深Ⅱ度烧伤创面伤后24小时内削痂的临床观察

目的　探讨深Ⅱ度烧伤患者伤后 2 4h内创面行削痂术的安全性和临床疗效。　方法12例有削痂手术指征并在伤后 2 4h内行削痂术的深Ⅱ度烧伤患者为A组 ;14例削痂条件相似并按常规在伤后 4～ 6d行削痂术的深Ⅱ度烧伤患者为B组。比较两组休克期补液量、休克征象发生率、回吸收期的生命体征、尿量及愈合时间。　结果　两组患者在休克期补液量、休克征象发生率方面差异均无显著性意义 (P >0 .0 5 ) ;A组休克期尿量明显增多 ,回吸收期的体温、心率与B组明显不同(P <0 .0 5～ 0 .0 1) ;A组创面平均愈合时间较B组短 (P <0 .0 1)。　结论　深Ⅱ度烧伤创面于伤后2 4h内削痂是安全的 ,并能缩短创面愈合时间。     

Antecedent thermal injury worsens split-thickness skin graft quality: A clinically relevant porcine model of full-thickness burn,excision and grafting

Current standard of care for full-thickness burn is excision followed by autologous split-thickness skin graft placement. Skin grafts are also frequently used to cover surgical wounds not amenable to linear closure. While all grafts have potential to contract, clinical observation suggests that antecedent thermal injury worsens contraction and impairs functional and aesthetic outcomes. This study evaluates the impact of antecedent full-thickness burn on split-thickness skin graft scar outcomes and the potential mediating factors. Full-thickness contact burns (100 °C, 30 s) were created on the backs of anesthetized female Yorkshire Pigs. After seven days, burn eschar was tangentially excised and covered with 12/1000th inch (300 μm) split-thickness skin graft. For comparison, unburned wounds were created by sharp excision to fat before graft application. From 7 to 120 days post-grafting, planimetric measurements, digital imaging and biopsies for histology, immunohistochemistry and gene expression were obtained. At 120 days post-grafting, the Observer Scar Assessment Scale, colorimetry, contour analysis and optical graft height assessments were performed. Twenty-nine porcine wounds were analyzed. All measured metrics of clinical skin quality were significantly worse (p < 0.05) in burn injured wounds. Histological analysis supported objective clinical findings with marked scar-like collagen proliferation within the dermis, increased vascular density, and prolonged and increased cellular infiltration. Observed differences in contracture also correlated with earlier and more prominent myofibroblast differentiation as demonstrated by α-SMA staining. Antecedent thermal injury worsens split-thickness skin graft quality, likely by multiple mechanisms including burn-related inflammation, microscopically inadequate excision, and dysregulation of tissue remodeling. A valid, reliable, clinically relevant model of full-thickness burn, excision and skin replacement therapy has been demonstrated. Future research to enhance quality of skin replacement therapies should be directed toward modulation of inflammation and assessments for complete excision.     

早期削痂全厚皮片移植治疗小儿手部深度烧伤

自1990年以来,我们对18例21只小儿手部深度烧伤行早期削痂、全厚皮片移植,术后外形及功能均较满意,取得良好效果。该手术适用于生命体征较平稳、供皮区充裕的中小面积烧伤的患儿,且手术方法简便,可有效地预防小儿手部深度烧伤后的畸形。     

Burn healing is dependent on burn site: a quantitative analysis from a porcine burn model

This retrospective review examines healing in different sites on a porcine burn model; 24 pairs of burns on 18 pigs from other animal trials were selected for analysis. Each pair of burns was located on the either the cranial or the caudal part of the thoracic ribs region, on the same side of the animal. The burns were 40-50 cm(2) in size and of uniform deep-dermal partial thickness. Caudal burns healed significantly better than cranial burns, demonstrated by earlier closure of wounds, less scar formation and better cosmesis. To our knowledge, this is the first detailed study reporting that burn healing is affected by location on a porcine burn model. We recommend that similar symmetrical burns should be used for future comparative assessments of burn healing.     

A retrospective review of burn dressings on a porcine burn model

This is a study to compare wound healing among three types of dressings on a porcine model with deep-dermal-partial-thickness burns. The burns in this study were from eight animal trials conducted in the past for other purposes and only burns with a uniform pale appearance that had served as controls in original experiments were selected. In total, there were 57 burns in 33 pigs, using one of following three dressings: Acticoat (Silver) (3 trials), Jelonet (Gauze) (3 trials), and Solosite Gel/Jelonet (Gel/Gauze) (2 trials). The wound healing assessments included wound re-epithelialisation during a 6-week period, clinical and histological scar assessments at week 6 after burn. Of all wound healing/scar assessments, only re-epithelialisation showed statistical difference between dressings. Earlier re-epithelialisation was observed in Gel/Gauze dressings compared to Silver and/or Gauze dressings. However, this study revealed huge variation in wound healing outcome between 3 trials within both Silver and/or Gauze dressings, supported by significant differences on re-epithelialisation, clinical and histological scar measurements. In addition, it was found that larger animals healed better than smaller ones, based on weights from 21 pigs. Of all dressings, Silver delivers the best protection for wound colonization/infection. Wound colonization/infection was found to confine wound healing and lead to thinner RND in scars. From this study, we cannot find enough evidence to suggest the beneficial effect of one dressing(s) over others on burn wound healing outcome on a porcine model with small deep-dermal-partial-thickness burns with a relative small sample size.     

烧伤后24小时内削痂对深Ⅱ度创面局部炎症反应的影响

目的探讨烧伤后24h内行削痂手术对深Ⅱ度创面局部炎症反应以及组织损害的影响。方法选择12例烧伤患者,伤后24h内对深Ⅱ度创面行削痂手术,将患者同一创面分为3个标本采集区,即手术前、手术后和未手术区。手术前标本取自削痂术前创面,手术后和未手术区创面标本于伤后5—7d获取。采用组织培养和比色法测定创面组织释放白细胞介素(IL)8、髓过氧化物酶(MPO)和丙二醛(MDA)的水平,通过HE和Masson染色对创面组织坏死程度进行形态学观察。结果削痂手术后,患者创面组织局部释放IL8、MPO、MDA的水平分别为(6.83±1.85)μg/L、(4.07±0.87)U/g、(8.94±5.66)μmol/g,与未手术创面比较明显降低(P<0.01)。形态学观察显示,手术前创面有凝固性坏死灶;未手术创面炎症反应明显,坏死组织范围扩大;削痂手术后创面局部的炎症反应得到改善,未见坏死组织范围扩大。结论伤后24h内行削痂手术,可以改善深Ⅱ度烧伤创面局部的炎症反应,防止创面进行性加深,有利于创面及早愈合。     

Development of a long-term ovine model of cutaneous burn and smoke inhalation injury and the effects of early excision and skin autografting

Smoke inhalation injury frequently increases the risk of pneumonia and mortality in burn patients. The pathophysiology of acute lung injury secondary to burn and smoke inhalation is well studied, but long-term pulmonary function, especially the process of lung tissue healing following burn and smoke inhalation, has not been fully investigated. By contrast, early burn excision has become the standard of care in the management of major burn injury. While many clinical studies and small-animal experiments support the concept of early burn wound excision, and show improved survival and infectious outcomes, we have developed a new chronic ovine model of burn and smoke inhalation injury with early excision and skin grafting that can be used to investigate lung pathophysiology over a period of 3 weeks.     

A randomized,double-blind,phase I clinical trial of fetal cell-based skin substitutes on healing of donor sites in burn patients

BackgroundDue to limited graft donor sites in extensive burns, re-harvesting of a single donor area is very common. Given the importance of fetal fibroblasts in accelerating fetal wound healing, fetal cell-based skin substitutes have emerged as a novel therapeutic modality for regenerating damaged skin. In this trial, we aimed to evaluate the safety, feasibility and potential efficacy of application of amniotic membranes seeded with fetal fibroblasts for accelerating donor sites healing in burn patients.MethodsIn this randomized, double-blind, phase I clinical trial, 10 patients with total burn surface area of 10–55% were enrolled. Three equal parts (10 × 10 cm) were selected in donor site of each patient and covered by Vaseline gauze (control group), amniotic membrane (AM group), or amniotic membrane seeded with fetal fibroblasts (AM-F group). Adverse events, pain intensity scores, and wound sizes were recorded on days 4, 8, 11, 14, and 20 post-treatment. Also, histological assessments were done on days 0 and 14 after the surgery.ResultsAll patients underwent surgery, and no adverse events occurred during the procedure and follow-up period. Significantly lower pain intensity and higher healing rates were observed in AM-F and AM groups compared to the control group. Moreover, mean complete re-epithelializatin in AM-F and AM groups were 10.1 ± 2.4 and 11.3 ± 2.9 days, showing that the healing process was significantly accelerated compared to the control group with mean closure time of 14.8 ± 1.6 days. Histological assessment showed lower inflammatory cells infiltration in AM-F and AM groups compared to control group.ConclusionsThis study indicated the safety of transplantation of amniotic membrane seeded with fetal fibroblasts for treatment of donor sites in burn patients; however, preliminary assessments showed no benefits for this therapeutic modality over amniotic membrane alone. Thus, to draw accurate conclusions, further trials in larger populations should be conducted.Level of Evidence: This study is assigned as level I.     

Ⅱ度烧伤病人皮肤角朊细胞ICAM-1的表达

目的探讨Ⅱ度烧伤创面愈合过程中角朊细胞间粘附分子-1(ICAM-1)的表达及其意义。方法应用免疫组织化学染色技术,对烧伤后不同时间Ⅱ度烧伤皮肤组织角朊细胞 ICAM-1的表达进行动态观察。8例健康人皮肤,6例烧伤病人正常皮肤及8例Ⅱ度烧伤愈合后增生性瘢痕组织为对照组。结果健康人正常皮肤基底层细胞 ICAM-1可低表达,烧伤病人正常皮肤基底层细胞ICAM-1可表达增强。Ⅱ度创面基底层细胞伤后1周内 ICAM-1表达轻度增高,2周内明显增强,2～4周稳定高表达,ICAM-1呈极性分布,新生上皮多层角朊细胞 ICAM-1表达显著增强,ICAM-1阳性细胞呈长柱状排列。结论Ⅱ度烧伤皮肤角朊细胞 ICAM-1表达增强可能与创基炎性细胞浸润相关,具有诱导角朊细胞增殖、迁移,加速上皮化的作用。     

影响碱性成纤维细胞生长因子促进烧伤创面愈合因素的探讨

采用大白鼠１５％Ⅲ度烧伤模型，探讨了影响碱性成纤维细胞生长因子（ｂＦＧＦ）促进烧伤创面愈合的因素。结果发现，烧伤创面早期切痂可保持ｂＦＧＦ的活性。４０天创面愈合率达８４．０％，而未切痂组愈合率仅９，Ｏ％。肝素可增强ｂＦＧＦ促进创面肉芽组织生长、毛细血管增生、纤维母细胞增殖及细胞ＤＮＡ合成。创面感染的控制有利于保护ｂＦＧＦ的活性。伤后１周开始使用ｂＦＧＦ为适宜时期。     

Mesenchymal stem cells combined with an artificial dermal substitute improve repair in full-thickness skin wounds

Autografts represent the gold standard for the treatment of full thickness burns. Factors such as lack of suitable donor sites and poor skin quality, however, have led to the development of artificial dermal substitutes. The investigation of mechanisms leading to enhanced functionality of these skin substitutes has been attracting great attention. This study aimed to investigate the effect of autologous stem cells on the integration and vascularization of a dermal substitute in full-thickness skin wounds, in a murine model. Two cell populations were compared, whole bone marrow cells and cultivated mesenchymal stem cells, isolated from mice transgenic for the enhanced green fluorescent protein, which allowed tracking of the transplanted cells. The number of cells colonizing the dermal substitute, as well as vascular density, were higher in mice receiving total bone marrow and particularly mesenchymal stem cells, than in control animals. The effect was more pronounced in animals treated with mesenchymal stem cells, which located primarily in the wound bed, suggesting a paracrine therapeutic mechanism. These results indicate that combining mesenchymal stem cells with artificial dermal substitutes may represent an important potential modality for treating full thickness burns, even in allogeneic combinations due to the immunoregulatory property of these cells.     

应用不同类型皮瓣修复电烧伤深度创面

目的　总结采用不同类型皮瓣修复严重电烧伤患者创面的临床经验。　方法　应用游离皮瓣、轴型血管蒂岛状皮瓣、局部邻近皮瓣、肌皮瓣等修复 4 9例电烧伤患者的 6 4个创面。　结果　皮瓣完全坏死 2例 ,边缘淤血坏死 4例 ,其余皮瓣均完全成活 ,创面Ⅰ期愈合。　结论　根据电烧伤程度选择恰当的皮瓣修复创面 ,能较好地防止深部组织感染和渐进性坏死 ,是一种有效、可靠的治疗手段。     

Carbon dioxide laser ablation with immediate autografting in a full-thickness porcine burn model.

OBJECTIVE: To compare the long-term clinical and histologic outcome of immediate autografting of full-thickness burn wounds ablated with a high-power continuous-wave CO2 laser to sharply débrided wounds in a porcine model. SUMMARY BACKGROUND DATA: Continuous-wave CO2 lasers have performed poorly as tools for burn excision because the large amount of thermal damage to viable subeschar tissues precluded successful autografting. However, a new technique, in which a high-power laser is rapidly scanned over the eschar, results in eschar vaporization without significant damage to underlying viable tissues, allowing successful immediate autografting. METHODS: Full-thickness paravertebral burn wounds measuring 36 cm2 were created on 11 farm swine. Wounds were ablated to adipose tissue 48 hours later using either a surgical blade or a 150-Watt continuous-wave CO2 laser deflected by an x-y galvanometric scanner that translated the beam over the tissue surface, removing 200 microm of tissue per scan. Both sites were immediately autografted and serially evaluated clinically and histologically for 180 days. RESULTS: The laser-treated sites were nearly bloodless. The mean residual thermal damage was 0.18+/-0.05 mm. The mean graft take was 96+/-11% in manual sites and 93+/-8% in laser sites. On postoperative day 7, the thickness of granulation tissue at the graft-wound bed interface was greater in laser-debrided sites. By postoperative day 180, the manual and laser sites were histologically identical. Vancouver scar assessment revealed no differences in scarring at postoperative day 180. CONCLUSIONS: Long-term scarring, based on Vancouver scar assessments and histologic evaluation, was equivalent at 6 months in laser-ablated and sharply excised sites. Should this technology become practical, the potential clinical implications include a reduction in surgical blood loss without sacrifice of immediate engraftment rates or long-term outcome.     

Moist dressing coverage supports proliferation and migration of transplanted skin micrografts in full-thickness porcine wounds

Transplantation of skin micrografts in a 1:100 ratio regenerate the epidermis of full-thickness wounds in pigs within 14 days in a wet environment. The aim of the current study was to combine micrografts and commercially available moist dressings. We hypothesized that micrografts regenerate the epidermis when covered with a moist dressing. 5 cm × 5 cm and 10 cm × 10 cm full-thickness wounds were created on the backs of pigs. Wounds were transplanted with 0.8 mm × 0.8 mm micrografts created from a split-thickness skin graft in a 1:100 ratio. 5 cm × 5 cm wounds were treated with wound chambers, moist dressings or dry gauze (non-transplanted control group). 10 cm × 10 cm wounds were compared to non-transplanted wounds, both covered with moist dressings. Reepithelialization was assessed in biopsies from day 10, 14 and 18 post-transplantation. 5 cm × 5 cm transplanted wounds covered with moist dressings showed 69.5 ± 20.6% reepithelialization by day 14 and 90.5 ± 10.4% by day 18, similar to wounds covered with a wound chamber (63.9 ± 16.7 and 86.2 ± 11.9%, respectively). 18 days post-transplantation, 10 cm × 10 cm transplanted wounds covered with moist dressings showed 66.1 ± 10.3% reepithelialization, whereas nontransplanted wounds covered with moist dressings were 40.6 ± 6.6% reepithelialized. We conclude that micrografts combined with clinically available moist dressings regenerate the epidermis of full-thickness wounds.     

Nerve growth factor and burn wound healing: Update of molecular interactions with skin cells

Burn wound healing is a very intricate and complex process that conventionally includes three interrelated and overlapping stages of hemostasis/inflammation, proliferation and remodeling. This review aims to explore the molecular interactions of NGF with the most prominent cell types in the skin and their respective secretory products during wound healing, particularly burn wound healing. Different types of cells such as, nerve cells, endothelial cells, mast cells, macrophages, neutrophils, keratinocytes and fibroblasts all come into play through a plethora of cytokines and growth factors including nerve growth factor (NGF). NGF is a pleiotropic molecule that exerts its effects on all the aforementioned cells using two types of receptors (TrkA and p75) and affects wound healing by decreasing healing time and improving the quality of the scar. Both receptors mediate cellular proliferation, survival and apoptosis through complex signaling molecules. During the inflammatory phase, macrophages and mast cells secrete ample cytokines and growth factors, including NGF, which participate in the inflammatory reaction and induction of other cells targeting a homeostatic state. The proliferative phase follows, and NGF promotes angiogenesis through VEGF and FGF expression in endothelial cells. NGF also stimulates keratinocyte proliferation and neurite extension through the TrkA-PI3K/Akt pathway. Other molecules such as TGF-β1, IL-1β and TNF-α increase NGF expression in fibroblasts through dynamic interactions with Smads and MAPK molecules. Stimulated fibroblasts induce new collagen production to form the granulation tissue. In the remodeling phase, NGF regulates fibroblasts and induces their differentiation into myofibroblasts ultimately leading to wound contracture. In addition, NGF stimulates melanocytes and enhances hair growth and pigmentation. Such data depict the mechanisms of action of NGF implicated in the various stages of the healing process and support its applicability as a new targeted therapeutic molecule effective in burn wound healing but with some limitations.     

Wound healing at adaptation zones of skin flaps harvested from acute burned skin

Background

Early reconstruction of burn defects culminates in more successful results. The wound healing process of the burned skin affects not only the curative phase of the burned area but also result of any reconstructive procedure including the regional flaps. Thus, in this study, we have evaluated the wound healing process at the distal incisions of random-pattern skin flaps prepared from burned dorsal skin of rats.

Materials and methods

Thermal burn damage was performed with dimensions of 3 cm × 3 cm on Wistar albino rats. In group 1 (n = 12), no burn was produced and 3 cm × 3 cm caudally based, random-pattern skin flaps were elevated. In group 2 (n = 12), a 5 cm × 5 cm area of partial-thickness thermal damage was produced and after three days a 3 cm × 3 cm random-pattern skin flap was elevated as in group 1 inside the burned skin site. In group 3 (n = 12), 3 cm × 3 cm area of partial-thickness thermal damage was produced and after three days 3 cm × 3 cm random-pattern skin flap was elevated. In group 4 (n = 12), 3 cm × 3 cm area of partial-thickness thermal damage was produced and after three days a 3 cm × 3 cm random-pattern skin flap was elevated at the distal margin of the burned area. The flaps were adapted to the donor sites in all groups. The histopathological evaluation was done and hydroxyproline levels were measured.

Results

There were no significant differences between groups regarding presence of epithelialization, myofibroblast numbers, and collagen texture (p > 0.05). Neovascularization level was significantly higher in group 2 than the other groups (p < 0.05). There were no statistically significant difference among the hydroxyproline levels in all four groups (p > 0.05).

Conclusion

The preference of the incision site in a burn zone while designing a flap during the acute burn period was proposed to possess no difference in terms of wound healing in an animal model.     

Effect of silver on burn wound infection control and healing: review of the literature

Silver compounds have been exploited for their medicinal properties for centuries. At present, silver is reemerging as a viable treatment option for infections encountered in burns, open wounds, and chronic ulcers. The gold standard in topical burn treatment is silver sulfadiazine (Ag-SD), a useful antibacterial agent for burn wound treatment. Recent findings, however, indicate that the compound delays the wound-healing process and that silver may have serious cytotoxic activity on various host cells. The present review aims at examining all available evidence about effects, often contradictory, of silver on wound infection control and on wound healing trying to determine the practical therapeutic balance between antimicrobial activity and cellular toxicity. The ultimate goal remains the choice of a product with a superior profile of infection control over host cell cytotoxicity.     

血浆冷沉淀物在深度烧伤创面应用的实验及临床研究

目的　观察血浆冷沉淀物应用烧伤创面的治疗效果。方法　通过对 4 0只豚鼠烧伤模型及 4 6例临床烧伤患者创面应用血浆冷沉淀物与创面应用磺胺嘧啶银对照观察伤后创面愈合率、愈合时间。结果　应用血浆冷沉淀实验组创面愈合率、愈合时间优于应用磺胺嘧啶银对照组 ,表明血浆冷沉淀具有促进烧伤创面愈合作用。结论　血浆冷沉淀中所含的主要成分纤维连接蛋白 ,具有很强的生物活性 ,它能促进上皮细胞生长     

Comparison of the antibacterial effect of silver sulfadiazine 1%, mupirocin 2%, Acticoat and octenidine dihydrochloride in a full-thickness rat burn model contaminated with multi drug resistant Acinetobacter baumannii

In this study, our aim is to compare the efficacy of different topical antibacterial agents in a rat model contaminated with a multi drug resistant (MDR) standard Acinetobacter baumannii strain.     

A systematic review and meta-analysis of randomized trials evaluating the efficacy of autologous skin cell suspensions for re-epithelialization of acute partial thickness burn injuries and split-thickness skin graft donor sites

BackgroundThis systematic review evaluated the efficacy of autologous skin cell suspensions (ASCS) on the re-epithelialization of partial thickness burn injuries and skin graft donor site wounds.MethodsFour databases (EMBASE, Google Scholar, MEDLINE, Web of Science), grey literature and select journal hand-searching identified studies from 1975 - 2020. Randomized trials evaluating partial thickness burn management with non-cultured ASCS compared to any other intervention were included. Time to re-epithelialization (TTRE) was the primary outcome. Three independent researchers completed screening, data extraction and certainty of evidence assessment using Cochrane Risk of Bias Tool and Grading of Recommendations Assessment, Development and Evaluation.ResultsFive trials (n = 347) reported on adults (2 trials) and children (1 trial) with burn wounds, and adults with donor site wounds (2 trials). The effect of ASCS compared to control on TTRE in adult burn wounds was not estimable. TTRE was shorter in pediatric burn wounds (SMD -1.75 [95% CI: -3.45 to -0.05]) and adult donor site wounds (SMD-5.71 [95% CI: -10.61 to-0.81]) treated with ASCS. The certainty of evidence was very low.ConclusionCompared to standard care, ACSC may reduce pediatric partial thickness burn wound and adult split-thickness skin graft donor site TTRE.RegistrationPROSPERO CRD42019133171