DERMAL REPLACEMENT WITH MATRIDERM – FIRST EXPERIENCE AT THE PRAGUE BURN CENTRE

INTRODUCTION

In recent decades, we have witnessed declining mortality and morbidity in burn patients¹. Already in 2012, for example, Kraft et al. published a paper on changing mortality in children treated in burn centers relative to the extent of total body surface area (TBSA) burned. Whereas 40% TBSA burned was formerly associated with a high risk of mortality, today that figure is more like 60%². Improved survival of burn patients is attributed not only to the centralization of patients and to the advances in intensive and pre-hospital care, but also to considerable developments in surgical therapy. One of the pillars of modern surgical intervention is the use of artificial skin grafts that can provide quick compensation for skin defects and lead to excellent functional and aesthetic characteristics of the resulting scars. At present, there exists an extensive selection of products on the market. The most widely used product in the world is the dermal substitute Integra^® (Integra LifeSciences, Plainsboro, NJ, USA), with which our unit has the most practical experience³. Since the year 2003, we have performed a total of 59 applications utilizing Integra^®. The greatest disadvantages of its use include the maturation time, which is approximately 3–4 weeks, and the necessity for subsequent application of an ultrathin dermoepidermal skin graft in a second operation⁴. The development of new and especially thinner materials gradually enabled using a prosthesis in a single operation along with a dermoepidermal graft. The primary representative of this trend in the development of skin substitutes is the Matriderm^® dermal template (MedSkin Solutions Dr. Suwelack, Billerbeck, Germany).

The aim of the presented paper is to present the first experience with the application of Matriderm^® at our centre during the period 2017–2020.

MATERIAL AND METHODS

Patients

At our centre, we used Matriderm^® from January 2018 to June 2020 in a total of 10 patients; 90% of whom were children. The average age in the group of children was 4 years, and 60% of the patients were males, while 40% were females. One patient was electively operated due to scar contracture. Seven patients suffered from a thermal injury, one child suffered from a rare congenital Volkmann´s ischemic contracture, and one child sustained a loss of a finger due to an injury of non-burn etiology. Matriderm^® was used in one patient during the treatment of a skin defect after a meningococcal sepsis. In nine cases was the material used on the limbs, and in one patient we used Matriderm^® on the face (see Figure 3). Seven patients were treated at our unit, the child with a loss of a finger in cooperation with the Departmend of Plastic Surgery3 FM CU and UHKV, and two children (a patient after meningococcal sepsis and a newborn with congenital skin ischemia) at the Department of Pediatric Surgery and Traumatology, 3^rd Medical Faculty, Charles University and Thomayer Hospital in Prague.

Technique of application

Matriderm^® is a dermal prosthesis consisting in a three-dimensional highly porous matrix composed of collagen I, III and V (originating from bovine dermis) and elastin (obtained by hydrolysis from bovine nuchal cartilage). A dermal matrix with a thickness of 1 mm serves as a scaffold for fibroblast proliferation and rapid angiogenesis. Elastin promotes rapid capillary growth and formation of elastic fibers. The highly porous matrix enables diffusion of nutritional factors and subsequent rapid vascularization as a condition for the survival of a thin skin graft applied to the wound bed at the same time as a dermal substitute⁵. By its design, Matriderm^® has also a hemostatic potential. It is always supplied in a sterile form (sterilization by gamma irradiation). It is easy to handle and does not require special storage or preparation⁶. Once removed from the package, Matriderm^® is applied to the wound and moistened with sterile physiological saline. This changes the material’s consistency and provides better adherence to the base of the wound. A thin dermoepidermal graft of 0.15–0.3 mm and harvested with a Zimmer^® dermatome (Zimmer Germany, Freiburg, Germany) is immediately applied to its surface. In order to achieve the best possible cosmetic result, it is important not to expand the grafts by meshing. The transplant often needs to be fixed with sutures at the edge and at the bottom of the wound. Tulle gras, antiseptic dressing, and other sterile non-adhesive dressing are applied on the graft to facilitate its efficacy. The same conditions apply to the successful application of Matriderm^® as in the cases of other skin substitutes or skin transplants. The wound must be treated after complete excision and be without infection and hematomas. The greatest danger is the presence of bacteria that cause hydrolysis of collagen matrix of the prosthesis, blocking angiogenesis and preventing its engraftment⁷. The main indications are acute skin losses at predilection sites with high risk of contractures, such as hand dorsum and defects extending to deep structures⁸. Matriderm^® is advantageously used in reconstructive surgery to treat scarring contractures⁹. It can also be used, however, for skin losses due to other etiologies, such as chronic wounds or defects after tumor excision¹⁰. The main disadvantages include its high cost and risk of infectious complications, especially when used in the acute phase of trauma¹¹. (Figure 1.)

RESULTS

The average time for complete attachment of the dermoepidermal graft to the skin matrix was 19.6 days in our group. We defined the time of complete healing as ≥95% healing of a skin graft as assessed by a specialist. Perioperative antibiotics were administered in 80% of our patients. Complications occurred in 3 patients. In 2 cases there was mechanical damage to the artificial prosthesis or transplant, while in 1 case the area was locally infected (Staphylococcus aureus) without the need for additional transplantation. (Table 1, Figure 2, Figure 3.)

DISCUSSION

The treatment of burns is based on a comprehensive approach, and the goals include not only to avoid mortality but also to the improvement of long-term quality of life of burn patients. The quality of scar tissue, in particular, plays a key role in the return of patients to normal life and full functioning in society¹². The introduction of artificial skin prostheses into clinical practice is improving the functional and cosmetic outcomes in burn patients¹³. The most widely used prosthesis worldwide is the bilaminar dermal substitute Integra^®, which is supplied with a silicone layer (functioning as a temporary epidermal cover) and its use has saved the lives of many, especially extensively burned, patients¹⁴. After successful vascularization is Integra^® providing temporary fully-sealed occlusion until the size of the harvest area allows repeated harvest of dermoepidermal grafts so that complete coverage of all areas was achieved.

Moreover, new materials, such as the single-layer dermal substitute Matriderm^®, which enables immediate coverage with a dermoepidermal graft in a single operation, are gradually being introduced to our clinical practice. In our opinion, the so-called “one-stage procedure” has indisputable advantages: it reduces the number of operations while diminishing the risk of infection, costs of treatment, and length of hospital stay. A disadvantage of this strategy is the need for an immediate application of the graft when we treat a large burn area with a limited donor site for skin harvest. For burn patients, we prefer Matriderm^® in risk areas of limited extent, the treatment of which would otherwise be associated with greatest functional and cosmetic consequences. This corresponds to the operated sites in our patients’ group. We have successfully applied Matriderm^® to areas with exposed deep structures such as the tendons. The main indication for the use of Matriderm^®, however, is in reconstructive procedures, and not only in cases of burn trauma^15,16. Published studies have shown mainly high elasticity of the resulting scars after the use of the dermal substitute Matriderm^®17. At present, there are alternative products available on the market, such as the Integra Dermal Regeneration Template Single Layer^® (Integra LifeSciences), which consists of 1.3 mm thick porous collagen and chondroitin-6-sulphate. Experimental work on an animal model, however, shows comparable biological properties during graft adhesion between Matriderm^® and the Integra^® single layer. Matriderm^®, however, has a higher degree of biodegradability, probably due to its lower density at a thickness of 1 mm¹⁸. Clinical data comparing long-term results with different substitutes are not yet available.

The greatest risk of dermal substitutes consists of infectious complications. In clinical practice and when using Integra^®, we often encounter complications in the late stages of maturation at the edges of the silicone foil. With Matriderm^®, this problem is eliminated by a single application. We did not notice any more serious infectious complications in our small patients’ group. Only one patient developed a local wound infection (S. aureus), which we managed by topical means and without the need for additional transplantation. Eighty percent of the patients in the cohort were perioperatively treated with antibiotics according to the culture from the area. Prophylactic antibiotics administration is generally not recommended in burn patients¹⁹. Indications for systemic antibiotic treatment in our group of patients were other infectious complications in the context of their underlying diseases. A widely debated issue relates to the adhesion of a thin dermoepidermal graft to the neodermis (after application of the dermal matrix). Graft take depends on the ingrowth of blood vessels from the base and interposition material (such as dermal matrix) could interfere with vascularization of the graft. The porous structure and presence of elastin enable rapid vascularization without affecting the success of the dermoepidermal graft healing. Published data agree with our interim results²⁰, whereby we observed no serious problems with graft vascularization to the neodermis. Our earliest experience has shown that it is necessary to allow longer period for graft healing. The average time of complete graft healing in our group was 
19.6 days, which is longer than reported in the literature⁸. We explain the difference by the fact that we used the substitute for complicated injuries or diseases (e.g., meningococcal sepsis) in places with limited perfusion, such as a skin defect based on ischemia in utero. Another problem related to fragility of the healed area several weeks after complete healing. This corresponds to prolonged vascularization of the graft until there is a firm connection between the graft and the neodermis. In one patient out of 10, we had to supplement a minor part of the graft with a second transplant due to anatomical complexity and the extent of damage. A child with a history of hyperkinetic disorder (ADHD) mechanically damaged the transplanted area (Figure 4). Therefore, in patients with low compliance, the indication for the use of dermal substitute must be considered on a strictly individual basis.

CONCLUSION

Based on our preliminary clinical experience, we are convinced that the Matriderm^® skin substitute represents an alternative variant to the most frequently used dermal substitute, Integra^®. The possibility for immediately covering the material with a skin graft is advantageous, as it shortens the treatment time and eliminates the two-stage operation. We see the main indication in reconstructive surgery or its use in acute treatment of thermal trauma in areas at risk of developing contractures. To assess long-term results, it will be necessary to increase the number of operated patients and objectively evaluate the nature of the resulting scar over an extended period of time.

Statement by the authors about the publication: The paper has not yet been published or simultaneously offered for publication in any other periodical, with the exception of congress abstracts and guidelines.

Declaration of acquaintance with the manuscript and consent to publication: All the stated coauthors are acquainted with the manuscript and agree with its publication.

Statement on ethical procedures used in the publication:  The procedures used in preparing the publication were in accordance with the Declaration of Helsinki 1975, as revised in 2000. The procedures used were approved by decision of the Ethics Committee of the Royal Vinohrady University Hospital EK-R-06-20 from 22 June 2020.

Statement on conflicts of interest: All authors of the paper declare that in connection with the topic, origin and publication of this article there exists no conflict of interest and the creation and publication of the article was not supported by any pharmaceutical company.

Role of authors: R. Zajíček – responsible for writing the publication, its basic concept and final form, communication with the editorial office, and responses to comments from reviewers. H. Šuca – observation of the healing process, collection of patient data, elaboration of tables and photographic documentation and their descriptions. I. Grossová – monitoring of the healing process, photographing of patients and photo processing, and preparation of literature sources and their research. V. Fetissov – translation of the article into English, proofreading. I. Pafčuga – overseeing the observation of patients, monitoring and data control, selection of photographic documentation, monitoring of compliance with ethical principles.

Corresponding author:

Robert Zajíček, MD

Department of Burn Medicine, 3^rd Faculty of Medicine, Charles University and University Hospital Královské Vinohrady Šrobárova 50

100 34 Prague 10 Czech Republic

E-mail: ZajicekRobert@seznam.cz