Adipose-derived mesenchymal stem cells from ventral hernia repair patients demonstrate decreased vasculogenesis

The effect of prophylactic mesh implantation on the development of incisional hernias in patients with elevated BMI: a systematic review and meta-analysis

Background

Incisional hernia is a common complication after midline laparotomy. In certain risk profiles incidences can reach up to 70%. Large RCTs showed a positive effect of prophylactic mesh reinforcement (PMR) in high-risk populations.

Objectives

The aim was to evaluate the effect of prophylactic mesh reinforcement on incisional hernia reduction in obese patients after midline laparotomies.

Methods

Following the PRISMA guidelines, a systematic literature search in Medline, Web of Science and CENTRAL was conducted. RCTs investigating PMR in patients with a BMI ≥ 27 reporting incisional hernia as primary outcome were included. Study quality was assessed using the Cochrane risk-of-bias tool and certainty of evidence was rated according to the GRADE Working Group grading of evidence. A random-effects model was used for the meta-analysis. Secondary outcomes included postoperative complications.

Results

Out of 2298 articles found by a systematic literature search, five RCTs with 1136 patients were included. There was no significant difference in the incidence of incisional hernia when comparing PMR with primary suture (odds ratio (OR) 0.59, 95% CI 0.34–1.01, p = 0.06, GRADE: low). Meta-analyses of seroma formation (OR 1.62, 95% CI 0.72–3.65; p = 0.24, GRADE: low) and surgical site infections (OR 1.52, 95% CI 0.72–3.22, p = 0.28, GRADE: moderate) showed no significant differences as well as subgroup analyses for BMI ≥ 40 and length of stay.

Conclusions

We did not observe a significant reduction of the incidence of incisional hernia with prophylactic mesh reinforcement used in patients with elevated BMI. These results stand in contrast to the current recommendation for hernia prevention in obese patients.

The Effect of Adipose-Derived Stromal Vascular Fraction Cells to Abdominal Wall Fascia Defects in Rats: An Experimental Study

OBJECTIVE

Various synthetic and biological meshes have been developed to reduce recurrence and complications in ventral incisional hernia repairs. Adipose tissue is a rich reserve for mesenchymal stromal cells. In the present study we aimed to examine the effects of adipose-derived mesenchymal stromal cells (AD-MSCs) on abdominal incisional hernia repairs in rats.

MATERIALS AND METHODS

The study involved 32 male Wistar-Albino rats, weighing 200-250 g, which were divided into three groups. In Group 1 (control group) only an incisional hernia model was created. In Group 2, the incisional hernia model was created and 1 ml stromal vascular fraction (SVF), obtained from inguinal lipectomy material and containing mesenchymal stromal cells, was injected into the edges of the defect in the same session. In Group 3, only the incisional hernia model was created in the first stage and after 14 days, 1 ml of SVF was injected into the edges of the defect. Skin incisions of rats in Group 1 and 2 were opened on postoperative day 28 while in group 3 were opened on day 42. Peritoneal formation in abdominal wall defect was evaluated macroscopically and histopathologically.

RESULTS

Peritoneal formation was significantly superior in Groups 2 and 3 than in Group 1 (p: 0.031). In histopathological evaluation, the structural distortion and polymorphonuclear leukocyte (PMNL) levels were significantly higher in Group 1 than in Group 3 (p: 0.048 and p: 0.046, respectively). Granulation, capillary density, fibrosis and collagen organization were higher in Group 2 and 3, however this difference was not statistically significant (p > 0.05).

CONCLUSIONS

Adipose-derived stromal vascular fraction cells obtained from inguinal lipectomy material in rats positively affect the repair of abdominal incisional hernias by increasing peritoneal formation, and reducing structural distortion and PMNL infiltration.

Molecular Mechanisms and Potential Therapeutic Targets in Incisional Hernia

The pathophysiology underlying the formation, progression, and surgical healing of incisional hernia (IH) that develops as a major complication associated with abdominal laparotomy is poorly understood. The proposed mechanisms include the switch of collagen phenotype and the proliferation of abnormal fibroblasts after surgery. The focus of this article was to critically review the cellular, biochemical, and potential molecular events associated with the development of IH. The disturbance in collagen homeostasis with alterations in the expression of collagen subtypes, including type 1, type 3, type 4, and type 5, and impairment in the transdifferentiation of fibroblasts to myofibroblasts are discussed. The phenotype switch of wound-repair fibroblasts results in mechanically compromised extracellular matrix that triggers the proliferation of abnormal fibroblasts. High-mobility group box 1 could be involved in wound progression, whereas signaling events mediated by tumor necrosis factor β1, connective tissue growth factor, lysyl oxidase, and hypoxia-inducible factor 1 play significant role in the wound healing response. Thus, the ratio of tumor necrosis factorβ1: high-mobility group box 1 could be a critical determinant of the underlying pathology. Potential target sites for therapeutic intervention in the management of IH are recognized.

Challenging abdominal incisional hernia repaired with platelet-rich plasma and bone marrow-derived mesenchymal stromal cells. A case report

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New treatment options for challenging procedures in hernia surgery are necessary.

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Possibility of improving prosthetic compatibility and reducing future recurrences.

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Tissue engineering offers new strategies to improve fascial healing.

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Case of a surgeon – challenging abdominal incisional hernia.

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Treatment provided was PRP and BM-MSCs on a biological mesh.

Introduction

The necessity to develop new treatment options for challenging procedures in hernia surgery is becoming even more evident and tissue engineering and biological technologies offer even newer strategies to improve fascial healing. The present case reports a patient-tailored surgical technique performed to repair a grade IV abdominal incisional hernia, with a combined use of platelet-rich plasma and bone marrow-derived mesenchymal stromal cells, implanted on a biological mesh.

Presentation of the case

A 71 year-old female patient complained of an abdominal incisional hernia, complicated by enterocutaneous fistula, four-months following laparostomy. Contrast enhanced computed tomography showed an incisional hernia defect of 15.5 × 20 cm, with a subcutaneous abscess and an intestinal loop adherent to the anterior abdominal wall, with a concomitant enterocutaneous fistula. Surgery involved abdominal wall standardized technique closure, with in addition platelet-rich plasma and bone marrow-derived mesenchymal stromal cells implanted on a biological mesh. Two years follow up showed no recurrences of incisional hernia.

Discussion

Coating surgical meshes with patient’s own cells may improve biocompatibility, by reducing inflammation and adhesion formation. Moreover, platelet-rich plasma is a good source of growth factors for wound healing, as well as a good medium for bone marrow multinucleate cells introduction into fascial repair.

Conclusion

This approach is likely to improve abdominal wall repair in high grade (IV) incisional hernia, with the real possibility of improving prosthetic compatibility and reducing future recurrences. The authors agree with the necessity of further studies and trials to assure the safety profile and superiority of this procedure.

Emerging Trends in Abdominal Wall Reinforcement: Bringing Bio-Functionality to Meshes

Abdominal wall hernia is a recurrent issue world-wide and requires the implantation of over 1 million meshes per year. Because permanent meshes such as polypropylene and polyester are not free of complications after implantation, many mesh modifications and new functionalities have been investigated over the last decade. Indeed, mesh optimization is the focus of intense development and the biomaterials utilized are now envisioned as being bioactive substrates that trigger various physiological processes in order to prevent complications and to promote tissue integration. In this context, it is of paramount interest to review the most relevant bio-functionalities being brought to new meshes and to open new avenues for the innovative development of the next generation of meshes with enhanced properties for functional abdominal wall hernia repair.