Intraluminal release of citrullinated histone 3 from various cellular origins coincides with microvascular thrombosis in burn wounds.

Loss of perfusion in the burn wound might cause wound deepening and impaired healing. We previously showed persistent microvascular thrombosis coinciding with intraluminal neutrophils extracellular traps in human burned skin. This study investigates the presence of intraluminal citrullinated histone 3 (H3cit) from different cellular origins (neutrophils, monocytes, and lymphocytes) in relation to microvascular thrombosis of burn wounds. Eschar was obtained from burn patients (n = 18) 6-40 days postburn with a mean total burned body surface area of 23%. Microvascular presence of tissue factor (TF), factor XII (FXII) and thrombi was assessed by immunohistochemistry. Intramicrovascular cell death was analyzed via immunofluorescent microscopy, combining antibodies for neutrophils (MPO), monocytes (CD14), and lymphocytes (CD45) with endothelial cell markers CD31 and H3cit. Significantly increased microvascular expression of TF, FXII, and thrombi (CD31+) was found in all eschar samples compared with control uninjured skin. Release of H3cit from different cellular origins was observed in the lumen of the dermal microvasculature in the eschar tissue 7-40 days postburn, with release from neutrophilic origin being 2.7 times more abundant. Intraluminal presence of extracellular H3cit colocalizing with either MPO, CD14, or CD45 is correlated to increased microvascular thrombosis in eschar of burn patients.

The JAK-STAT pathway in keloid pathogenesis: a systematic review with qualitative synthesis.

Keloid tissues contain inflammatory cells and upregulated pro-inflammatory cytokines. The Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway mediate cellular responses to these cytokines. We performed a systematic review on the role of the JAK-STAT pathway in keloid pathogenesis and the evidence for JAK-STAT inhibitors in keloid treatment. The search combined the terms (1) keloid and (2) JAK or TYK or STAT and included MeSH terms and synonyms. Two reviewers screened the articles and assessed the full texts on eligibility. Data were collected on the tested drugs and molecules, the type of cells and tissues used in the experiments, and study findings on the association between the JAK-STAT pathway and keloid cells and tissues. A total of twenty preclinical studies were included. Eleven preclinical studies proved that STAT3 expression and phosphorylation are enhanced in keloid tissue and keloid fibroblasts. Thirteen different JAK and/or STAT inhibitors were investigated. Tested drugs inhibited keloid progression as demonstrated by different processes, including reduced collagen production, cell proliferation and migration, increased cell cycle arrest and apoptosis, enhanced antioxidant responses, decreased (paracrine) signalling, and decreased profibrotic gene expression. No clinical studies have been published to date. Preclinical studies indicate a role for the JAK-STAT pathway in keloid pathogenesis and a potential role for JAK-STAT inhibitors in keloid treatment. The effect of these drugs should be further investigated on relevant biomarkers in a human keloid skin model, preferably including immune cells besides keloid fibroblasts and keratinocytes and in clinical studies.

Intralesional Corticosteroid Administration in the Treatment of Keloids: A Scoping Review on Injection Methods.

BACKGROUND: Intralesional corticosteroid administration (ICA) is a first-line treatment for keloids. However, its clinical results are still highly variable and often suboptimal. Treatment results may strongly be influenced by various operator-dependent factors. The aim of this study was to map the details of ICA in keloids described in randomized controlled trials (RCTs), hence presenting the scientific practice of a first-line treatment for keloids in the best available evidence. SUMMARY: A systematic search was performed on PubMed, Ovid MEDLINE, Ovid EMBASE, and CENTRAL. Eligible studies were RCTs including patients with keloids treated with intralesional corticosteroids. Treatment and study design-related data were charted on a predefined form. Thirty-eight RCTs were included for data extraction. Triamcinolone acetonide was used in 37 (97.4%) studies. Dosing per cm2 could only be compared among ten (26%) studies and varied from 1 to 20 mg. The maximum dose per session varied from 20 to 80 mg. Local anesthetics were administered in seven (20%) RCTs. Treatment intervals varied from weekly to monthly, with 4 weeks most frequently (50%) used. Needle size was reported in eleven (29%) studies and varied from 26 to 30-gauge. Syringe size was specified in four (11%) studies, being 1 mL. The injection level was described in eleven (29%) studies. Blanching as endpoint was reported in ten (26%) studies. Outcome measures varied widely, from height, surface area, or volume, to Vancouver Scar Scale, Patient and Observer Scar Assessment Scale, pain and itch scores, patient satisfaction, and different efficacy rates. Only six studies had a follow-up of ≥6 months. Recurrence was identified in two studies with 18 weeks and 1 year of follow-up. Adverse events were reported in 23 (61%) studies.

Current Practice in Keloid Treatment: a Survey of Dutch Dermatologists and Plastic Surgeons.

BACKGROUND: Several therapeutic options are available for the treatment of keloids, but it remains unclear which treatment options are most commonly used by practitioners. OBJECTIVE: To explore the prevailing treatment for different keloid phenotypes among dermatologists and plastic surgeons in the Netherlands. METHODS: Members of the Dutch society for Plastic surgery and the Dutch society for Dermatology and Venereology were asked to participate. Questions elaborated on the treatment for a small and a large keloid on the mandibula and multiple keloids on the chest. RESULTS: One hundred forty-three responses were obtained. Heterogeneity in treatment was extremely high for the small, large, and multiple keloids with 27, 35, and 33 various first choices, respectively. Intralesional corticosteroids were most often chosen for all 3 different keloid phenotypes. These were mostly (61%) administered as monotherapy for the small keloid and mostly combined with other treatments for the large keloid (19%) and multiple keloids (43%). Surgery was chosen regularly (22%) for the large keloid, mostly combined with intralesional corticosteroids (10%) or brachytherapy (8.4%). CONCLUSION: Keloid treatment is very heterogeneous among dermatologists and plastic surgeons, even in a relatively small country as the Netherlands. Moreover, the treatment choice depends on the keloid phenotype.

Short- and Long-term Outcomes of an Acellular Dermal Substitute versus Standard of Care in Burns and Reconstructions: A Phase I/II Intrapatient Randomized Controlled Trial.

OBJECTIVE: Dermal substitutes promote dermal regeneration and improve scar quality, but knowledge gaps remain regarding their efficacy and indications for use. The authors investigated the safety and short- and long-term efficacy of an acellular dermal substitute in patients with full-thickness wounds. METHODS: This intrapatient randomized controlled, open-label, phase I (safety) and phase II (efficacy) study compared treatment with Novomaix (Matricel GmbH), a dermal collagen/elastin-based scaffold, with split-thickness skin graft (STSG) only. The primary safety outcome was graft take at 5 to 7 days postsurgery. Postsurgical scar quality was assessed by measuring elasticity, color, and scores on the Patient and Observer Scar Assessment Scale at 3 months, 12 months, and 6 years. RESULTS: Twenty-five patients were included, of which 24 received treatment allocation. Graft take and wound healing were statistically significantly lower/delayed in the dermal matrix group compared with STSG alone (P < .004). Serious adverse events were delayed epithelialization in four dermal matrix and three STSG study areas. At 12 months postsurgery, skin extension (P = .034) and elasticity (P = .036) were better for the dermal matrix group compared with the group receiving STSG alone. Other scar quality parameters at 12 months and 6 years did not differ between treatment arms. CONCLUSIONS: The dermal substitute was a safe treatment modality for full-thickness wounds. Compared with STSG alone, time to wound healing was slightly increased. Nevertheless, scar quality at 12 months seemed somewhat improved in the wounds treated with the dermal substitute, indicative of enhanced scar maturation. In the long term, final scar quality was similar for both treatment modalities.

Hydrosurgical and conventional debridement of burns: randomized clinical trial.

BACKGROUND: Tangential excision of burned tissue followed by skin grafting is the cornerstone of burn surgery. Hydrosurgery has become popular for tangential excision, with the hypothesis that enhanced preservation of vital dermal tissue reduces scarring. The aim of this trial was to compare scar quality after hydrosurgical versus conventional debridement before split-skin grafting. METHODS: A double-blind randomized within-patient multicentre controlled trial was conducted in patients with burns that required split-skin grafting. One wound area was randomized to hydrosurgical debridement and the other to Weck knife debridement. The primary outcome was scar quality at 12 months, assessed with the observer part of the Patient and Observer Scar Assessment Scale (POSAS). Secondary outcomes included complications, scar quality, colour, pliability, and histological dermal preservation. RESULTS: Some 137 patients were randomized. At 12 months, scars of the hydrosurgical debrided wounds had a lower POSAS observer total item score (mean 2.42 (95 per cent c.i. 2.26 to 2.59) versus 2.54 (95 per cent c.i. 2.36 to 2.72; P = 0.023)) and overall opinion score (mean 3.08 (95 per cent c.i. 2.88 to 3.28) versus 3.30 (95 per cent c.i. 3.09-3.51); P = 0.006). Patient-reported scar quality and pliability measurements were significantly better for the hydrosurgically debrided wounds. Complication rates did not differ between both treatments. Histologically, significantly more dermis was preserved with hydrosurgery (P < 0.001). CONCLUSION: One year after surgery scar quality and pliability was better for hydrosurgically debrided burns, probably owing to enhanced histological preservation of dermis. REGISTRATION NUMBER: Trial NL6085 (NTR6232 (http://www.trialregister.nl)).

Approaches to Surgical Debridement in Necrotizing Soft Tissue Infections: Outcomes of an Animated, Interactive Survey.

BACKGROUND: Necrotizing soft tissue infections (NSTI) affect long-term quality of life in survivors. Different approaches to debridement may influence quality of life. The aim of this study was to assess the current practice of the debridement of NSTI in the Netherlands. METHODS: An animated, interactive online survey was distributed among general surgeons and plastic surgeons in the Netherlands. Two NSTI-cases were presented, followed by questions regarding the preferred surgical approach. Case one described a woman with a swollen, red leg, with signs of sepsis and without visible necrosis. Case two described an immunocompromised man with septic shock syndrome and extensive necrosis. RESULTS: In total 232 responses were included (143 general surgeons, 89 plastic surgeons). In case one, 32% chose to preserve all skin, while 17% chose to resect all skin above the affected fascia, including normal-looking skin. In case two, all participants resected necrotic skin, and most (88%) also blue discolored skin. While 32% did not resect more than blue discolored and necrotic skin, 35% also resected red-colored skin, and 21% all skin overlying the affected fascia, including normal colored skin. Respondents working in a hospital with a burn center tended to preserve more skin, whereas plastic surgeons chose more often for skin resection compared to general surgeons. CONCLUSIONS: By using a novel approach to a survey, the authors demonstrate the existence of extensive practice variety regarding the approach to debridement of NSTI among Dutch general and plastic surgeons. Consensus is needed, followed by targeted education of surgeons.

Scar quality in children with burns 5-7 years after injury: A cross-sectional multicentre study.

Long-term scar formation is an important adverse consequence in children with burns, however, information regarding scar quality in the long-term is lacking. Therefore, we evaluated scar quality and its predictors in children with burns 5-7 years after injury. Parents of children with mild/intermediate burns (≤10% total body surface area burned), and of children with severe burns (>10% burned) completed the patient scale of the Patient and Observer Scar Assessment Scale (POSAS 2.0) for their children's-in their opinion-worst scar 5-7 years post-burn. Outcomes and predictive factors of scar quality were studied, and, for children with severe burns, POSAS parent scores were compared with observer scores. We included 103 children with mild/intermediate burns and 28 with severe burns (response rate: 51%). Most children (87%) had scars that differed from normal skin, with most differences reported for colour, and least for pain. Except for colour, children with severe burns had significantly higher scores (difference 0-2 points) on all scar characteristics (representing poorer scar quality) compared with children with mild/intermediate burns. Parent POSAS scores were on average 2.0-2.6 points higher compared to observer scores. Number of surgeries predicted both the mean POSAS and the mean overall opinion of a scar. In conclusion, 5-7 years post-burn, the scar of the majority of children differed from normal skin, especially on the characteristic colour. The uncovered insights are useful in counselling of children and their parents on expectations of the final outcome of their (children's) scar(s), and help in further targeting scar prevention strategies for the individual child.

Effective enzymatic debridement of burn wounds depends on the denaturation status of collagen.

The treatment of burn wounds by enzymatic debridement using bromelain has shown promising results in our burn center. However, inadequate debridement occurred in a few cases in which the etiology of the burn was attributed to relatively low temperature burns. We hypothesized that bromelain is ineffective in burns in which collagen denaturation, which occurs approximately at 65°C, has not taken place. Our objective was to assess whether there is a relationship between the denaturation of collagen and the ability of bromelain to debride acute scald burn wounds of different temperatures. Ex vivo human skin from four different donors was cut into 1x1 cm samples, and scald burns were produced by immersion in water at temperatures of 40°C, 50°C, 60°C, 70°C, and 100°C for 20 minutes. Denaturation of collagen was assessed with histology, using hematoxylin and eosin (H&E) staining and a fluorescently labeled collagen hybridizing peptide (CHP), and with second harmonic generation (SHG) microscopy. Burned samples and one control sample (room temperature) were weighed before and after application of enzymatic debridement to assess the efficacy of enzymatic debridement. After enzymatic debridement, a weight reduction of 80% was seen in the samples heated to 70°C and 100°C, whereas the other samples showed a reduction of 20%. Unfolding of collagen, loss of basket-weave arrangement, and necrosis was seen in samples heated to 60°C or higher. Evident CHP fluorescence, indicative of collagen denaturation, was seen in samples of 60°C, 70°C and 100°C. SHG intensity, signifying intact collagen, was significantly lower in the 70°C and 100°C group (P <.05) compared to the lower temperatures. In conclusion, denaturation of collagen in skin samples occurred between 60°C and 70°C and strongly correlated with the efficacy of enzymatic debridement. Therefore, enzymatic debridement with the use of bromelain is ineffective in scald burns lower than 60°C.

Validity of thermography for measuring burn wound healing potential.

Accurate assessment of burn wound depth and the associated healing potential is vital in determining the need for surgical treatment in burns. Infrared thermography measures the temperature of the burn wound noninvasively, thereby providing indirect information on its blood flow. Previous research demonstrated that a small, low-priced, handheld thermal imager has an excellent reliability, but a moderate validity for measuring burn wound healing potential. A new and more sensitive version of this convenient device has become available. The aim of this study was to evaluate the validity of thermography for measuring burn wound healing potential, compared to Laser Doppler Imaging (LDI) as a reference standard. Thermal images and LDI scans were obtained from burn wounds between 2 and 5 days postburn. Temperature differences between burned and nonburned skin (ΔT) were calculated. To evaluate validity, ΔT values were compared to the healing potential categories assessed by LDI. Two receiver operating characteristic curves were created and two ΔT cutoff values were calculated to illustrate the ability to discriminate between burn wounds that heal in a time period of less than 14 days, between 14 and 21 days, and more than 21 days. Between June and October 2018, 43 burn wounds in 32 patients were measured. ΔT cutoff values of 0.6°C (sensitivity 68%, specificity 95%) and -2.3°C (sensitivity 30%, specificity 95%) were calculated to discriminate between burn wounds that heal in <14 and ≥14 days, and burn wound that heal in ≤21 and >21 days, respectively. This study shows a good validity of the feasible thermal imager for the assessment of burn wound healing potential. Therefore, we consider it a promising technique to be used for triage in local hospitals and general practices, and as a valuable addition to clinical evaluation in burn centers.

Sustainable effectiveness of single-treatment autologous fat grafting in adherent scars.

Following severe injury, not just the skin but also the subcutis may be destroyed. Consequently, the developing scar can become adherent to underlying structures. Reconstruction of the subcutis can be achieved by autologous fat grafting. Our aim was to evaluate the long-term scar outcome after single-treatment autologous fat grafting using a comprehensive scar evaluation protocol. Scar assessment was performed preoperatively in 40 patients. A 12-month follow-up assessment was performed in 36 patients, using the Cutometer, the Patient and Observer Scar Assessment Scale, and DSM II ColorMeter. The Cutometer parameters elasticity and maximal extension improved with 28 and 22% (both p < 0.001), respectively. Nearly all scores of the scar assessment scale decreased significantly, which corresponds to improved scar quality. In addition, the mean melanin score was ameliorated over time. Thus, we demonstrated the sustainable effectiveness of single-treatment autologous fat grafting in adherent scars, indicated by improved pliability, and overall scar quality.

Neutrophil extracellular traps coincide with a pro-coagulant status of microcirculatory endothelium in burn wounds.

Burn-induced tissue loss is partly related to secondary expansion of necrosis into vital dermis neighboring the initial burn injury. An important factor herein is the severe loss of perfusion of the burn wound, probably caused by microvascular damage induced by the intense local inflammatory responses as well as burn-induced hypercoagulation. We hypothesize that the formation of neutrophilic extracellular traps (NETs) play an important role in this. The purpose of this study was to investigate postburn intravascular thrombosis, NETs formation and the coagulant state in the microvasculature of burns in both animal models and patients. We used two in vivo burn wound models: rats and pigs. In rats, the entire wound was excised at day 14 postburn and in pigs burn wound biopsies were collected at different time points up to 60 days postburn. To confirm the data in patients, eschar from the burn wound was obtained from burn wound patients at different time points after wounding. The number of intravascular thrombi, the presence of intravascular NETs and the number of tissue factor (TF) positive blood vessels in the burn wound was determined. In rats, a significant increase in intravascular thrombi and TF expression was observed 14 days postburn, that in majority coincided with NETs. In pigs, a significant increase in intravascular thrombi and TF expression was found over time up to 60 days postburn, that in majority coincided with NETs too. Also in eschar of burn wound patients, a significant increase in intravascular thrombi was noted, that in majority coincided with NETs, already 0.5 days postburn and remained elevated up to 46 days postburn. This study shows the presence of NETosis in microcirculatory thrombosis of burn wounds and a switch in the microcirculatory endothelium toward a procoagulant phenotype.

A mathematical model for the simulation of the contraction of burns.

A continuum hypothesis-based model is developed for the simulation of the contraction of burns in order to gain new insights into which elements of the healing response might have a substantial influence on this process. Tissue is modeled as a neo-Hookean solid. Furthermore, (myo)fibroblasts, collagen molecules, and a generic signaling molecule are selected as model components. An overview of the custom-made numerical algorithm is presented. Subsequently, good agreement is demonstrated with respect to variability in the evolution of the surface area of burns over time between the outcomes of computer simulations and measurements obtained in an experimental study. In the model this variability is caused by varying the values for some of its parameters simultaneously. A factorial design combined with a regression analysis are used to quantify the individual contributions of these parameter value variations to the dispersion in the surface area of healing burns. The analysis shows that almost all variability in the surface area can be explained by variability in the value for the myofibroblast apoptosis rate and, to a lesser extent, the value for the collagen molecule secretion rate. This suggests that most of the variability in the evolution of the surface area of burns over time in the experimental study might be attributed to variability in these two rates. Finally, a probabilistic analysis is used in order to investigate in more detail the effect of variability in the values for the two rates on the healing process. Results of this analysis are presented and discussed.

Differential item functioning in the Observer Scale of the POSAS for different scar types.

PURPOSE: To investigate whether the Observer Scale of the Patient and Observer Scar Assessment Scale (POSAS) can serve as a generic measure for scar quality across different scar types. METHODS: A collection of POSAS scores derived from several clinical trials on burn (n = 404), linear (n = 384), and keloidal scars (n = 282) was analyzed using the partial credit model of the Rasch analysis package RUMM2030. RESULTS: Differential item functioning (DIF) was observed for the Observer Scale of the POSAS between the three scar types for the items pliability, thickness, and surface area, which could be solved by item splitting. The items pigmentation and thickness showed disordered thresholds, considerable misfit, and unpredictability. CONCLUSION: Users of the Observer Scale of the POSAS must be aware that the raw scores obtained from burn, linear, and keloidal scars cannot be compared without the scar-specific DIF adjustment of the items pliability, thickness, and surface area.

Thermal Imaging for Burn Wound Depth Assessment: A Mixed-Methods Implementation Study.

Background: Implementing innovations emerging from clinical research can be challenging. Thermal imagers provide an accessible diagnostic tool to increase the accuracy of burn wound depth assessment. This mixed-methods implementation study aimed to assess the barriers and facilitators, design implementation strategies, and guide the implementation process of thermal imaging in the outpatient clinic of a burn centre. Methods: This study was conducted between September 2022 and February 2023 in Beverwijk, The Netherlands. Semi-structured interviews with burn physicians guided by the Consolidated Framework for Implementation Research (CFIR) were conducted to identify barriers and facilitators. Based on the barriers, implementation strategies were developed with the CFIR-ERIC Matching Tool, and disseminated to support the uptake of the thermal imager. Subsequently, thermal imaging was implemented in daily practice, and an iterative RE-AIM approach was used to evaluate the implementation process. Results: Common facilitators for the implementation of the thermal imager were the low complexity, the relative advantage above other diagnostic tools, and benefits for patients. Common barriers were physicians' attitude towards and perceived value of the intervention, the low compatibility with the current workflow, and a lack of knowledge about existing evidence. Six implementation strategies were developed: creating a formal implementation blueprint, promoting adaptability, developing educational materials, facilitation, conducting ongoing training, and identifying early adopters. These strategies resulted in the effective implementation of the thermal imager, reflected by a >70% reach among eligible patients, and >80% effectiveness and adoption. Throughout the implementation process, compatibility, and available resources remained barriers, resulting in low ratings on RE-AIM dimensions. Conclusions: This study developed implementation strategies based on the identified CFIR constructs that impacted the implementation of a thermal imager for burn wound assessment in our outpatient clinic. The experiences and findings of this study could be leveraged to guide the implementation of thermal imaging and other innovations in burn care.

IDENTIFICATION OF POTENTIALLY MODIFIABLE FACTORS TO IMPROVE RECOGNITION AND OUTCOME OF NECROTIZING SOFT-TISSUE INFECTIONS.

ABSTRACT: Background : Necrotizing soft-tissue infections (NSTIs) present a surgical emergency of increasing incidence, which is often misdiagnosed and associated with substantial mortality and morbidity. A retrospective multicenter (11 hospitals) cohort study was initiated to identify the early predictors of misdiagnosis, mortality, and morbidity (skin defect size and amputation). Methods : Patients of all ages who presented with symptoms and were admitted for acute treatment of NSTIs between January 2013 and December 2017 were included. Generalized estimating equation analysis was used to identify early predictors (available before or during the first debridement surgery), with a significance level of P < 0.05. Results : The median age of the cohort (N = 216) was 59.5 (interquartile range = 23.6) years, of which 138 patients (63.9%) were male. Necrotizing soft-tissue infections most frequently originated in the legs (31.0%) and anogenital area (30.5%). More than half of the patients (n = 114, 54.3%) were initially misdiagnosed. Thirty-day mortality was 22.9%. Amputation of an extremity was performed in 26 patients (12.5%). Misdiagnosis was more likely in patients with a higher Charlson Comorbidity Index (ß = 0.20, P = 0.001), and less likely when symptoms started in the anogenital area (ß = -1.20, P = 0.003). Besides the established risk factors for mortality (septic shock and age), misdiagnosis was identified as an independent predictor of 30-day mortality (ß = 1.03, P = 0.01). The strongest predictors of the final skin defect size were septic shock (ß = 2.88, P < 0.001) and a skin-sparing approach to debridement (ß = -1.79, P = 0.002). Conclusion : Recognition of the disease is essential for the survival of patients affected by NSTI, as is adequate treatment of septic shock. The application of a skin-sparing approach to surgical debridement may decrease morbidity.

The efficacy of therapeutic interventions on paediatric burn patients' height, weight, body composition, and muscle strength: A systematic review and meta-analysis.

OBJECTIVE: To evaluate the efficacy of therapeutic interventions on pediatric burn patients' height, weight, body composition, and muscle strength. METHODS: A systematic literature search was conducted in PubMed, Embase, and Web of Science up to March 2021. Eligible interventional studies reported metrics on the height, weight, body composition, or muscle strength of pediatric burn patients in a peer-reviewed journal. Meta-analyses were performed if ≥ 2 trials of clinical homogeneity reported on an outcome measure at the same time point post-burn. RESULTS: Twenty-six interventional studies were identified, including twenty-two randomised controlled trials and four non-randomised trials. Most studies were conducted by a single institution. On average, the burn covered 45.3% ( ± 9.9) of the total body surface area. Three categories of interventions could be distinguished: rehabilitative exercise programs, pharmacologic agents, and nutrition support. CONCLUSIONS: Each of the interventions had a positive effect on height, weight, body composition, or muscle strength. The decision to initiate an intervention should be made on a case-by-case basis following careful consideration of the benefits and risks. In future research, it is important to evaluate the heterogeneity of intervention effects and whether participation in an intervention allowed pediatric burn patients to reach the physical and functional status of healthy peers.

The minimal important change (MIC) and minimal clinically important difference (MCID) of the patient and observer scar assessment scale (POSAS) 2.0.

BACKGROUND: The Patient and Observer Scar Assessment Scale (POSAS) is frequently used to assess scar quality after burns. It is important to be aware of the minimal important change (MIC) and the minimal clinically important difference (MCID) to establish if a POSAS score represents a clinically relevant change or difference. The aim of this study is to explore the MIC and MCID of POSAS version 2.0. METHODS: This prospective study included 127 patients with deep dermal burns that underwent split thickness skin grafting with a mean age of 44 years (range 0 - 87) and total body surface area burned of 10 % (range 0.5 - 55). POSAS data was obtained for one burn scar area at three, six, and 12 months after split skin grafting. At the second and third visits, patients rated the degree of clinical change in scar quality in comparison to the previous visit. At 12 months, they completed the POSAS for a second burn scar area and rated the degree of clinical difference between the two scar areas. Two anchor-based methods were used to determine the MIC and MCID. RESULTS: MIC values of the patient POSAS ranged from - 0.59 to - 0.29 between three and six months and from - 0.75 to - 0.38 between six and 12 months follow-up. Both had a poor discriminatory value. MCID values ranged from - 0.39 and - 0.08, with a better discriminatory value. CONCLUSION: Results suggest that patients consider minor differences (less than 0.75 on the 1-10 scale) in POSAS scores as clinically important scar quality changes. MCID values can be used to evaluate the effects of burn treatment and perform sample-size calculations.

Improving patient care by virtual case discussion between plastic surgeons and residents of Uganda and the Netherlands.

INTRODUCTION: Traditional on-site missions of plastic surgeons from "high-income countries" in "low- and middle-income countries" are often limited in time and lack proper follow-up. Regular digital collaboration could lead to a more impactful and durable exchange of knowledge for plastic surgeons and residents in both settings. AIMS: The aim of this study was to evaluate the satisfaction of the first twelve months of weekly digital meetings, explore advantages/disadvantages, and to provide tools for similar initiatives. METHODS: Weekly meetings started from August 2021. An encrypted digital connection allowed residents and plastic surgeons from Uganda and the Netherlands to discuss cases for educational purposes, where treatment options were considered. After twelve months, a survey was sent to participants from both countries to indicate the meetings' strengths, weaknesses, and possible improvements. RESULTS: A total of 18 participants responded to the questionnaire (ten plastic surgeons, six residents, and two researchers). The strengths of the meetings were the accessibility of the meetings, knowledge exchange and practice for residents' final exams. Possible improvements included having a clear format for patient discussion, a session moderator and better internet connectivity. Moreover, a database to assess the impact of the given intervention on the patient cases by evaluating postoperatively (e.g. three months), could further improve clinical care. CONCLUSIONS: Virtual patient discussions subjectively contributed to medical education at both locations. Improved digital infrastructure and a collaborative database could further maximize learning capacity. Furthermore, digital proctoring is a promising way to establish sustainable collaborations between high- and low-resource countries.