Barriers and co-designed strategies for the implementation of negative pressure wound therapy in acute pediatric burn care in Australia: A mixed method study.

PURPOSE: Pediatric burn injuries are a global clinical issue causing significant morbidity. Early adjunctive negative pressure wound therapy improves re-epithelialization rates in children with burns, yet adoption in acute burn care is inconsistent. This investigation aimed to determine barriers to the implementation of adjunctive negative pressure wound therapy for the acute management of pediatric burns and co-design targeted implementation strategies. METHODS: A sequential mixed methods design was used explore barriers to adjunctive negative pressure wound therapy implementation in acute pediatric burn care. An online questionnaire was disseminated to healthcare professionals within four major Australian pediatric hospitals, each with a dedicated burns service. Barriers were coded according to the Consolidated Framework for Implementation Research (CFIR). Semi-structured interviews with senior clinicians tailored implementation strategies to local contexts. A stakeholder consensus meeting consolidated implementation strategies and local processes. RESULTS: Sixty-three healthcare professionals participated in the questionnaire, and semi-structured interviews involved nine senior burn clinicians. We identified eight implementation barriers across all five CFIR domains then co-designed targeted strategies to address identified barriers. Barriers included lack of available resources, limited access to knowledge and information, individual stage of change, patient needs and resources, limited knowledge and beliefs about the intervention, lack of external policies, intervention complexity, and poor implementation planning. CONCLUSION: Multiple contextual factors affect negative pressure wound therapy uptake in acute pediatric burn settings. Results will inform a multi-state stepped-wedge cluster randomized controlled trial. Additional resources, education, training, updated policies, and guidelines are required for successful implementation. It is anticipated that adjunctive negative pressure wound therapy, in conjunction with tailored implementation strategies, will enhance adoption and sustainability. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry: ACTRN12622000166774. Registered 1 February 2022.

MicroRNAs involved in human skin burns, wound healing and scarring.

MicroRNAs are small, non-coding RNAs that regulate gene expression, and consequently protein synthesis. Downregulation and upregulation of miRNAs and their corresponding genes can alter cell apoptosis, proliferation, migration and fibroproliferative responses following a thermal injury. This review summarises the evidence for altered human miRNA expression post-burn, and during wound healing and scarring. In addition, the most relevant miRNA targets and their roles in potential pathways are described. Previous studies using molecular techniques have identified 197 miRNAs associated with human wound healing, burn wound healing and scarring. Five miRNAs alter the expression of fibroproliferative markers, proliferation and migration of fibroblasts and keratinocytes post-burn: hsa-miR-21 and hsa-miR-31 are increased after wounding, and hsa-miR-23b, hsa-miR-200b and hsa-let-7c are decreased. Four of these five miRNAs are associated with the TGF-ß pathway. In the future, large scale, in vivo, longitudinal human studies utilising a range of cell types, ethnicity and clinical healing outcomes are fundamental to identify burn wound healing and scarring specific markers. A comprehensive understanding of the underlying pathways will facilitate the development of clinical diagnostic or prognostic tools for better scar management and the identification of novel treatment targets for improved healing outcomes in burn patients.

Local burn wound environment versus systemic response: Comparison of proteins and metabolites.

In this study, paired blood plasma (BP) and blister fluid (BF) samples from five paediatric burn patients were analysed using mass spectrometry to compare their protein and metabolite composition. The relative quantification of proteins was achieved through a label-free data independent acquisition mode. The relative quantification of metabolites was achieved using a Shimadzu Smart Metabolite Database gas chromatography mass spectrometry (GCMS) targeted assay. In total, 562 proteins and 141 individual metabolites were identified in the samples. There was 81% similarity in the proteins present in the BP and BF, with 50 and 54 unique proteins found in each sample type respectively. BF contained keratinocyte proliferation-related proteins and blood plasma contained abundant blood clotting proteins and apolipoproteins. BF contained more carbohydrates and less alpha-hydroxy acid metabolites than the BP. In this study, there were unique proteins and metabolites in BF and BP which were reflective of the local wound environment and systemic environments respectively. The results from this study demonstrate that the biomolecule content of BF is mostly the same as blood, but it also contains information specific to the local wound environment.

The modulation of the burn wound environment by negative pressure wound therapy: Insights from the proteome.

Negative pressure wound therapy has been used to promote wound healing in a variety of settings, including as an adjunct to silver-impregnated dressings in the acute management of paediatric burns. Fluid aspirated by the negative pressure wound therapy system represents a potentially insightful research matrix for understanding the burn wound microenvironment and the intervention's biochemical mechanisms of action. The aim of this study was to characterize the proteome of wound fluid collected using negative pressure wound therapy from children with small-area thermal burns. Samples were obtained as part of a randomized controlled trial investigating the clinical efficacy of adjunctive negative pressure wound therapy. They were compared with blister fluid specimens from paediatric burn patients matched according to demographic and injury characteristics. Protein identification and quantification were performed via liquid chromatography tandem mass spectrometry and sequential window acquisition of all theoretical mass spectra data-independent acquisition. Proteins and biological pathways that were unique to or enriched in negative pressure wound therapy fluid samples were evaluated using principal components, partial least squares-discriminant, and gene ontology enrichment analyses. Eight viable samples of negative pressure wound therapy fluid were collected and analyzed with eight matched blister fluid samples. A total of 502 proteins were quantitatively profiled in the negative pressure wound therapy fluid, of which 444 (88.4%) were shared with blister fluid. Several proteins exhibited significant abundance differences between fluid types, with negative pressure wound therapy fluid showing a higher abundance of matrix metalloproteinase-9, arginase-1, low affinity immunoglobulin gamma Fc region receptor III-A, filamin-A, alpha-2-macroglobulin, and hemoglobin subunit alpha. The results lend support to the hypothesis that negative pressure wound therapy augments wound healing through the modulation of factors involved in the inflammatory response, granulation tissue synthesis, and extracellular matrix maintenance. Data are available via ProteomeXchange with identifier PXD023168.

Menstrual fluid factors facilitate tissue repair: identification and functional action in endometrial and skin repair.

Repair after damage is essential for tissue homeostasis. Postmenstrual endometrial repair is a cyclical manifestation of rapid, scar-free, tissue repair taking ∼3-5 d. Skin repair after wounding is slower (∼2 wk). In the case of chronic wounds, it takes months to years to restore integrity. Herein, the unique "rapid-repair" endometrial environment is translated to the "slower repair" skin environment. Menstrual fluid (MF), the milieu of postmenstrual endometrial repair, facilitates healing of endometrial and keratinocyte "wounds" in vitro, promoting cellular adhesion and migration, stimulates keratinocyte migration in an ex vivo human skin reconstruct model, and promotes re-epithelialization in an in vivo porcine wound model. Proteomic analysis of MF identified a large number of proteins: migration inhibitory factor, neutrophil gelatinase-associated lipocalin, follistatin like-1, chemokine ligand-20, and secretory leukocyte protease inhibitor were selected for further investigation. Functionally, they promote repair of endometrial and keratinocyte wounds by promoting migration. Translation of these and other MF factors into a migration-inducing treatment paradigm could provide novel treatments for tissue repair.-Evans, J., Infusini, G., McGovern, J., Cuttle, L., Webb, A., Nebl, T., Milla, L., Kimble, R., Kempf, M., Andrews, C. J., Leavesley, D., Salamonsen, L. A. Menstrual fluid factors facilitate tissue repair: identification and functional action in endometrial and skin repair.

Characterization of the Blister Fluid Proteome for Pediatric Burn Classification.

Blister fluid (BF) is a novel and viable research matrix for burn injury study, which can reflect both systemic and local microenvironmental responses. The protein abundance in BF from different burn severities were initially observed using a 2D SDS-PAGE approach. Subsequently, a quantitative data independent acquisition (DIA) method, SWATH, was employed to characterize the proteome of pediatric burn blister fluid. More than 600 proteins were quantitatively profiled in 87 BF samples from different pediatric burn patients. These data were correlated with clinically assessed burn depth and time until complete wound re-epithelialization through several different statistical analyses. Several proteins from these analyses exhibited significant abundance change between different burn depth or re-epithelialization groups, and can be considered as potential biomarker candidates. Further gene ontology (GO) enrichment analysis of the significant proteins revealed the most significant burn related biological processes (BP) that are altered with burn depth, including homeostasis and oxygen transport. However, for wounds with re-epithelialization times more or less than 21 days, the significant GO annotations were related to enzyme activity. This quantitative proteomics investigation of burn BF may enable objective classification of burn wound severity and assist with clinical decision-making. Data are available via ProteomeXchange with identifier PXD011102.

Evidence-based injury prediction data for the water temperature and duration of exposure for clinically relevant deep dermal scald injuries.

Deep dermal burn injuries require extensive medical care; however, the water temperatures and durations of exposure that result in a severe scald injury are unknown. This study used a porcine burn model to investigate the time and temperature threshold for clinically relevant deep dermal injuries for both immersion (long duration) and spill/splash (short duration) scald events. Scald wounds were created on the flanks of anaesthetized juvenile large White pigs (27 kg). Acute tissue injury evaluations performed at 1 hour and days 1, 3, and 7 postburn (16 pigs) included: wound examination, biopsies, and laser Doppler imaging. Up to 20 burn combinations were tested including: 50-60 °C water for 1-10 minutes (immersion); and 60-90 °C water for 5 seconds (spill/splash). Burn conditions demonstrating mid-to-deep dermal damage histologically were followed for 21 days to assess time to reepithelialize (eight pigs). Histologically, depth of damage increased until day 3 postburn. Damage to ≥75% of the depth of dermis was associated with burns taking longer than 3 weeks to fully reepithelialize. For spill/splash (5 seconds) scalds, water at ≥75 °C showed damage to mid-dermis or deeper by day 3; however, only burns from water ≥85 °C were not reepithelialized by day 21. For immersion scalds of equivalent duration, water at 55 °C caused significantly deeper dermal damage than 50 °C (p < 0.05) at day 3. Immersion scalds that were not fully reepithelialized by day 21 included 50 °C for >10 minutes, 55 °C for 5 minutes, 60 °C for 60 seconds, and 70 °C for > 15 seconds. This research provides valuable evidence-based injury prediction data, which can be used to inform future burn injury prevention guidelines/legislation to reduce the risk of severe scald injuries and support medicolegal opinions for cases where an inflicted mechanism of injury is alleged.

Comparing the reported burn conditions for different severity burns in porcine models: a systematic review.

There are many porcine burn models that create burns using different materials (e.g. metal, water) and different burn conditions (e.g. temperature and duration of exposure). This review aims to determine whether a pooled analysis of these studies can provide insight into the burn materials and conditions required to create burns of a specific severity. A systematic review of 42 porcine burn studies describing the depth of burn injury with histological evaluation is presented. Inclusion criteria included thermal burns, burns created with a novel method or material, histological evaluation within 7 days post-burn and method for depth of injury assessment specified. Conditions causing deep dermal scald burns compared to contact burns of equivalent severity were disparate, with lower temperatures and shorter durations reported for scald burns (83°C for 14 seconds) compared to contact burns (111°C for 23 seconds). A valuable archive of the different mechanisms and materials used for porcine burn models is presented to aid design and optimisation of future models. Significantly, this review demonstrates the effect of the mechanism of injury on burn severity and that caution is recommended when burn conditions established by porcine contact burn models are used by regulators to guide scald burn prevention strategies.

The biochemistry of blister fluid from pediatric burn injuries: proteomics and metabolomics aspects.

Burn injury is a prevalent and traumatic event for pediatric patients. At present, the diagnosis of burn injury severity is subjective and lacks a clinically relevant quantitative measure. This is due in part to a lack of knowledge surrounding the biochemistry of burn injuries and that of blister fluid. A more complete understanding of the blister fluid biochemistry may open new avenues for diagnostic and prognostic development. Burn insult induces a highly complex network of signaling processes and numerous changes within various biochemical systems, which can ultimately be examined using proteome and metabolome measurements. This review reports on the current understanding of burn wound biochemistry and outlines a technical approach for 'omics' profiling of blister fluid from burn wounds of differing severity.

Cost-Effectiveness of a Nonpharmacological Intervention in Pediatric Burn Care.

OBJECTIVE: To report the cost-effectiveness of a tailored handheld computerized procedural preparation and distraction intervention (Ditto) used during pediatric burn wound care in comparison to standard practice. METHODS: An economic evaluation was performed alongside a randomized controlled trial of 75 children aged 4 to 13 years who presented with a burn to the Royal Children's Hospital, Brisbane, Australia. Participants were randomized to either the Ditto intervention (n = 35) or standard practice (n = 40) to measure the effect of the intervention on days taken for burns to re-epithelialize. Direct medical, direct nonmedical, and indirect cost data during burn re-epithelialization were extracted from the randomized controlled trial data and combined with scar management cost data obtained retrospectively from medical charts. Nonparametric bootstrapping was used to estimate statistical uncertainty in cost and effect differences and cost-effectiveness ratios. RESULTS: On average, the Ditto intervention reduced the time to re-epithelialize by 3 days at AU$194 less cost for each patient compared with standard practice. The incremental cost-effectiveness plane showed that 78% of the simulated results were within the more effective and less costly quadrant and 22% were in the more effective and more costly quadrant, suggesting a 78% probability that the Ditto intervention dominates standard practice (i.e., cost-saving). At a willingness-to-pay threshold of AU$120, there is a 95% probability that the Ditto intervention is cost-effective (or cost-saving) against standard care. CONCLUSIONS: This economic evaluation showed the Ditto intervention to be highly cost-effective against standard practice at a minimal cost for the significant benefits gained, supporting the implementation of the Ditto intervention during burn wound care.

Unremitting pro-inflammatory T-cell phenotypes, and macrophage activity, following paediatric burn injury.

Objectives: The aim of this study was to characterise the dynamic immune profile of paediatric burn patients for up to 18 months post-burn. Methods: Flow cytometry was used to measure 25 cell markers, chemokines and cytokines which reflected both pro-inflammatory and anti-inflammatory immune profiles. Peripheral blood mononuclear cells from 6 paediatric burn patients who had returned for repeated burn and scar treatments for > 4 timepoints within 12 months post-burn were compared to four age-matched healthy controls. Results: While overall proportions of T cells, NK cells and macrophages remained relatively constant, over time percentages of these immune cells differentiated into effector and proinflammatory cell phenotypes including Th17 and activated γδ T cells. Circulating proportions of γδ T cells increased their expression of pro-inflammatory mediators throughout the burn recovery, with a 3-6 fold increase of IL-17 at 1-3 weeks, and NFκß 9-18 months post-burn. T-regulatory cell plasticity was also observed, and Treg phenotype proportions changed from systemically reduced skin-homing T-regs (CCR4+) and increased inflammatory (CCR6+) at 1-month post-burn, to double-positive cell types (CCR4+CCR6+) elevated in circulation for 18 months post-burn. Furthermore, Tregs were observed to proportionally express less IL-10 but increased TNF-α over 18 months. Conclusion: Overall, these results indicate the circulating percentages of immune cells do not increase or decrease over time post-burn, instead they become highly specialised, inflammatory and skin-homing. In this patient population, these changes persisted for at least 18 months post-burn, this 'immune distraction' may limit the ability of immune cells to prioritise other threats post-burn, such as respiratory infections.

Inflammatory proteins and neutrophil extracellular traps increase in burn blister fluid 24h after burn.

Burn wound blister fluid is a valuable matrix for understanding the biological pathways associated with burn injury. In this study, 152 blister fluid samples collected from paediatric burn wounds at three different hospitals were analysed using mass spectrometry proteomic techniques. The protein abundance profile at different days after burn indicated more proteins were associated with cellular damage/repair in the first 24 h, whereas after this point more proteins were associated with antimicrobial defence. The inflammatory proteins persisted at a high level in the blister fluid for more than 7 days. This may indicate that removal of burn blisters prior to two days after burn is optimal to prevent excessive or prolonged inflammation in the wound environment. Additionally, many proteins associated with the neutrophil extracellular trap (NET) pathway were increased after burn, further implicating NETs in the post-burn inflammatory response. NET inhibitors may therefore be a potential treatment to reduce post-burn inflammation and coagulation pathology and enhance burn wound healing outcomes.

Effect of Rho-Associated Protein Kinase Inhibitors on Epidermal Keratinocytes: A Proposed Application for Burn Wound Healing.

Rho-associated protein kinases (ROCKs) affect a variety of cellular functions, including cell attachment, migration, and proliferation. ROCK inhibitors therefore have potential as tools for optimizing cell behavior in tissue engineering applications, including the manufacturing of cultivated epithelial autografts (CEAs) used in the treatment of burn patients. For example, ROCK inhibitors may facilitate earlier engraftment of CEA sheets by increasing the proliferation of skin keratinocytes ex vivo. Nevertheless, the current understanding of ROCK inhibitor action on epidermal keratinocytes is unclear owing to multiple drug formulations, drug concentrations, and cellular function assays having been used. The aim of this review article therefore is to identify consistent patterns of ROCK inhibitor action on human keratinocytes, as well as revealing key knowledge gaps. In doing so, we propose a clearer course of action for pursuing the potential benefits of ROCK inhibitors for the future treatment of burn patients. Impact statement The properties of Rho-associated protein kinase (ROCK) inhibitors are already used clinically within the fields of cardiology, neurology, and ophthalmology. These results encourage the broadening of ROCK inhibitor uses for other clinical applications. With respect to burn patients, ROCK inhibitors may facilitate improvements in patient survival and healing by reducing the time required for generating cultivated epithelial autograft (CEA) sheets from patient biopsies. Nevertheless, varying approaches to studying the effects of ROCK inhibitors on skin cells in vitro have complicated the development of improved protocols. Our review aims to clarify a diverse and growing body of literature as to the potential benefits for burn patients.

Management of non-severe burn wounds in children and adolescents: optimising outcomes through all stages of the patient journey.

Paediatric burn injuries are common, especially in children younger than 5 years, and can lead to poor physical and psychosocial outcomes in the long term. In this Review, we aim to summarise the key factors and interventions before hospital admission and following discharge that can improve the long-term outcomes of paediatric burns. Care can be optimised through first aid treatment, correct initial assessment of burn severity, and appropriate patient referral to a burns centre. Scar prevention or treatment and patient follow-up after discharge are also essential. As most burn injuries in children are comparatively small and readily survivable, this Review does not cover the perioperative management associated with severe burns that require fluid resuscitation, or inhalational injury. Burns disproportionately affect children from low socioeconomic backgrounds and those living in low-income and middle-income countries, with ample evidence to suggest that there remains scope for low-cost interventions to improve care for those patients with the greatest burden of burn injury. Current knowledge gaps and future research directions are discussed.

An Exploratory Study Demonstrating That Salivary Cytokine Profiles Are Altered in Children With Small Area Thermal Injury.

Serum can be used to investigate changes in cytokine concentration following burn injury in children; however, for children receiving treatment in an outpatient setting, blood is not routinely collected and therefore cannot be used for monitoring. The aim of this study was to investigate the use of saliva as a noninvasive tool for predicting burn outcomes by measuring the concentration of salivary cytokines in children with small area burns. A multiplex cytokine assay was used to measure 17 cytokines in the saliva of pediatric patients with burns (n = 20) and healthy controls (n = 20). After the removal of cytokines that had >30% of samples below the assay lower detection limit, six cytokines including IL-1ß, IL-4, IL-7, IL-8, MCP-1, and TNFα were analyzed for association with burns. IL-1ß and IL-4 were found to be significantly elevated in the pediatric burn patients compared to healthy controls. Interestingly, IL-1ß was also significantly elevated in scald burns, compared to contact burns. In addition, biologically meaningful differences in cytokine concentration were identified in patients with different burn characteristics, which warrant further investigation. This exploratory study provides evidence that cytokines can be detected in the saliva of children and that salivary cytokine profiles differ between healthy controls and children with burns. Overall, this study demonstrates the value of saliva for the investigation of cytokines and its potential application in pediatric diagnostics, specifically in situations where blood collection is not appropriate.

Chemical burn to the skin: A systematic review of first aid impacts on clinical outcomes.

Chemical burns can cause deep injury and subsequently significant scarring to the skin. The mechanism and pathophysiology of chemical burns is distinct to thermal burns, and recommended first aid approaches are consequently different. Twenty minutes of cool running water is an effective first aid measure to improve outcomes after thermal burn. For chemical burns to the skin, the recommendations are immediate water lavage for 60 min, removal of contaminated clothing if not stuck to the skin and then covering the wound with a sterile dressing. This review assesses the peer-reviewed literature to find the evidence behind the efficacy of cutaneous chemical burn first aid on short term outcomes such as length of hospital stay, depth of burn and longer-term outcomes such as scarring; in particular, the effect of immediate or early water lavage, and the effect of the duration of water lavage. Ocular chemical burns were not included in this review. The review suggests some evidence to support that the early application of cool water irrigation may reduce length of hospital stay and the extent of scarring. Community education should emphasize that water irrigation is recommended and that the earlier this happens, the better.

The lethal heat dose for 50% primary human fibroblast cell death is 48 °C.

Understanding the effect of heat on skin cells is important for the prevention of burn injury. Knowledge of the heat dose required to kill cells can be used to study the cellular mechanisms involved in thermal injury cell death, to assist with the development of novel burn treatments. In this study, primary human skin dermal fibroblasts were exposed to temperatures from 37 to 54 °C for 1 h and the relative cell viability of heat-treated and control cells was assessed. Cell damage and viability were assessed by light microscopy, MTT assay and live/dead staining. The LD50 for 1 h of heat exposure was 48 °C for primary fibroblasts; and there was evidence that thermal damage to cells begins to occur at 43 °C. This study presents a reproducible method for examining the effect of heat on primary human cells grown in culture on a cellular level and can be used in the future to study the mechanisms behind heat-induced cell death, to inform burn injury prevention efforts and effective post-burn treatment.

Systemic long-term metabolic effects of acute non-severe paediatric burn injury.

A growing body of evidence supports the concept of a systemic response to non-severe thermal trauma. This provokes an immunosuppressed state that predisposes paediatric patients to poor recovery and increased risk of secondary morbidity. In this study, to understand the long-term systemic effects of non-severe burns in children, targeted mass spectrometry assays for biogenic amines and tryptophan metabolites were performed on plasma collected from child burn patients at least three years post injury and compared to age and sex matched non-burn (healthy) controls. A panel of 12 metabolites, including urea cycle intermediates, aromatic amino acids and quinolinic acid were present in significantly higher concentrations in children with previous burn injury. Correlation analysis of metabolite levels to previously measured cytokine levels indicated the presence of multiple cytokine-metabolite associations in the burn injury participants that were absent from the healthy controls. These data suggest that there is a sustained immunometabolic imprint of non-severe burn trauma, potentially linked to long-term immune changes that may contribute to the poor long-term health outcomes observed in children after burn injury.