Outcomes of a new slowly resorbable biosynthetic mesh (Phasix™) in potentially contaminated incisional hernias: A prospective, multi-center, single-arm trial.

BACKGROUND: Resorbable biomaterials have been developed to reduce the amount of foreign material remaining in the body after hernia repair over the long-term. However, on the short-term, these resorbable materials should render acceptable results with regard to complications, infections, and reoperations to be considered for repair. Additionally, the rate of resorption should not be any faster than collagen deposition and maturation; leading to early hernia recurrence. Therefore, the objective of this study was to collect data on the short-term performance of a new resorbable biosynthetic mesh (Phasix™) in patients requiring Ventral Hernia Working Group (VHWG) Grade 3 midline incisional hernia repair. MATERIALS AND METHODS: A prospective, multi-center, single-arm trial was conducted at surgical departments in 15 hospitals across Europe. Patients aged ≥18, scheduled to undergo elective Ventral Hernia Working Group Grade 3 hernia repair of a hernia larger than 10 cm2 were included. Hernia repair was performed with Phasix™ Mesh in sublay position when achievable. The primary outcome was the rate of surgical site occurrence (SSO), including infections, that required intervention until 3 months after repair. RESULTS: In total, 84 patients were treated with Phasix™ Mesh. Twenty-two patients (26.2%) developed 32 surgical site occurrences. These included 11 surgical site infections, 9 wound dehiscences, 7 seromas, 2 hematomas, 2 skin necroses, and 1 fistula. No significant differences in surgical site occurrence development were found between groups repaired with or without component separation technique, and between clean-contaminated or contaminated wound sites. At three months, there were no hernia recurrences. CONCLUSION: Phasix™ Mesh demonstrated acceptable postoperative surgical site occurrence rates in patients with a Ventral Hernia Working Group Grade 3 hernia. Longer follow-up is needed to evaluate the recurrence rate and the effects on quality of life. This study is ongoing through 24 months of follow-up.

Comparison of different modalities for the diagnosis of parastomal hernia: a systematic review.

PURPOSE: Parastomal hernia (PSH) is a common complication following stoma formation. The incidence of PSH varies widely due to several factors including differences in diagnostic modality, observer, definition, and classification used for diagnosing PSH. The aim of this systematic review was to evaluate the diagnostic accuracy of the modalities used to identify PSH. METHODS: Embase, MEDLINE, Cochrane, Web of Science, and Google Scholar databases were searched. Studies reporting PSH incidence rates detected by two or more different diagnostic modalities or inter-observer variation on one diagnostic modality were included. Article selection and assessment of study quality were conducted independently by two researchers using Cochrane Collaboration's tool for assessing risk of bias. PROSPERO registration: CRD42018112732. RESULTS: Twenty-nine studies (n = 2514 patients) were included. Nineteen studies compared CT to clinical examination with relative difference in incidence rates ranging from 0.64 to 3.0 (n = 1369). Overall, 79% of studies found an increase in incidence rate when using CT. Disagreement between CT and clinical examination ranged between 0 and 37.3% with pooled inter-modality agreement Kappa value of 0.64 (95% CI 0.52-0.77). Four studies investigated the diagnostic accuracy of ultrasonography (n = 103). Compared with peroperative diagnosis, CT and ultrasonography both seemed accurate imaging modalities with a sensitivity of 83%. CONCLUSION: CT is an accurate diagnostic modality for PSH diagnosis and increases PSH detection rates, as compared with clinical examination. Studies that specially focus on the diagnostic accuracy are needed and should aim to take patient-reported outcomes into account. A detailed description of the diagnostic approach, modality, definition, and involved observers is prerequisite for future PSH research.

Zinc-Impregnated Mesh for Abdominal Wall Repair Reduces Infection in a Rat Model of Peritonitis.

BACKGROUND: The objective of this study was to assess whether a zinc-impregnated polypropylene mesh (ZnMesh) has better antibacterial properties in a contaminated environment compared with a regular polypropylene mesh. MATERIALS AND METHODS: Thirty-eight Wistar Han rats underwent cecal ligation and puncture to induce peritonitis 24 h before implantation of an intraperitoneal ZnMesh or a regular polypropylene mesh. Primary outcome was the number of colony forming units (CFU) per sample (mesh and abdominal wall). Secondary outcomes were macroscopic (incorporation of mesh, abscesses, and adhesions on mesh surface) and histological (inflammatory cell reaction, mesh-specific parameters, and collagen deposition) parameters. All outcomes were evaluated after 30 and 90 d. RESULTS: After 30 d, no significant difference in CFU per sample was present between the ZnMesh and control groups. After 90 d, a lower number of CFU per sample was present in the ZnMesh group compared with the control group (trypticase soy agar with 5% sheep blood: 0 log10 CFU/sample IQR: 0-1.40 versus 1.58 log10 CFU/sample IQR: 0-4.30, P = 0.012; MacConkey: 0 log10 CFU/sample IQR: 0-2.65 versus 1.18 log10 CFU/sample IQR: 0-4.04, P = 0.438). After 90 d, the percentage of adhesions on mesh surface was significantly higher in the ZnMesh group (95% IQR: 60%-100% versus 50% IQR: 23%-75%, P = 0.029). No differences were seen in other macroscopic outcomes or histology. CONCLUSIONS: A significantly lower number of CFU per sample was found in the ZnMesh group after 90 d. After 30 d, no statistically significant differences in CFU per sample were seen. This result suggests that the ZnMesh group has better antibacterial properties in a contaminated environment. However, this is at the cost of a significantly higher percentage of adhesions.

Risk Factors for Incarceration in Patients with Primary Abdominal Wall and Incisional Hernias: A Prospective Study in 4472 Patients.

BACKGROUND: Incarceration of primary and incisional hernias often results in emergency surgery. The objective of this study was to evaluate the relation of defect size and location with incarceration. Secondary objectives comprised identification of additional patient factors associated with an incarcerated hernia. METHODS: A registry-based prospective study was performed of all consecutive patients undergoing hernia surgery between September 2011 and February 2016. Multivariate logistic regression was performed to identify risk factors for incarceration. RESULTS: In total, 83 (3.5%) of 2352 primary hernias and 79 (3.7%) of 2120 incisional hernias had a non-reducible incarceration. For primary hernias, a defect width of 3-4 cm compared to defects of 0-1 cm was significantly associated with an incarcerated hernia (OR 2.85, 95% CI 1.57-5.18, p = 0.0006). For incisional hernias, a defect width of 3-4 cm compared to defects of 0-2 cm was significantly associated with an incarceration (OR 2.14, 95% CI 1.07-4.31, p = 0.0324). For primary hernias, defects in the peri- and infra-umbilical region portrayed a significantly increased odds for incarceration as compared to supra-umbilical defects (OR 1.98, 95% CI 1.02-3.85, p = 0.043). Additionally, in primary hernias age, BMI, and constipation were associated with incarceration. In incisional hernias age, BMI, female sex, diabetes mellitus and ASA classification were associated with incarceration. CONCLUSION: For primary and incisional hernias, mainly defects of 3-4 cm were associated with incarceration. For primary hernias, mainly defects located in the peri- and infra-umbilical region were associated with incarceration. Based on patient and hernia characteristics, patients with increased odds for incarceration may be selected and these patients may benefit from elective surgical treatment.

Anatomical study comparing medialization after Rives-Stoppa, anterior component separation, and posterior component separation.

BACKGROUND: Large incisional hernias require medialization of the rectus abdominis muscles to facilitate tension-free closure. Medialization may be achieved by Rives-Stoppa, anterior component separation, or posterior component separation. This study aims to compare medialization achieved by these techniques in postmortem human specimens. METHODS: First, the Rives-Stoppa procedure was performed. Subsequently, anterior and posterior component separation were performed on one side in each specimen, with each specimen functioning as its own control. Medialization was measured at three levels of the linea alba with three 1-kg weights. Both medialization obtained in addition to initial medialization after opening the linea alba and total medialization were measured. Results are presented as median and interquartile range. RESULTS: A total of 13 postmortem human specimens were included (Rives-Stoppa n = 13, component separation n = 10). Additional medialization after Rives-Stoppa was 1.2 cm (IQR: 0.3-2.2) for the anterior rectus sheath and 2.2 cm (IQR: 1.6-3.0) for the posterior rectus sheath (total medialization: 3.9 and 4.5 cm). For the anterior rectus sheath, additional medialization was 2.6 cm (IQR: 1.2-3.6) after anterior component separation and 1.9 cm (IQR: 0.4-3.4) after posterior component separation (P = .125, total medialization: 6.5 and 5.7 cm). For the posterior rectus sheath, additional medialization was 3.0 cm (IQR: 2.2-3.7) after anterior component separation and 5.2 cm (IQR: 4.2-5.9) after posterior component separation (P < .001, total medialization: 5.8 and 9.4 cm). CONCLUSION: Posterior component separation yielded significantly more medialization of the posterior rectus sheath compared with Rives-Stoppa and anterior component separation. Anterior component separation may provide marginally more medialization of the anterior rectus sheath.

Primary and incisional ventral hernias are different in terms of patient characteristics and postoperative complications - A prospective cohort study of 4,565 patients.

BACKGROUND: Primary and incisional hernias are often pooled in publications studying hernia symptoms, treatment, or surgical outcomes. The question rises whether this is justified or if primary and incisional hernia should be considered as two separate entities. The aim of this prospective cohort study is to compare primary and incisional ventral hernias regarding patient characteristics, hernia characteristics, surgical characteristics, and postoperative complications. MATERIALS AND METHODS: A registry-based, prospective cohort study was performed. All patients undergoing primary or incisional hernia repair surgery between September 1st, 2011 and February 29th, 2016 were included. Patient baseline characteristics, hernia characteristics, surgical characteristics, and postoperative outcomes were collected and analyzed. RESULTS: A total of 4565 patients were included, of whom 2374 had a primary hernia and 2191 had an incisional hernia. All patient, hernia, and surgical characteristics were statistically significantly different between primary and incisional hernias except for corticosteroid use, history of inguinal hernia, incarceration, and emergency surgery. Overall complication rates (wound, surgical, and medical) were significantly different (105/2374 (4.4%) for primary hernia versus 323/2191 (15%) for incisional hernia, p < 0.001). CONCLUSION: Primary and incisional hernia are statistically significantly different for almost all patient, hernia, surgical, and postoperative characteristics analyzed. Given these differences, data on primary hernias and incisional hernias should not be pooled in studies reporting on hernia repair.

External Validation of the European Hernia Society Classification for Postoperative Complications after Incisional Hernia Repair: A Cohort Study of 2,191 Patients.

BACKGROUND: Incisional hernia is a frequent complication after midline laparotomy. Surgical hernia repair is associated with complications, but no clear predictive risk factors have been identified. The European Hernia Society (EHS) classification offers a structured framework to describe hernias and to analyze postoperative complications. Because of its structured nature, it might prove to be useful for preoperative patient or treatment classification. The objective of this study was to investigate the EHS classification as a predictor for postoperative complications after incisional hernia surgery. STUDY DESIGN: An analysis was performed using a registry-based, large-scale, prospective cohort study, including all patients undergoing incisional hernia surgery between September 1, 2011 and February 29, 2016. Univariate analyses and multivariable logistic regression analysis were performed to identify risk factors for postoperative complications. RESULTS: A total of 2,191 patients were included, of whom 323 (15%) had 1 or more complications. Factors associated with complications in univariate analyses (p < 0.20) and clinically relevant factors were included in the multivariable analysis. In the multivariable analysis, EHS width class, incarceration, open surgery, duration of surgery, Altemeier wound class, and therapeutic antibiotic treatment were independent risk factors for postoperative complications. Third recurrence and emergency surgery were associated with fewer complications. CONCLUSIONS: Incisional hernia repair is associated with a 15% complication rate. The EHS width classification is associated with postoperative complications. To identify patients at risk for complications, the EHS classification is useful.

Oxygen therapies and their effects on wound healing.

Oxygen is an important factor for wound healing. Although several different therapies investigated the use of oxygen to aid wound healing, the results of these studies are not unequivocal. This systematic review summarizes the clinical and experimental studies regarding different oxygen therapies for promoting wound healing, and evaluates the outcomes according the methodological details. A systematic literature search was conducted using Embase, Medline, Web of Science, Cochrane, PubMed publisher, and Google Scholar libraries. Clinical and experimental studies investigating oxygen for wound healing were selected. Included articles were categorized according to the kind of therapy, study design, and wound type. The methodological details were extracted and analyzed. Sixty-five articles were identified and divided in three different oxygen therapies: Local oxygen therapy, hyperbaric oxygen therapy, and supplemental inspired oxygen therapy. More than half of the included local oxygen and hyperbaric oxygen studies had one or more significant positive outcomes, 77 and 63%, respectively. Supplemental inspired oxygen therapy during gastrointestinal and vascular surgery was more likely to have a positive result than during other surgical interventions reducing surgical site infections. These many positive outcomes promote the use of oxygen treatment in the stimulation of wound healing. However, the lack of clinical studies and vast methodological diversity made it impossible to perform a proper comparison within and between the different therapies. Further randomized clinical studies are warranted to examine the value of these therapies, especially studies that investigate the more patient-friendly oxygen dressings and topical wound oxygen therapies. Also, to achieve more solid and consistent data, studies should use more standardized methods and subjects.

Long term results of open complex abdominal wall hernia repair with self-gripping mesh: A retrospective cohort study.

BACKGROUND: In case of complex ventral hernias, Rives-Stoppa and component separation technique are considered as favourable treatment techniques. However, mesh-related complications like recurrence, infection and chronic pain are still a common problem after mesh repair. Previous studies have reported promising results of the use of a self-gripping mesh (ProGrip™) in incisional hernia repair. This study aimed to evaluate the long term results of this mesh for complex ventral hernia treatment. MATERIALS AND METHODS: Patients with complex ventral hernia undergoing repair between June 2012 and June 2015, using the ProGrip™-mesh in retromuscular position, were included. All patients visited the outpatient clinic to evaluate short term complications and recurrence. After at least one year, telephone interviews were conducted to evaluate long term results. RESULTS: A total of 46 patients (median age 59 years) were included. 40 patients (87%) were diagnosed with incisional hernia. Seven patients (18%) had incisional hernia combined with another hernia. Four patients (8.7%) had an umbilical hernia, one patient (2.2%) had an epigastric hernia and one patient (2.2%) had rectus diastasis. 39 patients completed follow-up. Median follow-up was 25 months (IQR: 19-35 months). 28 patients (72%) did not report any complaints. Nine patients reported pain (average VAS of 1.7). Two patients developed a recurrence requiring reoperation. One patient developed mesh infection requiring reoperation. CONCLUSION: Long term results of the use of a self-gripping mesh for complex abdominal wall hernias show a low recurrence rate, even in complex hernia cases. This makes the mesh a good choice in this difficult patient group.

Clinical, mechanical, and immunohistopathological effects of tissue adhesives on the colon: An in-vivo study.

BACKGROUND: Tissue adhesives may be useful for sealing bowel anastomoses by preventing anastomotic leakage. Prior to clinical implementation, an in-depth analysis of the clinical and immunohistopathological effects of tissue adhesives on the target tissue and of the mechanical strength of the adhesive bond in an in vivo model is needed. MATERIALS AND METHODS: In 84 rats, two bowel segments were glued using one of the following tissue adhesive: Bioglue, Gelatin-resorcinol-formaldehyde (GRF), Glubran 2, Histoacryl Flex, Omnex, Duraseal Xact, or Tissucol. Rats were followed for 7 or 28 days. Endpoints were clinical complication rate, mechanical strength, and immunohistopathological reactions. RESULTS: Of the seven tissue adhesives, GRF and Bioglue showed the highest rates of bowel wall destruction and ileus and the most severe immunohistopathological tissue reactions at 7 and 28 days. Cyanoacrylates (Histoacryl Flex, Omnex, Glubran 2) showed high mechanical strength and mild immunohistopathological reactions at 7 and 28 days. Duraseal Xact and Tissucol were the most inert tissue adhesives, but exhibited low mechanical strength. At 28 days, mechanical strength was significantly correlated to CD8, CD68, and Ki67 cell counts. CONCLUSION: Based on the clinical and immunohistopathological outcomes, GRF and Bioglue were found to be the least suitable tissue adhesives for colonic use. Duraseal Xact and Tissucol were inert but also showed low mechanical strength. Cyanoacrylates exhibited mild clinical and immunohistopathological effects while maintaining high strength, which makes them promising as colonic sealants. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 846-854, 2017.

Sutureless closure of colonic defects with tissue adhesives: an in vivo study in the rat.

BACKGROUND: Tissue adhesives (TAs) in gastrointestinal surgery are gradually gaining acceptance. Before implementation as colonic sealants, an evaluation of the sealing capability of a TA when in contact with fecal matter, as in a leaking anastomosis, is needed. In this study, we used clinically available TAs for the sutureless closure of colonic defects evaluating mechanical strength and tissue healing. METHODS: A total of 160 rats were divided into 8 groups. Two .5-cm incisions were created, one in the proximal and another in the distal colon. Incisions were sealed with a TA: Histoacryl Flex, Bioglue, Dermabond, Tissucol, Duraseal Xact, gelatin-resorcinol-formaldehyde or Glubran 2. A control group was included in which the colonic defects were not sealed. Follow-up time was 3 or 10 days. Clinical complication rate, bursting pressure, and histopathologic analysis was included. RESULTS: Leakage rates in the TA groups were highest for Duraseal Xact, Bioglue, and gelatin-resorcinol-formaldehyde at 3 and 10 days. The cyanoacrylates Glubran 2, Histoacryl Flex, and Omnex, and the fibrin glue Tissucol showed the lowest overall clinical complication rates while maintaining the highest bursting pressure at day 10. Histoacryl Flex exhibited significantly higher collagen formation at day 10 than the other TAs. CONCLUSIONS: This experimental model evaluates the protective effect of a TA seal on a leaking colonic defect. We found large differences in leakage rates and inertness of the tested TAs. The cyanoacrylates Histoacryl Flex, Omnex, and Glubran 2 as well as the fibrin glue Tissucol demonstrated the lowest leakage rates and the most inert histopathologic profile while maintaining high mechanical strength.

Systematic Review and Meta-Analysis of Extraperitoneal Versus Transperitoneal Colostomy for Preventing Parastomal Hernia.

BACKGROUND: Parastomal hernia remains a frequent problem after constructing a colostomy. Current research mainly focuses on prophylactic mesh placement as an addition to transperitoneal colostomies. However, for constructing a colostomy, either an extraperitoneal or transperitoneal route can be chosen. OBJECTIVE: The aim of this meta-analysis was to investigate which technique results in lower parastomal hernia rates in patients undergoing end colostomy. DATA SOURCES: A meta-analysis was conducted according to Preferred Items for Reporting of Systematic Reviews and Meta-Analyses and Meta-Analysis of Observational Studies in Epidemiology guidelines. Embase, MEDLINE, Web of Science, Scopus, Cumulative Index to Nursing and Allied Health Literature, Cochrane, PubMed, and Google Scholar databases were searched. The study protocol was registered in the International Prospective Register of Systematic Reviews database. STUDY SELECTION: Studies comparing extraperitoneal and transperitoneal colostomies were included. Only studies written in English were included. The quality of studies and risk of bias were assessed using the Cochrane risk-of-bias tool. The quality of nonrandomized studies was assessed using the Newcastle-Ottawa Scale. INTERVENTION: The intervention was colostomy formation. MAIN OUTCOME MEASURES: The main outcome measure was parastomal hernia incidence. Secondary outcome measures were stoma prolapse, stoma necrosis, and operating time. RESULTS: Of 401 articles found, a meta-analysis was conducted of 10 studies (2 randomized controlled trials and 8 retrospective studies) composed of 1048 patients (347 extraperitoneal and 701 transperitoneal). Extraperitoneal colostomy led to significantly lower parastomal hernia rates (22 of 347 (6.3%) for extraperitoneal versus 125 of 701 (17.8%) for transperitoneal; risk ratio = 0.36 (95% CI, 0.21-0.62); I = 26%; p < 0.001) and significantly lower stoma prolapse rates (2 of 185 (1.1%) for extraperitoneal versus 13 of 179 (7.3%) for transperitoneal; risk ratio = 0.21 (95% CI, 0.06-0.73); I = 0%; p = 0.01). Differences in stoma necrosis were not significant. Operating time data were insufficient to analyze. LIMITATIONS: Most of the studies were nonrandomized, and some were not recent publications. CONCLUSIONS: Although the majority of studies included were retrospective, extraperitoneal colostomy was observed to lead to a lower rate of parastomal hernia and stoma prolapse.

Reducing colorectal anastomotic leakage with tissue adhesive in experimental inflammatory bowel disease.

BACKGROUND: Anastomotic leakage after gastrointestinal surgery remains a challenging clinical problem. This study aimed to investigate the effectiveness of TissuCol (fibrin glue), Histoacryl Flex (n-butyl-2-cyanoacrylate), and Duraseal (polyethylene glycol) on colorectal anastomotic healing during experimental colitis. METHODS: We first performed colectomy 7 days after 10 mg trinitrobenzene sulfonic acid (TNBS)-induced colitis to validate a rat TNBS-colitis-colectomy model. Subsequently, this TNBS-colitis-colectomy model was used in 73 Wistar rats that were stratified into a colitis group (CG, no adhesive), a TissuCol group (TG), a Histoacryl group (HG), and a Duraseal group (DG). Anastomotic sealant was applied with one adhesive after constructing an end-to-end hand-sewn anastomosis. Clinical manifestations, anastomotic bursting pressure, and immunohistochemistry of macrophage type-one (M1) and type-two (M2) was performed on postoperative day (POD)3 or POD7. RESULTS: TNBS-caused mucosal and submucosal colon damage and compromised anastomotic healing (i.e., abscess formation and low anastomotic bursting pressure). On POD3, higher severity of abscesses was seen in CG. Average anastomotic bursting pressure was 53.2 ± 35.5 mm Hg in CG, which was significantly lower than HG (134.4 ± 27.5 mm Hg) and DG (95.1 ± 54.3 mm Hg) but not TG (83.4 ± 46.7 mm Hg). Furthermore, a significantly higher M2/M1 index was found in HG. On POD7, abscesses were only seen in CG (6/9) but not in other groups; HG had the lowest severity of adhesion. CONCLUSIONS: We describe the first surgical IBD model by performing colectomy in rats with TNBS-induced colitis, which causes intra-abdominal abscess formation and compromises anastomotic healing. Anastomotic sealing with Histoacryl Flex prevents these complications in this model. Alternative activation of macrophages seems to be involved in its influence on anastomotic healing.

The prevention of colorectal anastomotic leakage with tissue adhesives in a contaminated environment is associated with the presence of anti-inflammatory macrophages.

BACKGROUND: Colorectal anastomoses created in a contaminated environment result in a high leakage rate. This study investigated whether using anastomotic sealants (TissuCol(®), Histoacryl(®) Flex, and Duraseal(®)) prevents leakage in a rat peritonitis model. STUDY DESIGN: Sixty-seven Wistar rats were divided into control and experimental groups (TissuCol, Histoacryl, and Duraseal groups). Peritonitis was induced 1 day before surgery with the cecal ligation puncture model. On day 0, colonic anastomosis was constructed with sutures and then sealed with no adhesive (control group) or one select adhesive (experimental groups). Bursting pressure, abscess formation, and adhesion severity were evaluated on day 3 or day 14. Hematoxylin and eosin staining and immunohistochemical staining for CD4, CD8, CD206, and iNOS were performed. RESULTS: On day 3, bursting pressures of the TissuCol group (120.1 ± 25.3 mmHg), Histoacryl group (117.3 ± 20.2 mmHg), and Duraseal group (123.6 ± 35.4 mmHg) were significantly higher than the that of the control group (24.4 ± 31.7 mmHg, p < 0.001). Abscesses around the anastomosis were found in the control group (6/7) and Duraseal group (2/9) but not in the TissuCol group or Histoacryl group. A higher number of CD206+ cells (M2 macrophages), a lower number of iNOS+ cells (M1 macrophages), a higher M2/M1 index, and a higher CD4+/CD8+ index were seen at the anastomotic site in all experimental groups compared with the control group on day 3. On day 14, abscesses were only found in the control group. Adhesion severity in the Duraseal group was significantly lower than that in the control group (p = 0.001). CONCLUSIONS: Anastomotic sealing using TissuCol(®), Histoacryl(®) Flex, or Duraseal(®) seems to be an effective and safe option to prevent leakage in contaminated colorectal surgery. The presence of large numbers of anti-inflammatory macrophages seems to be involved in preventing the leakage.