of implantation of the prosthesis was carried out. Morphology of tissues samples was evaluated in 2 weeks, in 1 month and in 2 months after surgery. Our study revealed that the combined prosthesis implanted in the anterior abdominal wall causes an acute inflammatory response, which progresses within a month after the surgery. However, the signs of inflammation reduced at the end of the second month of the experiment. A new connective tissue grew actively into the implant from the side of the polyester mesh. The pericardium graft adjacent to the abdominal cavity with the smooth side did not cause formation of connective tissue. Thus, the combined hernia prosthesis has protected the abdominal cavity from adhesions in the postoperative period.

An improved method for in vitro feeding of adult female Dermanyssus gallinae (poultry red mite) using Baudruche membrane (goldbeater’s skin)

Background Dermanyssus gallinae, or poultry red mite (PRM), is an important ectoparasite in laying hen, having a significant effect on animal welfare and potentially causing economic loss. Testing novel control compounds typically involves in vitro methodologies before in vivo assessments. Historically, in vitro methods have involved PRM feeding on hen blood through a membrane. The use of hen blood requires multiple procedures (bleeds) to provide sufficient material, and the use of a larger species (e.g. goose) could serve as a refinement in the use of animals in research. Methods The in vitro feeding device used was that which currently employs a Parafilm™ M membrane (Bartley et al.: Int J Parasitol. 45:819–830, 2015). Adult female PMR were used to investigate any differences in mite feeding, egg laying and mortality when fed goose or hen blood. Effects on these parameters when PRM were fed through either the Parafilm™ M membrane or the Baudruche membrane alone or through a combination of the membrane with an overlaid polyester mesh were tested using goose blood. Results Poultry red mites fed equally well on goose or hen blood through the Parafilm™ M membrane, and there were no significant differences in mortality of PRM fed with either blood type. A significant increase (t test: t = 3.467, df = 4, P = 0.03) in the number of eggs laid per fed mite was observed when goose blood was used. A 70% increase in PRM feeding was observed when the mites were fed on goose blood through a Baudruche membrane compared to when they were fed goose blood through the Parafilm™ M membrane. The addition of an overlaid polyester mesh did not improve feeding rates. A significant increase (analysis of variance: F(3, 20) = 3.193, P = 0.04) in PRM egg laying was observed in mites fed on goose blood through the Baudruche membrane compared to those fed goose blood through the Parafilm™ M membrane. A mean of 1.22 (standard error of the mean ± 0.04) eggs per fed mite was obtained using the Baudruche feeding device compared to only 0.87 (SEM ± 0.3) eggs per fed mite using the Parafilm™ M device when neither was combined with a polyester mesh overlay. Conclusion The in vitro feeding of adult female PRM can be readily facilitated through the use of goose blood in feeding devices with the Baudruche membrane.