A paradigm shift in practice-the benefits of early active wound temporisation rather than early skin grafting after burn eschar excision

Outcomes of Biodegradable Temporizing Matrix for Soft Tissue Reconstruction of the Hand and Extremities

Background

NovoSorb biodegradable temporizing matrix (BTM) is a novel, bilayer, synthetic skin substitute made of biodegradable polyurethane foam covered with a sealing membrane. BTM has demonstrated excellent outcomes in burn literature; however, few studies have been published for hand and extremity soft tissue reconstruction.

Methods

All patients who underwent extremity reconstruction with BTM from 2018 to 2023 were reviewed. Demographics, presentations, and clinical outcomes were recorded.

Results

A total of 86 cases from 54 patients (53.7% pediatric; age range: 0-81 years) were included. Common indications included trauma (36%), infection (18.6%), and malignancy (11.6%). BTM was placed over exposed tendon (38.4%), bone (19%), joints (12.8%), nerves (8.1%), and/or blood vessels (7%). BTM served as temporary wound coverage in 26 cases. Complications included hematoma (8.1%), infection (4.7%), and spontaneous delamination (4.7%). Wound closure was successfully obtained without flap use in 93.3%. Poor BTM take was associated with peripheral vascular disease, hypertension, immunosuppression, and BTM hematoma and infection (<0.05).

Conclusion

This study contributes to the growing body of evidence favoring BTM use in challenging reconstructive cases. Although prospective comparative studies are forthcoming, BTM likely has broad applications in reconstructive surgery.

Clinical outcomes and resource utilisation in patients with major burns treated with NovoSorb® BTM

INTRODUCTION

Patients with major burns can undergo temporary coverage while skin graft donor sites heal, where dermal templates have an emerging role. The aim of this study was to evaluate the clinical outcomes and resource utilisation in patients with major burns treated with a bilayer biodegradable synthetic matrix (NovoSorb BTM).

METHOD

This retrospective cohort study included patients admitted to the Royal Brisbane and Women's Hospital Adult Burn Unit with burns to at least 40 % TBSA who survived their acute admission. Patients treated from July 2017 to June 2022 with BTM were compared with patients with similar injuries treated using cadaveric allograft as temporising full thickness wound coverage between January 2013 and June 2017. Outcomes measures included number of operations, total operative time, hospital and intensive care unit (ICU) length of stay (LOS), cadaveric allograft and BTM use, and blood product use. Unadjusted comparisons were made with Wilcoxon Rank-Sum tests and Fisher's exact tests. Multivariate linear regression was used to adjust for the effect of TBSA on each outcome.

RESULTS

Fifty-five patients were included (78 % male), 22 of whom were treated with BTM. We found no significant differences in age, sex, or TBSA between groups. One patient had half of the BTM removed due to infection and replaced with allograft. Patients treated with BTM had significantly less operative theatre time (median 1361.5 min [BTM] vs 1768 min [no BTM], P = 0.044). Number of operations, allograft use, hospital and ICU LOS, and blood product use were similar between groups. Adjusted models accounting for TBSA supported unadjusted models.

CONCLUSION

Resource utilisation and clinical outcomes were similar in patients with at least 40 % TBSA treated with BTM and those who were treated with allograft before the introduction of BTM. Patients treated with BTM had significantly less total operative time and no difference in number of operations, allograft use and ICU LOS.

Design matters: A comparison of natural versus synthetic skin substitutes across benchtop and porcine wound healing metrics: An experimental study

Background and Aims

Skin substitutes, essential tools for helping close full thickness wounds with minimal scarring, are available in both collagen-based and synthetic polyurethane constructions. Here we explore fundamental differences between two frequently used skin substitutes and discuss how these differences may impact in vivo performance.

Methods

Polyurethane- and collagen-based matrices were characterized in vitro for pore size via scanning electron microscopy, hydrophobicity via liquid contact angle, conformability via bending angle, and biocompatibility via fibroblast and keratinocyte adhesion and proliferation. These matrices were then evaluated in a full-thickness excisional pig wound study followed by histological analysis. Statistical analysis was performed using t-tests or one-way analysis of variances with Tukey's multiple post hoc comparisons, where appropriate.

Results

Average pore diameter in the tested polyurethane matrix was over four times larger than that of the collagen matrix (589 ± 297 µm vs. 132 ± 91 µm). Through liquid contact angle measurement, the collagen matrix (not measurable) was found to be hydrophilic compared to the hydrophobic polyurethane matrix (>90°). The collagen matrix was significantly more conformable than the polyurethane matrix (9 ± 2° vs. 84 ± 5° bending angle, respectively). Fibroblast and keratinocyte adhesion and proliferation assays elucidated a significantly greater ability of both cell types to attach and proliferate on collagen versus polyurethane. While the porcine study showed minimal contraction of either matrix material, histological findings between the two treatments were markedly different. Collagen matrices were associated with early fibroblast infiltration and fibroplasia, whereas polyurethane matrices elicited a strong multinucleated giant cell response and produced a network of comparatively aligned collagen fibrils.

Conclusions

The more favorable in vitro properties of the collagen matrix led to less inflammation and better overall tissue response in vivo. Overall, our findings demonstrate how the choice of biomaterial and its design directly translate to differing in vivo mechanisms of action and overall tissue quality.

Burn Wound Bed Management

Critical to the success of modern burn care is the management of the burn wound. Timely and complete removal of nonviable tissue is complicated by the irreplaceable nature of the tissue lost either through the burn injury or as "collateral damage" as part of the treatment. Challenges in distinguishing between viable and nonviable tissue and "replacing the irreplaceable" are discussed alongside potential disruptive technologies which could fundamentally change how burn care is delivered. Advances in burn wound bed management forms the foundation on which the goal of zero preventable death and disability after burn injury can be achieved.

Reconstruction of a Near-total Scalp Avulsion with NovoSorb Biodegradable Temporizing Matrix: Pediatric Case Report

Traumatic dog bites of the face and head are common among the pediatric population, although injuries resulting in total or subtotal scalp avulsions are rare and life-threatening. Standard treatment in these cases includes attempts at replantation or free tissue transfer; however, these procedures may not always be possible. An alternative treatment option involves the use of dermal substitutes, such as Integra (Integra LifeScience Corporation), with subsequent skin grafting. More recently, an alternative skin substitute called NovoSorb Biodegradable Temporizing Matrix (BTM) (PolyNovo North America LLC) has displayed favorable reconstructive outcomes in recent burn literature. NovoSorb BTM is a novel, fully synthetic bilayer scaffold made of biodegradable polyurethane matrix covered with a sealing membrane. In this report, the authors describe a 3-year-old boy who presented emergently with a severe dog bite avulsion to the subpericranial level of approximately 80% of his scalp, which was not replantable. The surgical plan involved a staged reconstruction using Integra and later skin grafting. Purulent infection ensued and required removal of Integra less than 2 weeks from application. Upon clearing of the infection, the wound was successfully closed with BTM and subsequent skin grafting. With proper wound management and over 6 months of follow-up, the patient experienced excellent healing of the graft with stable calvarial coverage and an acceptable aesthetic outcome. He will undergo tissue expansion of the remaining hair-bearing scalp in the future.

Glycerolised skin allografts for extensive burns in low- and middle-income countries

Introduction:

There has been a significant improvement in the outcome of treatment of large surface area burns in developed countries. A major contributory factor is an early excision and skin grafting of burn wounds. The initial coverage of large surface area deep burn wounds requires the use of temporary skin substitutes such as allografts due to limited skin autografts. Cadaveric skin allografts are the commonest source of skin allografts in use; however, there may be religious, cultural, cost, or other factors mitigating its availability and routine use in low- and middle-income countries (LMICs). Human skin allografts may be used fresh or stored in tissue banks to ensure its ready availability. The purpose of this review is to promote glycerolised skin allografts as a means of skin preservation in low-resource countries above other modalities cryopreservation due to its cost advantages and relative ease of operation.

Materials and Methods:

A literature search for articles related to human skin allograft use in burn care, skin banks, and glycerolised skin allografts in LMICs was done using PubMed, EMBASE, and Web of Science databases. The key words used were ‘allograft’ and ‘burn’ with a filter in the search for human studies. The relevant references in the articles obtained were also searched for and included in the review

Results:

Sixty-three journal articles were reviewed for contents in line with the objectives of this study.

Conclusion:

Glycerolised skin graft is a viable option for coverage of extensive burns in LMICs.