Porcine dermal collagen graft in pediatric renal transplantation

Children Are Not Small Adults: Similarities and Differences in Renal Transplantation Between Adults and Pediatrics

Kidney transplantation is the treatment of choice for all patients with end-stage kidney disease, including pediatric patients. Graft survival in pediatrics was lagging behind adults, but now is comparable with the adult cohort. Although many of the protocols have been adopted from adults, there are issues unique to pediatrics that one should be aware of to take care of this population. These issues include recipient size consideration, increased incidence of viral infections, problems related to growth, common occurrence of underlying urological issues, and psychosocial issues. This article addresses the similarities and differences in renal transplantation, from preparing a patient for transplant, the transplant process, to post-transplant complications.

Introducing a New Technique for Fascial Closure to Avoid Renal Allograft Compartment Syndrome in Pediatric Recipients: The Use of Tutoplast® Fascia Lata

Introduction

Renal allograft compartment syndrome (RACS) is a complication that infrequently occurs after renal transplantation. Tight muscle closure may lead to RACS due to compression of renal parenchyma or kinking of the renal vessels. Many techniques have been proposed in an attempt to achieve tension-free closure, which can be specially challenging in child recipients. We present our experience with Tutoplast^® Fascia Lata (RTI Surgical Tutogen Medical GmbH Industriestrasse 6, 91077 Neunkirchen am Brand, Germany) closure.

Methods

All pediatric patients who underwent renal transplantation in our center between 2012 and 2021 were reviewed. Eight patients with Tutoplast^® Fascia Lata placed at the time of initial transplantation were identified. Donor and recipient characteristics, Doppler ultrasound findings, and overall patient and graft survival rates were analyzed.

Results

Doppler ultrasound was performed intra-operatively after abdominal wall closure. If any sign of vascular compromise was seen, the abdominal wall was opened and the graft was revised. The Tutoplast^® Fascia Lata implant was used to perform tension-free fascia closure and, afterwards, a Doppler ultrasound was performed to confirm the optimal renal artery perfusion and venous patency. Three of the renal transplantations were from a cadaver donor, with two of them en bloc. Living donor transplantation was performed in four cases. Among which, there was a case of auto-transplantation due to bilateral renal artery stenosis. None of the patients presented any complications of either short or long term that was derived from the abdominal closure with Tutoplast^® Fascia Lata. There was also no record of graft failure till datum.

Conclusions

Restricted volume of the recipient pelvic cavity and the size discrepancy between the recipient pelvic cavity space and the donor adult kidney may lead to RACS. Other situations that occur more infrequently, i.e., as en bloc or auto-transplantation, are prone to suffer the same problem. Tutoplast^® Fascia Lata is a safe option for these patients.

Renal allograft compartment syndrome: a review

Renal allograft compartment syndrome (RACS) is the result of extrinsic compression resulting in graft dysfunction and loss due to ischaemia. A literature review was performed by computerized searches from the following data sources Medline, EMBASE, PubMed and Cochrane Library databases. Risk factors include size mismatch between graft and recipient. Intraoperative suspicion should be exercised if there is poor tissue turgor, cyanosis and loss of urine output upon fascial closure. Doppler ultrasound is the modality of choice amongst the literature to aid in diagnosis of RACS. From our study, the accepted form of treatment is early detection and appropriate surgical intervention. Nevertheless, it is clear from the paucity of literature that further investigation into this area of transplantation is necessary.

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.

Prophylactic onlay reinforcement with absorbable mesh (polyglactin) is associated with less early wound complications after kidney transplantation: A preliminary study

Incidence of wound complications after kidney transplantation (KTx) is still considerable. Here, we report the impact of prophylactic absorbable polyglactin (Vicryl®) mesh reinforcement on the incidence of short-term post-KTx wound complications. Sixty-nine patients were analyzed; 23 with and 46 without preventive onlay mesh reinforcement. Surgical site infections (SSI) were seen in six (26%) patients in the mesh group and in 17 (37%) patients in no-mesh group. A lower, but not statistically significant, rate of early postoperative wound complications occurred in the mesh group. Wound complications were observed in seven (30%) patients in the mesh group and in 23 (50%) patients in the no-mesh group. There was no association between mesh placement and SSI incidence (odds ratios [OR] 0.60, 95% confidence interval [CI] 0.20-1.82, p = 0.369) and wound complications (OR 0.44, 95% CI 0.15-1.26, p = 0.126). Therefore, we conclude that mesh reinforcement does not increase the risk of SSI and overall wound complications. Long-term outcomes have to be evaluated in a randomized trial setting. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:67-72, 2020.

"Complex abdominal wall" management: evidence-based guidelines of the Italian Consensus Conference

To date, there is no shared consensus on a definition of a complex abdominal wall in elective surgery and in the emergency, on indications, technical details, complications, and follow-up. The purpose of the conference was to lay the foundations for a homogeneous approach to the complex abdominal wall with the primary intent being to attain the following objectives: (1) to develop evidence-based recommendations to define “complex abdominal wall”; (2) indications in emergency and in elective cases; (3) management of “complex abdominal wall”; (4) techniques for temporary abdominal closure. The decompressive laparostomy should be considered in a case of abdominal compartment syndrome in patients with critical conditions or after the failure of a medical treatment or less invasive methods. In the second one, beyond different mechanism, patients with surgical emergency diseases might reach the same pathophysiological end point of trauma patients where a preventive “open abdomen” might be indicated (a temporary abdominal closure: in the case of a non-infected field, the Wittmann patch and the NPWT had the best outcome followed by meshes; in the case of an infected field, NPWT techniques seem to be the preferred). The second priority is to create optimal both general as local conditions for healing: the right antimicrobial management, feeding—preferably by the enteral route—and managing correctly the open abdomen wall. The use of a mesh appears to be—if and when possible—the gold standard. There is a lot of enthusiasm about biological meshes. But the actual evidence supports their use only in contaminated or potentially contaminated fields but above all, to reduce the higher rate of recurrences, the wall anatomy and function should be restored in the midline, with or without component separation technique. On the other site has not to be neglected that the use of monofilament and macroporous non-absorbable meshes, in extraperitoneal position, in the setting of the complex abdomen with contamination, seems to have a cost effective role too. The idea of this consensus conference was mainly to try to bring order in the so copious, but not always so “evident” literature utilizing and exchanging the expertise of different specialists.

Effectiveness and properties of the biological prosthesis Permacol™ in pediatric surgery: A large single center experience

INTRODUCTION

The use of prosthetic patches of non-absorbable materials represents a valid tool in the treatment of abdominal wall and diaphragmatic defects in pediatric age. In recent years research has developed biological dermal scaffolds made from a sheet of acellular matrix that can provide the desired support and reduce the occurrence of complications from non-absorbable implant. We present our experience and a systematic review to evaluate the use of biologic prosthesis for abdominal wall closure in pediatric patients.

METHODS

The study from January 2009 to January 2015 involved 20 patients treated with Permacol™ implant. We observed postoperative complications only in patients treated for abdominal wall closure, which is the major indication for the use of Permacol™. We conducted a systematic review and meta-analysis (according to PRISMA) on PubMed/Medline, Scopus and EMBASE regarding the use of biological prosthesis in pediatric population considering the incidence of complications as the primary outcome.

RESULTS

3/20 patients experienced complications: 2 patients with skin necrosis healed conservatively and 1 of them developed laparocele. Thus only 1 patient with incisional hernia had significant surgery complication. In patients who were permanently implanted with Permacol™ it has not determined adverse reactions with optimal functional outcome.

CONCLUSIONS

In accordance with the few data (case reports and case series) reported in literature about pediatric patients, our experience in different pathologies and applications has shown the effectiveness of Permacol™, in particular for the non-occurrence of infections, that often affect the use of prosthesis.

Porcine acellular dermal matrix for delayed abdominal wall closure after pediatric liver transplantation

Children are one of the groups with the highest mortality rate on the waiting list for LT. Primary closure of the abdominal wall is often impossible in the pediatric population, due to a size mismatch between a large graft and a small recipient. We present a retrospective cohort study of six pediatric patients, who underwent delayed abdominal wall closure with a biological mesh after LT, and in whom early closure was impossible. A non-cross-linked porcine-derived acellular dermal matrix (Strattice(™) Reconstructive Tissue Matrix; LifeCell Corp, Bridgewater, NJ, USA) was used in all of the cases of the series. After a mean follow-up of 26 months (21-32 months), all patients were asymptomatic, with a functional abdominal wall after physical examination. Non-cross-linked porcine-derived acellular dermal matrix (Strattice(™) ) is a good alternative for delayed abdominal wall closure after pediatric LT. Randomized controlled trials are necessary to determine the best moment and the best technique for abdominal wall closure.

Evaluation of a porcine dermal collagen (permacol) implant for abdominal wall reconstruction in a pediatric multitrauma patient

The presence of a contaminated surgical field in abdominal wall defects caused by trauma presents a challenge for surgeons. Both primary suture and synthetic meshes are strongly discouraged as surgical treatments in such cases. We describe the use of a porcine dermal collagen (Permacol) implant in an eight-year-old patient with multiple injuries. Three months after discharge, the child remains well with good cosmetic results. He is free of pain and has returned to full activity levels with complete wound closure and without any evidence of residual hernia. In conclusion, our experience indicates that the use of Permacol can be considered an efficient technique for reconstructing an infected abdominal wall defect of a pediatric multitrauma patient.

Donor-recipient size mismatch in paediatric renal transplantation

Introduction. End stage renal failure in children is a rare but devastating condition, and kidney transplantation remains the only permanent treatment option. The aim of this review was to elucidate the broad surgical issues surrounding the mismatch in size of adult kidney donors to their paediatric recipients. Methods. A comprehensive literature search was undertaken on PubMed, MEDLINE, and Google Scholar for all relevant scientific articles published to date in English language. Manual search of the bibliographies was also performed to supplement the original search. Results. Size-matching kidneys for transplantation into children is not feasible due to limited organ availability from paediatric donors, resulting in prolonged waiting list times. Transplanting a comparatively large adult kidney into a child may lead to potential challenges related to the surgical incision and approach, vessel anastomoses, wound closure, postoperative cardiovascular stability, and age-correlated maturation of the graft. Conclusion. The transplantation of an adult kidney into a size mismatched paediatric recipient significantly reduces waiting times for surgery; however, it presents further challenges in terms of both the surgical procedure and the post-operative management of the patient's physiological parameters.

Chest wall repair in Poland syndrome: complex single-stage surgery including Vertical Expandable Prosthetic Titanium Rib stabilization--a case report

Various surgical techniques have been described for repair of chest wall defects in Poland syndrome. We describe the case of a 16-year-old boy who underwent autologous rib transposition after sternal osteotomy. Chest wall stabilization was achieved using a combination of K-wires and Vertical Expandable Prosthetic Titanium Rib (Synthes GmbH, Freiburg, Germany). Reconstruction of the soft tissue defect was accomplished by combined latissimus dorsi muscle flap and Permacol patch (Covidien Deutschland GmbH, Neustadt, Germany). This approach might be considered an effective 1-stage treatment option of this condition in postpubescent boys.

Permacol: a potential biologic patch alternative in congenital diaphragmatic hernia repair

PURPOSE

Recurrence is a well-known complication after patch repair of congenital diaphragmatic hernia (CDH). We propose that a newer, "bioprosthetic" material may lower recurrence rates. The purpose of this study is to compare outcomes of CDH repair with synthetic Gore-Tex (W. L. Gore and Associates, Neward, Del) to the bioprosthetic Permacol (Tissue Science Laboratories Inc, Andover, Mass).

METHODS

We performed a retrospective review of 100 consecutive patients with CDH with survival more than 30 days at Children's Medical Center of Dallas (Dallas, Tex) from 1999 to 2007. The incidence and timing of recurrence, as well as comorbidities were assessed.

RESULTS

Primary repair was performed in 63 patients and patch repair in 37, divided between Gore-Tex (29) and Permacol (8). Overall recurrences were as follows: 1 (2%), 8 (28%), and 0 in the primary, Gore-Tex, and Permacol groups, respectively. Median follow-up was 57 months for Gore-Tex and 20 months for Permacol. Median time to recurrence in the Gore-Tex group was 12 months, with no Permacol recurrences. Both the Gore-Tex and Permacol groups had similar comorbidities, including prematurity, congenital heart disease (76% and 63%, respectively), and the need for extracorporeal membrane oxygenation support (38% and 25%).

CONCLUSION

Our results suggest that Permacol may have lower recurrence rates compared to Gore-Tex and is a promising alternative biologic graft for CDH repair.

Biomaterial scaffolds in pediatric tissue engineering

This article reviews recent developments and major issues in the use and design of biomaterials for use as scaffolds in pediatric tissue engineering. A brief history of tissue engineering and the limitations of current tissue-engineering research with respect to pediatric patients have been introduced. An overview of the characteristics of an ideal tissue-engineering scaffold for pediatric applications has been presented, including a description of the different types of scaffolds. Applications of scaffolds materials have been highlighted in the fields of drug delivery, bone, cardiovascular, and skin tissue engineering with respect to the pediatric population. This review highlights biomaterials as scaffolds as an alternative treatment method for pediatric surgeries due to the ability to create a functional cell-scaffold environment.

The use of porcine dermal collagen implants in assisting abdominal wall closure of pediatric renal transplant recipients with donor size discrepancy

Children may have kidneys transplanted from donors larger than themselves. Abdominal wall closure may be difficult, with risks of abdominal compartment syndrome and graft compromise. Meshes used to facilitate closure may cause dense intra-abdominal adhesions, making further surgery or peritoneal dialysis difficult. We present five cases in which abdominal wall closure was facilitated by porcine dermal collagen implant. Five children (2-15 yr) received transplanted kidneys from adult donors of significantly greater weight. In four recipients, the kidney was transplanted onto the aorta and vena cava intra-abdominally using a midline incision. In the fifth, the kidney was anastomosed onto the iliac vessels. The skin overlying the implant was closed normally. Maximum follow-up was three yr. In all cases, primary closure was achieved. One child received a second intra-abdominal transplant as an emergency, which later failed. The other kidneys are functioning well. One recipient developed a small incisional hernia three yr post-transplant. Another developed a skin dehiscence over the implant 23 days post-operatively. The implant was removed and skin closed. The other two recipients recovered well. Porcine dermal collagen implant is a helpful adjunct to abdominal wall closure following organ transplantation in children with donor size discrepancy.

Abdominal wall reconstruction using biological tissue grafts: present status and future opportunities

Surgeons often encounter the challenge of treating acquired abdominal wall defects following abdominal surgery. The current standard of practice is to repair most defects using permanent synthetic mesh material. Mesh augments the strength of the weakened abdominal wall fascia and enables the hernia repair to be performed in a tension-free manner. However, there is a risk of acute and/or chronic infection, fistula formation and chronic abdominal wall pain with the use of permanent mesh materials, which can lead to more complex operations. As a means to avoid such problems, surgeons are turning increasingly to the use of xenogenic and allogenic materials for the repair of abdominal wall defects. Their rapid evolution and introduction into the clinical operating room is leading to a new era in abdominal wall reconstruction. There are promising, albeit limited, clinical data with short-term follow-up for only a few of the many biological tissue grafts that are being promoted currently for the repair of abdominal hernias. Additional clinical studies are required to better understand the long-term efficacy and limitations of these materials.

PTFE Mesh in Renal Allograft Compartment Syndrome

We report a case of anuria in a 42-year-old female kidney transplant patient that occurred secondary to extrinsic compression from a large kidney being placed extraperitoneally in a small iliac fossa. Prompt reexploration in the immediate postoperative period resulted in salvage of the graft with restoration of kidney function. The abdominal wall was reconstructed using prosthetic mesh, which decreased the compartment pressure within the iliac fossa sufficiently to allow the renal vein patency and the kidney perfusion. We think that this tension-free surgical technique should be applied in those cases in which the retroperitoneal space is less than the size of the kidney to avoid renal allograft compartment syndrome or incisional hernia.