Effectiveness and versatility of biological prosthesis in transplanted patients

Abdominal wall hernia repair: from prosthetic meshes to smart materials

Hernia reconstruction is one of the most frequently practiced surgical procedures worldwide. Plastic surgery plays a pivotal role in reestablishing desired abdominal wall structure and function without the drawbacks traditionally associated with general surgery as excessive tension, postoperative pain, poor repair outcomes, and frequent recurrence. Surgical meshes have been the preferential choice for abdominal wall hernia repair to achieve the physical integrity and equivalent components of musculofascial layers. Despite the relevant progress in recent years, there are still unsolved challenges in surgical mesh design and complication settlement. This review provides a systemic summary of the hernia surgical mesh development deeply related to abdominal wall hernia pathology and classification. Commercial meshes, the first-generation prosthetic materials, and the most commonly used repair materials in the clinic are described in detail, addressing constrain side effects and rational strategies to establish characteristics of ideal hernia repair meshes. The engineered prosthetics are defined as a transit to the biomimetic smart hernia repair scaffolds with specific advantages and disadvantages, including hydrogel scaffolds, electrospinning membranes, and three-dimensional patches. Lastly, this review critically outlines the future research direction for successful hernia repair solutions by combing state-of-the-art techniques and materials.

Abdominal wall complications after kidney transplantation: A clinical review

Introduction

Abdominal wall complications are common after kidney transplantation, and although they have a minor impact on patient and graft survival, they increase the patient's morbidity and may have an impact on quality of life. Abdominal wall complications have an overall incidence of 7.7–21%.

Methods

This review will explore the natural history of abdominal wall complications in the kidney transplant setting, with a special focus on wound dehiscence and incisional herni, with a particular emphasis on risk factors, clinical characteristics, and treatment.

Results

Many patient‐related risk factors have been suggested, including older age, obesity, and smoking, but kidney transplant recipients have an additional risk related to the use of immunosuppression. Wound dehiscence usually does not require surgical intervention. However, for deep dehiscence involving the fascial layer with concomitant infection, surgical treatment and/or negative pressure wound therapy may be required.

Conclusions

Incisional hernia (IH) may affect 1.1–18% of kidney transplant recipients. Most patients require surgical treatment, either open or laparoscopic. Mesh repair is considered the gold standard for the treatment of IH, since it is associated with a low rate of postoperative complications and an acceptable rate of recurrence. Biologic mesh could be an attractive alternative in patients with graft exposition or infection.

A systematic review of outcome reporting in incisional hernia surgery

Background

The incidence of incisional hernia is up to 20 per cent after abdominal surgery. The management of patients with incisional hernia can be complex with an array of techniques and meshes available. Ensuring consistency in reporting outcomes across studies on incisional hernia is important and will enable appropriate interpretation, comparison and data synthesis across a range of clinical and operative treatment strategies.

Methods

Literature searches were performed in MEDLINE and EMBASE (from 1 January 2010 to 31 December 2019) and the Cochrane Central Register of Controlled Trials. All studies documenting clinical and patient-reported outcomes for incisional hernia were included.

Results

In total, 1340 studies were screened, of which 92 were included, reporting outcomes on 12 292 patients undergoing incisional hernia repair. Eight broad-based outcome domains were identified, including patient and clinical demographics, hernia-related symptoms, hernia morphology, recurrent incisional hernia, operative variables, postoperative variables, follow-up and patient-reported outcomes. Clinical outcomes such as hernia recurrence rates were reported in 80 studies (87 per cent). A total of nine different definitions for detecting hernia recurrence were identified. Patient-reported outcomes were reported in 31 studies (34 per cent), with 18 different assessment measures used.

Conclusions

This review demonstrates the significant heterogeneity in outcome reporting in incisional hernia studies, with significant variation in outcome assessment and definitions. This is coupled with significant under-reporting of patient-reported outcomes.

Incisional Hernia Repairs after Abdominal Organ Transplantation

Incisional hernias occur after abdominal organ transplantation with rates of 1.6 per cent to 18 per cent in kidney transplants (KTs) and 1.7 to 32.4 per cent in liver transplants (LTs). We hypothesized a difference in KTand LToutcomes in patients with and without repair of incisional hernias. We conducted a retrospective cohort study of abdominal transplants from 2012 through 2016. The difference across compared groups for continuous variables was assessed using the independent sample t test, and for binary variables, using the chi-squared test. A total of 1518 transplants were performed, including 1138 KTs and 380 LTs. There were 83 KT incisional hernias (67 repaired) and 59 LT incisional hernias (48 repaired). There was no difference between groups with regard to smoking, diabetes, age, BMI, days on dialysis (KTs), pretransplant Model for End-Stage Liver Disease (MELD) (LTs), cold ischemic time, graft survival, or recurrence rate by repair method. In the LT population, there was a statistically significant difference in days on the waitlist ( P = 0.02), drain placement ( P = 0.04), and cytomegalovirus (CMV) mismatch ( P = 0.02). Patient survival was also statistically significant for KTs ( P = 0.04) and LTs ( P = 0.01). KT and LT patients who have their incisional hernias repaired have better overall survival, regardless of the repair technique.

Incisional Hernia After Orthotopic Liver Transplantation: A Systematic Review and Meta-analysis

BACKGROUND

Incisional hernia (IH) is a well-known complication of orthotopic liver transplantation. Despite wide recognition of the impact of this problem, the incidence remains imprecisely known.

METHODS

The MEDLINE, EMBASE, Cochrane Central Register of Clinical Trials and Cochrane Database of Systematic Reviews databases were searched from their inception to November 2017 for abstracts documenting IH after orthotropic liver transplantation (OLT). The primary endpoint of this study was incidence of IH, secondary endpoints were time to hernia and recurrence. Three reviewers independently graded abstracts for inclusion in this review. Heterogeneity in combining data was assumed prior to pooling. Random-effects meta-analyses were performed to estimate percentages and 95% CIs.

RESULTS

After a review of 77 abstracts, 18 studies were graded as relevant. The methodological quality of studies was assessed with a minimum Oxford Centre for Evidence-Based Medicine level of 2B. These represent a cohort of 981 patients with IH after OLT reported in the literature. A meta-analysis of studies meeting inclusion criteria shows mean incidence of 15.1% (CI 12.1%-18.2%). Aggregate recurrence rate reported in the literature is 12.4% (CI 4.3%-20.5%). Overall reported time to IH after OLT was 42.9 months.

CONCLUSIONS

Although reported incidences of IH after OLT vary widely across studies, an overall incidence of 15.1% is reported. This is a relatively late complication after transplantation. Recurrence of hernia after initial repair is 12.4% within this patient population.

Utilization of Vicryl Bridging Mesh in Orthotopic Liver Transplantation to Achieve Tension-Free Abdominal Wall Closure: A Case Series

Difficulty in primary fascial closure of the abdomen in transplant patients is a common challenge. Abdominal wall tension may have detrimental effects on the newly transplanted graft due to compression, and blood flow hindrance, potentially leading to ischemia or thrombosis and possibly graft failure. Furthermore, patients will be at risk of developing fascial ischemia and dehiscence. Myocutaneous flaps, temporary closure with silastic mesh, abdominal wall transplants, and even graft reduction, bowel resection, and splenectomies have been practiced with varying degrees of success. In this study, we present four cases of patients who underwent orthotopic liver transplantation (OLT) with bridging Vicryl knitted mesh (ETHICON VKML VICRYL-Polyglactin 910-30 × 30 cm) to relieve the tension during the closure. Our results show that these patients, despite having a high average Model End-Stage Liver Disease (MELD) score of 25, had a good liver function at the time of discharge and continue to upon follow-up. They had a relatively short length of stay (LOS) in both the intensive care unit (ICU) and in the hospital, an average of 3.5 days and 9 days, respectively. Our case series successfully show that utilizing a bridging Vicryl knitted mesh is a reasonable approach to attain tension-free abdominal closure in OLT with satisfying results.

Biological Mesh Repair of a Large Incisional Hernia Containing a Kidney Transplant in the Presence of Inflammation

The incidence of incisional hernia after kidney transplantation varies between 1.1% and 3.8%. These are usually repaired electively using polypropylene mesh. We present here a case where a patient presented as an emergency, with a large painful incisional hernia over his kidney transplant, and evidence of local erythema and systemic inflammation. As this could have represented either infection or rejection, the patient was started on antibiotics and subsequently underwent graft nephrectomy and hernia repair using a biological (porcine-derived) acellular dermal matrix, Strattice™, with a satisfactory outcome. In addition, histology showed evidence of allograft rejection. This is the first reported case of an incisional hernia containing a rejecting kidney allograft, managed with nephrectomy and biological mesh repair.

Postoperative renal impairment is associated with increased length of stay for incisional hernia repair after liver transplantation

Background

Incisional hernia repair is the most common procedure after orthotopic liver transplantation. Although enhanced recovery protocols are increasingly employed, the post–orthotopic liver transplantation patient may not benefit from all aspects of these models. The aim of the present study is to assess which perioperative interventions and patient factors affect hospital length of stay in a cohort of post–orthotopic liver transplantation patients undergoing incisional hernia repair.

Methods

We conducted a retrospective review of a series of adult patients undergoing incisional hernia repair after orthotopic liver transplantation. The primary endpoint was length of stay. Results were stratified by demographic, intraoperative, and postoperative variables.

Results

Eleven percent (172/1523) of patients who received orthotopic liver transplantation during the study period underwent subsequent incisional hernia repair. Median length of stay was 5 days (range 2–50). The strongest predictor of length of stay was postoperative renal function. Despite liberal intraoperative administration of volume (median 642 mL/h) and brisk intraoperative urine output (median 72 mL/h), postoperative acute kidney injury occurred in 48% of patients. Those that developed acute kidney injury received less intraoperative volume (6 vs 8.5 mL/kg/h; P = .031) and the severity of postoperative renal injury was inversely related to the amount intraoperative volume given.

Conclusions

In patients undergoing incisional hernia repair after orthotopic liver transplantation, postoperative renal function is frequently impaired. Although many aspects of current ERAS protocols may be applied to post-transplant patients, restrictive intraoperative fluid administration strategies should be employed with caution given a high propensity for the development of post-operative acute kidney injury in this complex population.

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Eleven percent (172/1523) of patients who received OLT during the years 2005 to 2016 underwent subsequent IHR.

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The strongest predictor of length of stay in this population was postoperative renal function.

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Despite liberal intraoperative administration of volume (median 642 mL/h; 7 mL/kg/h) and brisk intraoperative urine output (median 72 mL/h), postoperative acute kidney injury (AKI) occurred in 48% of patients.

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Those that developed AKI received less intraoperative volume (6 vs 8.5 mL/kg/h; P = .031) and the severity of postoperative renal injury was inversely related to intraoperative volume

Component separation of abdominal wall with intraoperative botulinum A presents satisfactory outcomes in large incisional hernias: a case report

PURPOSE

Transplantation patients have a series of associated risk factors that make appearance of incisional hernia (IH) more likely. A number of aspects of the closure of large defects remain controversial. In this manuscript, we present the repair of a large IH following liver transplantation through the technique of posterior components separation combined with the anterior, together with the intraoperative use of botulinum toxin A and the placement of mesh. As a secondary objective, we analyze the incidence of IH following liver transplantation in our service.

METHODS

Between the years 2013 and 2016, 247 patients underwent liver transplantation in the Liver Transplantation Service at the Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Brazil. We analyzed the incidence of IH in these patients. One of these cases operated in March 2017 presented a defect in the abdominal wall of 22×16.6×6.4cm in the median and paramedian regions. We present the details of this innovative surgical technique.

RESULTS

The total operating time was 470min. During the postoperative phase the patient presented ileus paralysis, without systemic repercussions. Resumption of an oral diet on the fifth postoperative day, without incident. Hospital discharge occurred on the 12th postoperative day, with outpatient follow up.

CONCLUSION

In our service, the incidence of incisional hernias following liver transplantation is 14.5%. We described a successful approach for selected patient group for whom there is no established standard treatment. Given the complexity of such cases, however, more studies are necessary.