Telemedicine-based new patient consultations for hernia repair and advanced abdominal wall reconstruction.

PURPOSE: Telemedicine has emerged as a viable option to in-person visits for the evaluation and management of surgical patients. Increased integration of telemedicine has allowed for greater access to care for specific patient populations but relative outcomes are unstudied. Given these limitations, we sought to evaluate the efficacy of telemedicine-based new patient preoperative encounters in comparison to in-person encounters. METHODS: We performed a retrospective analysis of adult patients undergoing new patient evaluations from April 2020 to October 2021. Telemedicine visits consist of both video and telephone-based encounters. Visit types, patient demographics, preoperative diagnosis, travel time to the hospital, and prior imaging availability were reviewed. RESULTS: A total of 276 new patient encounters were conducted (n = 108, 39% telemedicine). Indications for evaluation included inguinal hernia (n = 81, 30%), ventral hernia (n = 149, 54%) and groin or abdominal pain (n = 30, 11%). Patients undergoing telehealth evaluations were more likely to have greater travel distance to the hospital (91 km vs 29 km, p = 0.002) and have CT image-confirmed diagnoses at the initial visit (73 vs 47%, p < 0.001). Patients who were evaluated for a recurrent or incisional hernia were more likely to be seen through a telemedicine encounter (69 vs 45%, p < 0.001). CONCLUSIONS: We report the efficacy of telemedicine-based consultations for new patient preoperative evaluations related to hernia repair and abdominal wall reconstruction. Telemedicine is a useful modality for preoperative evaluation of new patients with hernia and advanced abdominal wall reconstruction needs. Understanding this patient population will allow us to optimize telemedicine encounters for new patients and improve access to care for patients in remote locations.

Sarcopenia and outcomes in ventral hernia repair: a preliminary review.

PURPOSE: Sarcopenia, or loss of muscle mass, is associated with increased morbidity and mortality in oncologic resections and several other major surgeries. Complex ventral hernia repairs (VHRs) and abdominal wall reconstruction are often performed in patients at high risk for morbidity and recurrence, though limited data exist on outcomes related to sarcopenia. We aimed to determine if sarcopenia is associated with worse outcomes in patients undergoing VHR. METHODS: We reviewed patients undergoing VHRs from 2014 to 2015. Preoperative CT images were analyzed for cross-sectional muscle mass. Patients with and without sarcopenia underwent statistical analysis to evaluate differences in perioperative morbidity and hernia recurrence. Muscle indices were analyzed independently for outcomes. RESULTS: 135 patients underwent VHR with/without fistula takedown, staged repairs or other concomitant procedures. 27% had sarcopenia (age 34-84, BMI 27-33, 62% male). Postoperative complications occurred in 43% of sarcopenic patients and 47% of non-sarcopenic patients (p = 0.70). Surgical site infections (SSI) were seen in 16% of sarcopenic patients compared to 29% without sarcopenia (p = 0.14). There was no difference in hernia recurrence between groups (p = 0.90). However, after adjusting for diabetes and BMI, a 10 cm2/m2 decrease in muscle index had 1.44 OR of postoperative complications (p < 0.05). CONCLUSIONS: Though prevalent in our population, sarcopenia was not associated with an increase in postoperative complications, surgical site occurences/infections,  or hernia recurrence when previously published oncologic sarcopenia cutoffs were utilized. Previously established sarcopenia outcomes in malignancy may be attributable to an altered metabolic state that is not present in hernia repair patients. Larger-scale studies are recommended to establish new sarcopenia cutoffs for VHRs.

Repair of massive ventral hernias with "quilted" mesh.

INTRODUCTION: Prosthetic reinforcement is a critical component of hernia repair. For massive defects, mesh overlap is often limited by the dimensions of commercially available implants. In scenarios where larger mesh prosthetics are required for adequate reinforcement, it may be necessary to join several pieces of mesh together using non-absorbable suture. Here, we report our outcomes for abdominal wall reconstructions in which "quilted" mesh was utilized for fascial reinforcement. METHODS: Patients undergoing open incisional hernia repair utilizing posterior component separation and transversus abdominis muscle release, with use of quilted synthetic mesh placed in the retromuscular position, were reviewed. Main outcome measures included patient, hernia, and operative characteristics and post-operative outcomes, including surgical site occurrence (SSO), surgical site infection (SSI), and recurrence. RESULTS: Thirty-two patients (mean age 55.7 ± 9.3, BMI 38.3 ± 5.8 kg/m(2)) underwent open ventral hernia repair with "quilted" mesh placed in the retromuscular position. The mean defect area was 760.1 ± 311.0 cm(2) with a mean width of 24.7 ± 6.4 cm. Quilted meshes consisted of two-piece (69 %), three-piece (19 %) and four-piece (12 %) configurations. Wound morbidity consisted of eight (25 %) SSOs, including four (13 %) SSIs, all of which resolved without mesh excision. With mean follow-up of 9.0 ± 13.6 months, there were two (6.3 %) lateral recurrences, both unassociated with mesh-to-mesh suture line failure. CONCLUSIONS: Massive ventral hernias that require giant mesh prosthetics, currently not commercially available, may be successfully repaired using multiple mesh pieces sewn together in a quilt-like fashion. Such retromuscular repairs are durable, without added morbidity due to the mesh-to-mesh suture line. However, additional operative time is required for quilting the mesh together, prompting strong calls for manufacturing of larger mesh prosthetics.

Central failures of lightweight monofilament polyester mesh causing hernia recurrence: a cautionary note.

INTRODUCTION: Uncoated, lightweight, macroporous,monofilament mesh has been shown to demonstrate improved bacterial clearance, better tissue integration,reduced foreign body response, and less chronic pain with equivalent durability for hernia repair. These findings led us to use a new lightweight monofilament polyester mesh (Parietex TCM, Covidien). Here, we report our experience with this mesh in open incisional hernia repair. METHODS: Patients undergoing incisional hernia repair with Parietex TCM were retrospectively identified within our prospectively maintained database. Patient demographics,operative characteristics, and follow-up were reviewed. Outcome parameters included 90-day wound morbidity and hernia recurrence. RESULTS: In 2011, 36 patients (mean age 56.8; mean BMI32.4 kg/m2) underwent open incisional hernia repair with retrorectus mesh placement by two surgeons (MJR, YWN) at Case Medical Center. Anterior and posterior fascial closure was achieved in all cases. Wound morbidity included seven surgical site occurrences: four superficial infections that resolved with antibiotics, one wound dehiscence requiring wet-to-dry packing, and two seromas that resolved without intervention. With a mean follow-up of 13 months, 8 (22%) recurrences have occurred. On reoperation, 7 (19%) of these patients had mechanical failure or fracturing of the mesh. No confounding variables were identified by univariate analysis of patient demographics,operative characteristics, or wound morbidity. CONCLUSION: Lightweight monofilament polyester mesh (Parietex TCM) appears to have a high incidence of mechanical failure in the context of open incisional hernia repair. While this limitation may ultimately be revealed asa weakness of all lightweight mesh, surgeons should be aware that these failures have already been documented.

Comparative analysis of histopathologic responses to implanted porcine biologic meshes.

OBJECTIVES: Biologic mesh (BM) prostheses are increasingly utilized for hernia repairs. Modern BMs are not only derived from different tissue sources, but also undergo various proprietary processing steps-factors that likely impact host tissue responses and mesh performance. We aimed to compare histopathologic responses to various BMs after implantation in a mouse model. MATERIALS AND METHODS: Five-mm samples of non-crosslinked [Strattice (ST)], and intentionally crosslinked [CollaMend (CM), Permacol (PC)] porcine-derived biologic meshes were implanted subcutaneously in C57BL/6 mice. 1, 4, 8, and 12 weeks post-implantation, meshes were assessed for inflammation, foreign body reaction (FBR), neocellularization, and collagen deposition using H&E and trichrome stains. RESULTS: All meshes induced early polymorphonuclear cell infiltration (highest in CM; lowest in ST) that resolved by 4 weeks. ST was associated with extensive macrophage presence at 12 weeks. Foreign body response was not seen in the ST group, but was present abundantly in the CM and PC groups, highest at 8 weeks. New peripheral collagen deposition was seen only in the ST group at 12 weeks. Collagen organization was highest in the ST group as well. Both CM and PC groups were associated with fibrous encapsulation and no evidence of integration or remodeling. CONCLUSIONS: Inflammation appears to be a common component of integration of all biologic meshes studied. Pronounced inflammatory responses as well as profound FBR likely lead to observed encapsulation and poor host integration of the crosslinked BMs. Overall, ST was associated with the lowest foreign body response and the highest degree of new collagen deposition and organization. These features may be key predictors for improved mesh performance during hernia repair.

Effect of patient and hospital characteristics on outcomes of elective ventral hernia repair in the United States.

PURPOSES: Our ability to predict complications of ventral hernia repairs (VHR) are inadequate. Although impact of patient comorbidities and hospital characteristics on outcomes of several surgical procedures has been reported, such analysis on elective herniorrhaphy has not been performed to date. We hypothesized that obesity and diabetes as well as socioeconomic factors would have deleterious outcomes on elective VHR. METHODS: Analysis of 2004-2008 Nationwide Inpatient Sample database. Main outcome measures included wound/systemic morbidity, length of stay, discharge status, and in-hospital mortality. Bivariate and multivariate analyses were performed to assess influence of diabetes, obesity, patient socioeconomic factors, and hospital characteristics on the outcomes of VHR. RESULTS: A total of 78,348 adults undergoing elective VHR were analyzed. Obesity had significant risks for cardiopulmonary complications and prolonged hospitalization. Diabetics were more likely to have delayed wound healing. Hispanic patients had significantly higher rates of pulmonary complications and mortality. As compared to private insurance patients, Medicaid and Medicare patients had significantly higher odds of complications, prolonged hospitalization, non-routine discharge, and mortality. CONCLUSION: Obesity and diabetes appear to be significant predictors of morbidity in patients undergoing elective VHR. Alarmingly, Medicare/Medicaid patients not only had the highest rates of wound/systemic complications but also the highest post-operative mortality. For the first time, we demonstrated that in addition to comorbidities, both patient socioeconomic factors and hospital characteristics appear to be major determinants of post-herniorrhaphy complications and mortalities. Improved health maintenance and reduction in income-related disparities in health care delivery may be paramount in improving outcomes of VHR in the United States.

Anisotropic evaluation of synthetic surgical meshes.

INTRODUCTION: The material properties of meshes used in hernia repair contribute to the overall mechanical behavior of the repair. The anisotropic potential of synthetic meshes, representing a difference in material properties (e.g., elasticity) in different material axes, is not well defined to date. Haphazard orientation of anisotropic mesh material can contribute to inconsistent surgical outcomes. We aimed to characterize and compare anisotropic properties of commonly used synthetic meshes. METHODS: Six different polypropylene (Trelex(®), ProLite™, Ultrapro™), polyester (Parietex™), and PTFE-based (Dualmesh(®), Infinit) synthetic meshes were selected. Longitudinal and transverse axes were defined for each mesh, and samples were cut in each axis orientation. Samples underwent uniaxial tensile testing, from which the elastic modulus (E) in each axis was determined. The degree of anisotropy (λ) was calculated as a logarithmic expression of the ratio between the elastic modulus in each axis. RESULTS: Five of six meshes displayed significant anisotropic behavior. Ultrapro™ and Infinit exhibited approximately 12- and 20-fold differences between perpendicular axes, respectively. Trelex(®), ProLite™, and Parietex™ were 2.3-2.4 times. Dualmesh(®) was the least anisotropic mesh, without marked difference between the axes. CONCLUSION: Anisotropy of synthetic meshes has been underappreciated. In this study, we found striking differences between elastic properties of perpendicular axes for most commonly used synthetic meshes. Indiscriminate orientation of anisotropic mesh may adversely affect hernia repairs. Proper labeling of all implants by manufacturers should be mandatory. Understanding the specific anisotropic behavior of synthetic meshes should allow surgeons to employ rational implant orientation to maximize outcomes of hernia repair.

Effects of mast cell modulation on early host response to implanted synthetic meshes.

INTRODUCTION: Mast cells (MCs) and their products (e.g., histamine, serotonin, heparin, prostaglandins, cytokines, etc.) play key roles in controlling local inflammation, wound healing, and foreign body reactions in vivo. Investigation of the role of MCs in mediating local tissue responses to synthetic hernia meshes has been very limited to date. We aimed to determine the effects of MCs/MC products in mice undergoing synthetic mesh implantation. MATERIALS AND METHODS: Circular samples (5 mm) of heavyweight microporous polypropylene (Trelex), midweight microporous polypropylene (ProLite), lightweight macroporous polypropylene with poliglecaprone (Ultrapro), and 3-dimensional macroporous polyester (Parietex) meshes were implanted subcutaneously in C57BL/6 J mice with and without cromolyn (MC stabilizer/suppressant) treatment (50 mg/kg, daily IP). Two weeks post-implantation, all meshes were explanted and evaluated histologically using H&E and trichrome stains. RESULTS: Chronic inflammation was focused around individual mesh fibers; inter-fiber inflammation and fibrosis diminished as mesh porosity increased. MC accumulation was seen at the periphery of inflammatory reactions, and in association with mesh-induced fibrosis and neovascularization. Cromolyn treatment resulted in significantly decreased fibrotic responses to all four meshes and reduced inflammation induced by Trelex, ProLite, and Parietex meshes but not Ultrapro. CONCLUSION: We demonstrated that MCs play important roles in mesh-induced host tissue reactions. Blocking MC degranulation decreased early inflammation and fibrosis induced by most synthetic meshes in this study. Further evaluation and understanding of the role of MCs in mesh-induced tissue reactions will provide new therapeutic approaches to enhance the biocompatibility of surgical meshes and ultimately improve clinical outcomes in patients undergoing hernia repair with synthetic biomaterials.

Activation of human mononuclear cells by porcine biologic meshes in vitro.

INTRODUCTION: While porcine-based biologic meshes are increasingly used for hernia repair, little data exist on tissue responses to such products. Host foreign body reaction, local inflammation, and wound healing are principally controlled by monocytes/macrophages (M/MØs). Exaggerated activation of M/MØs may deleteriously influence mesh integration and remodeling. We hypothesized that common porcine meshes induce the differential activation of M/MØs in vitro. MATERIALS AND METHODS: Samples of four acellular porcine-derived meshes, CollaMend (CM; C.R. Bard/Davol), Permacol (PC; TSL/Covidien), Strattice (ST; LifeCell), and Surgisis (SS; Cook Biotech), were exposed to mononuclear cells derived from the peripheral blood of six healthy subjects. Following a 7-day incubation period, supernatants were assayed for interleukin-1beta (IL-1beta), interleukin-6 (IL-6), interleukin-8 (IL-8), and vascular endothelial growth factor (VEGF) using a multiplex bead-based immunoassay system. The four groups were compared using analysis of variance (ANOVA) and Student's t-test. RESULTS: Each mesh type induced differential mononuclear cell activation in vitro. The mean IL-1beta expressions for CM (7,195 pg/ml) and PC (4,215 pg/ml) were significantly higher compared to ST and SS (123 and 998 pg/ml, respectively; P < 0.05). Similar trends were also seen for IL-6 (range 445-70,729 pg/ml), IL-8 (range 11,640-1,045,938 pg/ml), and VEGF (range 686-7,133 pg/ml). CONCLUSION: For the first time, we demonstrated that porcine meshes induce M/MØ activation in vitro. CM and PC (chemically crosslinked dermis) induced significantly higher cytokine expression compared to ST (non-crosslinked dermis) and SS (small intestine submucosa). These differences are likely related to proprietary processing methods and/or the extent of collagen crosslinking. Further understanding of immunologic effects of porcine-derived biologic meshes will not only allow for a comparison between existing products, but it may also lead to mesh modifications and improvement of their clinical performance.