Lightweight Polypropylene Research Articles

Optimal management of mesh infection: Evidence and treatment options

Mesh reinforcement is generally considered the standard of care in ventral hernia repair. Infection is a common complication following ventral hernia repair. Infection extending to the mesh is a complex problem. Knowledge of current treatment strategies is necessary for surgeons performing abdominal wall reconstruction. A comprehensive literature review was performed of current literature to assess risk factors and treatment options for mesh infection. Modifiable risk factors for mesh infections include active smoking, poorly controlled diabetes mellitus, abdominal skin or wound issues, and obesity. Operative factors that increase the risk of mesh infection include prior hernia repair, enterotomy and contamination of the surgical field. Of the synthetic meshes, lightweight polypropylene has the highest likelihood of salvage. Patients that are current smokers, those with other synthetic mesh types, and those infected with MRSA are rarely salvaged. Following excision of infected mesh, multi-staged abdominal wall reconstruction can be considered. Biologic or biosynthetic mesh is recommended when repairing incisional hernias following excision of infected mesh and likely represent the patient's best chance at a definitive hernia repair. Wound VAC-assisted delayed primary closure should be considered in higher-risk patients. Mesh infection is a complex complication that is commonly encountered by surgeons performing hernia repair. Prevention through patient optimization should be performed whenever appropriate. However, when patients develop a mesh infection, most will require complete mesh excision and recurrent hernia repair.

Влияние аутоплазмы, обогащенной тромбоцитами, на прочность и эластичность брюшной стенки при надапоневротической имплантации легкого полипропиленового эндопротеза (экспериментальное исследование)

The results of the experimental study of the abdominal wall after supraaponeurotic endoprosthesis with a lightweight polypropylene implant with and without introducing autoplasma enriched with platelets into the implantation zone conducted on chinchilla rabbits. The study of the abdominal wall strength and elasticity was carried out with a tensile testing machine REM-02-1. The indicators of relative elongation in standard and breaking load were recorded as well as the breaking load of tissue. The results of the study showed that introduction of autoplasma enriched with platelets can increase the elasticity and strength of the abdominal wall. The developed technology of stimulation of reparative processes in the abdominal wall tissue after endoprosthesis is technically simple, economically feasible and safe for patients. The conducted researches allow recommending the stimulation of reparative processes in hernioplastica with autoplasma enriched with platelets for further clinical tests.

Continuous ultrasound‐assisted fabrication of lightweight polypropylene foam with low thermal conductivity and excellent sound insulation properties

Ultrasonic oscillation as a new polymer processing technology, was introduced into the polymer melt to improve the high melt strength Polypropylene (HMSPP) foaming ability, the effect of the ultrasonic oscillation power, Azodicarbonamide (AC) and talc content on the cell morphology, cell size, apparent density, cell density and nucleation density of the HMSPP foam was systematically studied. When the ultrasound and talc were introduced into the HMSPP melt, the HMSPP foam had a larger cell density and smaller the size as well as more uniform distribution. Interestingly, when the talc was introduced into the HMSPP, the cell morphologies changed from sphere to oval. Compared to the HMSPP foam without ultrasonic oscillation, the minimum thermal conductivity of the HMSPP foam with ultrasonic power 100 W reached 0.055 W/mK. When the talc was introduced into HMSPP melt, the average sound transmission loss value of the HMSPP foam were enhanced, and reached 30.37 dB, which was 13.7% higher than that of the HMSPP foam without talc and ultrasonic oscillation. The ultrasonic‐assisted extrusion foaming had a promising to construct a new method to continuously and rapidly fabricate polymer foam with low thermal conductivity and excellent sound insulation properties. POLYM. ENG. SCI., 58:1678–1684, 2018. © 2017 Society of Plastics Engineers

Patterns of Recurrence and Mechanisms of Failure after Open Ventral Hernia Repair with Mesh

Recurrence after ventral hernia repair (VHR) remains a significant complication. We sought to identify the technical aspects of VHR associated with recurrence. Patients who underwent open midline VHR between 2006 and 2013 (n = 261) were retrospectively evaluated. Patients with recurrence (Group 1, n = 48) were compared with those without recurrence (Group 2, n = 213). Smoking, diabetes, and body mass index were not different between groups. More patients in Group 1 underwent clean-contaminated, contaminated, or dirty procedures (43.8 vs 27.7%; P = 0.021). Group 1 had a higher incidence of surgical site occurrence (52.1 vs 32.9%; P = 0.020) and surgical site infection (43.8 vs 15.5%; P < 0.001). Recurrences were due to central mesh failure (CMF) (39.6%), midline recurrence after biologic or bioabsorbable mesh repair (18.8%), superior midline (16.7%), lateral (16.7%), and after mesh explantation (12.5%). Most CMF (78.9%) occurred with light-weight polypropylene (LWPP). Recurrence was higher if the midline fascia was unable to be closed. Recurrence with midweight polypropylene (MWPP) was lower than biologic (P < 0.001), bioabsorbable (P = 0.006), and light-weight polypropylene (P = 0.046) mesh. Fixation, component separation technique, and mesh position were not different between groups. Wound complications are associated with subsequent recurrence, whereas midweight polypropylene is associated with a lower overall risk of recurrence and, specifically, CMF.

Remarkably improved electrical insulating performances of lightweight polypropylene nanocomposites with fullerene

A polypropylene/fullerene nanocomposite was fabricated via solution processing with good dispersion of the fullerene nanoparticles. It was observed that a small amount of fullerene (~1 wt. ‰) can significantly improve the direct current (DC) electrical insulation performance (i.e. improved space charge distribution, greater DC dielectric breakdown strength, and larger DC volume resistivity) of polypropylene. Thermally stimulated depolarization current tests indicate that fullerene doping remarkably increases the deep trap density of pure polypropylene. The mechanisms by which the electrical properties of the polypropylene nanocomposites were improved are the introduction of deep traps and the high electron affinity of fullerene. The deep traps result from the interfaces between polypropylene and fullerene. This work provides a potential method to tailor lightweight nanodielectric materials with excellent electrical insulating performances.

ОСОБЛИВОСТІ ДИНАМІКИ СИСТЕМНИХ ПОКАЗНИКІВ ЦИТОКІНІВ НА ІМПЛАНТАЦІЮ ЛЕГЕНЬ І ВАЖКИХ СІТОК ЗА УМОВ РЕТРОМУСКУЛЯРНОЇ ПЛАСТИКИ У ПАЦІЄНТІВ ІЗ ПІСЛЯОПЕРАЦІЙНОЮ ВЕНТРАЛЬНОЮ ГРИЖЕЮ

Використання поліпропіленових сіток у хірургії післяопераційних вентральних гриж є беззаперечним. Про те їх використання супроводжується вираженою запальною реакцією у ділянці імплантації, сприяє формуванню грубої сполучнотканинної капсули і, як наслідок, призводить до зморщування сітки. Невирішеним залишається питання післяопераційних ексудативних ускладнень, які значно ускладнюють післяопераційний перебіг.Мета дослідження – провести порівняльну оцінку результатів використання двох поліпропіленових сіток фірми “УКРТЕХМЕД” – “легкої” крупнопористої Омега-2 та “важкої” Омега-4 на основі вивчення стану системних показників цитокінів з одночасною порівняльною оцінкою сонографічного дослідження зони імплантації за умов виконання ретромускулярної алогерніопластики у пацієнтів із післяопераційною вентральною грижею.Матеріали і методи. Обстежено 42 пацієнти, оперовані на післяопераційну вентральну грижу. Першу групу дослідження склали 20 (47,6 %) пацієнтів, у яких використовували “важкий” ендопротез Омега-4, другу групу – 22 (52,4 %) пацієнти, яким імплантовано “легку” сітку Омега-2. В обох групах проводили дослідження системних показників цитокінів. У сироватці периферійної крові визначали відношення про- та протизапальних інтерлейкінів TNF-α, IL-8 та IL-4 на 3; 5; 7; 9 та 11 доби післяопераційного періоду з метою оцінки стадійності та каскадності імунної відповіді на імплантацію поліпропіленової сітки. Усім пацієнтам в післяопераційному періоді виконували динамічний сонографічний моніторинг, на предмет контролю вираженості ексудативної реакції в ділянці імплантації.Результати досліджень та їх обговорення. Відмічено, що при імплантації обох типів ендопротезів виникає запальна реакція місцевих тканин, яка супроводжується ступінчастим підвищенням прозапальних та протизапальних цитокінів. Достовірно відмічено більш раннє і тривале підвищення концентраціі прозапальних цитокінів TNF-α та IL-8 і низьку концентрацію протизапальних цитокінів IL-4 у пацієнтів з імплантацією “важкої” сітки Омега-4 “УКРТЕХМЕД” і, як наслідок, більш виражений і пролонгований запальний процес з тривалою ексудативною фазою, що підтверджується даними, отриманими при проведенні сонографічного моніторингу, порівняно з групою хворих, у яких використовували “легку” сітку Омега-2, що визначає її переваги за умов виконання алогерніопластики при післяопераційних вентральних грижах.Висновки. Використання легких поліпропіленових сіток у хірургії післяопераційних вентральних гриж супроводжується незначним запальним процесом і короткою ексудативною фазою в зоні імплантації, що, у свою чергу, зменшує значну кількість післяопераційних ускладнень і сприяє швидкій реабілітації оперованих хворих.

Female genital prolapse surgery using ultra lightweight polypropylene mesh

To compare the results of female genital prolapse (FGP) surgery via vaginal access using lightweight and ultra-lightweight polypropylene mesh. From 2007 to 2011, 93 women aged from 46 to 71 years with II-IV stage FGP (POP-Q classification) were examined and underwent the vaginal extra-peritoneal colpopexy using polypropylene implants in the Department of Urology. Patients were divided into 2 groups. In patients of group 1 (n=50) the surgery was performed according to a newly developed technique using perforated ultra-lightweight (surface density 19 g/m2) domestically manufactured polypropylene implant. In group 2, a standard trocar set with light (surface density of 42.7 g/m2) foreign-made polypropylene implants was used. Long-term follow-up was from 1 to 5 years. General surgical complications (urinary bladder injury, blood loss over 300 ml, perineal and vaginal hematomas) were detected in 2 (4%) patients of group 1 and in 7 (16.3%) patients of group 2. The most common specific mesh-related complication was the vaginal wall erosion, which was observed in 4 (9.3%) patients of group 2 and in 1 (2%) patient of group 1. FGP recurrence was diagnosed in 5 (10%) patients of group 1 in the non-treated part and in 8 (18.6%) patients of group 2. Three patients (7%) in group 2 developed recurrent cystocele due to the shrinkage of the mesh implant which was not observed in group 1. At 12 month follow-up, the results of FGP surgical treatment were estimated as good (full functional recovery and no FGP recurrence) in 41 (82%) and 32 (74.4%) patients of groups 1 and 2, respectively. We have developed a method of vaginal extra-peritoneal colpopexy using a perforated ultra-lightweight polypropylene implant. This technique has resulted in the absence of recurrence in the treated part of FGP, and 4.1, 4.2 and 4.7 fold reductions in the incidence of general surgical complications, vaginal wall erosions and perineal and vaginal hematomas, respectively, compared with FGP patients undergoing the placement of the lightweight polypropylene implant using the standard trocar set.

Extracellular Matrix Regenerative Graft Attenuates the Negative Impact of Polypropylene Prolapse Mesh on Vagina in Rhesus Macaque

(Abstracted from Am J Obstet Gynecol 2017;216:153.e1–153.e9) Use of wide pore lightweight polypropylene mesh in an effort to improve anatomic outcomes in the surgical repair of prolapse has been associated with significant mesh-related complications. A widely used implanted polypropylene mesh (Gynemesh) has been shown to induce a host immune foreign-body response and degenerative changes in the vagina when implanted via sacrocolpopexy.

Fabrication and evaluation of a warp knitted polypropylene/polylactic acid composite mesh for pelvic floor repair

Surgical mesh for repairing pelvic defects is expected to be stiff to improve surgical convenience, as well as be soft and flexible to relieve foreign body sensation. This paper aims to develop a new composite mesh (PA) consisted of polypropylene (PP) monofilaments and polylactic acid (PLA) monofilaments according to this expectation. The PA mesh was designed by the two-bar warp knitting technique to have a knitted structure with light weight (19.9 g/m2) and high porosity (porosity). A commercial lightweight PP mesh—Surgimesh® Prolapse mesh—was used as the control group. The mechanical property, in vitro degradation, and in vivo biocompatibility were then measured. The results revealed that the addition of stiffer, stronger PLA monofilaments did not significantly strengthen PA mesh, but made the mesh stiff. The warp knitted structure, porosity and pore size are vital factors affecting mesh mechanical properties. PLA monofilaments in PA mesh were degraded in 74 weeks, with a maximum weight loss reaching 62.4%. PA mesh was demonstrated to have better biocompatibility with evidences of lower shrinkage (13.1%) and faster tissue growth speed.

Randomized clinical trial of mesh fixation with glue or sutures for Lichtenstein hernia repair

Pain is the most likely reason for delay in resuming normal activities after groin hernia repair. The primary aim of this study was to determine whether the use of glue to fix the mesh instead of sutures reduced acute postoperative pain after inguinal hernia repair. Secondary objectives were to compare postoperative complications, chronic pain and early recurrence rates during 1-year follow-up. Some 370 patients who underwent Lichtenstein hernia repair were randomized to receive either glue (Histoacryl®) or non-absorbable polypropylene sutures for fixation of lightweight polypropylene mesh. Postoperative complications, pain and recurrence were evaluated by an independent blinded observer. Postoperative pain at 8 h, 24 h, 7 days and 30 days was less when glue was used instead of sutures for all measures (P < 0·001). The operation was significantly quicker using glue (mean(s.d.) 35·3(8·7) min versus 39·9(11·1) min for sutures; P < 0·001). There were no significant differences between the groups in terms of postoperative complications, chronic pain and early recurrence at 1-year follow-up. Atraumatic mesh fixation with glue was quicker and resulted in less acute postoperative pain than sutures for Lichtenstein hernia repair. Registration number: NCT02632097 (http://www.clinicaltrials.gov).

Physical structure and mechanical properties of knitted hernia mesh materials: A review

Mesh implantation for hernia repair is one of the common surgical techniques. The goal of this review is to highlight the basic requirements of mesh in order to select the most appropriate hernia mesh considering mesh type, physical properties and mechanical properties. Textile warp-knitted synthetic meshes have significantly decreased recurrence rate of hernia. Polypropylene light weight mesh with antimicrobial coating is taking attention of researchers due to its improved compliance, infection resistance, hydrophobicity, inert nature and strong material. Composite meshes have better tissue incorporation, reduced shrinkage and improved mechanical properties. The mesh porosity is an important factor to predict the biocompatibility of all meshes. Usually, large pore size meshes are better than small pore size meshes because of their flexibility, decreased shrinkage, reduced scar bridging and increased tissue ingrowth. All synthetic and composite meshes have higher strength than the human abdominal wall. Mesh type, mesh structure, mechanical properties and mesh implantation techniques are important factors for hernia repair. It is critical to understand the physical structure and mechanical properties of mesh material in relation to human abdominal wall. Moreover, mesh surface functionalization and grafting with plasma is a new development technique to enhance the loading of antimicrobial agent for the prevention of mesh infection.

Extracellular matrix regenerative graft attenuates the negative impact of polypropylene prolapse mesh on vagina in rhesus macaque

The use of wide pore lightweight polypropylene mesh to improve anatomical outcomes in the surgical repair of prolapse has been hampered by mesh complications. One of the prototype prolapse meshes has been found to negatively impact the vagina by inducing a decrease in smooth muscle volume and contractility and the degradation of key structural proteins (collagen and elastin), resulting in vaginal degeneration. Recently, bioscaffolds derived from extracellular matrix have been used to mediate tissue regeneration and have been widely adopted in tissue engineering applications. Here we aimed to: (1) define whether augmentation of a polypropylene prolapse mesh with an extracellular matrix regenerative graft in a primate sacrocolpopexy model could mitigate the degenerative changes; and (2) determine the impact of the extracellular matrix graft on vagina when implanted alone. A polypropylene-extracellular matrix composite graft (n= 9) and a 6-layered extracellular matrix graft alone (n= 8) were implanted in 17 middle-aged parous rhesus macaques via sacrocolpopexy and compared to historical data obtained from sham (n= 12) and the polypropylene mesh (n= 12) implanted by the same method. Vaginal function was measured in passive (ball-burst test) and active (smooth muscle contractility) mechanical tests. Vaginal histomorphologic/biochemical assessments included hematoxylin-eosin and trichrome staining, immunofluorescent labeling of α-smooth muscle actin and apoptotic cells, measurement of total collagen, collagen subtypes (ratio III/I), mature elastin, and sulfated glycosaminoglycans. Statistical analyses included 1-way analysis of variance, Kruskal-Wallis, and appropriate post-hoc tests. The host inflammatory response in the composite mesh-implanted vagina was reduced compared to that following implantation with the polypropylene mesh alone. The increase in apoptotic cells observed with the polypropylene mesh was blunted in the composite (overall P < .001). Passive mechanical testing showed inferior parameters for both polypropylene mesh alone and the composite compared to sham whereas the contractility and thickness of smooth muscle layer in the composite were improved with a value similar to sham, which was distinct from the decreases observed with polypropylene mesh alone. Biochemically, the composite had similar mature elastin content, sulfated glycosaminoglycan content, and collagen subtype III/I ratio but lower total collagen content when compared to sham (P= .011). Multilayered extracellular matrix graft alone showed overall comparable values to sham in aspects of the biomechanical, histomorphologic, or biochemical endpoints of the vagina. The increased collagen subtype ratio III/I with the extracellular matrix graft alone (P= .033 compared to sham) is consistent with an ongoing active remodeling response. Mesh augmentation with a regenerative extracellular matrix graft attenuated the negative impact of polypropylene mesh on the vagina. Application of the extracellular matrix graft alone had no measurable negative effects suggesting that the benefits of this extracellular matrix graft occur when used without a permanent material. Future studies will focus on understanding mechanisms.

Résultats, tolérance et satisfaction des patientes à 6 mois d’une cure de cystocèle par voie vaginale avec pose de prothèse

To assess at 6 months the efficiency, the safety and the satisfaction of a lightweight polypropylene mesh used for the transvaginal repair of cystocele by bilateral anterior sacrospinous ligament fixation (NUVIA™ SI). A prospective cohort study was performed from January 2014 to June 2015. Preoperative assessment included an evaluation using the Pelvic Organ Prolapse Quantification system (POP-Q) and 3 questionnaires about symptoms, quality of life and quality of sex life (PFDI-20, PFIQ7, PISQ-12). Results were evaluated by a composite criteria: Ba≤0, absence of bulge sensation and absence of reoperation for cystocele recurrence. Secondary objectives were to assess the complications rates and patient's satisfaction. In 10 months, 16 patients, with a mean age of 61.9±8.8years, were included and evaluated by an independent observator at 6months. Four patients were sexually active before surgery and 5 at 6 months. Results were optimal in 93.75% cases (15/16) with one intraoperative injury (bladder injury) and one postoperative complication (increase of preoperative dyspareunia). Satisfaction rate was 93.75% (15/16) and questionnaires PFDI-20 and PFIQ-7 were statistically improved (P<0.0001 and P=0.0013). Three patients had a reintervention but not about anterior wall prolapse (section of a suburethral sling for urinary retention, suburethral sling exposure and cure of stress urinary incontinence). At short term, transvaginal mesh repair by anterior sacrospinous ligament fixation with NUVIA™ presents 93.75% optimal result with one case of increased dyspareunia and 3 reoperations which don't concern anterior wall (urinary outcomes). 4.

Fabrication, characterization and application of polypropylene macroporous mesh for repairing pelvic floor defects

The application of mesh to reconstruct pelvic floors is considered a state-of-the-art method for the treatment of pelvic floor dysfunction. Polypropylene (PP) is the most frequently used synthetic graft material in gynecology departments due to its good mechanical property and non-degradability. Pelvic repairing meshes are required to have good biocompatibility, stability and low shrinkage with sufficient softness. Meshes should also adhere to surrounding tissues to support pelvic organs after implantation. This work designed two kinds of lightweight PP macroporous meshes with different structures. The meshes were designed based on analyzing properties of Gynemesh® PS, which is a common pelvic repairing mesh in clinical use. The requirements of mesh design were as follows: mesh weight &lt;45 g/m2, pore size &gt;75 µm, porosity &gt;60%. Two kinds of meshes were fabricated according to design requirements and named the S1 mesh and S2 mesh. Several structural parameters, including thickness, weight, pore size, porosity and mechanical properties, including bursting strength, tensile strength, suture pulling off force and flexibility, were tested and analyzed. S1 mesh and S2 mesh were then implanted in the onlay position of rabbits for 90 days. The biocompatibility was evaluated through operation situation, postoperative recovery, mesh adhesion, shrinkage, histological evaluation of mesh and surrounding tissues. The results revealed that the two kinds of meshes were both beneficial to promote tissue growth; most animals recovered well. However, S1 mesh had greater shrinkage, while there existed one case of infection in the S2 mesh group because of mesh folding.

Laparoscopic Totally Extraperitoneal Repair in a Pediatric Patient for Recurrent Inguinal Hernia

Abstract Introduction: Laparoscopic totally extraperitoneal (TEP) inguinal hernia repairs are common in adults but have not previously been reported in the pediatric population. This video, with a run time of 4 minutes 46 seconds, demonstrates an effective laparoscopic TEP repair in a 10-year-old boy presenting with a recurrent left inguinal hernia after three previous failed anterior repairs, including prior synthetic absorbable mesh placement. Methods: Given the likelihood of significant scarring and possible inguinal floor weakness, an anterior approach was felt to carry a high risk of injury in this patient. We decided to perform a laparoscopic TEP repair to minimize the chance of damage to cord structures with lightweight polypropylene mesh placement to reinforce the repair. Results: Access to the extraperitoneal space is obtained through a 10-mm infraumbilical incision in standard manner; two 5-mm ports are placed lateral to midline to increase the working space in a smaller body habitus. Blunt diss...

Structural Foamed Concrete with Lightweight Aggregate and Polypropylene Fiber: Product Design through Orthogonal Tests

In order to optimize the mix ratio design for structural foamed concrete with lightweight aggregate (LWA) and polypropylene fiber, orthogonal test approach with an L32 (49) orthogonal array have been carried out, with nine factors (fly ash, perlite, foam, water, waterproof agent, antifreeze, polypropylene fiber, water reducing agent and accelerating agent) and four levels for each factor. Seven responses (quality of sample molding, distribution of fibers, dry density, water absorption, compression strength, tensile splitting strength and the ratio of tensile splitting strength to compression strength) of each formula have been measured. According to the analysis of test results, an optimal mix ratio of foamed concrete with the desired engineering properties is obtained.

Quality-of-life scores in laparoscopic preperitoneal inguinal hernia repair.

Published support exists for using lightweight polypropylene mesh (PPM) to repair inguinal hernias with increased biocompatibility and decreased foreign body reaction and pain. However, quality of life (QOL) has not been assessed. We assess QOL in patients undergoing laparoscopic totally extraperitoneal hernia repair (TEP) with lightweight PPM. We performed an IRB-approved study of patients undergoing TEP hernia repair. Demographic information and hernia characteristics were collected perioperatively. Baseline Short Form-36 (SF-36), Carolinas Comfort Scale (CCS), and visual analog scale (VAS) for pain were performed preoperatively, and then after 1, 26, and 52weeks. Forty-eight patients undergoing TEP with mesh were selected. Average age was 43.2years (SD=13.2), and average BMI was 26.1kg/m(2) (SD=4.3). Procedures include bilateral hernia, right inguinal hernia, and left inguinal hernia repairs. Mean scores on the CCS(®) and VAS were low during the immediate post-op period and 1year. SF-36 mean scores for body pain, physical function, and role physical showed decreases at the postoperative survey and then subsequent increases. Pain-associated scores increased during the immediate post-op period. CCS and SF-36 scores demonstrated improvement after 1year. There was no significant difference in VAS. Bilateral repair patients reported more pain and reduced physical function versus unilateral repairs. Patients with larger mesh reported greater pain scores and reduced physical function scores. Laparoscopic inguinal hernia repair is associated with initial declines in QOL in the postoperative period. Improvements appear in the long term. General health does not appear to be impacted by laparoscopic TEP. Smaller mesh and unilateral repairs are associated with improved QOL following laparoscopic TEP with PPM. Multiple metrics for QOL are required to reflect patient recovery.

Prophylactic mesh placement to prevent parastomal hernia, early results of a prospective multicentre randomized trial

Parastomal hernia (PSH) is a common complication after colostomy formation. Recent studies indicate that mesh implantation during formation of a colostomy might prevent a PSH. To determine if placement of a retromuscular mesh at the colostomy site is a feasible, safe and effective procedure in preventing a parastomal hernia, we performed a multicentre randomized controlled trial in 11 large teaching hospitals and three university centres in The Netherlands. Augmentation of the abdominal wall with a retromuscular light-weight polypropylene mesh (Parietene Light™, Covidien) around the trephine was compared with traditional colostomy formation. Patients undergoing elective open formation of a permanent end-colostomy were eligible. 150 patients were randomized between 2010 and 2012. Primary endpoint of the PREVENT trial is the incidence of parastomal hernia. Secondary endpoints are morbidity, pain, quality of life, mortality and cost-effectiveness. This article focussed on the early results of the PREVENT trial and, therefore, operation time, postoperative morbidity, pain, and quality of life were measured. Outcomes represent results after 3months of follow-up. A total of 150 patients were randomized. Mean operation time of the mesh group (N=72) was significantly longer than in the control group (N=78) (182.6 vs. 156.8min; P=0.018). Four (2.7%) peristomal infections occurred of which one (1.4%) in the mesh group. No infection of the mesh occurred. Most of the other infections were infections of the perineal wound, equally distributed over both groups. No statistical differences were discovered in stoma or mesh-related complications, fistula or stricture formation, pain, or quality of life. During open and elective formation of an end-colostomy, primary placement of a retromuscular light-weight polypropylene mesh for prevention of a parastomal hernia is a safe and feasible procedure. The PREVENT trial is registered at: http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2018 .

Lightweight vs Midweight Polypropylene Mesh in 948 Open Ventral Hernia Repairs (OVHR)

Lightweight vs Midweight Polypropylene Mesh in 948 Open Ventral Hernia Repairs (OVHR)

'Sandwich' technique in the treatment of large and complex incisional hernias.

Reconstruction of large, complex abdominal wall hernias is an interesting challenge. Primary closure of those hernias is often not possible. There is little agreement about the most appropriate technique or prosthetic to repair these defects, in spite the fact of the prevalence of ventral hernias. Sometimes despite being contaminated surgical fields, we are often faced to reinforce with bio-prosthetic meshes. The component separation technique (CST) is a practical option; however, recurrence rates remain unacceptably high. In an attempt to reduce recurrences, we frequently added a biologic underlay mesh and a lightweight polypropylene on-lay mesh to the traditional CST. Our objective was to determine biologic mesh practice patterns of reconstructive surgeons with regard to indications, most appropriate technique, choice of prosthetics and experience with complications in order to work those hernias out. Thirty consecutive patients who underwent abdominal wall reconstruction by means of a component separations associated with non-cross-linked porcine dermal scaffolds (NCPDS) or a synthetic tissue scaffold (STS) reinforcement between October 2009 and December 2011 were retrospectively reviewed. Analysis of demographics, indications for NCPDS or STS placement, surgical technique, complications and follow-up data were performed. They underwent a 'sandwich' procedure with a biologic underlay mesh and a lightweight polypropylene on-lay mesh added to the traditional CST. We chose NCPDS or STS underlay mesh according to the fact of the presence or absence of a contaminated field. A 'sandwich' procedure was used for abdominal wall repair in 30 patients. In all of them, NCPDS or STS was positioned using an intraperitoneal technique associated to a lightweight polypropylene on-lay mesh and the CST. At a mean follow-up time of 30.1 months, most patients had successful outcomes. Occurrences included seroma, recurrence and infection. One of our patients died from multi-organ failure unrelated to hernia repair. This study shows that complex abdominal wall defects can be successfully reconstructed using a 'sandwich' procedure with a low rate of recurrence and occurrences. Moreover, repair of large, complex abdominal wall hernias by CST augmented with a biologic underlay mesh and a lightweight polypropylene on-lay mesh results in lower recurrence rates compared with historical reports of CST alone.