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BOMB AND BLAST INJURIES
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Blast injuries using conventional weapons have emerged as the terrorist weapon of choice. Terrorist attacks have increased dramatically over the last decade. The National Counterterrorism Center reported more than 14,000 terrorist attacks in 2007, with 44,000 injuries and 22,000 deaths, which was a 20% to 30% increase over 2006.1 Explosive devices in military conflicts have killed or injured more than 25,000 U.S. and Coalition forces and more than 100,000 Iraqis.1 Blast injuries are increasing in the civilian setting, particularly suicide bombings, and emergency personnel must be familiar with the management and treatment of blast injuries, ad potential mass casualty incidents.2,3,4,5,6,7,8,9 The United States is not immune from intentional bombings, with about 36,000 bombing incidents reported from 1983 to 2002 - including explosive, incendiary, premature, and attempted bombings.6 There were 281 injured in the 2013 Boston Marathon bombing, with most injuries involving the lower extremities and soft tissue.8 Death, survival, and hospitalization rates vary greatly, depending on the type of explosive, distance from the explosion, and whether the explosion occurred in an open or closed space. Although some victims die immediately at the scene, the majority of injuries suffered by the immediate survivors of bombings are potentially survivable. Blast injuries commonly occur not as isolated incidents, but as part of multiple-casualty incidents of varying sizes. This pattern, combined with the fact that most emergency physicians have never encountered a blast injury victim or a true mass casualty incident, makes the care of often eminently salvageable victims contingent upon appropriate training and skill retention by the individual emergency physician, along with appropriate institutional leadership, planning, and preparation.
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Terrorist bombings result in high injury scores for victims as well as higher hospital resource use by victims than by victims of other trauma. Blast victims have increased immediate scene mortality, greater hospital mortality, more frequent need for surgical intervention, longer hospital stays, and greater use of critical care.
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An explosion is the instantaneous transformation of a solid or liquid into a gas, releasing tremendous kinetic and heat energy. Detonation of a conventional high explosive generates a blast wave that spreads out from the detonation point and displaces air, water, or anything in its path. The blast wave consists of two parts: a shock wave of high pressure followed closely by a blast wind, which is air mass in motion. The blast wave loses its energy over distance and time.
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There are four main types of blast effects. A primary injury is caused by a direct effect of blast wave overpressure on tissue. Primary blast injury mostly (but not exclusively) affects air-filled structures such as the lungs, ears, and GI tract, by the following mechanisms: spalling, ...