Effects of fragment on the severity of blast injuries in dogs

Objective To explore the effects of fragment on the severity of blast injuries.?Methods Thirty six mongrel dogs were used in this study. According to the physical parameters of fragment and shock waves,models of mild blast injury,moderate blast injury,high velocity fragment injury combined with mild and moderate blast injury and low velocity fragment injury combined with moderate blast injury were established respectively. Blast injury was produced by the BST I shock tube. Fragment injury was established by shooting the animals at the thigh with a 0.48g triangular fragment. Combined injuries were inflicted by shooting the animals with fragment once the blast injury was established. The morphological changes and lung body weight index were observed 24h after injury.?Results The results showed that the high velocity fragment injury aggravated the blast injury to moderate blast injury, the most commonly injured organ was the lung,of which the severity was aggravated by one grade. High velocity fragment showed did not show aggravate effects on mild blast injury, and low velocity fragments did not show aggravate effect to moderate blast injury.?Conclusion The extremity injuries caused by high velocity fragments will aggravate blast injury of the lungs by one grade to moderate blast injury,which may be of significance for guiding the fluid resuscitation of the victims of explosion.