Deep Partial Thickness Burns Research Articles

An open-label, prospective, randomized, controlled, multicenter, phase 1b study of StrataGraft skin tissue versus autografting in patients with deep partial-thickness thermal burns

ObjectiveThis open-label, controlled, randomized study assessed the safety, tolerability, and efficacy of StrataGraft tissue compared to autograft in the treatment of deep partial-thickness (DPT) burns. MethodsThirty subjects with DPT thermal burns (3%–43% total body surface area) were treated with StrataGraft tissue as follows: cohort 1, ≤220 cm2 refrigerated tissue; cohort 2, ≤440 cm2 refrigerated tissue; and cohort 3, ≤440 cm2 cryopreserved tissue. On each subject, two comparable areas of DPT burn were randomized to receive StrataGraft tissue or autograft. Coprimary end points were the percent area of the StrataGraft tissue treatment site undergoing salvage autografting by Day 28 and wound closure of treatment sites by 3 months. ResultsBy Day 28, no StrataGraft tissue treatment sites underwent autografting. By 3 months, 93% and 100% of the StrataGraft tissue and autograft treatment sites achieved complete wound closure, respectively. No significant differences in observer total and overall opinion POSAS scores between StrataGraft tissue and autograft treatment sites were observed at any timepoint. The most common adverse event was pruritus (17%). ConclusionsStrataGraft tissue treatment of DPT thermal burns reduced the need for autograft, resulted in wound closure and treatment-site cosmesis comparable to that of autograft, and was well tolerated.

Use of NexoBrid for Treatment of Acute Deep Partial and Full Thickness Burn Injuries

Use of NexoBrid for Treatment of Acute Deep Partial and Full Thickness Burn Injuries

Adipose-derived stem cells-induced burn wound healing and regeneration of skin appendages in a novel skin island rat model.

The study of effectiveness of adipose-derived stem cells (ASCs) in treating burn wounds is still a developing field. The process of wound contraction in areas of loose skin is a major confounding factor in the evaluation and study of burn wound healing in animal models. To evaluate the effect of local ASCs administration, deep partial thickness burn wounds were induced by 30 s application of hot copper plates in a novel skin island burn wound rat model to avoid interference from primary wound contraction. Skin islands were divided into two treatment groups-control group (n = 9) injected with PBS and ASCs-treated group (n = 9) injected with 5 × 10 ASCs intradermally. Progress in wound healing was checked at regular intervals after injury (on 1st, 2nd, 3rd, and 4th week) by measuring the mean wound area and analyzing the wound histologically and immunohistochemically, after unstitching the overlaying skin to expose the skin island. It was found that local intradermal injection of ASCs improved burn wound healing at all given time points when compared with control groups, especially in the first 2 weeks (p < 0.05). The percentage of live follicles increased gradually in the ASCs-treated groups compared with control groups between the 3rd and 4th weeks (p < 0.05). The vascular density and proliferating cell nuclear antigen index were also significantly increased in the ASCs-treated groups. Thus, in this study, a novel burn wound rat model with reduced interference from wound contraction has been put forth to investigate the therapeutic effects of local administration of ASCs on burn wound healing. Local injection of ASCs not only improved burn wound recovery but also enhanced angiogenesis and skin appendage regeneration.

Early and late-recorded predictors of health-related quality of life of burn patients on long-term follow-up

BackgroundUnintentional and intentional burn injuries vary across age groups, gender, income, and global region. In high-income countries, the trend over the last several years has been a reduction in burn incidence, burn severity, length of hospital stay, and mortality rate. However, there is a lack of data on predictors of the health-related quality of life (HRQoL) of major burn survivors extending beyond a follow-up period of 10 years. Patients and methodsThis single-center cross-sectional study is considering 42 long-term severe burn survivors with deep partial thickness burns and an affected total body surface area (TBSA) of ≥20%. For study eligibility design a minimum follow-up of 10 years was obligatory. Entitled individuals were asked to fill in the generic Short Form 36 (SF-36) questionnaire. The physical (PCS) and mental (MCS) component scores of the SF-36 were used as the primary outcome variables. Putative predictor variables were drawn from medical records. Burn-specific functionality and scar tissue quality were assessed using the Burn Specific Health Scale-Brief (BSHS-B) questionnaire and the Patient and Observer Scar Assessment Scale (POSAS), respectively. Correlation between putative predictor variables and SF-36 norm scores were evaluated by Pearson- and Point-Biserial correlation as well as multivariate linear regression. The SF-36 norm scores were compared to the general German population. ResultsMean follow-up was 14 (±3) years with a minimum and maximum of 10 and 28 years, respectively. Mean age at the time of the incident was 37 (±17) years. The majority of individuals were male (74%). The mean burn size was 39 (±17) % (TBSA) with 76% of the individuals showing a full thickness burn.SF-36 norm scores were not statistically different from the general population. Statistically significant independent predictor variables of the physical summary score were: age at the time of the injury (−0.381), time since injury (−0.466), length of hospital stay (−0.356), limb amputation (−0.318), unemployment (−0.433), work (0.593), hand function (0.601), body image (0.518), affect (0.355), simple abilities (0.602), burns involving the hands (−0.339) and back (−0.343), POSAS patient- (−0.521) and observer scores (−0.483). In multivariate analysis, work (4.315), the POSAS Score (−2.082) and the age at the time of the incident (−0.242) were statistically significant predictors. Statistically significant independent predictor variables of the mental summary score were: duration of mechanical ventilation (−0.459), hand function (0.415), body image (0.502), sexual activity (0.625), social support (0.542), burns involving the back (−0.315) and affect (0.692). In multivariate analysis, affect (13.844) and the length of mechanical ventilation (−0.115) were statistically significant independent predictor variables. ConclusionTen years after the burn incident, the quality of life was on average comparable to the one in the general population. Multiple variables seem to influence the physical and mental long-term outcome. Herein presented data may support in adapting and designing follow-up strategies tailored to a patient’s burn-specific circumstances.

Temporal shifts in the mycobiome structure and network architecture associated with a rat (Rattus norvegicus) deep partial-thickness cutaneous burn.

With a diverse physiological interface to colonize, mammalian skin is the first line of defense against pathogen invasion and harbors a consortium of microbes integral in maintenance of epithelial barrier function and disease prevention. While the dynamic roles of skin bacterial residents are expansively studied, contributions of fungal constituents, the mycobiome, are largely overlooked. As a result, their influence during skin injury, such as disruption of skin integrity in burn injury and impairment of host immune defense system, is not clearly delineated. Burn patients experience a high risk of developing hard-to-treat fungal infections in comparison to other hospitalized patients. To discern the changes in the mycobiome profile and network assembly during cutaneous burn-injury, a rat scald burn model was used to survey the mycobiome in healthy (n = 30) (sham-burned) and burned (n = 24) skin over an 11-day period. The healthy skin demonstrated inter-animal heterogeneity over time, while the burned skin mycobiome transitioned toward a temporally stabile community with declining inter-animal variation starting at day 3 post-burn injury. Driven primarily by a significant increase in relative abundance of Candida, fungal species richness and abundance of the burned skin decreased, especially in days 7 and 11 post-burn. The network architecture of rat skin mycobiome displayed community reorganization toward increased network fragility and decreased stability compared to the healthy rat skin fungal network. This study provides the first account of the dynamic diversity observed in the rat skin mycobiome composition, structure, and network assembly associated with postcutaneous burn injury.

Bioactive peptide amphiphile nanofiber gels enhance burn wound healing

BackgroundBurns are physically debilitating and potentially fatal injuries. The standard-of-care for burn wounds is the coverage with gauze dressings designed to minimize trauma to the regenerating epidermis and dermis during dressing changes. However, deep partial- and full-thickness burns always heal slowly when standard wound care alone is performed. We have previously reported that peptide amphiphile (PA) gels, pH-induced self-assembling nanostructured fibrous scaffolds, promote cell proliferation and have great potential in regenerative medicine for rapid repair of tissues. In this study, we hypothesized that the PA gels are capable of accelerating wound healing in burn injury. MethodsArtificially generated thermally damaged fibroblasts and human umbilical vein endothelial cells were seeded onto the various PA nanofiber gels including bioactive and nonbioactive peptide sequences. Cell proliferation was assessed at different time points, and thermally damaged fibroblasts and HUVECs manifested increased proliferation with time when cultured with various PA gels. To determine in vivo effects, burn wounds of rats were treated with the bioactive Arg-Gly-Asp-Ser (RGDS)-modified gel that showed greater cell proliferation in vitro. The wound closure was observed, and skin samples were harvested for histologic evaluation. ResultsCell proliferation using the RGDS-PA gel was significantly higher than that observed in other gels. The RGDS-PA gel significantly enhanced re-epithelialization during the burn wound healing process between days 7 and 28. Application of PA gels accelerates the recovery of deep partial-thickness burn wounds by stimulation of fibroblasts and the creation of an environment conducive to epithelial cell proliferation and wound closure. ConclusionsThis biomaterial represents a new therapeutic strategy to overcome current clinical challenges in the treatment of injuries resulting from burns.

34 Direct Comparison of Different Porcine Thermal Injury Models - Is it Apples to Apples?

A vast array of animal models are used in burn injury research, however the porcine model is the most homologous to human skin. The abundance of differing models in the literature and the lack of details regarding exact procedures makes comparison of research between investigators challenging and ultimately impacts translation to humans. We aimed to compare three well-established porcine thermal injury models from distinct research programs to highlight this often unrecognized barrier to progress in the field of burn injury. Investigators were identified based on recent and robust publications containing porcine burn injury models. Investigators were asked to submit paraffin embedded tissue samples from deep partial thickness thermal injuries obtained on the day of injury. Protocol details including animal characteristics, thermal injury methods, and timing of sample collection were collected directly from individual investigators to allow for precise methodologic comparison across groups. All tissue sections were stained at one institution using Hematoxylin and Eosin (H&E) or Gomori Trichrome. The sections were reviewed in a blinded fashion by three independent labs using a standardized scoring sheet for H&E sections that used cellular and collagen changes to define injury. Duroc and Yorkshire pig breed models were compared. Temperatures ranged from 80–200 degrees Celcius, and contact time from 15–20 seconds. All groups used unique in-house manufactured metal thermal injury devices with pressure and temperature control. H&E scoring revealed two of the three models produced injury limited to the upper third of the skin, while one model produced injury into the lower third of the skin. Trichrome stain revealed collagen denaturation in only one of the three models. The depth of injury varied across the three highly accepted models despite each individual lab defining the injury as a deep partial thickness burn. Future studies are necessary to identify the model that most accurately reproduces injury in human skin to facilitate translation of thermal injury modeling in humans. A standardized model yielding a defined burn depth is critical for advancement of translational burn research that adds to the body of knowledge required to diagnose injury and develop novel therapeutics.

Outcomes of the Use of Hyaluronic Acid-Based Wound Dressings for the Treatment of Partial-Thickness Facial Burns.

The purpose of this study was to assess clinical, functional and cosmetic outcomes of the use of hyaluronic acid-based wound dressings for partial-thickness facial burns. Patients with partial-thickness facial burns hospitalized at the Burn Center between April 2014 and April 2017 were evaluated. Data pertaining to demographic characteristics, etiology, and degree of burn and percentage of burn to TBSA were collected. Pain, infection rates, reapplication rates, length of hospital stay, duration of healing, and presence of scar formation were analyzed. Median percentage of burn to TBSA was 15% (interquartile range [IQR]: 9-20). Fifteen patients had only facial burns, while 39 patients had burns on other parts of the body in addition to the face. Nine patients had deep partial-thickness burns, while 45 had superficial partial-thickness burns. Median length of hospital stay was 7 days (IQR: 3-15) for the entire study population and 4 days (IQR: 2-7.5) for patients who had only facial burns. Median healing time was 9 days (IQR: 7-12). Fifty-one (94%) patients had a Vancouver Scar Scale score of zero at 6 months. Use of hyaluronic acid-based wound dressings for facial burns is an effective and safe option.

Clinical characteristics and treatment of diabetic patients with superficial partial-thickness burn on feet

Objective: To analyze the characteristics and treatment of diabetic patients with superficial partial-thickness burn on feet. Methods: Eighty-three patients with superficial partial-thickness burn on 119 feet were hospitalized in our unit from January 2011 to December 2017. The medical records of the patients with 46 men and 37 women, aged 60±11 were retrospectively analyzed. The patients were divided into diabetes group and non-diabetes group according to whether they had diabetes or not, with 41 patients (60 burn feet) in diabetes group and 42 patients (59 burn feet) in non-diabetes group. Patients in diabetes group and non-diabetes group were given systemic treatment and wound dressing change. Thirty-seven diabetic patients whose wounds deepened to deep partial-thickness were divided into eschar shaving group and non-eschar shaving group according to patients' willingness and the treatment, with 14 patients in eschar shaving group and 23 patients in non-eschar shaving group. Patients in eschar shaving group were given eschar shaving operation at early stage, and patients in non-eschar shaving group were given wound dressing change. The length of hospital stay, hospitalization treatment expenses, pulse of arteria dorsal pedis and posterior tibial artery immediately after admission, deepening of wounds on feet during hospital stay, and rates of wound healing on feet of patients in diabetes group and non-diabetes group were observed and calculated. Pulses of arteria dorsal pedis and posterior tibial artery immediately after admission, deepening of wounds on feet during hospital stay, positive rates of bacteria and fungus in wounds on feet, and rates of wound healing on feet of patients in eschar shaving group and non-eschar shaving group were observed and calculated. Data were processed with chi-square test, t test, Fisher's exact propability method, and Mann-Whitney U test. Results: The length of hospital stay of patients in diabetes group was (29±20) d, which was significantly longer than that of patients in non-diabetes group [(19±13) d, t=2.730, P<0.01]. The hospitalization treatment expense of patients in diabetes group was (46 988±41 322) yuan, which was significantly more than that of patients in non-diabetes group [(29 106±24 813) yuan, t=2.396, P<0.05]. The pulses of arteria dorsal pedis and posterior tibial artery of patients in diabetes group were significantly weaker than those of patients in non-diabetes group (Z=3.278, 2.194, P<0.05 or P<0.01). The percentages of wounds on feet of patients in diabetes group deepening to deep partial-thickness burn, full-thickness skin defect with bone and tendon exposure were respectively 88.3% (53/60) and 23.3% (14/60), which were significantly higher than those of patients in non-diabetes group [47.5% (28/59) and 1.7% (1/59), χ(2)=22.867, 12.644, P<0.01]. Rate of wound healing on feet of patients in diabetes group was 78.3% (47/60), which was significantly lower than 100.0% (59/59) of patients in non-diabetes group ( χ(2)=14.351, P<0.01). There were respectively 21 and 32 feet in patients of eschar shaving group and non-eschar shaving group. There were no significantly statistical differences in pulses of arteria dorsal pedis and posterior tibial artery of patients between eschar shaving group and non-eschar shaving group (Z=0, 0.453, P>0.05). The percentage of wounds on feet of patients in non-eschar shaving group deepening to full-thickness skin defect with bone and tendon exposure was 43.8% (14/32), which was significantly higher than 0 of patients in eschar shaving group ( χ(2)=12.486, P<0.01). Positive rates of bacteria and fungus in wounds on feet of patients in eschar shaving group was significantly lower than that of patients in non-eschar shaving group (χ(2)=4.386, P<0.05 ). Rate of wound healing on feet of patients in non-eschar shaving group was 59.4% (19/32), which was significantly lower than that of patients in eschar shaving group [100.0% (21/21), P<0.01]. Conclusions: Diabetes patients with superficial partial-thickness burn wounds on feet has long length of hospital stay, high hospitalization treatment expenses. Wounds of the patients are easy to deepen, with low wound healing rate. Eschar shaving at early stage when the wounds deepened to deep partial-thickness burn is a good way to increase wound healing rate and prevent further deepening of wounds.

Experimental study on adipose derived stem cells combined with chitosan chloride hydrogel for treating deep partial thickness scald in rats

To prepare adipose-derived stem cells (ADSCs) and chitosan chloride (CSCl) gel complex to study the biocompatibility and the feasibility of repairing the wounds of deep partial thickness scald in rats. ADSCs were prepared by enzymogen digestion and differential adherence method from the subcutaneous adipose tissue of SPF grade 6-week-old male Sprague Dawley (SD) rats. Temperature sensitive CSCl gel was prepared by mixing CSCl, β glycerol phosphate, and hydroxyethyl cellulose in 8∶2∶2.5 ratio. The proliferation of ADSCs was measured by cell counting kit 8 (CCK-8) assay and the survival of ADSCs was detected by the Live/Dead flurescent staining in vitro. A deep partial thickness burn animal model was made on the back of 72 SPF grade 6-week-old male SD rats by boiled water contact method and randomly divided into 3 groups ( n=24). Group A was blank control group, group B was CSCl hydrogel group, group C was ADSCs/CSCl gel group. The wound closure rate at 3, 7, 14, 21 days was observed after operation. The number of inflammatory cells at 7 days and epidermal thickness at 21 days were observed by HE staining after operation. The angiogenesis at 7 days was evaluated by immunohistochemistry staining with CD31 expression. CSCl had a temperature sensitivity, at 4℃, the temperature-responsive hydrogel was liquid and became solid at 37℃. The CCK-8 assay and Live/Dead flurescent staining confirmed that ADSCs could grow and proliferate in the ADSCs/CSCl hydrogel complex. General observation showed the wound closure ratio in group C was superior to groups A and B after operation ( P<0.05). HE staining showed that at 7 days after operation, the wound healing of the three groups entered fibrous proliferation stage. Collagen deposition and inflammatory cell infiltration were observed in the dermis of each group. The proportion of inflammatory cells in group C was significantly lower than that in groups A and B, and in group B than in group A ( P<0.01). At 21 days after operation, the fibrous connective tissues of neoepithelium and dermis in groups B and C were arranged neatly, and fibroblasts and neocapillaries could be seen. In group A, neoepidermis could also be seen, but the fibrous connective tissues in dermis were arranged disorderly and sporadic capillaries could be seen. The thickness of neonatal epidermis in group C was significantly larger than that in groups A and B, and in group B than in group A ( P<0.01). CD31 immunohistochemistry staining showed that the neovascularization could be seen in all groups. The number of neovascularization in group C was significantly higher than that in groups A and B, and in group B than in group A ( P<0.05). The ADSCs/CSCl hydrogel complex has a good biocompatibility and possessed positive effects on promoting the deep partial thickness scald wound repairing in rats.

A dual deformable liposomal ointment functionalized with retinoic acid and epidermal growth factor for enhanced burn wound healing therapy.

An ointment containing retinoic acid deformable liposomes (TRA DLs) and epidermal growth factor cationic deformable liposomes (EGF CDLs) was prepared for the treatment of deep partial-thickness burns. The characterization tests confirmed both liposomes featured small particle sizes, high drug entrapment efficiencies and sustained drug release behavior. Compared with the free drug, TRA DLs and EGF CDLs exhibited superior skin permeation and remarkably increased drug deposition by 2.9 and 18.8 folds, respectively. Results on HaCaT cells indicated the combined application of two liposomes exerted a synergistic effect and prominently promoted cell proliferation and migration. Application of the dual liposomal ointment on a deep partial-thickness burn model stimulated wound closure (p < 0.001), promoted skin appendage formation and increased collagen production, thus improving healing quality. Finally, it was demonstrated that TRA significantly up-regulated the expression of EGFR and HB-EGF to enhance the therapeutic effect of EGF. Therefore, the dual liposomal ointment is a promising topical therapeutic for burn treatment.

Discordance between histologic and visual assessment of tissue viability in excised burn wound tissue

The regenerative capacity of burn wounds, and the need for surgical intervention, depends on wound depth. Clinical visual assessment is considered the gold standard for burn depth assessment but it remains a subjective and inaccurate method for tissue evaluation. The purpose of this study was to compare visual assessment with microscopic and molecular techniques for human burn depth determination, and illustrate differences in the evaluation of tissue for potential regenerative capacity. Using intraoperative visual assessment, patients were identified as having deep partial thickness or full thickness burn wounds. Tangential excisions of burn tissue were processed with hematoxylin and eosin to visualize tissue morphology, lactate dehydrogenase assay to ascertain cellular viability, and Keratin-15 and Ki67 to identify epidermal progenitor cells and proliferative capacity, respectively. RNA from deep partial and full thickness burn tissue as well as normal tissue controls were submitted for RNA sequencing. Lactate dehydrogenase, Keratin-15, and Ki67 were found throughout the excised burn wound tissue in both deep partial thickness burn tissues and in the second tangential excision of full thickness burn tissues. RNA sequencing demonstrated regenerative capacity in both deep partial and full thickness burn tissue, however a greater capacity for regeneration was present in deep partial thickness compared with full thickness burn tissues. In this study, we highlight the discordance that exists between the intraoperative clinical identification of burn injury depth, and microscopic and molecular determination of viability and regenerative capacity. Current methods utilizing visual assessment for depth of injury are imprecise, and can lead to removal of viable tissue. Additionally, hematoxylin and eosin microscopic analysis should not be used as the sole method in research or clinical determination of depth, as there are no differences in staining between viable and nonviable tissue.

Autophagy promotes angiogenesis via AMPK/Akt/mTOR signaling during the recovery of heat-denatured endothelial cells

Our previous study demonstrated that angiogenesis increased during the recovery of heat-denatured endothelial cells. However, the mechanism is still unclear. This study aimed to investigate the relation of autophagy and angiogenesis during the recovery of heat-denatured endothelial cells. A rat deep partial-thickness burn model and heat-denatured human umbilical vein endothelial cells (HUVECs) model (52 °C for 35 s) were used. Autophagy increased significantly in the dermis and HUVECs in a time-dependent manner after heat denaturation and recovery for 2–5 days. Rapamycin-mediated autophagy enhanced the pro-angiogenic effect, evidenced by increased proliferation and migration of HUVECs, and formation of tube-like structures. Autophagy inhibition by 3-Methyladenine (3-MA) abolished the angiogenesis in heat-denatured HUVECs after recovery for 3–5 days. Moreover, heat denaturation augmented the phosphorylation of AMP-activated protein kinase (AMPK) but reduced the phosphorylation of Akt and mTOR in HUVECs. Furthermore, autophagy inhibition by antioxidant NAC, compound C or AMPK siRNA impaired cell proliferation, migration and tube formation heat-denatured HUVECs. At last, the in vivo experiments also showed that inhibition of autophagy by bafilomycin A1 could suppress angiogenesis and recovery of heat-denatured dermis.Taken together, we firstly revealed that autophagy promotes angiogenesis via AMPK/Akt/mTOR signaling during the recovery of heat-denatured endothelial cells and may provide a potential therapeutic target for the recovery of heat-denatured dermis.

On-Demand Dissolvable Self-Healing Hydrogel Based on Carboxymethyl Chitosan and Cellulose Nanocrystal for Deep Partial Thickness Burn Wound Healing.

Deep partial thickness burn wounds present big challenges due to the long healing time, large size and irregular shape, pain and reinjury at wound dressing changes, as well as scarring. The clinically effective therapy to alleviate pain at wound dressing changes, and the scar left on the skin after the healing of wound is still unavailable. To combat this, we develop a nanocomposite self-healing hydrogel that can be injected into irregular and deep burn wound beds and subsequently rapidly self-heal to reform into an integrated piece of hydrogel that thoroughly fills the wound area and protects the wound site from external environment, finally being painlessly removed by on-demand dissolving using amino acid solution at wound dressing changes, which accelerates deep partial thickness burn wound healing and prevents scarring. The hydrogel is made out of naturally occurring polymers, namely, water-soluble carboxymethyl chitosan (CMC) and rigid rod-like dialdehyde-modified cellulose nanocrystal (DACNC). They are cross-linked by dynamic Schiff-base linkages between amines from CMC and aldehydes from DACNC. The large aspect ratio and specific surface area of DACNC raise massive active junctions within the hydrogel, which can be readily broken and reformed, allowing hydrogel to rapidly self-heal. Moreover, DACNC serves as nanoreinforcing fillers to improve the hydrogel strength, which also restricts the "soft" CMC chains' motion when soaked in aqueous system, endowing high fluid uptake capacity (350%) to hydrogel while maintaining integrity. Cytotoxicity assay and three-dimensional cell culture demonstrate excellent biocompatibility of the hydrogel and capacity as extracellular matrix to support cell growth. This work opens a novel pathway to fabricate on-demand dissolvable self-healing hydrogels to speed deep partial thickness burn wound healing and eliminate pain at wound dressing changes and prevent scar formation.

Preparation of hydroxylated lecithin complexed iodine/carboxymethyl chitosan/sodium alginate composite membrane by microwave drying and its applications in infected burn wound treatment

Improving the antibacterial properties of membrane wound dressings of natural polymers is crucial. Iodine is an important safe inorganic antibacterial agent, but was confined in the composition with polymer membranes due to the challenges of homogeneity and stability during drying. In the present work, iodine was complexed with hydroxylated lecithin (HL) to improve its stability and complexing efficiency for the composition with carboxymethly chitosan/sodium alginate. With the aid of microwave drying, hydroxylated lecithin complexed iodine/carboxymethly chitosan/sodium alginate (HLI/CMCS/SA) composite membranes with homogeneously distributions of HLI, high contents of activated iodine, good mechanical and swelling properties, proper water vapor permeability, pH controllable iodine release and excellent antibacterial properties were prepared. The composite membranes exhibited high repairing efficiencies for the infection of a rat model of the seawater immersed wound infection of deep partial-thickness burns. This novel antibacterial composite membrane can be potentially used as a high performance wound dressing for treating and repairing open trauma infections.

Effects of minimally invasive tangential excision in treating deep partial-thickness burn wounds on trunk and limbs in pediatric patients in the early stage post burn

Objective: To observe the effects of minimally invasive tangential excision in treating deep partial-thickness burn wounds on trunk and limbs in pediatric patients in the early stage post burn. Methods: Clinical data of 40 children with deep partial-thickness burn wounds on trunk and limbs, admitted to our burn ward from January 2016 to June 2017, conforming to the study criteria, were retrospectively analyzed. They were divided into conventional treatment group (CT, n=19) and minimally invasive tangential excision group (MITE, n=21) according to the different treatments. The patients in group CT were treated with eschar-reserving therapy firstly. When tangential excision was performed, the roller knife was used, and no necrotic tissue left on the wound bed was considered the proper depth of excision. Razor-thickness skin grafting was performed to cover the wound when adipose tissue exposed markedly after tangential excision. Dressing change was performed within 48 h after the operation and repeated every 2 days. Unhealed wounds were covered by razor-thickness skin grafting. The patients in group MITE were treated with tangential excision in the early stage post burn. The tangential excision was operated with electric dermatome, and the thickness was set at 0.1 mm to excise the surface of eschar until the sporadic punctate hemorrhage on wound surface was observed and some necrotic tissue was left on the wound bed. Porcine acellular dermal matrix was applied after tangential excision. The first dressing change was often performed about 1 week after the operation. Razor-thickness skin grafting was performed to cover the unhealed wounds. The length of wound healing, high fever, antibiotic usage, and hospital stay, times of later operation, and hospitalization expenses of patients in the 2 groups were recorded. The excisional eschar and wound bed tissue of patients in group MITE were harvested for pathological observation. Data were processed with t test and Fisher's exact probability test. Results: (1) There were no statistically significant differences in length of high fever and length of hospital stay and hospitalization expenses between patients in the 2 groups (t=-1.67, -1.93, 0.31, P>0.05). The lengths of wound healing [(24.8±2.5) d] and antibiotic usage [(4.4±0.7) d] of patients in group MITE were significantly shorter than those in group CT [(33.3±2.5) and (7.0±0.7) d, t=-2.44, -2.44, P<0.05], and times of later operation of patients in group MITE [(0.29±0.14) times] were significantly less than those in group CT [(0.79±0.21) times, t=-2.03, P<0.05]. (2) The thickness of the excisional eschar of patients in group MITE was about 150 μm. The eschar has epidermis and upper dermis. Some necrotic tissue was left on the wound bed. Conclusions: The treatment for pediatric deep partial-thickness burn wounds on trunk and limbs with minimally invasive tangential excision using electric dermatome in the early stage post burn can accelerate wound healing, shorten length of antibiotic usage, and reduce times of later operations.

Epidemiological characteristics and factors affecting length of hospital stay for children and adults with burns in Zunyi, China: a retrospective study.

ObjectiveBurn wounds are a global public health problem, and a large number of casualties are caused by burns each year. In this study, we explored the epidemiological characteristics associated with burns and the factors affecting the length of hospital stay (LOS) in children and adults with burn wounds.MethodsRecords of patients with burns in the Affiliated Hospital of Zunyi Medical University from January 1, 2014 to August 31, 2016 were retrieved. Information on demographic characteristics, mechanism of burns, first treatment received, clinical details of burns, and LOS were extracted from hospital medical records.ResultsA total of 465 children and 327 adults with burns were identified over about 2.5 years. The ratio of male to female children with burn wounds was 1.6 and 2.3 in adults. The epidemiological characteristics of burns, including gender, season, location, etiology, degree and site, differed between children and adults. There were differences in external remedies used (e.g., traditional Chinese medicine powder) and wound protection (towels covering wounds) between children and adults, but few patients had both protected wounds and did not use external remedies. LOS was reduced with age (hazard ratio [HR] = 0.993) and skin grafting (HR = 0.339). LOS increased with the male gender (HR = 1.234), deep partial thickness burns (HR = 3.128), and full-thickness burns (HR = 1.791). LOS was increased when total body surface area (TBSA) of burns reached from 10% to 29% (HR = 3.978), when TBSA was greater than 30% (HR = 1.787), and heat vs. non-heat etiologies (HR = 1.497).ConclusionOur findings for the epidemiological characteristics of burns in children and adults in Zunyi will help with a targeted awareness campaign and improve knowledge of first-aid and wound treatment.

Current challenges in the treatment of paediatric burn patients: a retrospective experience at a Viennese burn unit

Burn trauma in paediatric patients continues to be highly relevant socio-economically since the number of inpatients treated per year has not declined over the past few decades. The treatment of paediatric burn victims places high demands on medical staff and the use of wound dressings and surgical techniques. This study aimed to give a current overview of the inpatient management and treatment methods for paediatric burn patients at a specialised burn centre in Vienna. All children and adolescents who were treated at the children's ward of the Division of Plastic and Reconstructive Surgery at the Medical University of Vienna between 2012 and 2016 due to a recent burn trauma were retrospectively analysed. 115patients were treated due to a recent burn trauma. Median age was 2 years (0-18). Scalds accounted for 74 % of traumas. Median affected body surface area was 5 % (1-40 %). Conservative treatment of superficial partial-thickness wounds (62 %) was performed with MepilexAg in 98 % of cases and required a median healing time of 11 days (4-34). 38 % (n = 44) of patients had deep partial-thickness or full-thickness burns . The use of Suprathel after tangential excision of the burn eschar in more superficial deep partial-thickness burns led to satisfying healing times. The use of modern dressings in the conservative treatment of superficial partial-thickness burns allows for atraumatic dressing changes and fast recoveries. The use of Suprathel in more superficial deep partial-thickness burns is a reliable and safe alternative to autologous skin grafting. Scar prophylaxis and regular follow-up examinations are crucial to prevent secondary morbidity due to scar contractures. It is important to raise awareness among parents in order to decrease the number of paediatric burn patients in the future.

Glucocorticoids suppress fibroblast apoptosis in an in vitro thermal injury model

The wounds of full- and deep partial-thickness burns result in hypertrophic scars and lead to skin contracture more severely than those of superficial partial-thickness burns. Therefore, preventing burn progression may help improve the aesthetic and functional outcomes after healing. Although a number of studies have focused on elucidating the underlying mechanisms of and preventing burn wound progression, it is still difficult to rescue burned dermis unless early tangential excision is performed. To investigate the underlying mechanisms of and prevent cell death of heat-injured fibroblasts, we developed an in vitro experimental model of heat-injured fibroblasts. We confirmed that heating at 55°C for 30s caused fibroblast necrosis immediately after heating, whereas heating at 46°C for 30s induced apoptosis 24h after heating. We also found that the supplementation of 100ng/ml betamethasone to the culture medium after heating decreased the number of apoptotic cells and increased that of live cells. Our studies suggest that glucocorticoids suppress apoptosis of heat-injured fibroblasts and may be useful for preventing burn wound progression.

Development of Pseudomonas aeruginosa Biofilms in Partial-Thickness Burn Wounds Using a Sprague-Dawley Rat Model.

We used a modified Walker–Mason scald burn rat model to demonstrate that Pseudomonas aeruginosa, a common opportunistic pathogen in the burn ward and notable biofilm former, establishes biofilms within deep partial-thickness burn wounds in rats.Deep partial-thickness burn wounds, ~10% of the TBSA, were created in anesthetized male Sprague-Dawley rats (350–450 g; n = 84). Immediately post-burn, 100 µl of P. aeruginosa in phosphate-buffered saline at 1 × 103, 1 × 104, or 1 × 105 cells/wound was spread over the burn surface . At 1, 3, 7, and 11 days post-burn, animals were euthanized and blood and tissue were collected for complete blood counts, colony-forming unit (CFU) counts, biofilm gene expression, histology, scanning electron microscopy (SEM), and myeloperoxidase activity in the burn eschar. P. aeruginosa developed robust biofilm wound infections, plateauing at ~1 × 109 CFU/g burn tissue within 7 days regardless of inoculum size. Expression of Pseudomonas alginate genes and other virulence factors in the infected wound indicated formation of mature P. aeruginosa biofilm within the burn eschar. Compared to un-inoculated wounds, P. aeruginosa infection caused both local and systemic immune responses demonstrated by changes in systemic neutrophil counts, histology, and myeloperoxidase activity within the burn wound. Additionally, SEM showed P. aeruginosa enmeshed within an extracellular matrix on the burn surface as well as penetrating 500–600 µm deep into the eschar. P. aeruginosa establishes biofilms within deep partial-thickness burn wounds and invades deep into the burned tissue. This new in vivo biofilm infection model is valuable for testing novel anti-biofilm agents to advance burn care.