Incidence and risk factors of metachronous contralateral inguinal hernia development up to 25 years after unilateral inguinal hernia repair: a single-centre retrospective cohort study.

BACKGROUND: Patients undergoing unilateral inguinal hernia repair (IHR) are at risk of metachronous contralateral inguinal hernia (MCIH) development. We evaluated incidence and risk factors of MCIH development up to 25 years after unilateral IHR to determine possible indications for concomitant prophylactic surgery of the contralateral groin at the time of primary surgery. METHODS: Patients between 18 and 70 years of age undergoing elective unilateral IHR in the University Hospital of Leuven from 1995 to 1999 were studied retrospectively using the electronic health records and prospectively via phone calls. Study aims were MCIH incidence and risk factor determination. Kaplan-Meier curves were constructed and univariable and multivariable Cox regressions were performed. RESULTS: 758 patients were included (91% male, median age 53 years). Median follow-up time was 21.75 years. The incidence of operated MCIH after 5 years was 5.6%, after 15 years 16.1%, and after 25 years 24.7%. The incidence of both operated and non-operated MCIH after 5 years was 5.9%, after 15 years 16.7%, and after 25 years 29.0%. MCIH risk increased with older age and decreased in primary right-sided IHR and higher BMI at primary surgery. CONCLUSION: The overall incidence of MCIH after 25-year follow-up is 29.0%. Potential risk factors for the development of a MCIH are primary left-sided inguinal hernia repair, lower BMI, and older age. When considering prophylactic repair, we suggest a patient-specific approach taking into account these risk factors, the surgical approach and the risk factors for chronic postoperative inguinal pain.

Gallbladder torsion: a rare cause of acute abdomen in a 12-month old child.

Background: Gallbladder torsion is a rare cause of an acute abdomen, predominantly occurring in elderly women and less frequently diagnosed in the pediatric population. The diagnosis is difficult and rarely made preoperatively. However, suspicion needs to be raised in children with acute onset of abdominal pain. Ultrasound can demonstrate different signs putting forward the diagnosis but findings are often non-specific, therefore clinical suspicion should prompt a laparoscopic exploration.Case presentation: We report a case of a 12-month old girl consulting with progressive abdominal discomfort and vomiting. Ultrasound revealed an enlarged gallbladder with thickening of the wall but without demonstrable color Doppler flow and a more horizontal orientation outside its normal anatomic fossa. Gallbladder torsion was suspected. Emergency laparoscopic exploration confirmed the diagnosis and a laparoscopic cholecystectomy was performed. The postoperative course was uneventful.Conclusions: Gallbladder torsion, although rare, should be included in the differential diagnosis of an acute abdomen in children. Early recognition is necessary for a favorable outcome. The diagnosis might be supported by ultrasound but remains difficult, which is why laparoscopic exploration should be considered when the diagnosis remains unclear.

Prevention of Incisional Hernias by Prophylactic Mesh-augmented Reinforcement of Midline Laparotomies for Abdominal Aortic Aneurysm Treatment: Five-year Follow-up of a Randomized Controlled Trial.

INTRODUCTION: The incidence of incisional hernias (IHs) after open repair of an abdominal aortic aneurysm (AAA) is high. Several randomized controlled trials have reported favorable results with the use of prophylactic mesh to prevent IHs, without increasing complications. In this analysis, we report on the results of the 60-month follow-up of the PRIMAAT trial. METHODS: In a prospective, multicenter, open-label, randomized design, patients were randomized between prophylactic retrorectus mesh reinforcement (mesh group), and primary closure of their midline laparotomy after open AAA repair (no-mesh group). This article reports on the results of clinical follow-up after 60 months. If performed, ultrasonography or computed tomography were used for the diagnosis of IHs. RESULTS: Of the 120 randomized patients, 114 were included in the intention-to-treat analysis. Thirty-three patients in the no-mesh group (33/58-56.9%) and 34 patients in the mesh group (34/56-60.7%) were evaluated after 5 years. In each treatment arm, 10 patients died between the 24-month and 60-month follow-up. The cumulative incidence of IHs in the no-mesh group was 32.9% after 24 months and 49.2% after 60 months. No IHs were diagnosed in the mesh group. In the no-mesh group, 21.7% (5/23) underwent reoperation within 5 years due to an IH. CONCLUSIONS: Prophylactic retrorectus mesh reinforcement after midline laparotomy for the treatment of AAAs safely and effectively decreases the rate of IHs. The cumulative incidence of IHs after open AAA repair, when no mesh is used, continues to increase during the first 5 years after surgery, which leads to a substantial rate of hernia repairs.

Patient Satisfaction After Inguinal Hernia Surgery: Literature Review of an Overlooked Patient-Reported Outcome Measure.

INTRODUCTION: Patient satisfaction after inguinal hernia surgery is currently underappreciated and not as well studied as other patient-reported outcome measures (PROMs) on this topic. This study aims to review the literature and summarize available data. MATERIALS AND METHODS: A literature review was conducted using Medline with focus on patient-reported satisfaction after elective, inguinal hernia surgery in adults. All inguinal hernia repair techniques were considered. Small sample sizes and short follow-up periods were excluded. The methodology and results of the remaining articles were reviewed. Due to heterogeneity of reporting between articles, only a descriptive analysis was performed. RESULTS: The available data from patient-reported outcome measures regarding satisfaction yields considerable heterogeneity and lacks validation. We found that 53% of all included studies used an asymmetrical response questionnaire. Although there is an overwhelming positive patient satisfaction, wide ranges of satisfaction were seen (78-100% more than averagely satisfied, compared to 0-15% less than averagely satisfied). The number of patients not willing to undergo inguinal hernia repair again ranges from 1-16%. CONCLUSION: Our study demonstrates that patient-reported satisfaction after inguinal hernia surgery is not uniformly surveyed and remains unvalidated. Further research on patient-reported satisfaction would benefit from the reported raw data of a standardised, validated, and symmetrical five-point Likert or 11-point NRS scale on regular intervals pre- and postoperatively.

Synthetic Versus Biological Mesh in Laparoscopic and Open Ventral Hernia Repair (LAPSIS): Results of a Multinational, Randomized, Controlled, and Double-blind Trial.

OBJECTIVE: The aim of this study was to investigate the approach (open or laparoscopic) and mesh type (synthetic or biological) in ventral hernias in a clean setting.Summary of Background Data: The level of evidence on the optimal surgical approach and type of mesh in ventral hernia repair is still low. METHODS: Patients with a ventral abdominal hernia (diameter 4-10 cm) were included in this double-blind randomized controlled trial across 17 hospitals in 10 European countries. According to a 2 × 2-factorial design, patients were allocated to 4 arms (open retromuscular or laparoscopic intraperitoneal, with synthetic or Surgisis Gold biological mesh). Patients and outcome assessors were blinded to mesh type used. Major postoperative complication rate (hernia recurrence, mesh infection, or reoperation) within 3 years after surgery, was the primary endpoint in the intention-to-treat population. RESULTS: Between September 1st, 2005, and August 7th, 2009, 253 patients were randomized and 13 excluded. Six of 61 patients (9.8%) in the open synthetic mesh arm, 15 of 66 patients (22.7%) in the open biological mesh arm, 7 of 64 patients (10.9%) in the laparoscopic synthetic mesh arm and 17 of 62 patients (27.4%) in the laparoscopic biological mesh arm had a major complication. The use of biological mesh resulted in significantly more complications (P = 0.013), also after adjusting for hernia type, body mass index, and study site. The trial was prematurely stopped due to an unacceptable high recurrence rate in the biological mesh arms. CONCLUSIONS: The use of Surgisis Gold biological mesh is not recommended for noncomplex ventral hernia repair. TRIAL REGISTRATION: This trial was registered at controlled-trials.com (ISRCTN34532248).

Observational Cohort Study on the Use of a Slowly Fully Resorbable Synthetic Mesh (Phasix™) in the Treatment of Complex Abdominal Wall Pathology with Different Grades of Contamination.

PURPOSE: Abdominal wall hernia repair in contaminated cases remains a therapeutic challenge due to the high risk of post-operative surgical site occurrences (SSO). Slowly resorbable synthetic (biosynthetic) meshes have recently been introduced and may offer unique advantages when challenged with bacterial colonization during abdominal wall reconstruction. METHODS: A multicenter single-arm retrospective observational cohort study examined all consecutive patients in whom a poly-4-hydroxybutyrate mesh (Phasix™ or Phasix™ ST; Becton Dickinson, Franklin Lakes, NJ, USA) was used for the repair of an inguinal or ventral/incisional hernia, or to replace an infected synthetic mesh. Patient records were analyzed according to the level of contamination, using the classification score of the Centers for Disease Control and Prevention (CDC). The primary objective was to evaluate short-term postoperative morbidity by assessing SSOs and the need for reoperation or even mesh excision. RESULTS: A total of 47 patients were included. The median age was 68 years (30-87), the male/female ratio was 26/21, and the median BMI was 26.5 kg/m2 (16.4-46.8). There were 17 clean cases, 17 clean-contaminated, 6 contaminated and 7 dirty. Median follow-up time was 48 days. An SSO was seen in 4 clean (23.5%), 7 clean-contaminated (41.2%), 2 contaminated (33.3%) and 5 dirty cases (71.4%). A surgical site occurrence requiring procedural intervention (SSOPI) was seen in 2 clean (11.8%), 3 clean-contaminated (17.6%), 1 contaminated (16.7%) and 2 dirty cases (28.6%). Hernia recurrence was seen in 1 clean (5.9%), 2 clean-contaminated (11.8%) and 3 dirty cases (42.9%). Mesh excision had to be performed in only one case in the contaminated group. CONCLUSION: The Phasix™ mesh shows promising short-term results when used in contaminated hernia-related surgery. Even in contaminated or dirty conditions, with or without infection of the mesh, resection of the mesh only had to be performed once and patients could be managed either conservatively or by relatively minor reoperations. However, further research is needed to fully evaluate the safety and efficacy of these meshes.

Resorbable Synthetic Meshes for Abdominal Wall Defects in Preclinical Setting: A Literature Review.

BACKGROUND: Prosthetic materials for the repair of abdominal wall defects have been studied extensively to improve outcome. A new approach can be the use of a slowly resorbable synthetic mesh, which aims to combine advantages of both synthetic and biological meshes. The objective of this review is to give an overview of the physicochemical characteristics and biomechanical, histological, and macroscopic outcome (recurrence, adhesion formation) of the use of resorbable synthetic meshes, for treatment and prevention of abdominal wall hernias, based on experimental studies. METHODS: A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Only experimental studies were included. Outcome parameters were resorption, degradation, organization of connective tissue, inflammatory response, tensile strength, and amount of adhesion formation. Surgical characteristics were taken into account as well (type of defect, clean versus contaminated model, position mesh, repair of the defect, recurrences). RESULTS: In total, eleven articles were included. Three absorbable synthetic meshes are currently available: GORE BIO-A mesh (Gore), TIGR Matrix Surgical mesh (Novus Scientific), and Phasix mesh (Bard). Two studies concluded that, despite an early transient inflammatory reaction in the first months, remodeling was good in GORE BIO-A, 6-12 mo after augmentation or suture line reinforcement with only minimal to moderate adhesions when used intraperitoneally. The TIGR Matrix Surgical mesh shows only partial remodeling with a persistent foreign body reaction after 1 y. Phasix mesh seems to perform well in extraperitoneal implantation after 1 y in two studies, although the defect was small. Only two studies directly compared two resorbable synthetic meshes under the same circumstances. The latter also included a number of animals where the meshes were used in a contaminated nonhernia model. No hernia recurrences or deaths of animals were described in all studies. CONCLUSIONS: The use of resorbable synthetic meshes in the prevention or treatment of abdominal wall defects in animal experiments with small defects in clean setting seems safe, with no serious complications related to the device during short-term follow-up. However, there is no evidence available that can support the advantages of resorbable synthetic meshes over the use of synthetic or biological meshes, mostly due to lack of good data. More experimental studies are needed, followed by randomized controlled trials and prospective registries in humans with a sufficiently long follow-up period, to reveal the potential advantages in clinical practice.

What do pediatric surgeons think about sexual issues in dealing with patients with anorectal malformations? The ARM-Net consortium members' opinion.

PURPOSE: Since pediatric surgeons aim to follow their patients with anorectal malformations (ARM) into adulthood the aim of this study was to investigate how pediatric surgeons deal with sexual issues related to ARM. METHODS: In 2018, a questionnaire was developed by the working group "Follow-up and sexuality" of the ARM-Net consortium and sent to all consortium-linked pediatric surgeons from 31 European pediatric surgical centers. Obtained data were statistically analyzed. RESULTS: Twenty-eight of 37 pediatric surgeons (18 males/10 females) answered the questionnaire. The majority of pediatric surgeons (82%) think they should talk about sexual issues with their patient. More than 50% of pediatric surgeons do not feel at all or only moderately confident discussing the topic of sexuality. Most pediatric surgeons require more support (96%) and wish to be trained in sexuality and sexual issues (78%) to feel confident towards their ARM-patients/parents. For optimal care, sexual issues with ARM-patients should be managed by a multidisciplinary team. CONCLUSIONS: Pediatric surgeons feel that sexuality is an important issue for their ARM-patients, which they are primarily responsible of but should be managed in concert with a multidisciplinary team. A training in sexuality is wished to feel more confident about this specific issue.

Pericardio-Amniotic Shunting for Incomplete Pentalogy of Cantrell.

A 27-year-old woman, gravida 2, para 0, presented with an incomplete Pentalogy of Cantrell with an omphalocele, diaphragmatic hernia, and a pericardial defect at 32 weeks' gestation. A large pericardial effusion compressed the lungs and had led to a reduced lung growth with an observed-to-expected total lung volume of 28% as measured by MRI. The effusion disappeared completely after the insertion of a pericardio-amniotic shunt at 33 weeks. After birth, the newborn showed no signs of pulmonary hypoplasia and underwent a surgical correction of the defect. Protracted wound healing and a difficult withdrawal from opioids complicated the neonatal period. The child was discharged on postnatal day 105 in good condition. This case demonstrates that in case of Pentalogy of Cantrell with large pericardial effusion, the perinatal outcome might be improved by pericardio-amniotic shunting.

Prevention of Incisional Hernias by Prophylactic Mesh-augmented Reinforcement of Midline Laparotomies for Abdominal Aortic Aneurysm Treatment: A Randomized Controlled Trial.

BACKGROUND: The incidence of incisional hernias after abdominal aortic aneurysm repair is high. Prophylactic mesh-augmented reinforcement during laparotomy closure has been proposed in patients at high risk of incisional hernia. METHODS: A multicenter randomized trial was conducted on patients undergoing elective abdominal aortic aneurysm repair through a midline laparotomy (Clinical.Trials.gov: NCT00757133). In the study group, retromuscular mesh-augmented reinforcement was performed with a large-pore polypropylene mesh (Ultrapro, width 7.5 cm). The primary endpoint was the incidence of incisional hernias at 2-year follow-up. RESULTS: Between February 2009 and January 2013, 120 patients were recruited at 8 Belgian centers. Patients' characteristics at baseline were similar between groups. Operative and postoperative characteristics showed no difference in morbidity or mortality. The cumulative incidence of incisional hernias at 2-year follow-up after conventional closure was 28% (95% confidence interval [CI], 17%-41%) versus 0% (95% CI, 0%-6%) after mesh-augmented reinforcement (P < 0.0001; Fisher exact test). The estimated "freedom of incisional hernia" curves (Kaplan-Meier estimate) were significantly different across study arms (χ = 19.5, P < 0.0001; Mantel-Cox test). No adverse effect related to mesh-augmented reinforcement was observed, apart from an increased mean time to close the abdominal wall for mesh-augmented reinforcement compared with the control group: 46 minutes (SD, 18.6) versus 30 minutes (SD, 18.5), respectively (P < 0.001; Mann-Whitney U test). CONCLUSIONS: Prophylactic retromuscular mesh-augmented reinforcement of a midline laparotomy in patients with abdominal aortic aneurysm is safe and effectively prevents the development of incisional hernia during 2 years, with an additional mean operative time of 16 minutes.

Microvillus inclusion disease: a subtotal enterectomy as a bridge to transplantation.

BACKGROUND: Microvillus inclusion disease (MVID) is a known congenital cause of intractable diarrhea resulting in permanent intestinal failure. There is need for a lifelong total parenteral nutrition (TPN) from diagnosis and the prognosis is poor. Most patients die by the second decade of life as a result of complications of parenteral alimentation including liver failure or sepsis. The only available treatment at this moment is a small bowel transplantation. But before that moment, the patients often suffer from a persistent failure to thrive and electrolyte disturbances despite continuous TPN. METHODS AND RESULTS: We report what we believe is a first case of an extensive small bowel resection in a 5-month-old boy with proven MVID to act as a bridge to (liver-) intestinal transplantation to treat failure to thrive and intractable diarrhea. CONCLUSIONS: An extensive small bowel resection can be done to enhance the chance of survival leading up to the transplantation by managing fluid and electrolyte imbalance. It facilitates medical management of these patients and makes a bowel transplantation possible at a later stage.

Expression of intestinal drug transporter proteins and metabolic enzymes in neonatal and pediatric patients.

The development of pediatric oral drugs is hampered by a lack of predictive simulation tools. These tools, in turn, require data on the physiological variables that influence oral drug absorption, including the expression of drug transporter proteins (DTPs) and drug-metabolizing enzymes (DMEs) in the intestinal tract. The expression of hepatic DTPs and DMEs shows age-related changes, but there are few data on protein levels in the intestine of children. In this study, tissue was collected from different regions of the small and large intestine from neonates (i.e., surgically removed tissue) and from pediatric patients (i.e., gastroscopic duodenal biopsies). The protein expression of clinically relevant DTPs and DMEs was determined using a targeted mass spectrometry approach. The regional distribution of DTPs and DMEs was similar to adults. Most DTPs, with the exception of MRP3, MCT1, and OCT3, and all DMEs showed the highest protein expression in the proximal small intestine. Several proteins (i.e., P-gp, ASBT, CYP3A4, CYP3A5, CYP2C9, CYP2C19, and UGT1A1) showed an increase with age. Such increase appeared to be even more pronounced for DMEs. This exploratory study highlights the developmental changes in DTPs and DMEs in the intestinal tract of the pediatric population. Additional evaluation of protein function in this population would elucidate the implications of the presented changes in protein expression on absorption of orally administered drugs in neonates and pediatric patients.

European reference network for rare inherited congenital anomalies (ERNICA) evidence based guideline on the management of gastroschisis.

BACKGROUND: The European Reference Network for rare Inherited Congenital Anomalies, ERNICA, guidelines for gastroschisis cover perinatal period to help teams to improve care. METHOD: A systematic literature search including 136 publications was conducted. Research findings were assessed following the GRADE methodology. The evidence to decision framework was used to determine the strength and direction of recommendations. RESULTS: The mode or timing of delivery do not impact neonatal mortality, risk of NEC or time on parenteral nutrition (PN). Intra or extra abdominal bowel dilatation predict complex gastroschisis and longer length of hospital stay but not increased perinatal mortality. Outcomes after Bianchi procedure and primary fascia closure under anesthesia are similar. Sutureless closure decreases the rate of surgical site infections and duration of ventilation compared to surgical closure. Silo-staged closure with or without intubation results in similar outcomes. Outcomes of complex gastroschisis (CG) undergoing early or delayed surgical repair are similar. Early enteral feeds starting within 14 days is associated with lower risk of surgical site infection. RECOMMENDATIONS: The panel suggests vaginal birth between 37 and 39 w in cases of uncomplicated gastroschisis. Bianchi's approach is an option in simple gastroschisis. Sutureless closure is suggested when general anesthesia can be avoided, sutured closure. If anesthesia is required. Silo treatment without ventilation and general anesthesia can be considered. In CG with atresia primary intestinal repair can be attempted if the condition of patient and intestine allows. Enteral feeds for simple gastroschisis should start within 14 days.

Ernica Clinical Consensus Statements on Total Colonic and Intestinal Aganglionosis.

BACKGROUND: Hirschsprung disease is a congenital intestinal motility disorder characterized by an absence of enteric ganglion cells. Total colonic aganglionosis and near total or total intestinal aganglionosis, defined as absence of ganglion cells in the entire colon and with variable length of small bowel involved, are life-threatening conditions which affect less than 10 % of all patients with Hirschsprung disease. The aim of this project was to develop clinical consensus statements within ERNICA, the European Reference Network for rare congenital digestive diseases, on four major topics: Surgical treatment of total colonic aganglionosis, surgical treatment of total intestinal aganglionosis, management of poor bowel function in total colonic and/or intestinal aganglionosis and long-term management in total colonic and or intestinal aganglionosis. METHODS: A multidisciplinary panel of representatives from ERNICA centers was invited to participate. Literature was searched, using specified search terms, in Medline (ALL), Embase and Google Scholar. Abstracts were screened and full text publications were selected. The panel was divided in four groups that extracted data from the full text publications and suggested draft statements for each of the major topics. A modified Delphi process was used to refine and agree on the statements. RESULTS: The consensus statement was conducted by a multidisciplinary panel of 24 participants from 10 European countries, 45 statements reached consensus after 3 Delphi-rounds. The availability of high-quality clinical evidence was limited, and most statements were based on expert opinion. Another 25 statements did not reach consensus. CONCLUSIONS: Total colonic and total intestinal aganglionosis are rare variants of Hirschsprung disease, with very limited availability of high-quality clinical evidence. This consensus statement provides statements on the surgical treatment, management of poor bowel function and long-term management for these rare patients. The expert panel agreed that patients benefit from multidisciplinary and personalized care, preferably in an expert center. TYPE OF STUDY: Clinical consensus statement. LEVEL OF EVIDENCE: 3a.

One-year outcome of biological and synthetic bioabsorbable meshes for augmentation of large abdominal wall defects in a rabbit model.

BACKGROUND: Long-term efficacy of biological and synthetic bioabsorbable meshes for large hernia repair is currently unclear. This rabbit study is aimed at investigating 1-y outcome of biological and synthetic bioabsorbable meshes for augmentation of large abdominal wall defects. MATERIALS AND METHODS: In 46 rabbits, an 11 × 4 cm, full-thickness abdominal wall defect was repaired primarily, or with cross-linked (Permacol, Collamend) or non-cross-linked (Surgisis 4-ply, Surgisis Biodesign) biological, synthetic bioabsorbable (GORE BIO-A Tissue Reinforcement [TR], TIGR Matrix Surgical Mesh [MSM]), or polypropylene (Bard Mesh) meshes, using the underlay augmentation technique. One year after surgery, primary outcome was recurrence; secondary outcomes were tensile strength, histologic degree of tissue remodeling, and intraabdominal adhesion formation. RESULTS: Only two Surgisis 4-ply animals (50%) presented with a recurrent hernia. All GORE BIO-A TR meshes were completely resorbed and, as after primary repair, well-organized connective tissue without inflammation was present, with moderate adhesion formation and sufficient tensile strength. Cross-linked biological and TIGR MSM meshes demonstrated highest tensile strength but were only partially incorporated, with similar foreign body reaction and adhesion formation as polypropylene meshes in the TIGR MSM group, and minimal degradation and moderate adhesion formation in the cross-linked biological group. In the non-cross-linked biological group sufficient tensile strength and moderate adhesion formation were found, with pronounced inflammation if mesh remnants were present. CONCLUSIONS: Synthetic bioabsorbable GORE BIO-A TR meshes were associated with optimal tissue remodeling, with complete resorption, presence of well-organized tissue, and no inflammation. However, mesh augmentation had no advantages regarding recurrence rate versus primary repair of large abdominal wall defects.

Maintenance training for laparoscopic suturing: the quest for the perfect timing and training model: a randomized trial.

BACKGROUND: Although excellent training programs exist for acquiring the challenging skill required in laparoscopic suturing, without subsequent reinforcement, performance is prone to decay. Therefore, maintenance training is proposed to ensure better skill retention. This study aimed to elucidate the ideal timing and frequency of maintenance training as well as the best model to be used for this training. METHODS: After completing a proficiency-based laparoscopic suturing training, 39 medical students attended different maintenance programs represented by four groups: a control group without additional training (group 1), a massed training group with one supervised training session (150 min) after 2.5 months (group 2), and two distributed training groups with five monthly unsupervised training sessions of 30 min on a box trainer (group 3) or the LapMentor(®) (group 4). Retention testing, after 5 months, included suturing on a box trainer and on a cadaver porcine Nissen model. Performance scores (time and errors) were expressed in seconds. Afterward, time needed to regain proficiency was measured. RESULTS: On the box trainer, the median performance scores were 233 s (interquartile range [IQR] 27 s) for group 1, 180 s (IQR 55 s) for group 2, 169 s (IQR 26 s) for group 3, and 226 s (IQR 66 s) for group 4 (p = 0.03). No difference was seen between groups 2 and 3, both of which significantly outperformed groups 1 and 4. On the porcine Nissen model, no differences were detected between the groups (p = 0.53). Group 3 reached proficiency more quickly than the other groups. CONCLUSIONS: Maintenance training is a valuable and necessary addendum to proficiency-based training programs for laparoscopic suturing. A maintenance-training interval of 1 month with unsupervised training sessions on simple box trainers seems ideal. The LapMentor(®) did not show any benefit. Performance differences between groups did not translate to a clinically relevant model, indicating that transfer of training is not perfect.

Effect of Degradation in Small Intestinal Fluids on Mechanical Properties of Polycaprolactone and Poly-l-lactide-co-caprolactone.

Polycaprolactone and poly-l-lactide-co-caprolactone are promising degradable biomaterials for many medical applications. Their mechanical properties, especially a low elastic modulus, make them particularly interesting for implantable devices and scaffolds that target soft tissues like the small intestine. However, the specific environment and mechanical loading in the intestinal lumen pose harsh boundary conditions on the design of these devices, and little is known about the degradation of those mechanical properties in small intestinal fluids. Here, we perform tensile tests on injection molded samples of both polymers during in vitro degradation of up to 70 days in human intestinal fluids. We report on yield stress, Young's modulus, elongation at break and viscoelastic parameters describing both materials at regular time steps during the degradation. These characteristics are bench-marked against degradation studies of the same materials in other media. As a result, we offer time dependent mechanical properties that can be readily used for the development of medical devices that operate in the small intestine.