中国家猪深Ⅱ度烧伤削痂创面保留变性真皮与自体皮移植的实验研究

Experiment on the tangential excision of deep partial thickness burn wounds with reservation of denatured dermis and auto-skin grafting in chinese domestic pigs

目的通过研究烧伤创面的细菌量与植皮成活率的关系,比较保留不同变性真皮的厚度与植皮成活率有无差异,为临床应用提供一定的理论基础。方法中国家猪7头,在每头猪脊柱一侧用直径5.5cm、厚度2cm、温度为100℃钢板作用10s,造成7个深Ⅱ度烧伤创面,分别于烧伤后24、48、72、96、120、144、168h各时相点取材,1h内进行菌种鉴定和细菌定量分析。每处创面标本切取完毕,用辊轴取皮刀削除该创面痂皮至健康组织层行自体皮移植(电动刀取皮厚度0.25mm,)妥善包扎,单笼饲养。于术后7d计算90%植皮成活率。用同样烧伤模具,在每头猪脊柱的另侧制成4个深Ⅱ度烧伤创面,将28处创面按随机区组分组法分为7个区组,每区组4处创面。电动取皮刀定量保留烧伤皮肤厚度分别为0.83mm、0.70mm、0.38mm、0.14mm,用手术刀垂直创面无序划"#"至创面渗血,每个创面移植0.25mm厚自体皮,无菌纱布、自黏弹性绷带包扎,单笼饲养,术后7d计算植皮成活率。结果烧伤后72h内创面菌量≥105cfu/g为4.8%(1/49),以单一细菌为主,植皮成活率>90%占71.40%。超过72h,创面细菌量≥105cfu/g为67.9%以两种或三种细菌为主,植皮存活率>90%占32.1%。保留不同厚度的变性真皮,植皮成活率不同,P<0.001,真皮厚度为0.14mm时,植皮成活率最高,其次为0.38mm。结论深Ⅱ度烧伤创面于伤后3d内削痂为宜,削痂后保留变性真皮的厚度为0.1mm左右时植皮成活率较高。

Objective To explore the relationship between the bacterial quantity and the survival rate of the skin graft in the burn wound and the relationship between the thickness of the reserved denatured dermis and the survival rate of the skin graft,in order to provide some theoretical basis for clinical application.Methods In each of seven Chinese domestic pigs,seven deep second degree burns were produced on the back with spinal column with a 100 ℃ steel plate whose diameter was 5.5 cm and thickness was 2 cm.Tissue samples were harvested at 24,48,72,96,120,144 and 168 hours after burn,and analyzed for identification of bacterial strain and quantitative analysis of bacterial quantity.After the collection of tissue sample at each wound,the wound crusts were removed with a Humby knife till the appearance of the normal tissue layer.After auto-skin was transplanted(0.25 mm thick of auto-skin was obtained by using electric knife),wound was bandaged appropriately,and then the pigs were raised in separate cages.The survival rate of the skin graft was calculated 7 days after the surgery.With the same burning tool,four deep second degree burns were produced on the back of each pig to the opposite side of the spinal.All the 28 burn wounds were randomized to 7 blocks,4 burn wounds per block.By using motor dermatome,the skin at burn wounds were reserved quantitatively to the thickness of 0.83 mm,0.70 mm,0.38 mm and 0.14 mm for each of the wound per block,respectively.With surgery knife,the'#'shapes was scratched randomly and vertically to the wound till blood oozing from the wound surface.After 0.25 mm thick of auto-skin was transplanted on each wound,the wound was bandaged with sterile gauze pad and adhesive elastic bandage,and then the pigs were raised in separate cages.The survival rate of the skin graft was calculated 7 days after the surgery.Results At 72 hours after burn,the bacterial quantity was more than 10 5 cfu /g in 1(4.8%) out of 49 wounds,and mostly containing single bacterial type.Survival rate of skin graft was higher than 90% in 71.4% of the wounds at 72 hours.After 72 hours,the bacterial quantity was more than 10 5 cfu /g in 67.9% of the wounds,and mostly containing two or three bacterial types.Survival rate of skin graft was higher than 90% in 32.1% of wounds after 72 hours.Retained denatured dermis of different thickness,different skin graft survival rate,P < 0.001,the dermal thickness of 0.14 mm,the graft survival rate was highest,followed by 0.38 mm.Conclusions For deep second degree burns,it is appropriate to remove the wound crust 3 days after burn,and the survival rate of skin graft is highest when about 0.1 mm thick of denatured dermis is reserved after removing the wound crust.