摘要:
Objective To observe the effects of vacuum-assisted closure (VAC) on the inflammatory response and the rate of wound vascularization in experimental high-voltage electrical burn in pigs.Methods Four pigs (8 hind limbs) were used to reproduce the model of high-voltage electical burn with the wound.The experimental animals were randomly divided into common dressing group and VAC group.The four limbs in common dressing group were given the dressings with iodine oil every two days) and those in VAC group were given the dressings every three days.We detected the limb diameter and observed the inflammatory response at different time points (0,30 min,6 h,1,3,6,and 9 days).At the same time points,the number of white blood cells in the peripheral venous blood was counted after the wound.We also detected the muscle response in the wound center,edge and 5 cm far from the wound edge at the different time points after the wound (1,3,6,and 9 days).The muscle and vascular pathological changes were observed by hematoxylin-eosin staining,and the vwF expression was detected on the wound by immunohistochemistry staining to calculate the microvascular density (MVD) value.Results The wounds turned to eschar and the limb enlarged and exuded obviously while the necrosis get worse graduately to the Ⅲ-Ⅳ degree wound.The color,enlargement and exudation in limbs of VAC group got better gradually and the inflammatory response was milder than in the common dressing group.There was significant difference between two groups at 30 min,and 1 and 3 days [VAC group:(21.30 ±0.48),(22.35 ±0.51),(21.60 ± 0.64) cm; common dressing group:(19.48 ± 0.37),(19.33 ± 0.59),(18.80 ± 0.79) cm ;P <0.05].The hematoxylin and eosin (HE) staining showed the muscle necrosis and limb enlargement were obvious at 1 and 3 days,and the new blood vessels increased and the inflammatory cell infiltration was more obvious in VAC group at 6th and 9th day.The MVD value and white blood cell number were significantly different at 6th and 1st day,respectively [34 ±7 vs.23 ±4,P <0.05 ; (25.70 ± 3.50) × 109/L vs.(19.6 ±0.74) × 109/L,P <0.01].Conclusion VAC is useful to treat the enlargement and inflammatory response after the electrical burn and increases the wound vascularization.%目的 观察封闭负压创面治疗对猪肢体高压电烧伤炎性反应及创面血管化的影响.方法 4只雌性巴马小型猪(8后肢)制成后肢跗关节内侧高压电烧伤模型.随机分为换药组(A组)、封闭负压创面治疗组(B组),换药组用活力碘油纱换药,于伤前、伤后30 min、1、3、6、9d测量肢体周径;于伤前、伤后30 min、6h、1、3、6、9d取外周静脉血检测白细胞计数;于伤前、伤后1、3、6、9d分别取肌肉组织进行苏木素-伊红(HE)染色观察肌肉组织、血管病理变化,免疫组织化学法检测创面Ⅷ因子相关抗原(vWF)的表达,计算微血管密度(MVD)值.结果 (1)电伤后即刻形成焦痂创面,肢体红肿及渗出明显,并随时间推移坏死组织渐进性扩大,形成Ⅲ~Ⅳ度电烧伤创面;与换药组比较,封闭负压创面治疗组猪肢体红肿、渗出反应消退较快,炎性反应较轻.(2)肢体周径肿胀观察总体趋势有差异(F=11.350,P<0.05),A组与B组差异有统计学意义,其中两组间比较,伤后30 min、1d、3d差异有统计学意义[A组(21.30 ±0.48)、(22.35 ±0.51)、(21.60±0.64)cm;B组(19.48 ±0.37)、(19.33±0.59)、(18.80±0.79)cm,P<0.05);(3)组织学观察见电伤后1、3d创面HE染色可见肌肉组织坏死、水肿明显及少许炎性细胞浸润;伤后6d有新生毛细血管,炎性细胞浸润更加明显;伤后9d肉芽组织形成及新生毛细血管数量明显增多;(4)免疫组织化学法观察在电伤后6d,MVD值差异有统计学意义[(34±7)比(23±4)个;P<0.05];(5)白细胞计数(WBC)2组间比较总体趋势差异有统计学意义(F =6.743,P<0.05),伤后1d,A组与B组差异有统计学意义[(25.70±3.50)×109/L比(19.60±0.74)×109/L,P<0.01].结论 封闭负压创面治疗有利于减轻电烧伤后猪肢体肿胀、炎性反应,促进创面血管化形成.