Wound coverage technologies in burn care: novel techniques

Surgical Repair of the Acute Burn Wound: Who, When, What Techniques? What Is the Future?

Modern burns surgery is multidisciplinary, multimodal and includes a dermal preservation approach. The management of the surgical wound starts in the pre-hospital environment with stabilization and assessment of the burn injured patient according to protocols of trauma resuscitation with special emphasis in the assessment of the burn depth and surface area. A large burn requires fluid resuscitation and physiological support, including counterbalancing hyper metabolism, fighting infection and starting a long burns intensive care journey. A deep burn may impose the need for surgical debridement and cover through a staged approach of excision of devitalized tissue depending on its extension and patient circumstances. These methodologies warrant patients survivability and require professionals integrated in a multidisciplinary team sharing decisions and directing management. Burns Multimodality involves multiple techniques used according to patient's needs, wound environment, operators experience and available resources. Traditional practices used together with new techniques may reduce morbidity and operative time but also challenge stablished practice. The concept of using the best teams with the best techniques combines with the need for selective and judicious surgery that preserves tissue architecture and spares as much as possible dermal component, therefore reducing the possibility of functional impairment and cosmetic embarrassment caused by pathological scars. Who is best placed to perform these tasks, the appropriate or best timing of surgery and the different practices used to achieve best results will be discussed, together with a reflection on what the future holds for these fundamental steps in the management of the burn injured patient turning into a functional burn survivor.

Bioprinting and plastic compression of large pigmented and vascularized human dermo-epidermal skin substitutes by means of a new robotic platform

Extensive availability of engineered autologous dermo-epidermal skin substitutes (DESS) with functional and structural properties of normal human skin represents a goal for the treatment of large skin defects such as severe burns. Recently, a clinical phase I trial with this type of DESS was successfully completed, which included patients own keratinocytes and fibroblasts. Yet, two important features of natural skin were missing: pigmentation and vascularization. The first has important physiological and psychological implications for the patient, the second impacts survival and quality of the graft. Additionally, accurate reproduction of large amounts of patient’s skin in an automated way is essential for upscaling DESS production. Therefore, in the present study, we implemented a new robotic unit (called SkinFactory) for 3D bioprinting of pigmented and pre-vascularized DESS using normal human skin derived fibroblasts, blood- and lymphatic endothelial cells, keratinocytes, and melanocytes. We show the feasibility of our approach by demonstrating the viability of all the cells after printing in vitro, the integrity of the reconstituted capillary network in vivo after transplantation to immunodeficient rats and the anastomosis to the vascular plexus of the host. Our work has to be considered as a proof of concept in view of the implementation of an extended platform, which fully automatize the process of skin substitution: this would be a considerable improvement of the treatment of burn victims and patients with severe skin lesions based on patients own skin derived cells.

The Role of Skin Substitutes in Acute Burn and Reconstructive Burn Surgery: An Updated Comprehensive Review

Burns disrupt the protective skin barrier with consequent loss of cutaneous temperature regulation, infection prevention, evaporative losses, and other vital functions. Chronically, burns lead to scarring, contractures, pain, and impaired psychosocial well-being. Several skin substitutes are available and replace the skin and partially restore functional outcomes and improve cosmesis. We performed a literature review to update readers on biologic and synthetic skin substitutes to date applied in acute and reconstructive burn surgery. Improvement has been rapid in the development of skin substitutes in the last decade; however, no available skin substitute fulfills criteria as a perfect replacement for damaged skin.

Potential of Fibrin Glue and Mesenchymal Stem Cells (MSCs) to Regenerate Nerve Injuries: A Systematic Review

Cell-based therapy is a promising treatment to favor tissue healing through less invasive strategies. Mesenchymal stem cells (MSCs) highlighted as potential candidates due to their angiogenic, anti-apoptotic and immunomodulatory properties, in addition to their ability to differentiate into several specialized cell lines. Cells can be carried through a biological delivery system, such as fibrin glue, which acts as a temporary matrix that favors cell-matrix interactions and allows local and paracrine functions of MSCs. Thus, the aim of this systematic review was to evaluate the potential of fibrin glue combined with MSCs in nerve regeneration. The bibliographic search was performed in the PubMed/MEDLINE, Web of Science and Embase databases, using the descriptors ("fibrin sealant" OR "fibrin glue") AND "stem cells" AND "nerve regeneration", considering articles published until 2021. To compose this review, 13 in vivo studies were selected, according to the eligibility criteria. MSCs favored axonal regeneration, remyelination of nerve fibers, as well as promoted an increase in the number of myelinated fibers, myelin sheath thickness, number of axons and expression of growth factors, with significant improvement in motor function recovery. This systematic review showed clear evidence that fibrin glue combined with MSCs has the potential to regenerate nervous system lesions.

Skin regeneration is accelerated by a lower dose of multipotent mesenchymal stromal/stem cells-a paradigm change

Background

Multipotent mesenchymal stromal/stem cell (MSC) therapy is under investigation in promising (pre-)clinical trials for wound healing, which is crucial for survival; however, the optimal cell dosage remains unknown. The aim was to investigate the efficacy of different low-to-high MSC dosages incorporated in a biodegradable collagen-based dermal regeneration template (DRT) Integra®.

Methods

We conducted a porcine study (N = 8 Yorkshire pigs) and seeded between 200 and 2,000,000 cells/cm² of umbilical cord mesenchymal stromal/stem cells on the DRT and grafted it onto full-thickness burn excised wounds. On day 28, comparisons were made between the different low-to-high cell dose groups, the acellular control, a burn wound, and healthy skin.

Result

We found that the low dose range between 200 and 40,000 cells/cm² regenerates the full-thickness burn excised wounds most efficaciously, followed by the middle dose range of 200,000–400,000 cells/cm² and a high dose of 2,000,000 cells/cm². The low dose of 40,000 cells/cm² accelerated reepithelialization, reduced scarring, regenerated epidermal thickness superiorly, enhanced neovascularization, reduced fibrosis, and reduced type 1 and type 2 macrophages compared to other cell dosages and the acellular control.

Conclusion

This regenerative cell therapy study using MSCs shows efficacy toward a low dose, which changes the paradigm that more cells lead to better wound healing outcome.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-020-02131-6.

The use of biostatic human amnion and platelet-rich plasma in topical treatment of toxic epidermal necrolysis-A case report

BACKGROUND

Toxic epidermal necrolysis (TEN) (also known as Lyell syndrome) and Stevens-Johnson syndrome (SJS) are life-threatening mucocutaneous blistering diseases. They are characterized by generalized blisters and epidermal inflammation, most likely resulting from the administration or interaction of medicines.

AIMS

To report potential new method in the treatment of TEN.

PATIENTS/METHODS

This article presents a case report of a 35-year-old man suffering from TEN covering about 95% of his body surface. Lesions occurred in the patient during antiepileptic therapy, after taking simultaneously amoxicillin (with clavulanic acid) and naproxen followed by lamotrigine treatment. Standard general treatment was performed. Intravenous feeding was necessary. Due to acute respiratory failure, the patient required mechanical ventilation. Two methods were combined in topical treatment: application of platelet-rich plasma (PRP) and a simultaneous biostatic human amnion transplant.

RESULTS

In the presented case, the combination of both methods contributed to a significant acceleration of wound healing. After the application of PRP and biostatic amnion transplantation, the healing of wounds on the back and posterior surfaces of the legs was completed after six days. The surgical treatment most probably contributed to a significant acceleration of wound healing.

CONCLUSION

The case report shows that topical TEN/SJS treatment with biostatic human amnion and PRP has a positive clinical effect and may be a new method of treatment of TEN.

Use of haemostatic gel in the management of cervical pregnancy: a case report

PURPOSE

This case report aimed to describe haemostatic agents with systemic methotrexate (MTX) as an effective management for cervical pregnancy with bleeding.

CASE PRESENTATION

A 34-year-old nulligravida patient was referred due to vaginal spotting and lower abdominal discomfort, and was diagnosed with a cervical pregnancy at 6 weeks of gestation. The patient was treated with a multi-dose MTX regimen, and the bleeding was successfully controlled with haemostatic agents, which were applied at the bleeding site of the cervix. After completion of MTX treatment, beta human chorionic gonadotropin (β-hCG) decreased to undetectable range. Furthermore, patients could preserve her uterus and maintain fertility.

CONCLUSION

Haemostatic agents can be regarded as an effective option for vaginal bleeding due to cervical pregnancy.

Regulatory approval process for advanced dressings in India: an overview of rules

OBJECTIVE

There is a high rate of death due to burns and wound infections in India. Innovators and manufacturers of wound and burn dressings need to keep themselves abreast of the most current rules governing medical devices. The concept of advanced dressings is emerging in India. However, local manufacturing is hindered by an absence of clear regulatory guidelines. The lack of advanced wound and burn dressings on the market critically affects patient survival rates, while imports from other countries make dressings unaffordable and beyond the reach of most patients. This article presents the details of an approval procedure for advanced dressings and provides manufacturers, innovators and investors with a better understanding of the classification rules, import, export and marketing approval processes. We also discus the reasons for high levels of imports and costs, as well as suggestions on how to address this.

METHOD

A critical analysis was conducted of 54 research and review articles, including regulatory guidelines to control the marketing of wound and burn care dressings recommended by international regulatory agencies.

CONCLUSION

India is highly dependent on imports of advanced dressings. Due to lack of clear, quality regulatory guidelines, innovators and manufacturers are facing issues while showcasing their product in the Indian market. Thus development of clear quality regulatory guidelines is crucial. Therefore, this article may guide and encourage manufacturers to develop advanced dressings in India.

Burn injury

Burn injuries are under-appreciated injuries that are associated with substantial morbidity and mortality. Burn injuries, particularly severe burns, are accompanied by an immune and inflammatory response, metabolic changes and distributive shock that can be challenging to manage and can lead to multiple organ failure. Of great importance is that the injury affects not only the physical health, but also the mental health and quality of life of the patient. Accordingly, patients with burn injury cannot be considered recovered when the wounds have healed; instead, burn injury leads to long-term profound alterations that must be addressed to optimize quality of life. Burn care providers are, therefore, faced with a plethora of challenges including acute and critical care management, long-term care and rehabilitation. The aim of this Primer is not only to give an overview and update about burn care, but also to raise awareness of the ongoing challenges and stigmata associated with burn injuries.

Bioprinted Skin Recapitulates Normal Collagen Remodeling in Full-Thickness Wounds

Over 1 million burn injuries are treated annually in the United States, and current tissue engineered skin fails to meet the need for full-thickness replacement. Bioprinting technology has allowed fabrication of full-thickness skin and has demonstrated the ability to close full-thickness wounds. However, analysis of collagen remodeling in wounds treated with bioprinted skin has not been reported. The purpose of this study is to demonstrate the utility of bioprinted skin for epidermal barrier formation and normal collagen remodeling in full-thickness wounds. Human keratinocytes, melanocytes, fibroblasts, dermal microvascular endothelial cells, follicle dermal papilla cells, and adipocytes were suspended in fibrinogen bioink and bioprinted to form a tri-layer skin structure. Bioprinted skin was implanted onto 2.5 × 2.5 cm full-thickness excisional wounds on athymic mice, compared with wounds treated with hydrogel only or untreated wounds. Total wound closure, epithelialization, and contraction were quantified, and skin samples were harvested at 21 days for histology. Picrosirius red staining was used to quantify collagen fiber orientation, length, and width. Immunohistochemical (IHC) staining was performed to confirm epidermal barrier formation, dermal maturation, vascularity, and human cell integration. All bioprinted skin treated wounds closed by day 21, compared with open control wounds. Wound closure in bioprinted skin treated wounds was primarily due to epithelialization. In contrast, control hydrogel and untreated groups had sparse wound coverage and incomplete closure driven primarily by contraction. Picrosirius red staining confirmed a normal basket weave collagen organization in bioprinted skin-treated wounds compared with parallel collagen fibers in hydrogel only and untreated wounds. IHC staining at day 21 demonstrated the presence of human cells in the regenerated dermis, the formation of a stratified epidermis, dermal maturation, and blood vessel formation in bioprinted skin, none of which was present in control hydrogel treated wounds. Bioprinted skin accelerated full-thickness wound closure by promoting epidermal barrier formation, without increasing contraction. This healing process is associated with human cells from the bioprinted skin laying down a healthy, basket-weave collagen network. The remodeled skin is phenotypically similar to human skin and composed of a composite of graft and infiltrating host cells. Impact statement We have demonstrated the ability of bioprinted skin to enhance closure of full-thickness wounds through epithelialization and normal collagen remodeling. To our knowledge, this article is the first to quantify collagen remodeling by bioprinted skin in full-thickness wounds. Our methods and results can be used to guide further investigation of collagen remodeling by tissue engineered skin products to improve ongoing and future bioprinting skin studies. Ultimately, our skin bioprinting technology could translate into a new treatment for full-thickness wounds in human patients with the ability to recapitulate normal collagen remodeling in full-thickness wounds.

Risk of bias and reporting completeness of randomised controlled trials in burn care: protocol for a systematic review

INTRODUCTION

Burn care represents a healthcare and economic burden to patients internationally. Choice of the most clinically effective treatment strategies requires evidence which is best obtained through high-quality randomised controlled trials (RCT). The number of published RCTs of burn care is increasing. However, trial quality and reporting standards are unclear. This study will assess the risk of bias and adequacy of reporting in recent burn care RCTs using tools endorsed by the Cochrane Collaboration.

METHODS AND ANALYSIS

A systematic literature review will be undertaken, assessing parallel group RCTs evaluating therapeutic interventions for patients with cutaneous burns. Literature searches will use Ovid Medline, Ovid Embase, Web of Science and the Cochrane Library. Separate searches for each database will include medical subject heading and free text terms including 'burn', 'scald', 'thermal injury' and 'RCT'. Two reviewers will independently assess each study for inclusion. Risk of bias (RoB) will be assessed with the revised tool (RoB 2) and reporting completeness with the CONsolidated Standards of Reporting Trials (CONSORT) 2010 guidelines. We will report a narrative synthesis of all studies, including domain specific, and overall risk of bias for the primary outcome of each trial. Inter-rater agreement for RoB 2 will be reported using Fleiss's Kappa. For adherence to the CONSORT guidelines, we will generate a completeness of reporting index for the five domains.

ETHICS AND DISSEMINATION

No ethics approval is required because published documents will be used. Findings of the study will be disseminated in a peer-reviewed journal and presented at conferences.

PROSPERO REGISTRATION NUMBER

CRD42018111020.

Quantifying the effects of wound healing risk and potential on clinical measurements and outcomes of severely burned patients: A data-driven approach

INTRODUCTION

Given recent advances in computational power, the goal of this study was to quantify the effects of wound healing risk and potential on clinical measurements and outcomes of severely burned patients, with the hope of providing more insight on factors that affect wound healing.

METHODS

This retrospective study involved patients who had at least 10% TBSA% "burned" and three burn mappings each. To model risk to wounds, we defined the variable θ, a hypothetical threshold for TBSA% "open wound" used to demarcate "low-risk" from "high-risk" patients. Low-risk patients denoted those patients whose actual TBSA% "open wound" ≤θ, whereas high-risk patients denoted those patients whose actual TBSA% "open wound" >θ. To consider all possibilities of risk, 100 sub analyses were performed by (1) varying θ from 100% to 1% in decrements of 1%, (2) grouping all patients as either "low-risk" or "high-risk" for each θ, and (3) comparing all means and deviations of variables and outcomes between the two groups for each θ. Hence, this study employed a data-driven approach to capture trends in clinical measurements and outcomes. Plots and tables were also obtained.

RESULTS

For 303 patients, median age and weight were 43 [29-59] years and 85 [72-99]kg, respectively. Mean TBSA% "burned" was 25 [17-39] %, with a full-thickness burn of 4 [0-15] %. Average crystalloid volumes were 4.25±2.27mL/kg/TBSA% "burned" in the first 24h. Importantly, for high-risk patients, decreasing θ was matched by significant increases in PaO2-FiO2 ratio, platelet count, Glasgow coma score (GCS), and MAP. On the other hand, increasing their risk θ was also matched by significant increases in creatinine, bilirubin, lactate, blood, estimated blood loss, and 24-h and total fluid volumes. As expected, for low-risk patients, clinical measurements were more stable, despite decreasing or increasing θ. At a θ of 80%, statistical tests indicated much disparity between high-risk and low-risk patients for TBSA% "burned", full thickness burn, bilirubin (1.66±1.16mg/dL versus 0.83±0.65mg/dL, p=0.005), GCS (7±2 versus 12±3, p<0.001), MAP (42±22mm Hg versus 59±22mm Hg, p=0.004), 24-h blood, estimated blood loss, 24-h fluid, total fluid, and ICU length of stay (81±113 days versus 24±27 days, p=0.002). These differences were all statistically significant and remained significant down to θ=10%.

CONCLUSION

Wound healing risk and potential may be forecasted by many different clinical measurements and outcomes and has many implications on multi-organ function. Future work will be needed to further explain and understand these effects, in order to facilitate development of new predictive models for wound healing.

Relationship Between Burn Wound Location and Outcomes in Severely Burned Patients: More Than Meets the Size

We hypothesized that burn location plays an important role in wound healing, mortality, and other outcomes and conducted the following study to test this multifold hypothesis. We conducted a study to retrospectively look at patients with burns ≥10% TBSA. Demographics, TBSA, partial/full thickness burns (PT/FT) in various wound locations, fluids, inhalation injury, mortality, ICU duration, and hospital duration were considered. Initial wound healing rates (%/d) were also calculated as a slope from the time of the first mapping of open wound size to the time of the third mapping of open wound size. Multivariate logistic regression and operating curves were used to measure mortality prediction performance. All values were expressed as median [interquartile range]. The mortality rate for 318 patients was 17% (54/318). In general, patients were 43 years [29, 58 years] old and had a TBSA of 25% [17, 39%], PT of 16% [10, 25%], and FT of 4% [0, 15%]. Between patients who lived and did not, age, TBSA, FT, 24-hour fluid, and ICU duration were statistically different (P < .001). Furthermore, there were statistically significant differences in FT head (0% [0, 0%] vs 0% [0, 1%], P = .048); FT anterior torso (0% [0, 1%] vs 1% [0, 4%], P < .001); FT posterior torso (0% [0, 0%] vs 0% [0, 4%], P < 0.001); FT upper extremities (0% [0, 3%] vs 2% [0, 11%], P < .001); FT lower extremities (0% [0, 2%] vs 6% [0, 17%], P < .001); and FT genitalia (0% [0, 0%] vs 0% [0, 2%], P < .001). Age, presence of inhalation injury, PT/FT upper extremities, and FT lower extremities were independent mortality predictors and per unit increases of these variables were associated with an increased risk for mortality (P < .05): odds ratio of 1.09 (95% confidence interval [CI] = 1.61–1.13; P < .001) for mean age; 2.69 (95% CI = 1.04–6.93; P = .041) for inhalation injury; 1.14 (95% CI = 1.01–1.27; P = .031) for mean PT upper extremities; 1.26 (95% CI = 1.11–1.42; P < .001) for mean FT upper extremities; and 1.07 (95% CI = 1.01–1.12; P = .012) for mean FT lower extremities. Prediction of mortality was better using specific wound locations (area under the curve [AUC], AUC of 0.896) rather than using TBSA and FT (AUC of 0.873). Graphs revealed that initial healing rates were statistically lower and 24-hour fluids and ICU length of stay were statistically higher in patients with FT upper extremities than in patients without FT extremities (P < .001). Burn wound location affects wound healing and helps predict mortality and ICU length of stay and should be incorporated into burn triage strategies to enhance resource allocation or stratify wound care.

Flowable Polyethylene Glycol Hydrogels Support the in Vitro Survival and Proliferation of Dermal Progenitor Cells in a Mechanically Dependent Manner

Cell-based therapies have garnered considerable interest largely because of their potential utility for tissue regeneration in a variety of organs, including skin. Designing vehicles that enable optimal delivery and purposeful integration of donor cells within tissues will be critical for their success. Here, we investigate the utility of an injectable, self-polymerizing, fully synthetic hydrogel in supporting the survival, proliferation, and function of cultured adult dermal progenitor cells (DPCs) which may serve as a source of renewable cells to repair severe skin injuries or restore hair growth. We show that modifying the stiffness of these transglutaminase cross-linked poly(ethylene glycol) (TG-PEG) hydrogels significantly alters DPC behavior and phenotype; increasing stiffness promotes their differentiation and migration whereas softer gels maintained them in a proliferative state. We found that 2-3% TG-PEG was optimal to promote cell expansion and survival. Unexpectedly, DPCs grown in all conditions maintained their inductive function and thus generated de novo hair follicles. Our data suggests that TG-PEG hydrogels may be a versatile platform for stem and progenitor cell transplantation and fate specification while maintaining functional competence.

Use of Fibrin Sealant for Split-Thickness Skin Grafts in Patients with Hand Burns: A Prospective Cohort Study

OBJECTIVE

To evaluate the efficacy of fibrin sealant as a topical hemostatic agent and for graft fixation during skin grafting of hand burns.

METHODS

This prospective cohort study enrolled 40 patients with hand burns from January 2013 to December 2016. They were all treated with excision and split-thickness skin graft and divided into the fibrin sealant with tourniquet group (20 patients) and epinephrine tumescence group (20 patients).

MAIN OUTCOME MEASURES

Demographic and clinical data such as age, sex, burn characteristics, operation time, estimated blood loss, and take rate were collected from each patient.

MAIN RESULTS

The demographic and burn characteristics were not statistically different between the two groups. Estimated blood loss per cm (0.30 vs 1.00; P < .001) was significantly lower and the graft take rate (99.2% vs 98.2%; P = .032) was significantly higher in the fibrin sealant with tourniquet group.

CONCLUSIONS

The use of fibrin sealants accompanied by tourniquets for hand burns exhibited superior results in terms of decreasing blood loss and had a better graft take rate compared with treatment with epinephrine tumescence.

Ethanol and Methanol Burn Risks in the Home Environment

Biofuel heaters and fireplaces have in recent years been introduced for indoor and outdoor use. Due to their simplicity, they are usually equipped with few or no safety features. Worldwide, incidents resulting in major skin burn injury and long hospitalization periods have occurred when using such biofuel units. The present study analyses the characteristics of the liquids ethanol and methanol to get a scientific background for understanding related accidents. The comparably heavy vapors, especially from ethanol, may generate a pillow of combustible gas in the vicinity of the unit, particularly in quiescent indoor air conditions. It is also revealed that these fuels represent a potential severe risk, since the equilibrium vapor pressures are close to the stoichiometric fuel–air composition at normal room temperatures. Selected incidents were reviewed to understand the mechanisms involved when severe burns were received by the users. It turns out that the most severe incidents were related to refilling operations and included ignition of the fuel container vapor phase. When ignited, the container gas phase expansion propelled burning fuel from the bottle or container onto the user or other persons in the vicinity. Similar incidents involving refilling methanol for chemistry demonstrations and ethanol for endodontic (dentistry) treatment were also studied and it was shown that these accidents followed similar accident mechanisms. It may be concluded that the main contributors to burn risk are the near-stoichiometric vapor pressure of these liquids at room temperature and the close proximity of the fuel container to burning fuel. Research needs and possible technical barriers are suggested to reduce this risk for the future.

Healing after Resection of Colonic Endometriosis and Growth Factor-enriched Agents: An Experimental Rat Model

STUDY OBJECTIVE

To examine the potential beneficial effect of platelet-rich plasma (PRP) and fibrin sealant (TISSEEL; Baxter Healthcare Corporation, Deerfield, IL) on bowel wound healing after shaving of an experimentally induced endometriotic lesion.

DESIGN

A single-blind, randomized study (Canadian Task Force classification I).

SETTING

A certified animal research facility.

ANIMALS

Thirty female Sprague-Dawley rats.

INTERVENTIONS

Experimental colonic endometriosis was induced by transplanting endometrial tissue to all animals (first surgery). Thirty rats were then randomized to 1 of 3 groups according to treatment; PRP (group 1, n = 10), fibrin sealant (group 2, n = 10), or no agent (group 3, n = 10) was applied after shaving of the endometriotic nodule (second surgery).

MEASUREMENTS AND MAIN RESULTS

Colonic endometriosis was successfully induced in all subjects. Four days after the second surgery, the animals were euthanized, and microscopic evaluation was performed. The pathologist was blinded to the treatment method. Histopathologic analysis revealed that compared with the control group, collagen disposition was found in a significantly higher expression in both the PRP and fibrin sealant groups (p = .011 and p = .011, respectively). Distortion of the integrity of the colon layers was statistically more pronounced in the control group compared with the fibrin sealant group (p = .033), whereas greater new blood vessel formation was observed in the fibrin sealant group compared with the control (p = .023). No histologic evidence of residual or recurrent disease was detected.

CONCLUSION

Both PRP and fibrin sealant appear to be safe and associated with improved tissue healing during shaving for the excision of colonic endometriosis, attributed to the enhanced collagen disposition, neovascularization, and protection of the integrity of colon layers. Clinical trials are warranted to confirm the feasibility of PRP and fibrin sealant in the clinical setting.

Delivery of Allogeneic Adipose Stem Cells in Polyethylene Glycol-Fibrin Hydrogels as an Adjunct to Meshed Autografts After Sharp Debridement of Deep Partial Thickness Burns

Harvesting of autografts results in donor site morbidities and is limited in scenarios such as large total body surface area burns. In these instances, coverage is increased by meshing grafts at the expense of delayed biologic closure. Moreover, graft meshing increases the likelihood of contraction and hypertrophic scarring, limits range of motion, and worsens cosmesis. Many tissue engineering technologies have touted the promise of adipose‐derived stem cells (ASCs) for burn wounds. The primary objective of the current study was to determine feasibility and efficacy of in situ ASC delivery via PEGylated fibrin (FPEG) hydrogels as adjuncts to meshed split thickness skin grafts in a porcine model. Deep partial thickness burns were created on the dorsum of anesthetized Yorkshire pigs, and subsequently debrided on post‐burn day 4. After debridement, wounds were treated with: split thickness skin grafts (STSG); meshed STSG (mSTSG); and mSTSG + FPEG with increasing doses of ASCs. We show that FPEG hydrogels can be delivered in situ to prevent the contraction seen after meshing of STSG. Moreover, ASCs delivered in FPEG dose‐dependently increase blood vessel size which significantly correlates with CD31 protein levels. The current study reports a dual‐action adjunct therapy to autografting administered in situ, wherein FPEG acts as both scaffolding to prevent contraction, and as a delivery vehicle for ASCs to accelerate angiogenesis. This strategy may be used to incorporate other biologics for generating tissue engineered products aimed at improving wound healing and minimizing donor sites or scarring. stemcellstranslationalmedicine2018;7:360–372

Glucose Control in Severely Burned Patients Using Metformin: An Interim Safety and Efficacy Analysis of a Phase II Randomized Controlled Trial

OBJECTIVE

To determine whether metformin can achieve glucose control no worse than insulin (noninferiority) without the danger of hypoglycemia (superiority). In addition, to assess whether metformin has any additional effects on lipolysis and inflammation that will enhance burn recovery (superiority).

SUMMARY BACKGROUND DATA

Hyperglycemia and insulin resistance after burn injury are associated with increased morbidity and mortality. Insulin administration improves postburn infections, severity of sepsis, and morbidity, but also causes a 4-5-fold increase in hypoglycemia, which is associated with a 9-fold increase in mortality.

METHODS

Severely burned adult patients with burns over 20% total body surface area (TBSA) burn were prospectively randomized in this Phase II clinical trial to either metformin or insulin (standard of care) treatment. Primary outcomes were glucose levels and incidence of hypoglycemia. Secondary outcomes included glucose and fat metabolism, and clinical outcomes.

RESULTS

Forty-four patients were enrolled in this Phase II clinical trial, 18 metformin and 26 insulin patients. Demographics, burn size, concomitant injuries, and mortality were comparable between both groups. Metformin controlled blood glucose as equally as insulin with no difference between the 2 treatment groups, P > 0.05. While there was a 15% incidence of hypoglycemia in the insulin group, there was only 1 mild hypoglycemic episode (6%) in the metformin group, P < 0.05. Oral glucose tolerance tests at discharge revealed that metformin significantly improved insulin sensitivity, P < 0.05. Furthermore, metformin had a strong antilipolytic effect after burn injury when compared with insulin and was associated with significantly reduced inflammation, P < 0.05.

CONCLUSIONS

Metformin decreases glucose equally as effective as insulin without causing hypoglycemia, with additional benefits including improved insulin resistance and decreased endogenous insulin synthesis when compared with insulin controls. These results indicate that metformin is safe in burn patients and further supports the use of metformin in severely burned patients for postburn control of hyperglycemia and insulin resistance.

[Surgical treatment of burns : Special aspects of pediatric burns]

BACKGROUND

Treatment of pediatric burn patients is very important because of the sheer frequency of burn wounds and the possible long-term ramifications. Extensive burns need special care and are treated in specialized burn centers.

OBJECTIVES

The goal of this work is to present current standards in burn therapy and important innovations in the treatment of burns in children so that the common and small area burn wounds and scalds in pediatric patients in day-to-day dermatological practice can be adequately treated.

MATERIALS AND METHODS

Analysis of current literature, discussion of reviews, incorporation of current guidelines.

RESULTS

Burns in pediatric patients are common. Improvement of survival can be achieved by treatment in burn centers. The assessment of burn depth and area is an important factor for proper treatment. We give an overview for outpatient treatment of partial thickness burns. New methods may result in better long-term outcome.

CONCLUSIONS

Adequate treatment of burn injuries considering current literature and guidelines improves patient outcome. Rational implementation of new methods is recommended.

Fumarate-loaded electrospun nanofibers with anti-inflammatory activity for fast recovery of mild skin burns

In the biomedical sector the availability of engineered scaffolds and dressings that control and reduce inflammatory states is highly desired, particularly for the management of burn wounds. In this work, we demonstrate for the first time, to the best of our knowledge, that electrospun fibrous dressings of poly(octyl cyanoacrylate) (POCA) combined with polypropylene fumarate (PPF) possess anti-inflammatory activity and promote the fast and effective healing of mild skin burns in an animal model. The fibers produced had an average diameter of (0.8  ±  0.1) µm and they were able to provide a conformal coverage of the injured tissue. The application of the fibrous mats on the burned tissue effectively reduced around 80% of the levels of pro-inflammatory cytokines in the first 48 h in comparison with un-treated animals, and enhanced skin epithelialization. From histological analysis, the skin thickness of the animals treated with POCA : PPF dressings appeared similar to that of one of the naïve animals: (13.7  ±  1.4) µm and (14.3  ±  2.5) µm for naïve and treated animals, respectively. The density of dermal cells was comparable as well: (1100  ±  112) cells mm(-2) and (1358  ±  255) cells mm(-2) for naïve and treated mice, respectively. The results demonstrate the suitability of the electrospun dressings in accelerating and effectively promoting the burn healing process.

Retrospective review of a tertiary adult burn centre's experience with modified Meek grafting

Background

Autologous split skin grafting is the gold standard in treating patients with massive burns. However, the limited availability of donor sites remains a problem. The aim of this study is to present our experience with the modified Meek technique of grafting, outcomes achieved and recommendations for optimized outcomes.

Methods

We retrospectively reviewed patient records from our tertiary referral burn centre and the Bi-National Burns Registry to identify all patients who had modified Meek grafting between 2010 and 2013. Patient records were reviewed individually and information regarding patient demographics, mechanism of injury and surgical management was recorded. Outcome measures including graft take rate, requirement for further surgery and complications were also recorded.

Results

Eleven patients had modified Meek grafting procedures. The average age of patients was 46 years old (range 23 – 64). The average total body surface area (TBSA) burnt was 56.75 % (range 20–80 %). On average, 87 % of the grafted areas healed well and did not require regrafting. In the regrafted areas, infection was the leading cause of graft failure.

Conclusions

Modified Meek grafting is a useful method of skin expansion. Similar to any other grafting technique, infection needs to be sought and treated promptly. It is recommended for larger burns where donor sites are not adequate or where it is desirable to limit their extent.

Debridement Techniques in Pediatric Trauma and Burn-Related Wounds

Significance: Traumatic injuries are the leading cause of morbidity and mortality in children. The purpose of this review is to provide an overview of the initial assessment and management of traumatic and burn wounds in children. Special attention is given to wound cleansing, debridement techniques, and considerations for pain management and psychosocial support for children and families. Recent Advances: Basic and translational research over the last 5-7 years has advanced our knowledge related to the optimal care of acute pediatric traumatic and burn wounds. Data concerning methods, volume, solution and timing for irrigation of acute traumatic wounds, timing and methods of wound debridement, including hydrosurgery and plasma knife coblation, and wound dressings are presented. Additionally, data concerning the long-term psychosocial outcomes following acute injury are presented. Critical Issues: The care of pediatric trauma and burn-related wounds requires prompt assessment, pain control, cleansing, debridement, application of appropriate dressings, and close follow-up. Ideally, a knowledgeable multidisciplinary team cares for these patients. A limitation in the care of these patients is the relative paucity of data specific to the care of acute traumatic wounds in the pediatric population. Future Directions: Research is ongoing in the arenas of new debridement techniques and instruments, and in wound dressing technology. Dedicated research on these topics in the pediatric population will serve to strengthen and advance the care of pediatric patients with acute traumatic and burn wounds.

Meta-analysis of randomized trials comparing nonpenetrating vs mechanical mesh fixation in laparoscopic inguinal hernia repair

BACKGROUND

Evidence for open groin hernia repair demonstrates less pain with bioglue mesh fixation compared with invasive methods. This study aimed to assess the short- and long-term effects of laparoscopic groin hernia repair with noninvasive and invasive mesh fixation.

DATA SOURCES

A systematic review of MEDLINE, CENTRAL, and OpenGrey was undertaken. Randomized trials assessing the outcome of laparoscopic groin hernia repair with invasive and noninvasive fixation methods were considered for data synthesis. Nine trials encompassing 1,454 patients subjected to laparoscopic hernia repair with mesh fixation using biologic or biosynthetic glue were identified. Short-term data were inadequate for data synthesis. Chronic pain was less frequently reported by patients subjected to repair with biologic glue fixation than with penetrating methods (odds ratio .46, 95% confidence interval .22 to .93). Duration of surgery, incidence of seroma/hematoma, morbidity, and recurrence were similar.

CONCLUSIONS

Laparoscopic groin hernia repair with bioglue mesh fixation was associated with a reduced incidence of chronic pain compared with mechanical fixation, without increasing morbidity or recurrence. Longer term data on recurrence are necessary.

Burn wound healing and treatment: review and advancements

Burns are a prevalent and burdensome critical care problem. The priorities of specialized facilities focus on stabilizing the patient, preventing infection, and optimizing functional recovery. Research on burns has generated sustained interest over the past few decades, and several important advancements have resulted in more effective patient stabilization and decreased mortality, especially among young patients and those with burns of intermediate extent. However, for the intensivist, challenges often exist that complicate patient support and stabilization. Furthermore, burn wounds are complex and can present unique difficulties that require late intervention or life-long rehabilitation. In addition to improvements in patient stabilization and care, research in burn wound care has yielded advancements that will continue to improve functional recovery. This article reviews recent advancements in the care of burn patients with a focus on the pathophysiology and treatment of burn wounds.

Uncultured adipose-derived regenerative cells (ADRCs) seeded in collagen scaffold improves dermal regeneration, enhancing early vascularization and structural organization following thermal burns

OBJECTIVE

Advances in tissue engineering have yielded a range of both natural and synthetic skin substitutes for burn wound healing application. Long-term viability of tissue-engineered skin substitutes requires the formation and maturation of neo-vessels to optimize survival and biointegration after implantation. A number of studies have demonstrated the capacity of Adipose Derived Regenerative Cells (ADRCs) to promote angiogenesis and modulate inflammation. On this basis, it was hypothesized that adding ADRCs to a collagen-based matrix (CBM) (i.e. Integra) would enhance formation and maturation of well-organized wound tissue in the setting of acute thermal burns. The purpose of this study was to evaluate whether seeding uncultured ADRCs onto CBM would improve matrix properties and enhance healing of the grafted wound.

METHODS

Full thickness thermal burns were created on the backs of 8 Gottingen mini-swine. Two days post-injury wounds underwent fascial excision and animals were randomized to receive either Integra seeded with either uncultured ADRCs or control vehicle. Wound healing assessment was performed by digital wound imaging, histopathological and immunohistochemical analyses.

RESULTS

In vitro analysis demonstrated that freshly isolated ADRCs adhered and propagated on the CBM. Histological scoring revealed accelerated maturation of wound bed tissue in wounds receiving ADRCs-loaded CBM compared to vehicle-loaded CBM. This was associated with a significant increase in depth of the wound bed tissue and collagen deposition (p<0.05). Blood vessel density in the wound bed was 50% to 69.6% greater in wounds receiving ADRCs-loaded CBM compared to vehicle-loaded CBM (p=0.05) at day 14 and 21. In addition, ADRCs delivered with CBM showed increased blood vessel lumen area and blood vessel maturation at day 21(p=0.05). Interestingly, vascularity and overall cellularity within the CBM were 50% and 45% greater in animals receiving ADRC loaded scaffolds compared to CBM alone (p<0.05).

CONCLUSIONS

These data demonstrate that seeding uncultured ADRCs onto CBM dermal substitute enhances wound angiogenesis, blood vessel maturation and matrix remodeling.