不同海战环境爆炸后比格犬颅内外压力变化特点的实验研究

Relationship between Beagle’s intracranial pressure and external pressure after explosion

目的通过检测不同环境爆炸后比格犬颅内外压力变化特点,明确冲击波在颅内的传播规律。方法实验动物选用健康成年比格犬46只,分别进行了自由场、舱室和水下3种环境下的实验爆炸研究,分别采用0.65、1.00和3.50 kg圆柱形三硝基甲苯爆源。自由场和舱室实验中,比格犬麻醉后,卧姿固定在与爆源一定距离的位置,头部正对爆源;水下实验中,比格犬麻醉后用救生圈固定,头部露出水面。测量比格犬头部所在位置的外界冲击波压力、颅内来自颅骨方向和脑组织方向的冲击波压力。不同时间点采用大动物神经功能评分法进行评定,观察动物损伤情况。结果自由场和舱室环境实验中,冲击波能够穿透颅骨进入颅内,且仅表现为波幅的下降,冲击波形态及变化规律与外界冲击波基本一致。自由场冲击波穿透颅骨进入颅内后,其峰值呈指数下降(相关系数R^2=0.804)。自由场和水下研究发现,来自脑组织方向的冲击波形态及变化规律也与外界冲击波基本一致,说明冲击波能够通过躯体传至脑部,其中水下研究发现,来自脑组织方向的冲击波峰值强度与外界相比,也存在指数级别的下降(相关系数R^2=0.767)。舱室爆炸冲击波形式复杂,未发现颅内外冲击波峰值存在明确的数值关系。不同环境下,比格犬的损伤程度顺序是:水下>舱室>自由场。结论在不同爆炸环境中,冲击波能够通过颅骨或胸腹腔上传作用进入颅内,但冲击波的影响因素复杂。

Objective To investigate the changes of Beagle’s intracrannial pressure after explosion and explore the features of shock wave in the cranium.Methods Forty-six healthy adult Beagle dogs were used in the experiment.The explosion was carried out in free field,in the cabin and under the water.The explosion source was 0.65,1.00 and 3.50 kg column-shaped tri-nitro-toluene.In free field and cabin explosion,Beagle dogs were anaesthesized and fixed in supine position with the head toward the explosion source.In under-water explosion,the dogs were fixed in life buoy with head above the water.The external shock wave pressure,intracranial shock wave pressure from cranium and brain tissue were measured.Neurological scores for big animals were used to assess trauma severity of the animal at different time points.Results In free field and cabin experiment,the shock wave can penetrate the cranium and enter the brain.After passing through the cranium,the shock wave only shows a decrease in amplitude,and the wave form was similar as that of the field.In free field explosion,there was exponent relationship of the peak value of the wave between those in the field and those passing through the cranium(R^2=0.804).In free field and under-water experiment,the wave form of that coming from the brain tissue was similar as that of the field,which means that shock wave can entering brain tissue from chest and abdomen.In under-water explosion,there was exponent relationship of the peak value of the wave between those in the field and those coming through the cranium(R^2=0.767).In cabin explosion,the wave form was very complex because of the complicated influence factors.No clear relationship of peak wave was discovered between those in the field and in the cranium.There was the most serious severity of the animal in under-water group and the lightest in free field.Conclusion In different explosion field,shock wave can enter into cranium either by passing through the cranium or entering brain tissue from chest and abdomen.The wave form was affected by many factors.