BLAST INJURIES
Overview: What is a blast injury?
When a blast injuries occur during an explosion occurs, people are frequently injured. The on-going wars in Iraq and Afghanistan have resulted in thousands of people being injured by explosions. Unfortunately, we see news stories about “roadside bombs,” “improvised explosive devices,” or “suicide bombers” practically every day. Doctors are beginning to better understand and treat blast injuries how people are injured during explosions, and this knowledge has resulted in better treatment.
What causes a blast injury?
A blast injury is harm done to a person from an explosion. Today, explosions happen both on the battlefield and in cities around the world. Terrorists have become very good at placing explosives in crowded areas, causing harm to large numbers of innocent people. In today’s world all doctors, regardless of where they live, should be familiar with the basics of blast injuries.
In traditional warfare, there are obviously many causes of explosions. bombs, grenades, missiles, and landmines can cause blast injuries. have been around for decades or even centuries. Military physicians have been dealing with blast injuries since the beginning of modern warfare.
Recently, terrorists have started using other methods of hurting large numbers of people with explosions. In Iraq and Afghanistan, care and roadside bombs, and suicide bombings are often used to injure soldiers while driving. The bombs are becoming more and more sophisticated, with some now using advanced “shape charges” to penetrate even the thickest vehicle armor. Some roadside bombs even use very complicated electronic sensors to set them off.
Suicide bombers are also used by terrorists to kill and injure people. The suicide bomber hides explosives under his or her clothing, then tries to get close to their target, and then blows up the explosives. The target can be one person or a large group of people.
Vehicles can also be used as bombs. Cars or trucks can be filled with explosives and driven into or parked beside a target, then detonated. The Oklahoma City Federal Building was destroyed by a truck filled with explosives in 1995, and 168 people were killed and many more injured. Today, car bombs are frequently used by terrorists in Iraq and have killed countless innocent Iraqi civilians.
But, there are frequently explosions that are not caused by war or terrorism. Industrial accidents, such as explosions in factories, also occur. regularly. Explosions are also often part of explosive car, train, or plane crashes, and explosions caused by fires also result in blast injuries. Fires in buildings often result in explosions when fuel or gas ignites. As we will see, regardless of the cause of the explosion, injuries can result for many reasons.
How do explosions injure people?
There are several ways that an explosion can cause harm to a person. When an explosion occurs, several things happen all at once. Injuries result from any combination of the forces that we will discuss below. Factors that affect how badly a person is injured during an explosion include the size or force of the explosion, how far the person is from the explosion, and what objects are around the person at the time of the blast.
First, Explosions result in a pressure wave or blast wave This is like a very powerful sound wave that is made by the air around the explosion being pushed away at an incredible speed. If you have ever been to a rock concert, you may have felt the sound waves from the stage thumping through your body. This, magnified several hundreds or even thousands of times, is like the blast wave from a large explosion. The blast wave itself that can cause harm to the human body. Organs like the brain, intestine, liver, kidneys, or lungs can be damaged by this pressure wave. The internal damage to these organs can even occur without any signs of injury at all on the outside of the body. Concussions can results, as well as internal bleeding or rupture of the intestines. The blast wave alone can be enough to kill a person.
The eardrums are often times ruptured by the blast wave from explosions. Depending on the power of the blast and how far away the victim is, permanent hearing loss or deafness can result.
Next, a person may be Injury may also result from being thrown by the blast. When the explosion occurs, the blast wave can throw a person with great force, even lifting the up off the ground. The person can then hit an object like a wall, car, or tree. People thrown by explosions can hit with force just like a car crash, and many types if injures can result. Broken bones, head injury, and even internal bleeding can result from hitting objects after an explosion.
When something explodes, pieces of debris get picked-up and thrown along with the blast wave. Whatever material is thrown by the explosion, Being struck by debris can also cause serious injury. or death when it hits a person. These pieces of material are called “secondary projectiles” and can be metal, glass, rocks, wood, or any other object near the explosion. For example, military grenades are designed to throw small pieces of metal when they explode. When a car bomb explodes, pieces of the car are thrown at remarkable speeds. If a person is inside a building when a bomb goes off outside, flying glass can become a very dangerous secondary projectile. In some explosions, the victim’s body can be hit by hundreds of small secondary projectiles. Several experts think that secondary projectiles are the most dangerous part of an explosion, and cause the most deaths.
Next, people can get burned in an Explosions can cause serious burn injuries. The explosion itself is, of course, extremely hot. But, fires started by the explosion itself result. For example, when a roadside bomb goes off and a military vehicle gets hits, the gas tank of the vehicle can explode also, resulting in massive fires. Anything near an explosion can catch on fire. Victims of explosions almost always have burns.
Finally, Explosions can also cause what is called “inhalation injury.” When something explodes and the temperatures in the explosion are very high, dangerous gases can be breathed in by the victims of the explosion. Thick, noxious smoke can damage the victim’s lungs. In industrial accidents, harmful chemicals released by explosions can be very dangerous when inhaled.
So, there are several ways which a person can be hurt by an explosion. No two blast injuries are the same. Sometimes people have such different injury patterns that is just does not seem to make sense. One person can be killed or severely injured, and the person sitting right next to them can be relatively unharmed. The forces at work in an explosion are very complicated and unpredictable.
How is it diagnosed and treated?
The most important part of treating someone who has been involved in an explosion is to perform a very complete work-up. Sometimes it is easy to get distracted by the obvious injuries and miss other important ones. For example, if a person has had their leg blown off, it is easy to focus all of your attention on the leg while missing a head injury. So, a systematic approach is required. Doctors who regularly treat trauma victims have a stepwise approach to managing all injured patients. However, understanding the principles of blast injuries helps doctors become aware of some possible injures that may not be obvious. Blast injuries are treated in steps:
1) Thorough examination of the entire body, including xrays. Always look at the victim’s entire body. Every inch of their body must be examined for signs of penetration. Small pieces of metal or glass can cause very small skin holes on the outside, but can still hit vital organs or blood vessels on the inside. All puncture wounds must be thoroughly examined and x-rays done as needed.
2) CT scans of the head if unconscious or confused Always anticipate a head injury. If the patient is confused at all, does not remember the event or is acting strangely, they may have a brain injury form the blast wave and they should get a CT scan of their head.
3) Examination of eardrums to check for ruptures The ears of every patient should be examined. The eardrum should be looked at for signs of rupture. Once the patient is stable and recovered, a formal hearing test done by an audiologist should be considered.
4) Be aware of possible internal bleeding or internal damage. We discussed above how the liver, spleen or kidneys can be damaged by the blast wave. This bleeding can be slow, and it may take several hours to recognize. A CT scan of the abdomen to check for internal injuries should be considered in all blast injured patients. If a CT cannot be done, the patient should be observed for a several hours or even days to make sure that internal bleeding does not occur. Blast wave injuries to the intestines can take two or three days to be recognized. Even if a patient is sent home from the hospital, they should be counseled on what sort of symptoms are worrisome, and instructed to return to the hospital immediately should those symptoms occur.
5) Always look for inhalation injury. The lung damage caused by breathing in harmful fumes and smoke may not make the patient sick for several hours after the explosion. All blast victims should have a Chest x-rays to check for inhalation injury, and if their breathing worsens the chest x-ray should be repeated. All victims should be placed on monitors to follow their blood oxygen levels. Blast victims can require oxygen masks or may even need to be put on a ventilator if lung damage is severe.
Since explosions are often random accidents or seemingly random acts of violence, victims can be very troubled by the experience. They may have witnessed other people around them horribly injured or killed. Post-traumatic stress disorder may occur following a blast injury. is a very well studied condition that can ruin a victim’s life and even lead to suicide. All patients who have been involved in explosion, especially those caused by terrorist acts, should be referred to a Consultation with a mental health professional may help. or a complete evaluation. Sometimes the most devastating consequences of a blast can be emotional. The mental health of the victim is just as important, in the long run, as their physical injuries.
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Copyright 2007, MD Kiosk
