Development of a cellular assay as a personalized model for testing chronic wound therapeutics.

Exudates of non-healing wounds contain drivers of pathogenicity. We utilized >800 exudates from non-healing and healing wounds of diverse etiologies, collected by three different methods, to develop a wound-specific, cell-based functional biomarker assay. Human dermal fibroblast proliferation served as readout to a) to differentiate between healing and non-healing wounds, b) follow the healing process of individual patients, and c) assess the effects of therapeutics for chronic wounds ex vivo. We observed a strong correlation between wound chronicity and inhibitory effects of individual exudates on fibroblast proliferation, with good diagnostic sensitivity (76-90%, depending on the sample collection method). Transition of a clinically non-healing to a healing phenotype restored fibroblast proliferation and extracellular matrix formation while reducing inflammatory cytokine production. Transcriptional analysis of fibroblasts exposed to ex vivo non-healing wound exudates revealed an induction of inflammatory cytokine- and chemokine pathways and the unfolded protein response, indicating that these changes may contribute to the pathology of non-healing wounds. Testing the wound therapeutics platelet derived growth factor and silver sulfadiazine yielded responses in line with clinical experience and indicate the usefulness of the assay to search for and profile new therapeutics.

Management of Severe Burn Wounds Colonized With Multi-resistant Pseudomonas aeruginosa and Fusarium Using Marine Omega3 Wound Matrix in a Female Victim of War.

War-related burns are common injuries, also among the civilian population. Additional trauma such as fractures or shrapnel wounds may add significant morbidity. Burn injuries in war zones are furthermore frequently undertreated and hence prone to complications. We report a case of a young female victim of war, whose severely infected burn wounds could be successfully healed using a combination of targeted antimicrobial therapy, wound conditioning using decellularized fish skin, and subsequent skin grafting.

Regenerative Therapies for Basal Thumb Arthritis-A Systematic Review.

Basal thumb arthritis is a painful and debilitating pathology that can severely reduce a patients' quality of life. Common therapies include oral pain control, local steroid injections and/or surgery. Yet, therapeutic data on long-term improvement and even cartilage repair are scarce. This review aims to present the currently available literature on novel therapies for basal thumb arthritis, including platelet-rich plasma (PRP), fat grafting and phototherapy, and investigate their potential efficacy. The entire OVID database and PubMed were searched for studies containing the topics PRP injection, lipofilling, laser treatment and regenerative treatment for carpometacarpal arthritis. Seven studies on the effect of fat tissue on basal thumb arthritis were found. Four authors reported on PRP injections, one RCT examined a combinational treatment of PRP and fat grafting, another phototherapy for the thumb joint and one prospective trial on chondrocyte transplantation was found. Pain improvement and decreased impairment were reported in the majority of PRP and/or fat grafting studies as well as after chondrocyte implantation. Phototherapy did not significantly improve the condition. This review revealed that only limited data on regenerative therapies for carpometacarpal arthritis are currently available, yet PRP and lipofilling show promising results and merit further investigation.

Do Sex-Specific Factors Influence the Surgical Treatment of Facial Skin Cancer?

Facial skin cancer (FSC) is prone to incomplete excision due to the sophisticated anatomy and the aesthetic importance of the face. In this study, we sought to investigate to what extent sex-specific differences and other operation-, patient-, and cancer-specific factors influence the re-resection rate in FSC surgery, in order to provide personalized treatment strategies to patients. In this retrospective study, patients (>18 years) undergoing surgical excision of an FSC were enrolled. Each patient's demographic data, cancer location, the surgical team, primary and secondary surgeries were analyzed. Overall, 469 patients (819 surgeries) were included. The mean age was 69 ± 15 years. No significant association between sex-specific factors (surgeon's sex (OR: 1.09, 95% CI: 0.76-1.56) or patient's sex (OR: 0.85, 95% CI: 0.62-1.17), surgeon-patient sex concordance and discordance) and the likelihood of secondary surgery were found. However, healing by secondary intention (OR: 4.28; 95% CI: 1.94-9.45) and cancer location showed an increased re-resection rate. In conclusion, FSC surgery is a safe method unaffected by sex-specific factors, which had no impact on the re-resection rate. However, in further analysis, the likelihood of a re-resection was influenced by other factors such as healing by secondary intention and cancer location. This knowledge might be useful to provide an algorithm for personalized treatment strategies in the future.

Undergraduate Skills Training in Pandemic Times: Where Is the Future of Medical Education?

BACKGROUND: The COVID-19 pandemic forced medical programs to rapidly switch to remote teaching from scratch, impacting hands-on skills training. This study compared the efficacy of a hybrid online format to a regular in-person session for a mandatory surgical skills class. METHODS: Third-year undergraduate medical students attending the surgical skills class in the winter semester of 2020/21 at the Medical University of Graz were randomly assigned to either the hybrid or in-person class, depending on their course schedule and government regulations. The hybrid class involved online videos, one-on-one peer tutoring, and an Objective Structured Clinical Examination (OSCE). Pre- and post-class self-assessments were conducted to evaluate their theoretical and practical knowledge of a single interrupted suture. RESULTS: The study included 85 students in the regular in-person class and 50 in the hybrid class. A pre-class assessment revealed higher self-assessments in the hybrid class for theoretical and practical knowledge, but a post-class assessment showed no significant difference. The advantages and disadvantages of both modalities were identified, providing valuable insights for future curriculum development. CONCLUSIONS: Both teaching modes were effective for undergraduate surgical skills training. This study recommends implementing positive aspects of both the hybrid and in-person formats while recognizing their respective limitations.

Radiological Influencing Factors in the Diagnosis of Painful Habitual Instability of the Thumb Basal Joint as a Precursor of Carpometacarpal Arthritis of the Thumb-A Retrospective Study.

BACKGROUND: Painful habitual instability of the thumb basal joint (PHIT) is a rarely diagnosed condition that can severely impair hand function. Furthermore, it can increase the risk of developing carpometacarpal arthritis of the thumb (CMAOT). Clinical examination and radiographic imaging provide the foundation for a correct diagnosis, but early detection is still challenging. We investigated two objective, radiographically obtainable parameters as potential risk factors for PHIT. METHODS: Clinical data and radiographic images of 33 patients suffering from PHIT were collected and compared to those of 35 people serving as the control group. The two main objectives, the slope angle and the bony offset of the thumb joint, were gathered from the X-rays and statistically analyzed. RESULTS: The analysis showed no differences between the study and the control group concerning the slope angle. Gender and the bony offset, on the other hand, had a significant influence. Female sex and higher offset values were associated with an increased risk of PHIT. CONCLUSIONS: The results of this study prove a connection between a high bony offset and PHIT. We believe this information can be valuable in early detection and will allow more efficient treatment of this condition in the future.

Human In Vitro Skin Models for Wound Healing and Wound Healing Disorders.

Skin wound healing is essential to health and survival. Consequently, high amounts of research effort have been put into investigating the cellular and molecular components involved in the wound healing process. The use of animal experiments has contributed greatly to the knowledge of wound healing, skin diseases, and the exploration of treatment options. However, in addition to ethical concerns, anatomical and physiological inter-species differences often influence the translatability of animal-based studies. Human in vitro skin models, which include essential cellular and structural components for wound healing analyses, would improve the translatability of results and reduce animal experiments during the preclinical evaluation of novel therapy approaches. In this review, we summarize in vitro approaches, which are used to study wound healing as well as wound healing-pathologies such as chronic wounds, keloids, and hypertrophic scars in a human setting.

The perception of plastic surgery during the COVID-19 pandemic-an analysis of online search patterns on a medical information platform.

In 2020, the COVID-19 pandemic impacted global life and transitioned economies and societal perceptions of life as we knew it. Professional and social life mostly ground to a nadir during the first lockdown in Europe in March. As a consequence, measures aimed at preventing the spread of the virus were established in medical facilities also and elective plastic surgery procedures were temporarily suspended in our clinic and others. A majority of the population, including those potentially contemplating plastic surgery procedures, spent most of their time at home with ample time available to research information about surgical procedures and other topics online. This investigation analyzes the relevance of plastic surgery during the pandemic on the basis of online search behavior patterns. Online traffic data from the online platform http://www.mooci.org were extracted using Google Analytics over a period of 6 months. The parameters analyzed were: pageviews, session duration, and bounce rate. Additionally, differentiation by areas of interest has been obtained. The data were compared and analyzed before and after the beginning of the first hard lockdown in Austria, Germany, and Switzerland. There were no significant differences in regard to pageviews and session duration when comparing time points before and after the beginning of the hard lockdown. The bounce rate exhibited a significant decrease after the beginning of the lockdown, implying a more conscious search for information and greater absorption and retention. There was no difference that could conclusively be attributed to the pandemic in terms of specific areas of interest researched. Society's demand for information about plastic-surgical procedures continues to be steadily prevalent-despite, or even in particular, during a global pandemic. Providing reliable and readily available information about plastic surgery procedures is an important component of a functioning doctor-patient relationship and informed consent. This information may reflect society's increased interest in plastic surgery during the pandemic, or be simply reflective of more spare time at hand to allow for such research. Further studies should investigate the relevance of elective procedures over the entire course of the pandemic.

Does Electrical Stimulation through Nerve Conduits Improve Peripheral Nerve Regeneration?-A Systematic Review.

BACKGROUND: Peripheral nerve injuries affect over 2% of trauma patients and can lead to severe functional impairment and permanent disability. Autologous nerve transplantation is still the gold standard in the reconstruction of nerve defects. For small defects, conduits can be considered for bridging. Lately, the combined use of conduits and electrical stimulation has gained attention in the treatment of peripheral nerve injury. This review aimed to present the currently available data on this topic. METHODS: PubMed, Embase, Medline and the Cochrane Library were searched for studies on electrical stimulation through nerve conduits for nerve defects in in vivo studies. RESULTS: Fifteen studies fit the inclusion criteria. All of them reported on the application of nerve conduits combined with stimulation for sciatic nerve gaps in rats. Functional, electrophysiological and histological evaluations showed improved nerve regeneration after electrical stimulation. High variation was observed in the treatment protocols. CONCLUSION: Electrically stimulated conduits could improve peripheral nerve regeneration in rat models. The combined application of nerve guidance conduits and electrical stimulation shows promising results and should be further evaluated under standardized conditions.

Introducing the "SIMline"-A Simulation Course in the Management of Severe Burns as a Tool in Undergraduate Medical Education.

Background: Management of burn injuries presents a complex and challenging situation for medical staff, especially for inexperienced young doctors. However, training on how to treat burn victims in the clinical setting is rarely taught in undergraduate medical classes. We have created the "SIMline", a simulation training program explicitly designed for coaching medical students in burn management. Methods: A total of 43 students participated in the "SIMline" course, which took place at the training facility at the Medical University of Graz, between 2018 and 2019. The course provided theoretical classes, practical exercises, and a full-scale care process simulation training. The learning progress of the students was monitored via a formative integrated test. Results: Students showed great progress throughout the course of the "SIMline" program, as their test scores improved by an average of 88%. The passing rate was 0% at the first exam (prior to course) as compared to 87% at the final exam, taken after the training. Conclusions: Comprehensive practical training programs in burn care are underrepresented in medical education. The "SIMline" course presents a novel and effective approach in training medical students in burn management. However, follow-up evaluation is necessary to confirm long-term educational benefits.

The Impact of Thermal Stress on Cognition and the Use of Cooling Wear for Alleviation-An Explorative Study.

Increased ambient temperatures during the care of severely burned patients are essential for mitigating hypothermia and minimizing the impact of consecutive hypermetabolism. For involved medical staff, those conditions may lead to impaired concentration, possibly negatively affecting optimal patient care. Yet, alleviation strategies are lacking. As a novel coping strategy, cooling wear may be an effective means. This explorative study aimed to investigate the effect of high ambient temperatures on the concentration capacity and cooling wear to alleviate thermal stress. The effects of high ambient temperatures and the additional use of cooling wear on the concentration capacity of medical staff were investigated in six subjects during two simulated burn surgeries. Each individual served as his/her own control undergoing one simulation with and one without cooling wear. Concentration capacity was measured before and after each simulation with a standardized test. The results suggested that high ambient temperatures, as used in burn medicine, negatively affect human concentration capacity. The initial assessment of concentration capacity yielded homogenous values. After heat exposure, subjects wearing cooling wear showed a higher concentration capacity and a lower error rate compared to subjects without cooling wear. Summing up, temperature-related decrements in vigilance and performance among medical personnel may impair the patients' outcome. As an opportunity to withstand thermal stress and improve medical care and safety, cooling wear showed promising results and may be used as a heat alleviator. Burn medicine may particularly benefit from further development and rigorous investigation of cooling strategies.

Epidemiology of burn injury and the ideal dressing in global burn care - Regional differences explored.

PURPOSE: Burn injuries are to this day a major cause of morbidity and mortality, especially within low- and middle-income countries. Understanding the etiology of burn injury and epidemiologic- and hospital-specific factors associated with burns is vital for allotting resources for prevention and treatment. Therefore, the purpose of this study was to develop a profile of epidemiological differences in burn care and the ideal burn dressing among the different continents based on a global online survey. OBJECTIVES: This analysis evaluated trends in demographics, epidemiology of burn care, burn incidence, infection, related mortality and burn treatment (e.g., dressing changes and materials). The objective of this study was to investigate and compare the epidemiological profile of burn injury/care amongst the continents and a global control group to determine their utility for guiding evidence-based burn care and identify differences and/or similarities in their clinical practice. METHODS: A retrospective analysis of data was performed that was acquired during a previous study investigating the ideal burn dressing on a global perspective. The data was analyzed depending on the continent, on which the respondent indicated their hospital to be (Africa, Australia & New Zealand, Asia, Europe, Middle and South America, North America). Statistical analysis was performed to evaluate patient and hospital demographics and variables associated with burn injuries and their treatment. Outcomes of interest also included infections, mortality, length of stay on the ICU and important burn dressing characteristics. RESULTS: Healthcare providers in different areas of the world share similar views and needs regarding burn care management and on what constitutes an ideal burn dressing. We found significant differences in the various continents regarding hospitalization and length of stay on the ICU, with Australia taking the lead. Africa, with a high proportion of low-income-countries, reported the highest rate of burn infections, mortality, and a disproportionally high number of burn incidences amongst children. In general, men were mostly obtaining burn injuries amongst all continents. We found no significant differences regarding the most important characteristics of an ideal burn dressing. CONCLUSION: Our results suggest significant epidemiological differences regarding burn injuries and care amongst the continents, possibly resulting from the different infrastructure and/or circumstances on the various continents. Future scientific studies need to focus on adequate pain management and designing longer lasting materials that contain the "ideal" properties, by also taking individual regional needs/desires and the patient's perspective and economic boundaries into account. This analysis has delivered valuable insights into the epidemiological differences and/or similarities amongst the various continents.

Autologous Fat and Platelet-Rich Plasma Injections in Trapeziometacarpal Osteoarthritis: A Systematic Review and Meta-Analysis.

BACKGROUND: For the treatment of carpometacarpal arthritis of the thumb, various therapies are used. Infiltration therapy with autologous substances such as platelet-rich plasma and autologous fat have recently gained increasing attention because of beneficial pain-reducing effects in arthritis and the associated regenerative potential. However, the extent of clinical evidence in this area and how well autologous substances work in terms of pain reduction and improvements in hand function remain unclear. METHODS: A systematic review and meta-analysis were conducted to evaluate the current evidence and to provide more insight into pain reduction and improvement in hand function after infiltration of autologous substances. The authors identified 11 clinical trials, of which we included eight in the meta-analysis. RESULTS: Autologous substances achieved a good and long-lasting pain reduction, which may also be accompanied by corresponding improvement in hand function. Autologous substances appear to be more effective than corticoid infiltrations. The infiltration of autologous fat seems to be particularly promising in more advanced stages of carpometacarpal arthritis of the thumb. Our meta-analysis showed a mean pain reduction of 2.4 to 3 in visual analogue scale score and a reduction of 18 to 19 points in the Disabilities of the Arm, Shoulder, and Hand questionnaire after infiltration with autologous substances. CONCLUSION: Both platelet-rich plasma and autologous fat infiltration offer an efficient and long-lasting, minimally invasive therapy option in the treatment of carpometacarpal arthritis of the thumb.

The Impact of Antiseptic-Loaded Bacterial Nanocellulose on Different Biofilms-An Effective Treatment for Chronic Wounds?

Introduction: Pathogenic biofilms are an important factor for impaired wound healing, subsequently leading to chronic wounds. Nonsurgical treatment of chronic wound infections is limited to the use of conventional systemic antibiotics and antiseptics. Wound dressings based on bacterial nanocellulose (BNC) are considered a promising approach as an effective carrier for antiseptics. The aim of the present study was to investigate the antimicrobial activity of antiseptic-loaded BNC against in vitro biofilms. Materials and Methods: BNC was loaded with the commercially available antiseptics Prontosan® and Octenisept®. The silver-based dressing Aquacel®Ag Extra was used as a positive control. The biofilm efficacy of the loaded BNC sheets was tested against an in vitro 24-hour biofilm of Staphylococcus aureus and Candida albicans and a 48-hour biofilm of Pseudomonas aeruginosa. In vivo tests using a porcine excisional wound model was used to analyze the effect of a prolonged treatment with the antiseptics on the healing process. Results: We observed complete eradication of S. aureus biofilm in BNC loaded with Octenisept® and C. albicans biofilm for BNC loaded with Octenisept® or Prontosan®. Treatment with unloaded BNC also resulted in a statistically significant reduction in bacterial cell density of S. aureus compared to untreated biofilm. No difference on the wound healing outcome was observed for the wounds treated for seven days using BNC alone in comparison to BNC combined with Prontosan® or with Octenisept®. Conclusions: Based on these results, antiseptic-loaded BNC represents a promising and effective approach for the treatment of biofilms. Additionally, the prolonged exposure to the antiseptics does not affect the healing outcome. Prevention and treatment of chronic wound infections may be feasible with this novel approach and may even be superior to existing modalities.

Platelet-Rich Plasma in Plastic Surgery: A Systematic Review.

Introduction: Platelet-rich plasma (PRP) is gaining popularity and is applied in a variety of clinical settings. This review aims to present and evaluate available evidence regarding the use of PRP in various applications in plastic surgery. Methods: PubMed, Web of Science, Medline, and Embase were searched using predefined MeSH terms to identify studies concerning the application of PRP alone or in combination with fat grafting for plastic surgery. The search was limited to articles in English or German. Animal studies, in vitro studies, case reports, and case series were excluded. Results: Of 50 studies included in this review, eleven studies used PRP for reconstruction or wound treatment, eleven for cosmetic procedures, four for hand surgery, two for burn injuries, five for craniofacial disorders, and 17 as an adjuvant to fat grafting. Individual study characteristics were summarized. Considerable variation in preparation protocols and treatment strategies were observed. Even though several beneficial effects of PRP therapy were described, significance was not always demonstrated, and some studies yielded conflicting results. Efficacy of PRP was not universally proven in every field of application. Conclusion: This study presents an overview of current PRP treatment options and outcomes in plastic surgery. PRP may be beneficial for some indications explored in this review; however, currently available data are insufficient and systematic evaluation is limited due to high heterogeneity in PRP preparation and treatment regimens. Further randomized controlled trials employing standardized protocols are warranted.

The Use of Acellular Fish Skin Grafts in Burn Wound Management-A Systematic Review.

Background and Objectives: Burn wound healing and management continues to be a major challenge for patients and health care providers resulting in a considerable socio-economic burden. Recent advances in the development of applicable xenografts as an alternative to split-thickness skin grafts have allowed for the development of acellular fish skin. Acellular fish skin acts as a skin substitute, reducing inflammatory responses and advancing proinflammatory cytokines that promote wound healing. Due to these beneficial wound healing properties, acellular fish skin might represent an effective treatment approach in burn wound management. Materials and Methods: A systematic review of the literature, up to March 2022, was conducted using the electronic databases PubMed and Web of Science. Titles and abstracts were screened for the following key terms (variably combined): "fish skin", "fish skin grafts", "acellular fish skin", "Omega3 Wound matrix", "xenograft", "burn injury", "burns". Results: In total, 14 trials investigating the effects of acellular fish skin in burn wounds or split-thickness donor sites were determined eligible and included in the present review. Existing evidence on the use of acellular fish skin indicates an acceleration of wound healing, reduction in pain and necessary dressing changes as well as treatment-related costs and improved aesthetic and functional outcomes compared to conventional treatment options. Conclusions: Acellular fish skin xenografts may represent an effective, low-cost alternative in treatment of superficial- and partial-thickness burns. However, results mainly originate from preclinical and small cohort studies. Future larger cohort studies are warranted to elucidate the full potential of this promising approach.

Non-invasive cooling wear as an effective means of reducing subcutaneous adipose tissue mass: an in-vivo study.

OBJECTIVE: The increasing prevalence of obesity is a major health problem worldwide. Several non-surgical treatments are now available that reduce body and subcutaneous fat mass. We aimed to determine the efficacy of mild cold for body mass reduction. METHODS: Novel cooling wear, which induces mild cooling via evaporation, was worn by 29 women with overweight for 4 weeks. Specifically, the participants wore a cooling waist belt and chaps for 1 hour per day. Non-invasive lipometry was used to determine their subcutaneous adipose tissue thicknesses, and the total weight loss, abdominal circumference, and body mass index (BMI) of the participants were measured. RESULTS: The participants achieved a significant total weight loss of 0.7 kg (0.9%), and significant reductions in BMI (0.2 kg/m2) and abdominal circumference (1.9 cm, 1.7%). Furthermore, there was a trend towards a reduction in abdominal subcutaneous fat thickness and a significant reduction in thickness of the anterior thigh was noted. A questionnaire-based evaluation indicated high usability and comfort of the cooling wear. CONCLUSION: There is a high and growing demand for non-invasive treatment strategies for obesity. Cooling wear represents a novel and promising approach that may be of particular use for individuals who do not require bariatric surgery.

Quality and Vitality of Autologous Fat Grafts Harvested by Different Techniques: A Clinical Comparison Study.

BACKGROUND: Unpredictable outcomes with autologous fat grafting due to reabsorption processes present a major challenge for healthcare providers and patients. A higher number of viable adipocytes is considered to result in a higher volume being retained. Although various adverse factors have been extensively researched, other potential parameters have been less investigated or even neglected. OBJECTIVE: The aim of this study was to investigate the harvesting process of adipose tissue as the primary cause of cell damage and to determine the risk factors associated with low cell survival. METHODS: Thirty-nine male and female subjects undergoing planned elective liposuction or abdominoplasty were enrolled. Forty-seven lipoaspirates harvested by different liposuction techniques were analyzed. RNA isolation and real-time polymerase chain reaction was performed to elucidate differences in the expression of various adipocyte markers. Furthermore, scanning electron microscopy was performed on various samples to determine the cell damage caused by the different techniques. RESULTS: A statistically significant lower expression of peroxisome proliferator-activated receptor γ was detected in subjects with a higher BMI. A trend towards a lower expression of perilipin 1 in lipoaspirates harvested by a super wet + ultrasound technique, compared with dry and super wet techniques, was shown. The lowest level of cell damage determined from scanning electron microscopy images was in lipoaspirates harvested by the super wet + ultrasound technique, and this level was statistically significantly different from those obtained by the 2 other techniques. CONCLUSIONS: Optimization of the outcome in autologous fat grafting may be feasible by targeting and optimizing the harvesting process as a main risk factor for impaired adipocyte viability. Ultrasound-assisted liposuction might be considered a suitable harvesting technique.

Challenges in Burn Care during the COVID-19 Pandemic-A Scoping Review.

Objective: The aim of this review is to map and summarize the experiences of various burn centers worldwide during the COVID-19 pandemic, in order to enable future strategies with regard to the most effective measures in burn care during pandemics and to detect possible gaps in knowledge. Background: The coronavirus disease 2019 (COVID-19) pandemic had a major impact on economies, social interactions, and health systems worldwide. Burn units all over the world face a new challenge in maintaining the care of acute burn wounds and follow-up treatments while dealing with constantly changing regulations. Infrastructural changes, the establishment of efficient triage systems, protective measures, personnel resources, in addition to the maintenance of efficient patient care and the guarantee of supply chains, are challenging tasks to be addressed. This review provides an overview of recent developments regarding different strategies and methods used by burn units worldwide to safely overcome the COVID-19 pandemic outbreak. Methods: A scoping review of the literature was conducted using the electronic databases PubMed and Google Scholar. Publications were screened for the following key terms: burns, burn injuries, thermal injuries, burn center, burn unit, burn ward, in combination with COVID-19, COVID-19 pandemic, SARS-CoV-2, Corona, and Coronavirus. Articles dealing with the management of burn units during the pandemic were further analyzed and included. Results: Of the 136 publications, 10 were considered relevant to the key question and were included in the present review. Results were divided into six major topics, such as infrastructural and personnel management, triaging, severe burns and emergencies, elective surgeries, patient and visitor management, and outpatient management. Conclusion: Only a few studies about managing burn units during the COVID-19 pandemic have been published. Personnel resources and equipment needed to be redistributed to cope with country-specific challenges during the COVID-19 pandemic and to maintain adequate burn care. Since all of these articles refer to the period of the initial outbreak, a lack of clinical studies exists regarding the prevention measures taken by burn units during the COVID-19 pandemic. In addition, we identified gaps in knowledge about the impact of implemented measures on burn patient outcomes in the published literature. Further studies are mandatory in order to provide generally applicable guidelines regarding COVID-19 prevention measures at a burn unit.

In Vivo Models for Hypertrophic Scars-A Systematic Review.

Backgroundand Objectives: Hypertrophic scars following surgeries or burns present a serious concern for many patients because these scars not only lead to an aesthetical but also to a functional and psychological burden. Treatment of hypertrophic scars is challenging because despite various treatment options, a low level of evidence hinders preference of any specific treatment plan. To properly identify new therapeutic approaches, the use of in vivo models remains indispensable. A gold standard for hypertrophic scars has not been established to date. This review aims at giving a comprehensive overview of the available in vivo models. Materials and Methods: PubMed and CINAHL were queried for currently existing models. Results: Models with mice, rats, rabbits, pigs, guinea pigs and dogs are used in hypertrophic scar research. Rodent models provide the advantage of ready availability and low costs, but the number of scars per animal is limited due to their relatively small body surface, leading to a high number of test animals which should be avoided according to the 3Rs. Multiple scars per animal can be created in the guinea pig and rabbit ear model; but like other rodent models, these models exhibit low transferability to human conditions. Pig models show a good transferability, but are cost-intensive and require adequate housing facilities. Further, it is not clear if a currently available pig model can deliver clinical and histological features of human hypertrophic scars concurrently. Conclusions: None of the analyzed animal models can be clearly recommended as a standard model in hypertrophic scar research because the particular research question must be considered to elect a suitable model.