开放爆炸环境下烧冲复合伤动物模型建立的研究

Establishment of an animal model with burn-blast combined injury in the open explosive environment

目的建立理想的开放爆炸环境下烧冲复合伤动物模型。方法以Wistar雌性清洁级成年大鼠460只为研究对象。随机选取90只大鼠设为预实验组,其余370只大鼠随机选取360只大鼠设为实验组,剩余10只大鼠设为正常对照组。预实验组90只大鼠随机分为预单纯烧伤组(n=30),预烧冲复合伤组(n=30),预烧冲复合伤组(n=30);预单纯烧伤组采用凝固汽油涂抹背部点燃25 s造成深Ⅱ度烧伤,烧伤面积分别为10%总体表面积(TBSA)(轻度,n=10)、25%TBSA(中度,n=10)、40%TBSA(重度,n=10);预单纯冲击伤组采用柱形黑索金炸药在不同距离(70、50、30 cm)造成轻度、中度、重度冲击伤(每组n=10);按照预单纯烧伤组及预单纯冲击伤组动物死亡率及器官功能障碍等,确定轻度、中度、重度的预烧冲复合伤模型:预轻度烧冲复合伤(轻度烧伤+轻度冲击伤),预中度烧冲复合伤(中度烧伤+中度冲击伤),预重度烧冲复合伤(重度烧伤+重度冲击伤);观察伤后24 h大鼠宏观变化及死亡率。实验组370只大鼠随机分为单纯烧伤组(n=120,其中轻、中、重3组,每组n=40),单纯冲击伤组(n=120,其中轻、中、重3组,每组n=40),烧冲复合伤组(n=120,其中轻、中、重3组,每组n=40),正常对照组(n=10),模型的建立同预实验,伤后6 h、1 d、2 d、3 d用自动生化仪检测实验组大鼠血清肌酸激酶同工酶(CK-MB)、谷丙转氨酶(GPT)、血肌酐(Scr),并同时观察实验组大鼠死亡率及用光学显微镜观察各脏器病理变化。结果预轻、中、重度冲击伤组大鼠伤后24 h死亡率分别为10%、30%、100%;预轻、中、重度烧伤组大鼠伤后24 h死亡率分别为10%、20%、40%;预轻、中、重度烧冲复合伤组大鼠伤后24 h死亡率分别为20%、30%、100%;预冲击伤组:预重度冲击伤组大鼠均可见骨膜穿孔,均有球结膜出血,9例可见口腔黏膜破溃出血。预中度冲击伤组大鼠仅1例出现可见骨膜穿孔,9例出现球结膜出血,5例可见口腔黏膜破溃出血。预轻度冲击伤组大鼠未见骨膜穿孔及球结膜出血,未见口腔黏膜破溃出血。预单纯烧伤组:创面渗出较少,未见明显分泌物形成。预烧冲复合伤组:各器官表现基本同预单纯冲击伤组,创面变化基本同预单纯烧伤组。实验组大鼠伤后6 h、1 d、2 d、3 d的死亡率:单纯冲击伤组:轻度冲击伤组各时相点的死亡率分别为2.5%、10%、10%、10%,中度冲击伤组各时相点的死亡率分别为5%、20%、30%、40%,重度冲击伤组各时相点的死亡率分别为15%、50%、65%、75%,单纯烧伤组:轻度烧伤组各时相点的死亡率分别为5%、10%、20%、20%,中度烧伤组各时相点的死亡率分别为5%、20%、30%、30%,重度烧伤组各时相点的死亡率分别为10%、40%、65%、75%;烧冲复合伤组:轻度烧冲复合伤组各时相点的死亡率分别为7.5%、20%、20%、20%,中度烧冲复合伤组各时相点的死亡率分别为10%、30%、40%、40%,重度烧冲复合伤组大鼠伤后6、24 h的死亡率分别为25%、100%。轻度烧冲复合伤组CK-MB在伤后1 d增加明显,伤后2 d迅速下降,伤后3 d接近正常水平。GPT、Scr未见明显变化。中度烧冲复合伤组伤后6 h至伤后3 d均伴有不同程度器官功能障碍,CK-MB、GPT、Scr测定出现持续性异常增高。心脏:CK-MB在伤后6 h即开始增加,伤后1 d增加明显,至伤后2 d逐步下降,伤后3 d仍高于正常水平;肝:GPT在伤后6 h即开始异常,伤后1 d进一步增加,至伤后2 d达峰值,伤后3 d仍高于正常水平;肾:Scr在伤后6 h变化不明显,伤后1 d略有增加,至伤后2 d增加明显,伤后3 d略有下降仍高于正常水平,伤后2 d中度烧冲复合伤组大鼠CK-MB(241.42±33.31)HU/L、GPT(127.71±11.54)U/L、Scr(95.37±13.02)μmol/L与正常对照组(84.12±12.64)HU/L、(42.28±10.44)U/L、(53.53±12.71)μmol/L比较,差异有统计学意义(t=3.327、4.081、2.508,P<0.05);重度烧冲复合伤组CKMB、GPT、Scr均在伤后6 h即开始异常明显增加。心、肝、肾、肺脏、小肠均有不同程度出血、充血、炎症反应等病理学改变。结论根据实验组动物死亡率,以及存活动物脏器功能及病理形态学变化情况进行判断,中度烧冲复合伤组是较理想的烧冲复合伤动物模型。

Objective To establish an animal model of burn-blast combined injury in the open explosive environment.Methods All 460 female Wistar rats were involved in this study.Ninty rats were randomly divided into pre-experiment group,the other 370 rats were randomly selected 360 rats as the experiment group,10 rats were divided into normal control group.The rats in pre-experiment group were randomly divided into pre-burn group（n=30）,pre-blast injury group（n=30）,pre-burn-blast combined injury group（n=30）,rats in pre-burn group were burned with napalm smear on back for 25 seconds in order to replicate deep partial thickness burn,the TBSA of burned area was 10%（n=10）,25%（n=10）, and 40%（n=10）.The column explosives RDX was used in pre-blast injury group at different distance in order to replicate mild,moderate,severe blast injury.The models of the mild,moderate,severe pre-burn-blast combined injury were replicated according to the mortality and incidence of multiple organ dysfunction in pre-burn group and pre-blast injury group.Mild pre-burn-blast combined injury was combined with mild burn and mild blast injury,moderate pre-burn-blast combined injury was combined with moderate burn and moderate blast injury,severe pre-burn -blast combined injury was combined with severe burn and severe blast injury.The mortality rate and macroscopic changes were observed 24 hours after injury.Three hundred and seventy rats in experiment group were randomly divided into burn group（n=120,the mild,moderate, severe in 3 groups）,blast injury group （n =120,the mild,moderate,severe in 3 groups）,burn-blast combined injury group（n=120,the mild,moderate,severe in 3 groups）,and control group（n=10）.The establishment of the model was the same with pre-experiment. The mortality,serum creatine kinase isoenzyme （CK-MB）,alanine aminotransferase（GPT）,serum creatinine （Scr）and the changes pathology were observed in experiment group in 6 h,1 d,2 d,3 d after injury.Results The mortality in mild, moderate,severe pre-blast injury groups was 10%,30%,and 100%in 24 hours after injury.The mortality in mild,moderate,severe pre-burn injury groups was 10%,20%,and 40%.The mortality in mild, moderate,severe pre-burn-blast combined injury groups was 20%,30%,and 100%.The pre-blast injury group：in 30 cm to explore resource,all of the 10 rats showed periosteal perforation and conjunctival hemorrhage,9 rats showed oral mucosal ulceration hemorrhage.In 50 cm to explore resource,only 1 rat showed periosteal perforation,9 rats showed conjunctival hemorrhage,and 5 rats showed oral mucosal ulceration hemorrhage.In 70 cm to explore resource,10 rats have no change in periosteal perforation, conjunctival hemorrhage and oral mucosal ulceration hemorrhage.Pre-burn group：the wound have a little exudation.Pre-burn-blast combined injury group：the organs showed the same performance with the pre-blast injury group ,the wound also showed the same changes with the pre - burn group .The mortality of experiment group in 6 h,1,2,3 d after injury：blast injury group：the mortality of mild blast injury group at each observation point was 2.5%,10%,10%,and 10%.The mortality of moderate blast injury group was 5%,20%,30%,and 40%.The mortality of severe blast injury group was 15%,50%,65%,and 75%.Burn group：the mortality of mild burn group at each observation point was 5%,10%,20%,and 20%.The mortality of moderate burn group was 5%,20%,30%,and 30%.The mortality of severe burn group was 10%,40%,65%,and 75%.Burn-blast combined injury group：the mortality of mild burn-blast combined injury group at each observation point was 7.5%,20%,20%,and 20%.The mortality of moderate burn-blast combined injury group was 10%,30%,40%,and 40%.The mortality of severe burn-blast combined injury group was 25%,100%.In mild burn-blast combined injury group ,the serum CK-MB increased significantly in 1 d after injury,decreased rapidly in 2 d after injury,and closed to the normal level in 3 d after injury.The serum GPT and Scr showed no changes.In moderate burn-blast combined injury group,the injury after 6 hours to 3 days was associated with multiple organ dysfunction （serum CK-MB,GPT, determination of Scr a persistent abnormal increasing ）.Heart：CK-MB increased in 6 h after injury, significantly changes in 1 d after injury,in 2 d after injury it gradually decreased,and it was still higher than normal level in 3 d after injury;Liver：GPT increased in 6 h after injury,it increased further in 1 d after injury,and it increased a peak value in 2 d after injury,and it was still higher than normal level in 3 d after injury;Kidney：Scr showed no changes in 6 h and 1 d after injury,it increased significantly in after 2 d, and it was still higher than the normal level after 3 d,in moderate burn-blast combined injury group after 2 d combined injury in rats of CK-MB （241.42 ±33.31）HU/L,GPT （127.71 ±11.54）U/L ,Scr （95.37 ± 13.02）μmol/L,with the normal control group （84.12 ±12.64）HU/L,（42.28 ±10.44）U/L, （53.53 ±12.71）μmol/L ,the difference was statistically significant （t =3.327,4.081,2.508,P〈0.05）;In severe burn-blast combined injury group,the serum CK-MB,GPT,and Scr increased abnormal obviously within 6 h after injury.The pathological changes in the hearts,livers,kidney,lungs,intestine includes hemorrhage,congestion and inflammation.Conclusions According to the animal mortality rate and survival of the animals with significant organ function and pathological changes,the animal model with moderate burn-blast combined injury was satisfied as experimental burn-blast combined injury model.