Burn depth: a review

Nanocellulose significantly reduces number of anesthetics, hospital days, and in-patient dressing changes compared to PU-Foam Dressing: A prospective cohort study in children

BACKGROUND

Pediatric thermal injuries can have profound physical and psychological effects. Long-term care, including wound dressing selection, significantly impacts outcomes. This study compared treatment related variables and long-term results of bacterial nanocellulose (BNC) and polyurethane foam (PU-foam) dressings in pediatric burn care.

METHODS

A prospective cohort study comparing BNC (2018-2020) and PU-foam (2016-2018) in pediatric burn patients. Data included demographics, wound characteristics, infection rates, treatment duration, anesthesia procedures, dressing changes, scar assessments (POSAS, VSS), colorimeter measurements, and quality of life (CDLQI). Regression analyses were performed to correct for differences in burn depth.

RESULTS

After correction for burn depth, BNC showed a shorter hospital stay duration (p = 0.007), a lower number of procedures under general anesthesia (p<0.0001) and a reduced number of inpatient dressing changes (p = 0.006), compared to PU-foam, whereas wound infection rates did not differ between the treatment groups (p = 0.169). Scar outcomes (POSAS, VSS, colorimeter measurements) and quality of life (CDLQI) were comparable for both treatments.

DISCUSSION

BNC dressing benefits include significantly fewer anesthesia procedures, a reduced number of inpatient dressing changes and a shorter hospital stays, supporting the use of BNC dressing. Long-term scar outcomes with BNC are comparable to established dressings like PU-foam. Further randomized trials are necessary to confirm these findings.

Novel multi-spectral short-wave infrared imaging for assessment of human burn wound depth

Burn depth determination is critical for patient care but is currently lacking accuracy. Recent animal studies showed that Short Wave Infrared (SWIR) imaging can distinguish between superficial and deep burns. This is a first human study correlating reflectance of multiple SWIR bands using a SWIR assessment tool (SWAT) with burn depth classifications by surgeons and histology. Burns and adjacent normal skin in 11 patients with thermal injuries were imaged with visual and narrow bands centred at 1200, 1650, 1940 and 2250 nm and biopsies were taken from select areas. Reflectance intensities for each band in 273 regions of interest (ROI) were divided by the normal skin reflectance and combined into three Reflectance Indices (RIs). In addition, burns in ROIs and biopsies were classified by five surgeons and three pathologists, respectively, as superficial partial, deep partial, or full thickness. Results show that for burn depth increase classified by the surgeons, reflectance increased at 1200 and 2250, decreased at 1940, and didn't change at 1650 nm. In contrast, all three RIs increase with burn depth and predict the deep and full depths ROIs representing operable regions (Area Under Curve >0.6507, p < 0.0001). Pathologists' classification matched surgeons' classification of burn category only in eight of 21 biopsies (38.1%), but reflectance at all bands and one RI for all deep partial and full thickness biopsies were larger than in non-biopsy normal and superficial partial thickness ROIs (p < 0.0118). In conclusion, multi-spectral imaging with a new SWAT is a promising approach for evaluation of burn wound depth.

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.

Early Enzymatic Burn Debridement: Results of the DETECT Multicenter Randomized Controlled Trial

Since 1970 surgeons have managed deep burns by surgical debridement and autografting. We tested the hypothesis that enzymatic debridement with NexoBrid would remove the eschar reducing surgery and achieve comparable long-term outcomes as standard of care (SOC). In this Phase 3 trial, we randomly assigned adults with deep burns (covering 3-30% of total body surface area [TBSA]) to NexoBrid, surgical or nonsurgical SOC, or placebo Gel Vehicle (GV) in a 3:3:1 ratio. The primary endpoint was complete eschar removal (ER) at the end of the debridement phase. Secondary outcomes were need for surgery, time to complete ER, and blood loss. Safety endpoints included wound closure and 12 and 24-months cosmesis on the Modified Vancouver Scar Scale. Patients were randomized to NexoBrid (n = 75), SOC (n = 75), and GV (n = 25). Complete ER was higher in the NexoBrid versus the GV group (93% vs 4%; P < .001). Surgical excision was lower in the NexoBrid vs the SOC group (4% vs 72%; P < .001). Median time to ER was 1.0 and 3.8 days for the NexoBrid and SOC respectively (P < .001). ER blood loss was lower in the NexoBrid than the SOC group (14 ± 512 mL vs 814 ± 1020 mL, respectively; P < .0001). MVSS scores at 12 and 24 months were noninferior in the NexoBrid versus SOC groups (3.7 ± 2.1 vs 5.0 ± 3.1 for the 12 months and 3.04 ± 2.2 vs 3.30 ± 2.76 for the 24 months). NexoBrid resulted in early complete ER in >90% of burn patients, reduced surgery and blood loss. NexoBrid was safe and well tolerated without deleterious effects on wound closure and scarring.

Consensus on the treatment of second-degree burn wounds (2024 edition)

Second-degree burns are the most common type of burn in clinical practice and hard to manage. Their treatment requires not only a consideration of the different outcomes that may arise from the dressing changes or surgical therapies themselves but also an evaluation of factors such as the burn site, patient age and burn area. Meanwhile, special attention should be given to the fact that there is no unified standard or specification for the diagnosis, classification, surgical procedure, and infection diagnosis and grading of second-degree burn wounds. This not only poses great challenges to the formulation of clinical treatment plans but also significantly affects the consistency of clinical studies. Moreover, currently, there are relatively few guidelines or expert consensus for the management of second-degree burn wounds, and no comprehensive and systematic guidelines or specifications for the treatment of second-degree burns have been formed. Therefore, we developed the Consensus on the Treatment of Second-Degree Burn Wounds (2024 edition), based on evidence-based medicine and expert opinion. This consensus provides specific recommendations on prehospital first aid, nonsurgical treatment, surgical treatment and infection treatment for second-degree burns. The current consensus generated a total of 58 recommendations, aiming to form a standardized clinical treatment plan.

The Use of Laser Doppler Imaging in Nitric Acid Burns: A Case Report and Literature Review

Laser Doppler imaging (LDI) technology has been validated to assess thermal burn depth by predicting wound healing potential. However, there is no clear evidence for its use in chemical burns. We present a case of an 8% total burn surface area (TBSA) nitric acid burn following an industrial accident, in an otherwise healthy 36-year-old man. LDI assessment was suggestive of poor healing potential of >21 days, warranting surgical management. However, conservative management was opted for based on clinical assessment as the wound eschar appeared thin and more consistent with epithelial staining. Patient follow-up confirmed a total burn healing time of two months, suggesting that the LDI assessment was accurate. A comprehensive literature review was performed using the MEDLINE (PubMed) database to identify animal or clinical studies evaluating the efficacy of LDI in chemical burns. A qualitative synthesis of our findings is presented. We identified two experimental studies in porcine models with sulfur mustard burns, each confirming the accuracy of LDI assessment when compared to the histopathology findings. Limited experimental animal studies on the use of LDI suggest similar validity in chemical burns, and this correlates with the clinical outcome in this case. However, this alone is insufficient to prove its validity and define its role in the assessment of chemical burns. Clinical trials are required to further assess and define the parameters of LDI use and efficacy in this context.

Photographic Evaluation of Burn Depth via Telemedicine: Insights from Iranian Surgeons

Background

The accurate assessment of burn depth is crucial for determining appropriate treatment. Telemedicine has emerged as a promising tool for supporting burn diagnosis and decision-making, as it allows for remote consultation with burn specialists and access to high-quality imaging. The aim of this study was to evaluate the diagnostic capabilities of telemedicine in diagnosing burn depth.

Methods

A total of 15 Iranian surgeons participated in this study; they were presented with 13 images of partial thickness burn ulcers located on the extremities and trunk of patients. The participating surgeons were required to provide their diagnoses of burn type and depth, as well as the necessity of surgical intervention, and their responses were recorded.

Results

Data from 11 participants and 143 responses were analyzed. The average diagnostic accuracy for superficial burns was 79.3%, while for deep burns, it was 13.72%. The mean total diagnostic accuracy was 75.2%.

Conclusion

The results of this study suggest that photographs can be a reliable diagnostic tool for evaluating superficial burns. However, photographs are neither valid nor reliable for assessing burn depth. These findings have important implications for the use of telemedicine in burn diagnosis and indicate that additional diagnostic tools may be necessary for accurate assessment of deep burns.

Temporal trends in burn size estimation and the impact of the NSW Trauma App on estimation accuracy

BACKGROUND

Several studies demonstrated that burn size calculations by referring clinicians are poor. The purpose of this study was to determine if inaccuracies in burn size estimation have improved with time within the same population, and whether widespread roll-out of a smartphone-based TBSA calculator (in the form of the NSW Trauma App) had an impact on accuracy.

METHODS

A review of all burn-injured adult patients transferred to Burn Units from August 2015, following the roll out of the NSW Trauma App, to January 2021 was performed. The TBSA determined by the referring centre was compared with the TBSA calculated by the Burn Unit. This was compared to historical data from the same population between January 2009 and August 2013.

RESULTS

There were 767 adult burn-injured patients transferred to a Burn Unit between 2015 and 2021. The median overall TBSA was 7%. There were 290 patients (37.9%) who had equivalent TBSA calculations by the referring hospital and the Burn Unit. This was a significant improvement compared to the preceding time period (P < 0.005). Overestimation by the referring hospital occurred in 364 cases (47.5%), which was significantly reduced compared to 2009 - 2013 (P < 0.001). Unlike the earlier time period where changes in estimation accuracy were seen in relation to increasing time after the burn injury, burn size estimation accuracy remained relatively consistent in the contemporary time period with no significant change observed (P = 0.86).

CONCLUSIONS

This cumulative, longitudinal study of nearly 1500 adult burn-injured patients over 13 years demonstrates improvements in burn size estimation by referring clinicians over time. It is the largest cohort of patients analysed with respect to burn size estimation and is the first to demonstrate improvements in accuracy of TBSA in association with a smartphone-based app. Adopting this simple strategy into burn retrieval systems will augment early assessment of these injuries and improve outcomes.

Measuring collagen injury depth for burn severity determination using polarization sensitive optical coherence tomography

Determining the optimal treatment course for a dermatologic burn wound requires knowledge of the wound’s severity, as quantified by the depth of thermal damage. In current clinical practice, burn depth is inferred based exclusively on superficial visual assessment, a method which is subject to substantial error rates in the classification of partial thickness (second degree) burns. Here, we present methods for direct, quantitative determination of the depth extent of injury to the dermal collagen matrix using polarization-sensitive optical coherence tomography (PS-OCT). By visualizing the depth-dependence of the degree of polarization of light in the tissue, rather than cumulative retardation, we enable direct and volumetric assessment of local collagen status. We further augment our PS-OCT measurements by visualizing adnexal structures such as hair follicles to relay overall dermal viability in the wounded region. Our methods, which we have validated ex vivo with matched histology, offer an information-rich tool for precise interrogation of burn wound severity and healing potential in both research and clinical settings.

Biomedical engineering aspects of nanocellulose: a review

Cellulose is one of the most abundant renewable biopolymer in nature and is present as major constituent in both plant cell walls as well as synthesized by some microorganisms as extracellular products. In both the systems, cellulose self-assembles into a hierarchical ordered architecture to form micro to nano-fibrillated structures, on basis of which it is classified into various forms. Nanocellulose (NCs) exist as rod-shaped highly crystalline cellulose nanocrystals to high aspect ratio cellulose nanofibers, micro-fibrillated cellulose and bacterial cellulose (BC), depending upon the origin, structural and morphological properties. Moreover, NCs have been processed into diversified products ranging from composite films, coatings, hydrogels, aerogels, xerogels, organogels, rheological modifiers, optically active birefringent colored films using traditional-to-advanced manufacturing techniques. With such versatility in structure-property, NCs have profound application in areas of healthcare, packaging, cosmetics, energy, food, electronics, bioremediation, and biomedicine with promising commercial potential. Herein this review, we highlight the recent advancements in synthesis, fabrication, processing of NCs, with strategic chemical modification routes to tailor its properties for targeted biomedical applications. We also study the basic mechanism and models for biosynthesis of cellulose in both plant and microbial systems and understand the structural insights of NC polymorphism. The kinetics study for both enzymatic/chemical modifications of NCs and microbial growth behavior of BC under various reactor configurations are studied. The challenges associated with the commercial aspects as well as industrial scale production of pristine and functionalized NCs to meet the growing demands of market are discussed and prospective strategies to mitigate them are described. Finally, post chemical modification evaluation of biological and inherent properties of NC are important to determine their efficacy for development of various products and technologies directed for biomedical applications.

Assessing multimodal optical imaging of perfusion in burn wounds

A critical need exists for early, accurate diagnosis of burn wound severity to help identify the course of treatment and outcome of the wound. Laser speckle imaging (LSI) is a promising blood perfusion imaging approach, but it does not account for changes in tissue optical properties that can occur with burn wounds, which are highly dynamic environments. Here, we studied optical property dynamics following burn injury and debridement and the associated impact on interpretation of LSI measurements of skin perfusion. We used spatial frequency domain imaging (SFDI) measurements of tissue optical properties to study the impact of burn-induced changes in these properties on LSI measurements. An established preclinical porcine model of burn injury was used (n = 8). SFDI and LSI data were collected from burn wounds of varying severity. SFDI measurements demonstrate that optical properties change in response to burn injury in a porcine model. We then apply theoretical modeling to demonstrate that the measured range of optical property changes can affect the interpretation of LSI measurements of blood flow, but this effect is minimal for most of the measured data. Collectively, our results indicate that, even with a dynamic burn wound environment, blood-flow measurements with LSI can serve as an appropriate strategy for accurate assessment of burn severity.

The burn injury transfer feedback form: A 16 year Australian statewide review of burn inter-hospital transfer

INTRODUCTION

Modern burn care is centralised, and studies show that early, prompt referral to dedicated burn services improve clinical outcomes. We describe the use of a novel clinical instrument, the burn injury Transfer Feedback Form, to support and educate referring clinicians about the early assessment and management of burn injuries. Since 2005, Transfer Feedback Forms have been completed for all burn-injured patients with inter-hospital transfer to a specialised burn unit in the state of New South Wales (NSW), Australia. The aim of this study was to review physiological, procedural, and system or process issues in the care of both adult and paediatric burn-injured patients needing retrieval and transfer in NSW as identified by the Transfer Feedback Form. Secondary objectives were to determine any significant differences in these parameters between metropolitan and regional or remote referring institutions, and if any improvements occurred in these parameters over time.

METHODS

This was a retrospective analysis of all patients who were transferred to a burn unit in NSW between July 2005 and July 2021 using their prospectively completed Transfer Feedback Forms. Patients were divided into metropolitan and non-metropolitan referral sources based on geographic location. Clinical issues or deficiencies identified during each patient transfer were then classified into various groups. To determine if transfer-related clinical concerns had changed with time, two distinct periods before and after 2015, when the NSW Trauma App was introduced, were analysed. We compared trends in frequency of transfer-related concerns before and after App introduction by using interrupted time series analysis.

RESULTS

A total of 3233 patients had Feedback Forms submitted during the 16-year period. We included 929 children (28.7%) and 2304 adults (71.3%). Transfer-related clinical issues were identified in 904 adults (39.0%) and 484 children (52.0%). In both adult and paediatric patients, the most common transfer-related clinical deficiency was in relation to burn size estimation with 525 patients (43.7%) and 207 patients (30.6%), respectively. Between the time periods analysed, the number of issues arising during inter-hospital transfer fell significantly for both adults (from 46.1% to 26.1%; p < 0.05) and children (from 55.3% to 40.7%; p < 0.05). Segmented regression analysis demonstrated a significant break in the rate of transfer-related clinical issues in 2014 (p < 0.05) and 2015 (p < 0.01) for adults. Accurate body surface area estimations also increased significantly by 53% and 50% for adults and children (p < 0.05 for both), respectively, after 2015.

CONCLUSION

Our analysis indicates that the early care of burn-injured patients undergoing inter-hospital transfer is associated with clinical, technical, and logistical challenges. However, introduction of the burn injury Transfer Feedback Form has been associated with improvements in early burn care by referring centres both temporally and geographically. Smartphone-based applications such as the NSW Trauma App have also probably contributed to these findings. Adopting these simple, inexpensive strategies into burn care systems will augment inter-hospital transfer of burn-injured patients, and improve clinical outcomes.

Evaluation of hyperspectral imaging as a modern aid in clinical assessment of burn wounds of the upper extremity

The most common burn wound assessment continues to be the clinical inspection and the tactile examination, which are subjective and remain challenging even for experienced burn surgeons. Recently, hyperspectral imaging camera systems have been increasingly used to support the evaluation of burn wounds. The aim of our study was to determine if hyperspectral imaging analysis differentiates and objectifies the assessment of burn wounds in burns of the upper extremities. We included 97 superficial partial, deep partial dermal burns, and full thickness burns. Hyperspectral imaging analysis was performed for all burns using proprietary software. The software recorded parameters for tissue oxygenation (StO2), tissue hemoglobin index, and near-infrared perfusion. These values were compared with the recordings for healthy, non-burned skin. We found that hyperspectral imaging analysis effectively differentiates burn wounds and shows the ability to distinguish even superficial partial burns from deep partial burns in the near-infrared perfusion analysis feature. Although, it was not possible to differentiate burn wounds in all features. Currently, it is important to optimize the respective reference values of the individual burn degrees for an objectified assessment.

Role, Development, and Value of Enzymatic Debridement as Integral Component in Initial Treatment of Burn Injuries Exemplified by NexoBrid®

Despite intensive research and increased knowledge over the past decades, the handling of severe burn injuries remains complex and is mainly based on clinical experience. High demands in terms of the diagnosis and choice of therapy often confront clinicians with challenging circumstances. Thus, the treatment of burn injuries has predominantly remained under the responsibility of specialised centres. As a new approach in addition to conventional surgery, enzymatically controlled debridement has come into focus for the treatment of burn injuries over the past years. The efficacy and safety of enzymatic debridement has already been implemented by numerous reputable studies. Promising results from the literature are enhanced by feedback from various conference contributions, intradisciplinary exchanges, and international collaborations. The implementation of enzymatic debridement in initial care management was found to be capable of reforming Standards of Care in numerous burn centres by facilitating treatment determinations and reducing the number of classical surgical interventions. Nevertheless, its use is also subject to certain restrictions as usage has shown limitations concerning efficacy when applied to scalds or pre-treated wounds. Enzymatic debridement shows high efficacy in terms of tissue debridement by combining this feature with the minimisation of collateral damage and a broad field of application in burn injuries. Due to their impressive performance in the treatment of burn injuries, enzyme-based techniques have also attracted attention for the treatment of other pathologies such as chronic wounds and are objects of ongoing research in this field. In this article, we illustrate the significance of enzyme-based treatment in initial burn care and shed some light on the potential value of enzymatic approaches in future burn surgery.

Validity of laser speckle contrast imaging for the prediction of burn wound healing potential

OBJECTIVE

To assess validity of Laser Speckle Contrast Imaging (LSCI) for the measurement of burn wound healing potential (HP) in a burn centre patient population, based on Laser Doppler Imaging (LDI) as reference standard.

METHOD

A single-centre prospective observational cohort study was performed between September-December 2019. A total of 50 burns in 14 patients were included. Imaging and data collection were standardized. Correlation between LSCI and LDI flux values was tested. ROC curves were developed to test the discriminative ability of LSCI between LDI HP categories.

RESULTS

Number of adults and children were equal. Mean total body surface area burnt was 5.5%. Main burn causes were scalds (64%) and flame burns (36%). LSCI set-up and imaging duration was 3 min and 10 s, respectively. LSCI was able to discriminate between wounds with early versus delayed HP (<14 versus ≥14 days) with sensitivity 71% and specificity 95% (p < 0.001). For HP ≤21 versus >21 days, similar sensitivity (74%) and specificity (95%) were found (p < 0.001). Correlations between LSCI and LDI flux values were moderate (<14 days) to absent (>21 days).

CONCLUSION

LSCI shows good validity for the prediction of burn wound HP. It is a highly feasible, patient and physician friendly tool.

Experimental models for controlled burn injuries in rats: a systematic analysis of original methods and burn devices

AIM

Despite a wide variety of models found in literature, choosing the right one can be difficult as many of them are lacking precise methodology. This study aims to analyze and compare original burn models in terms of burn device and technique, parameters, and wound depth assessment.

METHODS

A systematic search was performed according to PRISMA guidelines on studies describing original experimental burn models in rats. The adapted PICO formula and ARRIVE checklist were followed for inclusion and assessment of quality of studies. Characteristics of animals, burn technique, burn parameters and method of histological confirmation of burn depth were recorded.

RESULTS

Twenty-seven studies were included in the final analysis. Most studies used direct contact with skin for burn infliction (n=20). The rat's dorsum was the most common site (n=18). Ten studies used manually controlled burn devices, while ten designed automatic burn devices with control over temperature (n=10), exposure time (n=5), and pressure (n=5). Most studies (n=7) used a single biopsy taken from the center of the wound to confirm burn depth immediately after burn infliction.

CONCLUSION

From the wide variety of burn models in current literature, our study provides an overview of the most relevant experimental burn models in rats aiding researchers to understand what needs to be addressed when designing their burn protocol. Models cannot be compared as burn parameters variate significantly. Assessment of burn depth should be done in a standardized, sequential fashion in future burn studies to increase reproducibility.

The process to obtain reimbursement for enzymatic debridement in clinically deep burns

INTRODUCTION

Burn eschar removal by enzymatic debridement with NexoBrid^® (EDNX) results in a maximum preservation of all viable tissue, which is the main advantage over traditional tangential excision. The authors participated in a marketing authorization holder process to obtain reimbursement from the national health authorities in Belgium.

MATERIAL AND METHODS

The reimbursement process consisted of three phases, as specified by the reimbursement regulations required by the Belgian National Institute for Health and Disability Insurance (NIHDI).

RESULTS

Forty-one patients with clinically deep 2nd and 3rd degree burns, treated with EDNX in two Belgian burn centers, were included in the registry for the first phase of the reimbursement process. The total success rate of the EDNX treatment was 95.1% (39/41). Over half of the burn wounds treated with NexoBrid^® (55.2%) did not require any additional surgical debridement or skin grafting. To obtain definitive reimbursement, an extra 16 patients were included. In this population, 51.4% did not require any surgical intervention. The total success rate of the EDNX debridement in this group was 100%. Based on an estimated market share of 12% and around 75 patients in the third year after final reimbursement, a market access consultant calculated that NexoBrid^® will realize yearly savings for the Belgian Healthcare budget of at least €30.000.

CONCLUSION

Based on the results of this Belgian registry study in combination with the yearly healthcare budget savings, the NIHDI granted a final reimbursement for EDNX treatment in adults, endorsed by the Minister of Health on November 5^th, 2019.

Evaluation of burned hand function after enzymatic debridement

Hand burns are common injuries that can result in long-term impairment of hand function. Enzymatic debridement (ED) prevents damage to the viable dermis due to the procedure's selectivity and has become an option for obtaining an accurate depth assessment and enabling wound re-epithelialization with less skin graft use. We conducted a prospective study from July 2015 to July 2018, which enrolled patients with deep partial-thickness hand burns and treated them with ED using bromelain. After a specified period, we assessed the patients' hand function, using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire and the Michigan Hand Outcomes Questionnaire (MHOQ) to assess their disabilities and activities of daily life, respectively. We assessed the hand joint range of motion using a goniometer and assessed scar quality with the Vancouver Scar Scale (VSS). We analyzed 72 patients with 90 burned hands at 3 months and, at the final assessment, 69 patients with 86 burned hands. Fire was the most common cause of the burns. Bromelain allowed for early debridement (73.6% during the first 24 h). At the 3-month evaluation, the mean DASH and MHOQ scores were 2.35 and 97.9%, respectively, with a high inverse correlation between the 2 types of scores (Spearman's rho, -0.78; p < .001). The mean wrist flexion and extension were 85.7 and 80°, respectively, the mean metacarpophalangeal flexion was 88.3°, the proximal interphalangeal (PIP) flexion was 112.9°, and the thumb opposition was 77°. The mean VSS score was 2.87. At the final evaluation, with a minimum follow-up of 391 days, the mean DASH and MHOQ scores were 0.18 and 99.71%, respectively. ED with bromelain in deep partial-thickness hand burns resulted in normal values at 3 months and at over 1 year of follow-up, with complete restoration of function and quality of life and good scar results.

Treatment of Partial Thickness Burns: A Prospective, Randomized Controlled Trial Comparing Four Routinely Used Burns Dressings in an Ambulatory Care Setting

This prospective, randomized controlled trial study compared the effects of four dressings for adult partial thickness burns, focusing on re-epithelialization time and cost effectiveness. Adults with partial thickness burns meeting inclusion criteria were randomized to either Biobrane™, Acticoat™, Mepilex® Ag, or Aquacel® Ag. Primary endpoint for analysis was >95% re-epithelialization. Incremental cost-effectiveness ratios were calculated based on dressing costs. Dominance probabilities between treatment arms were calculated from bootstrap resampling trial data. One hunderd thirty-one partial thickness burn wounds in 119 patients were randomized. Adjusting for sex, age, smoking status, burn mechanism, TBSA, and first aid adequacy, Mepilex® Ag had a reduced time to re-epithelialization compared to Biobrane™ (IRR: 1.26; 95% CI: 1.07-1.48, P < .01). Economic analysis showed that there was a 99%, 71%, and 53% probability that Mepilex® Ag dominated (cheaper and more effective) Biobrane™, Acticoat™, and Aquacel® Ag, respectively. Mepilex® Ag achieved faster re-epithelialization and better cost effectiveness. Patient satisfaction and comfort seems better with Biobrane™ although not reflected within the end outcome of the healed wound. It is the patients' (after extensive education) and clinicians' choice, level of experience, and availability of products in praxis that will guide the decision as to which the product is used individually on which patient.

A Pilot Study of Negative Pressure Therapy with Autologous Skin Cell Suspensions in a Porcine Model

BACKGROUND

Negative pressure wound therapy (NPWT) is an option for securing meshed split thickness skin grafts (mSTSGs) after burn excision to optimize skin graft adherence. Recently, the use of autologous skin cell suspension (ASCS) has been approved for use in the treatment of burn injuries in conjunction with mSTSGs.To date, limited data exists regarding the impact of NPWT on healing outcomes when the cellular suspension is utilized. It was hypothesized that NPWT would not negatively impact wound healing of ASCS+mSTSG.

MATERIALS AND METHODS

A burn, excision, mSTSG, ASCS ± NPWT model was used. Two Duroc pigs were utilized in this experiment, each with 2 sets of paired burns. Four wounds received mSTSG+ASCS+NPWT through post-operative day 3, and 4 wounds received mSTSG+ACSC+ traditional ASCS dressings. Cellular viability was characterized prior to spraying. Percent re-epithelialization, graft-adherence, pigmentation, elasticity, and blood perfusion and blood vessel density were assessed at multiple time points through 2 weeks.

RESULTS

All wounds healed within 14 days with minimal scar pathology and no significant differences in percent re-epithelialization between NPWT, and non-NPWT wounds were observed. Additionally, no differences were detected for pigmentation, perfusion, or blood vessel density. NPWT treated wounds had less graft loss and improved elasticity, with elasticity being statistically different.

CONCLUSIONS

These data suggest the positive attributes of the cellular suspension delivered are retained following the application of negative pressure. Re-epithelialization, revascularization, and repigmentation are not adversely impacted. The use of NPWT may be considered as an option when using ASCS with mSTSGs for the treatment of full-thickness burns.

First preliminary Clinical Experiences using Hyperspectral Imaging for Burn Depth Assessment of Hand Burns

The accurate assessment of burn wounds is challenging but crucial for correct diagnosis and following therapy. The most frequent technique to evaluate burn wounds remains the clinical assessment often subjective depending on the experience of the physician. Hyperspectral Imaging is intended to counteract this subjective diagnosis by an accurate and objective analysis of perfusion parameters. The purpose of this study was to analyse the ability of technical burn depth assessment and to investigate a possible link between a certain value to burn depth versus value of healthy skin references.

METHODS

A total of 118 subjects were included in this study between July 2017 and July 2019. 74 images with dorsal hand burns and 44 images of healthy skin on the dorsal hand as control group were analysed. In Hyperspectral Imaging recordings burn wounds were analysed with special interest to wound centre, intermediate zone, and wound margin.

RESULTS

Significant results were determined for the differentiation between superficial partial burns and healthy skin. Furthermore, the distinction of full thickness burns was significantly possible.

CONCLUSION

Currently, it cannot be shown that the use of Hyperspectral Imaging technology significantly assesses the actual burn depth of thermal wounds of the dorsal hand reliably. However, the results show tendencies to improved analysis for differentiations supporting physicians in early objective optimal treatment selection.

Evidence Based Burn Depth Assessment Using Laser-Based Technologies: Where Do We Stand?

Early clinical assessment of burn depth and associated healing potential (HP) remains extremely challenging, even for experienced surgeons. Inaccurate diagnosis often leads to prolonged healing times and unnecessary surgical procedures, resulting in incremental costs, and unfavorable outcomes. Laser Doppler imaging (LDI) is currently the most objective and accurate diagnostic tool to measure blood flow and its associated HP, the main predictor for a patient's long-term functional and aesthetic outcome. A systematic review was performed on non-invasive, laser-based methods for burn depth assessment using skin microcirculation measurements to determine time to healing: Laser Doppler flowmetry (LDF), LDI and laser speckle contrast imaging (LSCI). Important drawbacks of single point LDF measurements are direct contact with numerous small points on the wound bed and the need to carry out serial measurements over several days. LDI is a fast, "non-contact," single measurement tool allowing to scan large burned areas with a 96% accuracy. LDI reduces the number of surgeries, improves the functional and aesthetic outcome and is cost-effective. There is only limited evidence for the use of LSCI in burn depth assessment. LSCI still needs technical improvements and scientific validation, before it can be approved for reliable burn assessment. LDI has proven to be invaluable in determining the optimal treatment of a burn patient. For unclear reasons, LDI is still not routinely used in burn centers worldwide. Additional research is required to identify potential "barriers" for universal implementation of this evidence-based burn depth assessment tool.

The Use of Visible-Light Hyperspectral Imaging in Evaluating Burn Wounds: A Case Report

Burn depth is a critical factor in determining the healing potential of a burn as the extent of injury ultimately guides overall treatment. Visible-Light Hyperspectral Imaging is an FDA-approved, noninvasive, and noncontrast imaging technology that uses light waves within the visible spectrum to evaluate skin and superficial soft tissue perfusion. In this case report, visible-light hyperspectral imaging was used to evaluate a 37-year-old male who presented to the Emergency Department with a thermal burn of the trunk, back, and right upper extremity. Images were taken at initial evaluation, 6 hours postinjury, and again during daily dressing changes until hospital day 5 when the patient underwent surgical debridement. In this patient, operative treatment was postponed until 89.7 hours postinjury, at which point the clinical examination showed clear visual demarcation in regions of irreversible damage. Comparatively, visible-light hyperspectral imaging analysis of the permanently injured tissue demonstrated acute but varying changes in both oxygenated hemoglobin and deoxygenated hemoglobin at the time of initial evaluation. The most dramatic change in tissue oxygenation occurred between 6.5 and 39.3 hours, demonstrating visible-light hyperspectral imaging's ability to detect significant differences in oxygenation values between areas of second-degree superficial burns and areas of second-degree deep and third-degree burns in the acute period. The data suggest that the utilization of visible-light hyperspectral imaging in this 6.5- to 39.3-hour window may help predict final burn depth before clinical assessment, potentially allowing for surgical intervention within the first 48 hours following injury.

A Framework for Automatic Burn Image Segmentation and Burn Depth Diagnosis Using Deep Learning

Burn is a common traumatic disease with high morbidity and mortality. The treatment of burns requires accurate and reliable diagnosis of burn wounds and burn depth, which can save lives in some cases. However, due to the complexity of burn wounds, the early diagnosis of burns lacks accuracy and difference. Therefore, we use deep learning technology to automate and standardize burn diagnosis to reduce human errors and improve burn diagnosis. First, the burn dataset with detailed burn area segmentation and burn depth labelling is created. Then, an end-to-end framework based on deep learning method for advanced burn area segmentation and burn depth diagnosis is proposed. The framework is firstly used to segment the burn area in the burn images. On this basis, the calculation of the percentage of the burn area in the total body surface area (TBSA) can be realized by extending the network output structure and the labels of the burn dataset. Then, the framework is used to segment multiple burn depth areas. Finally, the network achieves the best result with IOU of 0.8467 for the segmentation of burn and no burn area. And for multiple burn depth areas segmentation, the best average IOU is 0.5144.

Quantitative Evaluation of Burn Injuries Based on Electrical Impedance Spectroscopy of Blood with a Seven-Parameter Equivalent Circuit

A quantitative and rapid burn injury detection method has been proposed based on the electrical impedance spectroscopy (EIS) of blood with a seven-parameter equivalent circuit. The degree of burn injury is estimated from the electrical impedance characteristics of blood with different volume proportions of red blood cells (RBCs) and heated red blood cells (HRBCs). A quantitative relationship between the volume portion H_HCT of HRBCs and the electrical impedance characteristics of blood has been demonstrated. A seven -parameter equivalent circuit is employed to quantify the relationship from the perspective of electricity. Additionally, the traditional Hanai equation has been modified to verify the experimental results. Results show that the imaginary part of impedance Z_Imt under the characteristic frequency (f_c) has a linear relationship with H_HCT which could be described by Z_Imt = −2.56H_HCT − 2.01 with a correlation coefficient of 0.96. Moreover, the relationship between the plasma resistance R_p and H_HCT is obtained as R_p = −7.2H_HCT + 3.91 with a correlation coefficient of 0.96 from the seven -parameter equivalent circuit. This study shows the feasibility of EIS in the quantitative detection of burn injury by the quantitative parameters Z_Imt and R_p, which might be meaningful for the follow-up clinical treatment for burn injury.

The LDI Enigma, Part I: So much proof, so little use

INTRODUCTION

Laser Doppler imaging (LDI) is still not an ubiquitous part of burn care worldwide despite reported accuracy rates of more than 95%, which is significantly higher than clinical assessment alone (50-75%). The aims of Part I of this survey study are: to identify the most important barriers for the use of LDI and to provide useful recommendations for efficient implementation in routine burn care. The actual interpretation and use of LDI measurements is discussed in the Enigma Part II article.

MATERIAL AND METHODS

1. Informative interviews with 15 representatives of burn centers without LDI. 2. A survey among 51 burn centers with LDI by means of an extensive questionnaire. 3. In-depth interviews with 21 of the participating centers.

RESULTS

1. All 15 centers without LDI indicated that cost of purchase in combination with maintenance of the LDI device, as well as personnel costs were the reason for not buying, while 12 (80%) also rated the current scientific evidence as insufficient. 2. Twenty-seven burn centers with an LDI (53%) participated and filled in almost the entire questionnaire. In 5 centers, cost delayed the purchase of LDI. The hospital/department paid for the LDI device in 62% of the burn centers and in 88% also for maintenance and salaries. The LDI operators were mainly surgeons (47%) or nurses (42%). In more than half of the burn centers (52%), between 2 and 5 people were trained and certified to use an LDI. In 50% of burn centers, the interpretation of the LDI scan was done by the same person doing the actual measurements. Eighty-nine percent of the burn centers considered the accuracy of the LDI scan as mainly to almost completely accurate. In case of real discrepancy between clinical diagnosis and LDI, in 48% of the burn centers (13/27) the surgeon still relied more on the clinical diagnosis despite reporting this high or almost complete accuracy rate of the LDI.

CONCLUSIONS

Barriers for the routine implementation of LDI were: 1. cost of purchasing and using an LDI combined with health care systems that inadequately reimburse non-surgical management; 2. lack of awareness of or ongoing skepticism towards the scientific evidence supporting LDI use; and 3. organizational constraints combined with logistical limitations. Our recommendations for wider use of LDI technology include: 1. a cost-effective reimbursement of LDI use combined with a more appropriate valuation of expert conservative management compared to surgical therapy; 2. increased use of LDI for every mixed depth burn and; 3. specialized LDI teams to improve burn procedural flexibility and to enable embedding LDI use in the burn care routine. Implementing these measures would promote the highest standards for LDI measurements and interpretation resulting in optimal care with mutual benefits for the hospital, for burn care teams and, most importantly, for the patients.

Evolution of ischemia and neovascularization in a murine model of full thickness human wound healing

Translation of wound healing research is limited by the lack of an appropriate animal model, due to the anatomic and wound healing differences in animals and humans. Here, we characterize healing of grafted, full-thickness human skin in an in vivo model of wound healing. Full-thickness human skin, obtained from reconstructive operations, was grafted onto the dorsal flank of NOD.Cg-KitW41J Tyr + Prkdcscid Il2rgtm1Wjl /ThomJ mice. The xenografts were harvested 1 to 12 weeks after grafting, and histologic analyses were completed for viability, neovascularization, and hypoxia. Visual inspection of the xenograft shows drying and sloughing of the epidermis starting at week four. By week 12, the xenograft appears healed but has lost 63.05 ± 0.24% of the initial graft size. There is histologic evidence of epidermolysis as early as 2 weeks, which progresses until week 4, when new epidermis appears from the wound edges. Epidermal regeneration is complete by week 12, although the epidermis appears hypertrophied. An initial increase of infiltrating immune mouse cells into the xenograft normalizes to baseline 6 months after grafting. Neovascularization, as evidenced by positive staining for the proteins human CD31 and alpha smooth muscle actin, is present as early as 2 weeks after grafting at the interface between the xenograft and the mouse tissue. CD31 and alpha smooth muscle actin staining increased throughout the xenograft over the 12 weeks, leading to greater viability of the tissue. Likewise, there is increased Hypoxia Inducible Factor 1-alpha expression at the interface of viable and nonviable tissue, which suggest a hypoxia-driven process causing early graft loss. These findings illustrate human skin wound healing in an ischemic environment, providing a timeline for use of full thickness human skin after grafting in a murine model to study mechanisms underlying human skin wound healing.

Coming to Consensus: What Defines Deep Partial Thickness Burn Injuries in Porcine Models?

Deep partial thickness burns are clinically prevalent and difficult to diagnose. In order to develop methods to assess burn depth and therapies to treat deep partial thickness burns, reliable, accurate animal models are needed. The variety of animal models in the literature and the lack of precise details reported for the experimental procedures make comparison of research between investigators challenging and ultimately affect translation to patients. They sought to compare deep partial thickness porcine burn models from five well-established laboratories. In doing so, they uncovered a lack of consistency in approaches to the evaluation of burn injury depth that was present within and among various models. They then used an iterative process to develop a scoring rubric with an educational component to facilitate burn injury depth evaluation that improved reliability of the scoring. Using the developed rubric to re-score the five burn models, they found that all models created a deep partial thickness injury and that agreement about specific characteristics identified on histological staining was improved. Finally, they present consensus statements on the evaluation and interpretation of the microanatomy of deep partial thickness burns in pigs.

Optical imaging of collagen fiber damage to assess thermally injured human skin

Surgery is the definitive treatment for burn patients who sustain full-thickness burn injuries. Visual assessment of burn depth is made by the clinician early after injury but is accurate only up to 70% of the time among experienced surgeons. Collagen undergoes denaturation as a result of thermal injury; however, the association of collagen denaturation and cellular death in response to thermal injury is unknown. While gene expression assays and histologic staining allow for ex vivo identification of collagen changes, these methods do not provide spatial or integrity information in vivo. Thermal effects on collagen and the role of collagen in wound repair have been understudied in human burn models due to a lack of methods to visualize both intact and denatured collagen. Hence, there is a critical need for a clinically applicable method to discriminate between damaged and intact collagen fibers in tissues. We present two complementary candidate methods for visualization of collagen structure in three dimensions. Second harmonic generation imaging offers a label-free, high-resolution method to identify intact collagen. Simultaneously, a fluorophore-tagged collagen-mimetic peptide can detect damaged collagen. Together, these methods enable the characterization of collagen damage in human skin biopsies from burn patients, as well as ex vivo thermally injured human skin samples. These combined methods could enhance the understanding of the role of collagen in human wound healing after thermal injury and potentially assist in clinical decision-making.

The Efficacy of Five Different Wound Dressings on Some Histological Parameters in Children With Partial-Thickness Burns

An ideal dressing should ensure that the wound remains moist with exudates but not macerated. Currently, there is no dressing available to suit all wounds, at all stages of the healing process. Although silver-containing dressings are the gold standard for burn wound care, few high-level trials have been completed comparing the clinical utilities of these dressings. In our study, five different types of wound dressings: carboxymethyl cellulose hydrofiber dressing with ionized silver (CMCH-Ag), polyethylene-polyethylene terephthalate aqua fiber dressing with elementary silver (PPAF-Ag), calcium alginate (CA), calcium + zinc alginate (CZA), and 0.2% nitrofurazone-embedded (NF) gauze dressings were compared in regard to histopathological parameters. Children aged between 0 and 18 years with small or middle-sized partial-thickness burns that affected less than 30% of the total body surface area were included in this study. The study groups (CMCH-Ag, PPAF-Ag, CA, and CZA) and the control group (NF) were randomly attained. Wound healing was evaluated by punch biopsies on the 21st day. The thickness of the stratum corneum and the epithelium, the number of papillae, and the papillary length were calculated and compared. The histological parameters of healing, except the stratum corneum thickness, did not show any statistical significance among the groups (P &gt; .05). The dressings that included silver, calcium, or zinc showed useful and similar effects in noninfective burn wounds when compared with nitrofurazone-only dressings. Thus, it may be concluded that silver-containing wound dressings should not be considered as the gold standard in noninfective partial-thickness burn wounds in children.

Investigating the effects of walnut ointment on non-healing burn wounds

Effective treatments for non-healing burn wounds are an unmet need for 95% of burn sufferers. Approaches currently available to treat non-healing burn wounds are not satisfactory due to undesirable side-effects or expense. The anti-oxidation and antibacterial activities of walnuts are recommended for treating chronic diseases. Walnut ointment has been developed and successfully applied to treat non-healing burn wounds in our hospital for decades. We report herein a detailed retrospective case review examining patients' response to the walnut ointment. The walnut ointment has shortened healing time of non-healing burn wounds and improved clinical outcomes. In order to investigate the mechanism of action, walnut ointment has been applied on wounds of porcine full-thickness burn wound models. Histological and immunohistochemical analysis indicated our walnut ointment supports wound healing through promoting keratinocyte proliferation and differentiation. Taken together, we recommend the walnut ointment offers an effective and economical treatment for patients presenting with non-healing burn wounds.

A Systematic Review on Classification, Identification, and Healing Process of Burn Wound Healing

Because of the intrinsic complexity, the classification of wounds is important for the diagnosis, management, and choosing the correct treatment based on wound type. Generally, burn injuries are classified as a class of wounds in which injury is caused by heat, cold, electricity, chemicals, friction, or radiation. On the other hand, wound healing is a complex process, and understanding the biological trend of this process and differences in the healing process of different wounds could reduce the possible risk in many cases and greatly reduce the future damage to the injured tissue and other organs. The aim of this review is to provide a general perspective for the burn wound location among the other types of injuries and summarizing as well as highlighting the differences of these types of wounds with emphasizing on factors affecting thereof.

Early visualization of skin burn severity using a topically applied dye-loaded liquid bandage

Skin burns are a significant source of injury in both military and civilian sectors. They are especially problematic in low resource environments where non-fatal injuries can lead to high morbidity rates, prolonged hospitalization, and disability. These multifaceted wounds can be highly complex and must be quickly diagnosed and treated to achieve optimal outcomes. When the appropriate resources are available, the current gold standard for assessing skin burns is through tissue punch biopsies followed by histological analysis. Apart from being invasive, costly, and time-consuming, this method can suffer from heterogeneous sampling errors when interrogating large burn areas. Here we present a practical method for the early visualization of skin burn severity using a topically applied fluorescein-loaded liquid bandage and an unmodified commercial digital camera. Quantitative linear mixed effects models of color images from a four day porcine burn study demonstrate that colorimetric changes within the HSB colorspace can be used to estimate burn depth severity immediately after burning. The finding was verified using fluorescence imaging, tissue cross-sectioning, and histopathology. This low-cost, rapid, and non-invasive color analysis approach demonstrates the potential of dye-loaded liquid bandages as a method for skin burn assessment in settings such as emergency medicine triage and low resource environments.

Releasing Burn-Induced Compartment Syndrome by Enzymatic Escharotomy-Debridement: A Case Study

Burn-induced compartment syndrome represents a serious and acute condition in deep circumferential burns of the extremities which, if left untreated, can cause severe complications. The surgical escharotomy that releases the high subdermal pressure is the therapeutic treatment of choice for burn-induced compartment syndrome. Guidelines for escharotomy indications and timing include pressure greater than 30 mm Hg and 6 Ps (Pain, Pallor, Paresthesia, Paralysis, Pulseless, and Poikilothermia). Nevertheless, despite the need for an early as possible pressure release, escharotomy is often delayed when a capable surgeon is not available, or if the indication is not completely clear to justify potential risks associated with surgical escharotomy. Early treatment of circumferential burns of the extremities with a Bromelain-based enzymatic agent NexoBrid® may represent a less traumatic and invasive procedure to reduce intra-compartmental pressure, replacing surgical escharotomy. This case study of 23 patients describes the variation of compartmental pressure in patients with circumferential burns of the extremities treated with NexoBrid® enzymatic escharotomy-debridement. All the patients were treated with NexoBrid® within 2 to 22 hours post-injury in our Burn Intensive Care Center. The excessive pressure recorded before treatment returned to normal below 30 mm Hg and an approximately 60% reduction of the compartmental pressure was observed in most cases within 1 hour from NXB application. On NexoBrid® removal after 4 hours complete debridement-escharotomy of the burns was achieved. Enzymatic escharotomy-debridement appears to be a useful and safe method to reduce postburn compartmental pressure. Additional randomized, well-controlled powered studies are needed to further support these results.

Short-wave infrared light imaging measures tissue moisture and distinguishes superficial from deep burns

Existing clinical approaches and tools to measure burn tissue destruction are limited resulting in misdiagnosis of injury depth in over 40% of cases. Thus, our objective in this study was to characterize the ability of short-wave infrared (SWIR) imaging to detect moisture levels as a surrogate for tissue viability with resolution to differentiate between burns of various depths. To accomplish our aim, we constructed an imaging system consisting of a broad-band Tungsten light source; 1,200-, 1,650-, 1,940-, and 2,250-nm wavelength filters; and a specialized SWIR camera. We initially used agar slabs to provide a baseline spectrum for SWIR light imaging and demonstrated the differential absorbance at the multiple wavelengths, with 1,940 nm being the highest absorbed wavelength. These spectral bands were then demonstrated to detect levels of moisture in inorganic and in vivo mice models. The multiwavelength SWIR imaging approach was used to diagnose depth of burns using an in vivo porcine burn model. Healthy and injured skin regions were imaged 72 hours after short (20 seconds) and long (60 seconds) burn application, and biopsies were extracted from those regions for histologic analysis. Burn depth analysis based on collagen coagulation histology confirmed the formation of superficial and deep burns. SWIR multispectral reflectance imaging showed enhanced intensity levels in long burned regions, which correlated with histology and distinguished between superficial and deep burns. This SWIR imaging method represents a novel, real-time method to objectively distinguishing superficial from deep burns.

Preliminary Assessment of Burn Depth by Paper-Based ELISA for the Detection of Angiogenin in Burn Blister Fluid-A Proof of Concept

Rapid assessment of burn depth is important for burn wound management. Superficial partial-thickness burn (SPTB) wounds heal without scars, but deep partial-thickness burn (DPTB) wounds require a longer healing time and have a higher risk of scar formation. We previously found that DPTB blister fluid displayed a higher angiogenin level than SPTB blister fluid by conventional ELISA. In this study, we developed a paper-based ELISA (P-ELISA) technique for rapid assessment of angiogenin concentration in burn blister fluid. We collected six samples of SPTB blister fluid, six samples of DPTB blister fluid, and seven normal healthy serum samples for analysis. We again chose ELISA to measure and compare angiogenin levels across all of our samples, but we developed a P-ELISA tool and compared sample results from that tool to the results from conventional ELISA. As with conventional ELISA, DPTB blister fluid displayed higher angiogenin levels than SPTB in P-ELISA. Furthermore, our P-ELISA results showed a moderate correlation with conventional ELISA results. This new diagnostic technique facilitates rapid and convenient assessment of burn depth by evaluating a key molecule in burn blister fluid. It presents a novel and easy-to-learn approach that may be suitable for clinically determining burn depth with diagnostic precision.

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.

Full-field burn depth detection based on near-infrared hyperspectral imaging and ensemble regression

The accurate and instant diagnosis of burn severity is always the key point of optimal wound management and clinical treatment. However, the accuracy of burn depth assessment is low via visual inspection and lacks a quantitative measurement. In this work, a full-field burn depth detection system is proposed using the near-infrared hyperspectral imaging with the ensemble regression. The rotational feature subspace ensemble regression is introduced to establish a complex regression model between the hyperspectral imaging data and the burn depth. By the in vivo measurement of a porcine model, the method can get the average relative error about 7% for the burn depth measurement, which demonstrates that the proposed method can perform an accurate full-field assessment of burn depth and provide more practical references for clinicians.

Burn wound classification model using spatial frequency-domain imaging and machine learning

Accurate assessment of burn severity is critical for wound care and the course of treatment. Delays in classification translate to delays in burn management, increasing the risk of scarring and infection. To this end, numerous imaging techniques have been used to examine tissue properties to infer burn severity. Spatial frequency-domain imaging (SFDI) has also been used to characterize burns based on the relationships between histologic observations and changes in tissue properties. Recently, machine learning has been used to classify burns by combining optical features from multispectral or hyperspectral imaging. Rather than employ models of light propagation to deduce tissue optical properties, we investigated the feasibility of using SFDI reflectance data at multiple spatial frequencies, with a support vector machine (SVM) classifier, to predict severity in a porcine model of graded burns. Calibrated reflectance images were collected using SFDI at eight wavelengths (471 to 851 nm) and five spatial frequencies (0 to 0.2  mm  -  1). Three models were built from subsets of this initial dataset. The first subset included data taken at all wavelengths with the planar (0  mm  -  1) spatial frequency, the second comprised data at all wavelengths and spatial frequencies, and the third used all collected data at values relative to unburned tissue. These data subsets were used to train and test cubic SVM models, and compared against burn status 28 days after injury. Model accuracy was established through leave-one-out cross-validation testing. The model based on images obtained at all wavelengths and spatial frequencies predicted burn severity at 24 h with 92.5% accuracy. The model composed of all values relative to unburned skin was 94.4% accurate. By comparison, the model that employed only planar illumination was 88.8% accurate. This investigation suggests that the combination of SFDI with machine learning has potential for accurately predicting burn severity.

Laser-based Techniques for Microcirculatory Assessment in Orthopedics and Trauma Surgery: Past, Present, and Future

: Microcirculatory integrity and proper function are the cornerstones to tissue nourishment and viability. In the clinical environment extended immobility, injuries, and inflammatory reactions demand local microcirculatory adaption to provide adequate supply. Assessment of endothelial adjustment capability and microcirculatory perfusion status, as direct or surrogate markers of disease, are therefore of uttermost interest to the treating physician. Given the simple, noninvasive, nonradiating nature of laser-based techniques for bedside or intraoperative microcirculatory perfusion assessment, this article's objective is to present a comprehensive overview of available techniques, their technological aspects, and current application. Advantages of individual methods are pointed out and compared with each other. The areas of medical utilization relevant to orthopedics and trauma surgery are exemplified and their available evidence elaborated. A particular focus is put on laser speckle contrast imaging, with its current and future influence on medical practice.

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.

The optimal timing of outpatient Biobrane™ application for superficial and mid dermal partial thickness burns: Evidence for the '12-hour rule'

BACKGROUND

Biobrane™ is a skin substitute used for the definitive management of partial thickness burns. No studies have examined the optimal timing of Biobrane™ application in this setting. The purpose of this study was to determine whether there was a clinically significant difference in applying Biobrane to a superficial and mid dermal partial thickness burn within 12h after burn.

METHODS

From August 2016-February 2017, 29 consecutive superficial and mid dermal partial thickness burn injuries were prospectively treated with Biobrane™ within 12h of the injury. This 'early Biobrane™' cohort was compared to a historical cohort of 148 patients who were treated with Biobrane™ for superficial and mid dermal burns after 12h after injury during 2015 to 2016. Multivariate regression analysis was used to determine the difference in time to re-epithelialisation and number of outpatient visits between the two cohorts.

RESULTS

In the 'early Biobrane™' group, the mean TBSA was 3.5±2.7%. and the mean time to Biobrane™ application was 7.1±2.7h after burn injury. The mean time to re-epithelialisation in this group was 9.1±3.0 days, and no patients underwent skin grafting. In the 'delayed Biobrane™' group, the mean TBSA was 2.6±2.8% and the mean time to Biobrane™ application was 35.1±21.4h. The mean time to re-epithelialisation was 14.8±8.7 days, with 3 patients undergoing skin grafting. Regression analysis demonstrated a statistically significant 63% reduction in time to re-epithelialisation (95% CI=0.23-0.60; P<0.0001) with early Biobrane™ application.

CONCLUSION

Patients treated with application of Biobrane™ within 12h of superficial and mid dermal partial thickness burns have a statistically significant reduction in healing time when compared to patients treated with standard Biobrane™ practice.

Small separation diffuse correlation spectroscopy for measurement of cerebral blood flow in rodents

Diffuse correlation spectroscopy (DCS) has shown promise as a means to non-invasively measure cerebral blood flow in small animal models. Here, we characterize the validity of DCS at small source-detector reflectance separations needed for small animal measurements. Through Monte Carlo simulations and liquid phantom experiments, we show that DCS error increases as separation decreases, although error remains below 12% for separations > 0.2 cm. In mice, DCS measures of cerebral blood flow have excellent intra-user repeatability and strongly correlate with MRI measures of blood flow (R = 0.74, p<0.01). These results are generalizable to other DCS applications wherein short-separation reflectance geometries are desired.

Hyperspectral index-based metric for burn depth assessment

Burn depth objective classification is of paramount importance for decision making and treatment. Despite the wide variety of burn depth assessment methods tested so far, none of them have gained wide clinical application. Here, we introduce a new approach for burn depth assessment based on hyperspectral imaging combined with a spectral index-based technique that exploits specific spectral bands to map skin areas with different burn degrees. The spectral index amplifies the contrast between normal skin and areas with different degrees of burn, taking advantage of the differences in spectral amplitudes that occur as a result of the morphological and physiological changes occurring in burned skin. We demonstrate that by using the new measurable spectral index, it is possible to generate accurate burn classification maps showing spatial distribution of burn types in the affected body areas, facilitating the decision-making process and prognosis evaluation. The results highlight the potential of the new hyperspectral metric in the field of burn depth classification and its applicability in hospital settings seems promising.