A porcine model of full-thickness burn, excision and skin autografting

Acute burn wounds often require early excision and adequate coverage to prevent further hypothermia, protein and fluid losses, and the risk of infection. Meshed autologous skin grafts are generally regarded as the standard treatment for extensive full-thickness burns. Graft take and rate of wound healing, however, depend on several endogenous factors. This paper describes a standardized reproducible porcine model of burn and skin grafting which can be used to study the effects of topical treatments on graft take and re-epithelialization.Procedures provide a protocol for successful porcine burn wound experiments with special focus on pre-operative care, anesthesia, burn allocation, excision and grafting, postoperative treatment, dressing application, and specimen collection. Selected outcome measurements include percent area of wound closure by planimetry, wound assessment using a clinical assessment scale, and histological scoring.The use of this standardized model provides burn researchers with a valuable tool for the comparison of different topical drug treatments and dressing materials in a setting that closely mimics clinical reality.     

自体组织工程化皮肤修复全层皮肤缺损的实验研究

目的为制成含表皮细胞与成纤维细胞的双层皮肤替代物,直接用于修复全层皮肤缺损.方法选用长枫杂交仔猪10只,酶消化法获取皮肤表皮细胞与成纤维细胞,将原代培养处于对数生长期的表皮细胞、成纤维细胞分别与30%氧化异丙烯F-127 混匀成细胞悬液后,种植聚羟基乙酸(polyglycolic acid,PGA)形成细胞-生物材料复合物,用于修复自体动物背部直径4 cm全层皮肤缺损,以单纯生物材料(PGA+氧化异丙烯)充填的创面作为对照组.修复术后1,2,4,8周取材,通过组织学和基底膜特殊染色等方法对新生组织进行评价.结果第1周新生组织即出现表皮与真皮2层结构,特殊染色观察到连续的基底膜.第2周表皮与真皮均较前增厚.修复后第8周组织工程化皮肤的形态结构均与正常皮肤相似.对照组则无皮肤形成,仅见大量肉芽组织.结论应用组织工程技术,以PGA+氧化异丙烯为表皮细胞、成纤维细胞载体构建的组织工程化皮肤可修复全层皮肤缺损.     

自体组织工程化全层皮肤缺损修复实验研究

目的 为制成含表皮细胞与成纤维细胞的双层皮肤替代物，直接用于修复全层皮肤缺损。方法 选用长枫杂交仔猪10只，酶消化法获取皮肤表皮细胞与成纤维细胞，将原代培养处于对数生长期的表皮细胞、成纤维细胞分别与30％氧化异丙烯F－127混匀成细胞悬液后，种植聚羟基乙酸（polyglycolic acid,PGA)形成细胞－生物材料复合物，用于修复自体动物背部直径4cm全层皮肤缺损，以单纯生物材料（PGA＋氧化异丙烯）充填的创面作为对照组。修复术后1，2，4，8周取材，通过组织学和基底膜特殊染色等方法对新生组织进行评价。结果 第1周新生组织即出现表皮与真皮2层结构，特殊染色观察到连续的基底膜。第2周表皮与真皮均较前增厚。修复后第8周组织工程化皮肤的形态结构均与正常皮肤相似。对照组则无皮肤形成，仅见大量肉芽组织。结论 应用组织工程技术，以PGA 氧化层丙烯为表皮细胞、成纤维细胞载体构建的组织工程化皮肤可修复全层皮肤缺损。     

组织工程技术修复皮肤缺损的动物实验

目的　探索应用组织工程技术修复包括皮下组织的皮肤缺损的方法。方法　长枫杂交仔猪 2 0只 ,取腹部 2cm× 2cm全厚皮肤 ,酶消化法获取表皮细胞与成纤维细胞。经原代培养 ,将处于对数生长期的表皮细胞、成纤维细胞分别与 30 %氧化异丙烯F 1 2 7(pluronicF 1 2 7)混匀成细胞悬液后 ,种植于聚羟基乙酸 (polyglycolicacid ,PGA)形成细胞 生物材料复合物 ,用于修复自体背部直径 4cm皮肤缺损 ,以单纯生物材料 (PGA 30 %氧化异丙烯F 1 2 7)修复作为对照组。术后 1、2、4、8周取材 ,通过组织学方法评价新生组织。结果　实验组 :第 1周 ,形成含表皮与真皮两层结构的组织工程化皮肤 ;第 2周 ,表皮与真皮均较前增厚 ;第 8周 ,组织工程化皮肤的结构与正常皮肤相似 ,仅缺乏毛发、毛囊和汗腺等附属器。对照组 :则无皮肤形成 ,仅见大量肉芽组织。结论　以原代培养的表皮细胞与成纤维细胞作为种子细胞 ,PGA 30 %氧化异丙烯F 1 2 7为细胞载体的方法可修复皮肤缺损。     

Tracheal replacement with an aortic autograft.

Tracheal replacement after extensive resection remains a challenge for the thoracic surgeon. We propose an innovative solution: the use of an aortic autograft. After an experimental work on animals with aortic autografts and allografts [Martinod E, Seguin A, Pfeuty K, Fornes P, Kambouchner M, Azorin JF, Carpentier AF. Long-term evaluation of the replacement of the trachea with an autologous aortic graft. Ann Thorac Surg 2003;75(5):1572-8; Martinod E, Seguin A, Holder-Espinasse M, Kambouchner M, Duterque-Coquillaud M, Azorin JF, Carpentier AF. Tracheal regeneration following tracheal replacement with an allogenic aorta. Ann Thorac Surg 2005;79(3):942-8], we present the first human case of long tracheal replacement with an aortic autograft. In this case we replaced 7 cm of a tumoral trachea using an aortic infra-renal autograft supported by a silicone stent. The early postoperative course was uneventful. The stent was removed at three months. The patient died at six months from an acute pulmonary infection without any sign of anastomosis leakage or graft rupture. A new field of clinical study has to be investigated.     

Enhanced healing of full-thickness burn wounds using di-rhamnolipid

The aim of this study was to investigate the properties of di-rhamnolipid [alpha-L-rhamnopyranosyl-(1-2)-alpha-L-rhamnopyranosyl-3-hydroxydecanoyl-3-hydroxydecanoic acid, also referred to as di-rhamnolipid BAC-3] relating to the process of cutaneous wound healing. Di-rhamnolipid was prepared in a eucerin ointment and applied topically on full-thickness burn wounds in normal Sprague-Dawley rats covering 5% of the total body surface area. The rate of wound closure was measured over the period of 45 days. The collagen content was evaluated microscopically, by performing densitometric analysis on Verhoeff's stained histopathological slides of wound biopsies taken at the end of 45th day of di-rhamnolipid treatment. Di-rhamnolipid toxicity was assessed with the subcutaneous multi-dose study in Swiss-Webster mice. The treatment of full-thickness-burn wounds with topical 0.1% di-rhamnolipid accelerated the closure of wounds on day 21 of the treatment by 32% compared to the control (p < 0.05). On day 35, the wounds closed in all animals-treated with 0.1% di-rhamnolipid ointment while some rats in the control group had open wounds on days 35 and even 45. Histologic comparisons have shown that di-rhamnolipid significantly decreased collagen content in burn wounds (47.5%, p < 0.05) as compared to the vehicle-treated (control) wounds. Di-rhamnolipid was well-tolerated. The results of this study raise the possibility of potential efficacy of di-rhamnolipid in accelerating normal wound healing and perhaps in overcoming defects associated with healing failure in chronic wounds.     

Use of autologous tissue engineered skin to treat porcine full-thickness skin defects

Iinn irteiaceln ta uyteoagrrsa,ft sk iann dgra fatlilnoggr hafats e pvroelvpaedra tfiroonms th toebiosynthetic and tissue-engineered living skinreplacements.The production of bioengineered humantissues has led to fascinating diversity of medicalapplications,notably for permanent burn woundcoverage.1For a few decades,various skin substituteshave been introduced for extensive full-thickenss burnmanagement,and also provided new approaches forreconstructive surgery.2-7In addition,allografting ofcu…     

皮肤软组织扩张术美容修复烧伤后头皮缺损合并颅骨外露

目的：探讨应用皮肤软组织扩张术一期修复头部深度烧伤所致头皮缺损和颅骨外露的可行性和实用性。方法：1998年～2008年,我科共收治14例严重烧伤后头皮缺损合并颅骨外露的患者,其中电击伤12例,煤气中毒昏迷后颞顶部煤炉灼伤2例。头皮缺损面积4cm×6cm～8cm×16cm,颅骨外露最小3cm×2cm,最大12cm×6cm。电击伤或深度烧伤后1～6月余,创面清洁换药后,无明显创周炎,术中碘伏纱布覆盖创面并缝合固定,应用圆形和肾形皮肤软组织扩张器,置于头皮帽状腱膜下层,其切口位于预扩张皮瓣的远端,剥离范围距离创缘不小于2cm。注水扩张时间为1～5月,扩张器埋置1～3只,注水扩张总容量300～900ml,扩张额外皮肤面积为缺损面积的1.5～2倍。术中将外露坏死颅骨外板予以清除;或者在颅骨外板上钻孔,等待肉芽生长后,再行预扩张皮瓣覆盖。将扩张器取出后,将皮瓣和腔隙内形成的纤维膜切断,以利于皮瓣延伸和转移,并放置负压引流。结果：扩张部位无1例发生感染;有2例预扩张面积不够,经头皮总动员覆盖头皮缺损创面;其中1例坏死颅骨清除不彻底,形成枕部窦道,经再次手术,清除死骨并行局部皮瓣转移手术,修复枕部窦道;1例颞骨外露创面经接力扩张修复。术后头皮毛发生长如常。结论：电击伤等所致头皮缺损合并颅骨外露创面,完全可以应用软组织扩张术形成的头皮预扩张皮瓣进行一次性美容修复,无须Ⅱ期解决秃发畸形问题,较传统方法有明显优点。     

Post-burn breast resurfacing using an abdominal full-thickness skin graft.

We describe a case of delayed resurfacing of the right breast using the abdominal skin as a full-thickness graft in a 38-year-old woman who sustained a scald injury in childhood. The postoperative results are shown.     

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.     

Comparative assessment of cultured skin substitutes and native skin autograft for treatment of full-thickness burns.

OBJECTIVE: Comparison of cultured skin substitutes (CSSs) and split-thickness autograft (STAG) was performed to assess whether the requirement for autologous skin grafts may be reduced in the treatment of massive burns. SUMMARY BACKGROUND DATA: Cultured skin substitutes consisting of collagen-glycosaminoglycan substrates populated with autologous fibroblasts and keratinocytes have been demonstrated to close full-thickness skin wounds in athymic mice and to express normal skin antigens after closure of excised wounds in burn patients. METHODS: Data were collected from 17 patients between days 2 and 14 to determine incidence of exudate, incidence of regrafting, coloration, keratinization, and percentage of site covered by graft (n = 17). Outcome was evaluated on an ordinal scale (0 = worst; 10 = best) beginning at day 14, with primary analyses at 28 days (n = 10) and 1 year (n = 4) for erythema, pigmentation, epithelial blistering, surface roughness, skin suppleness, and raised scar. RESULTS: Sites treated with CSSs had increased incidence of exudate (p = 0.06) and decreased percentage of engraftment (p < 0.05) compared with STAG. Outcome parameters during the first year showed no differences in erythema, blistering, or suppleness. Pigmentation was greater, scar was less raised, but regrafting was more frequent in CSS sites than STAG. No differences in qualitative outcomes were found after 1 year, and antibodies to bovine collagen were not detected in patient sera. CONCLUSIONS: These results suggest that outcome of engrafted CSSs is not different from STAG and that increased incidence of regrafting is related to decreased percentage of initial engraftment. Increased rates of engraftment of CSSs may lead to improved outcome for closure of burn wounds, allow greater availability of materials for grafting, and reduce requirements for donor skin autograft.     

自体全厚皮片移植后表皮一黑色素单位超微结构动态变化

目的探讨自体全厚皮片移植后色素沉着的成因.方法应用超微结构细胞化学技术观察自体全厚皮片移植后表皮-黑色素单位(EpidermalMelaninUnit,EMU)的超微结构动态变化,并借助电子计算机辅助图像分析技术,对黑色素细胞及角朊细胞内的黑色素小体形态学及分布形式进行分析.结果术后48h内表皮黑色素单位处于崩解状态;术后72h后,表皮黑色素细胞(Mel-anocvte,MC)及角朊细胞(Kerationeyte,KC)功能及协同作用逐渐恢复并超过术前水平;1个月后,KC内,尤其是棘层及颗粒层KC内出现大量、呈单个分布的MS.结论EMU内KC-MC协同功能增强及从基底层到颗粒层的KC内出现大量大体积、呈单个形式分布的MS,是造成过度皮片色素沉着的直接原因.     

自体全厚皮片移植后表皮—黑色素单位超微结构动态变化

目的　探讨自体全厚皮片移植后色素沉着的成因。方法　应用超微结构细胞化学技术观察自体全厚皮片移植后表皮—黑色素单位 (EpidermalMelaninUnit,EMU)的超微结构动态变化 ,并借助电子计算机辅助图像分析技术 ,对黑色素细胞及角朊细胞内的黑色素小体形态学及分布形式进行分析。结果　术后 48h内表皮黑色素单位处于崩解状态 ;术后 72h后 ,表皮黑色素细胞 (Mel anocyte ,MC)及角朊细胞 (Kerationcyte,KC)功能及协同作用逐渐恢复并超过术前水平 ;1个月后 ,KC内 ,尤其是棘层及颗粒层KC内出现大量、呈单个分布的MS。结论　EMU内KC MC协同功能增强及从基底层到颗粒层的KC内出现大量大体积、呈单个形式分布的MS ,是造成过度皮片色素沉着的直接原因     

Treatment by continuous renal replacement therapy in patients with burn injuries

Continuous renal replacement therapy (CRRT) is a relatively new therapeutic procedure which helps in the treatment of critically ill patients with renal failure as well as those without renal failure. CRRT effectively removes urea and creatinine and maintains a balanced milieu interleur and water balance. A role in the elimination of pro-inflammatory cytokines is also ascribed to this method. Most frequently venovenous haemofiltration and venovenous haemodiafiltration are used. The authors present their experience with the CRRT treatment of 40 patients in the Burn Centre Ostrava and with the results attained.     

广泛头皮深度烧伤伴颅骨全层坏死的治疗

我们自1990年4月至1993年5月共治疗8例广泛头皮深度烧伤伴有颅骨全层坏死的病例,早期经头颅 CT 及~(99m)锝同位素颅骨扫描检查明确颅内损伤及颅骨坏死范围后,采用吻合血管的血流量大的肌皮瓣或游离皮瓣移植,在保留坏死颅骨情况下Ⅰ期修复创面。8例中4例创面Ⅰ期愈合,另3例在已愈合皮瓣保护下多次清创去除死骨。经术后1～4年随访表明,坏死颅骨作为修复支架保留,避免了颅骨缺损可能造成的并发症及后遗症。本组仅1例于入院后24 h 因颅脑严重损伤而死亡。我们所介绍的这一方法为类似严重病例的治疗提供了有效手段。     

广泛头皮深度烧伤伴颅骨全层坏死的治疗

我们自１９９０年４月至１９９３年５月共治疗８例广泛头皮深度烧伤伴有颅骨全层坏死的病例，早期经头颅ＣＴ及￣９９ｍ锝同位素颅骨扫描检查明确颅内损伤及颅骨坏死范围后，采用吻合血管的血流量大的肌皮瓣或游离皮瓣移植，在保留坏死颅骨情况下Ⅰ期修复创面。８例中４例创面Ⅰ期愈合，另３例在已愈合皮瓣保护下多次清创去除死骨。经术后１～４年随访表明，坏死颅骨作为修复支架保留，避免了颅骨缺损可能造成的并发症及后遗症。本组仅１例于入院后２４ｈ因颅脑严重损伤而死亡。我们所介绍的这一方法为类似严重病例的治疗提供了有效手段。     

Cement burn of the skin during hip replacement

We present the first reported case of a partial thickness burn to the skin from discarded bone cement during a routine total hip replacement (THR). The patient required plastic surgical attention for 5 months before the skin was healed. We summarise the reported incidents of cement burns to various other structures and the circumstances in which these injuries can potentially occur.