1. Medical Student Seminar
Blast Injuries
Amy Kaji, MD, MPH
November 16, 2005
Acute Care College
Medical Student Seminar

2. Iraq: Car Bombings Current Events

3. Historically in US… Few US bombings have caused mass casualties
First World Trade Center Attack, February 1993
Oklahoma City Bombing – April 19, 1995
Fuel and fertilizer used to create a bomb
518 injuries and 168 deaths
Atlanta Olympic Park Bombing, July 27, 1996
World Trade Center and Pentagon
September 11th, 2001
Explosive Device Attacks at Abortion Clinics
To date, relatively few bombings in the US (except 9/11/01) have caused mass casualties. Historically, these include 9/11, Oklahoma City bombing, the first World Trade Center attack, the Atlanta Olympic Park bombing, and explosive device attacks at abortion clinics. In 1995, fuel and fertilizer was used to create a bomb in the Alfred Murrah Federal Building in Oklahoma, causing 518 injuries and 168 deaths.

4. Oklahoma City April 19, 1995

5. New York City September 11, 2001

6. Classification of Explosives
High Order (HE) Explosive
Produce a high pressure shock wave
Examples include TNT, C-4, Semtex, dynamite
Low Order (LE) Explosive
Produce a subsonic explosion
Examples include pipe bombs, molotov cocktails
Manufactured Explosive
Standard military-issued quality-tested weapon
Improvised Explosive Device (IED)
Use a device outside its intended purpose
Commercial jet as a guided missile
Loaded with metallic objects to inflict penetrating injury
Classification of Explosives – Explosives are categorized as high-order explosives or low-order explosives. HE produce a defining supersonic over-pressurization shock wave. Examples of HE include TNT, C-4, Semtex, nitroglycerin, dynamite, and ammonium nitrate fuel oil. LE create a subsonic explosion and lack HE’s over-pressurization wave, and examples of LE include pipe bombs, gunpowder, Molotov cocktails or aircraft improvised as guided missiles. Manufactured explosives are standard military-issued mass produced and quality tests weapon. Improvised devices are weapons produced in small quantities, use a device outside its intended purpose, such as converting a commercial aircraft into a guided missile. Improvised explosive devices currently used in insurgency warfare are often loaded with metallic objects to inflict penetrating injuries in crowded civilian settings.

7. Atlanta, Georgia July 27, 1996

8. Bag with Bomb

9. Types of Blast Injuries
Primary
Due to direct effect of pressure
Secondary
Due to effect of projectiles from explosion
Tertiary
Due to structural collapse and from persons being thrown from the blast wind
Quaternary
Burns, inhalation injury, exacerbations of chronic disease
Types of Blast Injuries: Primary (direct effects of pressure, either overpressurization and underpressurization, such as rupture of tympanic membranes, pulmonary damage, and rupture of hollow viscera); Secondary (effects of projectiles, causing penetrating trauma and fragmentation injuries); Tertiary (effects of structural collapse and of persons being thrown by the blast wind, causing crush injuries and blunt trauma, penetrating trauma, fractures and traumatic amputations, open or closed brain injuries); and Quaternary (burns, asphyxia, and exposure to toxic inhalants).

10. Primary Blast Injury Unique to high explosives
Due to impact of over-pressurization wave with body surfaces
Most commonly involve air-filled organs and air-fluid interfaces
Middle ear
Lungs
Gastrointestinal tract
Types of injuries
Blast lung
Tympanic Membrane (TM) rupture
Abdominal hemorrhage and perforation
Globe rupture
Traumatic brain injury (TBI) without physical signs of head injury
Primary Blast Injuries are unique to high explosives, and these basically result from the impact of the overpressurization wave with body surfaces. The injuries are caused by barotrauma, and these injuries most commonly involve air-filled organs and air-fluid interfaces. Gas-filled structures are most susceptible, such as the middle ear, the lungs, and the GI tract. Types of injuries include blast lung, TM rupture, abdominal hemorrhage and perforation, globe rupture, and concussion (TBI without physical signs of head injury). Organs are damaged by dynamic pressure changes at tissue-density (air-fluid) interfaces due to the interaction of a high frequency stress wave and a lower frequency shear wave. Rupture of the tympanic membranes, pulmonary damage and air embolization, and rupture of hollow viscera are the most important primary forms of blast injury.

11. TM Injury TM - structure most frequently injured by blast
TM rupture
Ossicle dislocation
Disruption of oval or round window
Symptoms may include hearing loss, tinnitus, vertigo, bleeding from external canal, mucopurulent otorrhea
Otologic exam and audiometry for all
TM rupture is sensitive marker, but absence does not exclude other organ injury
Tympanic membrane is the structure most frequently injured at the lowest pressure, by blasts. An increase in pressure of as little as 5 psi above atmospheric pressure can rupture the human eardrum. Patients may manifest symptoms of deafness, tinnitus, and vertigo, which characterizes rupture of the eardrum. If dynamic pressures are high enough, the ossicles of the middle ear can be dislocated, and disruption of the oval or round window can cause permanent hearing loss. Signs of ear injury are usually present at the time of initial evaluation and should be suspected for anyone presenting with hearing loss, tinnitus, otalgia, vertigo, bleeding from the external canal, TM rupture, or mucopurulent otorrhea. All patients exposed to blast should have an otologic assessment and audiometry. Although tympanic membrane rupture is seen as a sensitive marker for blast injuries of other organs, data have shown that delayed pulmonary complications of blast injuries may not develop in persons with ruptured TMs, and there are those with pulmonary injures who do not have ruptured TMs.

12. TM Rupture

13. Blast Lung Lung – 2nd most susceptible organ to blast injury
Most common fatal primary blast injury among initial survivors
Pulmonary barotrauma includes
Pulmonary contusions
Systemic air embolism
Free radical associated injuries
Thrombosis
Lipoxygenation
Disseminated Intravascular Coagulation (DIC)
The lung is the second most susceptible organ to primary blast injury. It is the most common fatal primary blast injury among initial survivors, and pulmonary barotraumas includes pulmonary contusions, systemic air embolism, and free radical associated injuries such as thrmobosis, lipoxygenation, and disseminated intravascular coagulation (DIC).

14. Blast Lung Clinical triad of apnea, bradycardia, and hypotension
Signs usually at initial presentation but may manifest as late as 48 hours after explosion
Should be suspected if dyspnea, cough, hemoptysis, or chest pain
Radiographic findings
Bihilar “butterfly” pattern
Pneumothorax or hemothorax
Pneumomediastinum and subcutaneous emphysema
Prophylactic chest tube before general anesthesia and air transport if blast lung suspected
Signs or blast lung are usually present at the time of initial evaluation, but they have been reported as late as 48 hours after the explosion. Blast ling is characterized by the clinical triad of apnea, bradycardia, and hypotension. It should be suspected in anyone who presents with dyspnea, cough, hemoptysis, or chest pain following blast exposure. Pressure differentials across the alveolar-capillary interface cause disruption, hemorrhage, pulmonary contusion (appears as bihilar “butterfly” pattern on chest radiograph), pneumothorax, hemothorax, pneumomediastinum, and subcutaneous emphysema. Pulmonary injuries vary from selected petechiae to confluent hemorrhages. Immediate onset of pulmonary edema carries a grave prognosis. A prophylactic chest tube is recommended before general anesthesia or air transport if blast lung is suspected. Blast lung is the most common fatal injury among initial survivors. Pulmonary barotraumas is the most common critical injury to people close to a blast center, whether civilian or military.
Systemic acute gas embolism from pulmonary disruption may occlude blood vessels of the brain or spinal cord, and injury to the CNS from acute gas embolism needs to be differentiated from the direct effects of head trauma and concussion.

15. Blast Lung

16. Blast Abdominal Injury
Colon – visceral organ most frequently affected
Mesenteric ischemia from gas embolism may cause delayed rupture of large or small intestine
Intestinal barotrauma more common with underwater air blast
Solid organ injury less likely
Signs and symptoms
Abdominal pain, nausea, vomiting, hematemesis
Rectal pain and tenesmus
Testicular pain
Unexplained hypovolemia
Blast abdominal injury should be suspected in anyone exposed to a explosion with abdominal pain, nausea, vomiting, hematemesis, rectal pain, tenesmus, testicular pain, unexplained hypovolemia, or any finding suggestive of an acute abdomen. The colon is the visceral organ most frequently affected by a primary blast injury, and rupture of the colon and small intestine may occur as an immediate result of a blast. Mesenteric ischemia or infarct can cause delayed rupture of the large or small intestine. Note that clinical signs of blast-related abdominal injury may be initially silent until signs of acute abdomen or sepsis are advanced. Intestinal barotraumas is more common with underwater than air blast injuries. Rupture, infarction, ischemia, and hemorrhage of solid organs such as the liver, spleen, and kidney are generally associated with very high blast forces or proximity of the patient to the blast center.

17. Blast Abdominal Injury

18. Other Primary Blast Injuries
Eye
Globe rupture, serous retinitis, hyphema, lid laceration, traumatic cataracts, injury to optic nerve
Signs and symptoms include eye pain, foreign body sensation, blurred vision, decreased vision, drainage
Brain
TBI due to barotrauma of gas embolism
Signs and symptoms include headache, fatigue, poor concentration, lethargy, anxiety, and insomnia
Primary blast injury to the eye include rupture of the globe, serous retinitis, and hyphema lid laceration, traumatic cataracts injury to optic nerve . Primary blast injuries to the brain include concussion as well as barotraumas caused by acute gas embolism. Consider the proximity of the victim to the blast particularly when given complaints of headache, fatigue, poor concentration, lethargy, depression, anxiety, insomnia, or other constitutional symptoms. Loss of consciousness and coup and countercoup injuries formerly were considered secondary and tertiary injuries, but with the increased use of body armor in the military, damage to the CNS after an explosion has been increasingly attributed to the direct effects of the blast.

19. Globe Rupture

20. Secondary Blast Injury
Due to flying debris and bomb fragments
Penetrating ballistic or blunt injuries
Leading cause of death in military and civilian terrorist attacks except in cases of major building collapse
Wounds can be grossly contaminated
Consider delayed primary closure and tetanus vaccinations
Secondary Blast Injuries – results from flying debris and bomb fragments. Any body part may be affected, and it can result in penetrating ballistic or blunt injuries. Eye penetration may be occult. Many explosive devices contain metallic and other fragments, and these and the disintegrated casing are designed to cause penetrating wounds. Penetrating injuries from primary fragments (part of the weapon) and from secondary fragments (from the explosion) are the leading cause of death and injury in both military and civilian terrorist attacks, except in cases of major building collapse. Wounds can be grossly contaminated, and consideration should be given to delayed primary closure and tetanus vaccinations.

21. Tertiary Blast Injuries
Due to persons being thrown into fixed objects by wind of explosions
Also due to structural collapse and fragmentation of building and vehicles
Structural collapse may cause extensive blunt trauma
Crush syndrome
Damage to muscles and subsequent release of myoglobin, urates, potassium, and phosphates
Oliguric renal failure
Compartment syndrome
Edematous muscle in an inelastic sheath promotes local ischemia, further swelling, increased compartment pressures, decreased tissue perfusion, and further ischemia
Tertiary Blast Injuries – these result from people being thrown into fixed objects by the wind of explosions. Any body part may be affected, and fractures, traumatic amputations, and open and closed head injuries occur. Tertiary blast injuries also result from structural collapse and fragmentation of buildings and vehicles. Structural collapse and large airborne fragments lead to crush injuries and extensive blunt trauma, whereas flying fragments cause penetrating trauma. The crush syndrome is a metabolic derangement resulting from damage to muscle tissues and the subsequent release of myoglobin, urates, potassium, and phosphates. Oliguric renal failure, the most severe end point, causes the retention of potassium above and beyond that released from the damaged muscle. Appropriate treatment includes hydration and alkalinization. The compartment syndrome results from the compression that a damaged edematous muscle exerts within its inelastic sheath, which promotes local ischemia, further swelling, increased compartment pressures, decreased tissue perfusion, and further ischemia.

22. Crush and Compartment Syndrome

23. Potential Intra-operative and Post-resuscitation Complications
Surgeons, Anesthesiologists, and Critical Care Specialists will need to be aware of potential intraoperative and post-resuscitation complications
Occult pneumothorax
Occult compartment syndrome
Hyperkalemia
Crush syndrome
Rhabdomyolysis

24. Quaternary Blast Injuries
Explosion related injuries or illnesses not due to primary, secondary, or tertiary injuries
Exacerbations of preexisting conditions, such as asthma, COPD, CAD, HTN, DM, etc.
Burns (chemical and thermal)
White Phosphorous (WP) from munitions causes extensive burns, hypocalcemia and hyperphosphatemia
Toxic inhalation
Radiation exposure
Asphyxiation (carbon monoxide and cyanide)
Quaternary Blast Injuries – refer to explosion-related injuries, illnesses, and disease not due to primary, secondary, or tertiary injuries. These can include exacerbations or complications of preexisting conditions, such as asthma, COPD, or other breathing problems from dust, smoke, toxic fumes, etc. or as might occur in women who are pregnant or taking anticoagulants. Quaternary injuries also include burns (chemical or thermal), toxic inhalation, exposure to radiation, asphyxiation (including carbon monoxide and cyanide after incomplete combustion of materials), and inhalation of dust containing coal or asbestos. Considerations should be given to the inhalation of CO, CN, MetHgb in both industrial and criminal explosions. After an incendiary bomb attack, the number of burn injuries should be ascertained as early as possible and alternative national burn management resources should be alerted, because a large number of burn victims can quickly overwhelm local medical resources.
Patients with burns from military white phosphorous (WP) munitions are at risk for hypocalcemia and hyperphosphatemia, and these levels should be followed. When WP contacts air, it ignites, causes burns, and releases phosphorous pentoxide. WP is an ingredient of hand grenades.

25. Madrid, Spain March 11, 2004

26. General Considerations
Information about distance from and type of explosion predict injury severity and type
Confined space vs. open space
Increased number of penetrating and primary blast injuries if closed space
Intensity of explosion pressure wave declines with cubed root of distance away from explosive
Standing at 3m has 9x greater pressure than if at 6m
Blast wave reflected by solid surfaces
Person next to a wall may sustain a greater primary blast injury
General Considerations – information about the type of explosion and the target helps to predict the types of injuries. After an explosion in a confined space, such as a bus, one would anticipate, in addition to penetrating injuries, more victims with primary blast injuries and lung damage than would be expected after an explosion in an open space. Explosions in confined spaces (mines, building, or large vehicles) and or structural collapse are associated with greater morbidity and mortality. Land mine injuries are associated with a high risk of below and above the knee amputations. Fireworks-related injuries prompt and estimated 10,000 to 12,000 ED visits in the United States, with 25% involving the eye or hand. Intensity of an explosion pressure wave declines with the cubed root of the distance away from the actual explosive. That is, a person 3m from an explosion experiences 9 times more overpessure than a person who is 6m away. Thus, proximity of the person to the explosion is an important factor in a primary blast injury. Note that blast waves are also reflected by solid surfaces, and therefore, a person standing next to a wall may sustain a greater primary blast injury.

27. General Considerations
Half of all initial casualties seek medical care over first hour
Expect upside down triage
Most severely injured arrive after less injured who bypass EMS and self-transport to closest hospitals
Secondary devices
Initial explosion attracts law enforcement and rescue personnel who will be injured by second explosion
Terrorist attacks in civilian settings tend to have a biphasic distribution of mortality – high immediate rates of death followed by low early and late mortality rates.
Rarely have civilian providers faced a battlefield approach to triage or sorting. Initial stabilization of victims of blast injury like that of other trauma victims, includes assessment and management of the airway, breathing, and circulation. Half of all initial casualties will seek medical care over a one-hour period. This can be useful to predict demand for care and resource needs. Expect an upside down triage—the most severely injured arrive after the less injured, who bypass ENS triage and go directly to the closest hospitals. Another ominous consideration is the tactic of setting dual explosion, since the initial explosion may be a ploy to attract law enforcement and resuce personnel, followed by a second device designed to injure rescuers. Moreover, EMS personnel should check for radiation and chemical contamination at the scene of a deliberate attack.
Few US health professionals have experience with explosive-related injuries, as Vietnam era physicians are retiring, and until the last decade, the US was largely spared of the scourge of mega-terrorist attacks.

28. London, England July 7, 2005

29. General Management Focus on two exams Otoscopic exam Pulse oximetry
If ruptured TM, chest radiography and eight hour observation recommended
Primary blast injury notorious for delayed presentation
If nonruptured TM and no other symptoms, may conditionally exclude other serious primary blast injuries
Pulse oximetry
Decreased oxygen saturation signals early blast lung even before symptoms
Management of specific injuries – Treatment of patients after blasts focuses on two examinations. First, portable otoscopes are used to identify rupture of the tympanic membranes. If the tympanic membranes are intact, serious primary blast injuries can be conditionally excluded, in the absence of other symptoms such as dyspnea, respiratory distress, and acute abdominal pain. Patients with rupture of the tympanic membranes should undergo radiography of the chest and should be observed for at least eight hours, as clinically indicated, since primary blast injuries are notorious for their delayed onset. Second, these victims should be monitored by sequentially measuring their oxygen saturation by pulse oximetry. Decreased oxygen saturation probably signals early blast lung even before symptoms begin.

30. Treatment of Blast Lung
High inspiratory pressures increase risk of air embolism and pneumothorax
Ventilation should use limited inspiratory pressures
Permissive hypercapnia
High frequency ventilation may be of value
Treatment of blast lung is challenging in that ventilation with high peak inspiratory pressures increases the risk of air embolism and pneumothorax. Ventilation should use limited PIP and permissive hypercapnia, when available, high frequency ventilation may be of value. Assume that a patient’s wheezing associated with a blast injury is due to pulmonary contusions.

31. Pneumothorax

32. Treatment of TM rupture
Generally expectant management
Most resolve spontaneously
Avoid irrigating or probing the auditory canal
Avoid swimming
Refer to ENT if no healing or complications occur
Complications include ossicle disruption, cholesteatoma, perilymphatic fistula, and permanent hearing loss (1/3)
Steroids may be helpful in sensorineural hearing loss
Treatment of TM rupture is generally expectant: patients should avoid probing or irrigating the auditory canal, avoid swimming or immersing the head under water, take ototopical antibiotics as indicated, and be referred for potential repair if healing does not occur. Small perforations usually heal within a few weeks. Sensorineural hearing loss after a blast, in the absence of contraindications my respond to a brief course of steroids. Follow-up – most cases of TM rupture will heal spontaneously, but complications such as ossicle disruption, cholesteatoma formation, perilymphatic fistula formation, etc. are possible, and about one-third sustain permanent hearing loss. Thus, patients should be referred to ENT for follow-up, and it should be remembered that neomycin is ototoxic and is contraindicated in TM perforation.

33. Treatment for Acute Gas Embolism (AGE)
Recompression with 100% oxygen
Left lateral recumbent position
Hyperbaric oxygen (HBO) is definitive
Transfer may be necessary
Aspirin may be helpful in AGE
May reduce inflammation-mediated injury in pulmonary barotrauma
Weigh bleeding risk in acute trauma setting
Patients thought to have acute gas embolism (AGE) require recompression treatment. Place patients on 100% oxygen by tight-fitting face mask and, if possible, place them in the left lateral recumbent position. Trendelenburg (head down) position is no longer recommended. Of course, other causes of symptoms (eg, traumatic CNS injury) must be excluded. Hyperbaric oxygen (HBO) treatment is the definitive procedure. Transfer of the patient may be required. Research suggests that aspirin is helpful in AGE. Aspirin may reduce inflammation-mediated injury in pulmonary barotrauma as well. It may, however, be unwise to give an antiplatelet agent to a patient with acute trauma.

34. AGE

35. Treatment of Eye Injuries
28% of blast survivors sustain eye injuries
Objects penetrating eye (or any other body part) should not be removed in an emergency setting
Cover affected eye with a paper cup that will not exert pressure on the globe
Remove object in operating room under controlled conditions
Refer patient to ophthalmology for definitive treatment
Up to 28 percent of blast survivors may have serious eye injuries, particularly if the blast caused shattering glass. Symptoms include eye pain or irritation, foreign body sensation, altered vision, periorbital swelling or contusion, and findings can include decreased visual acuity, hyphema, globe perforation, subconjunctival hemorrhage, foreign body or lid laceration. Objects penetrating the eye should not be removed in an emergency setting. The eye can be covered with a paper cup or other clean object that will not exert pressure on the globe, and the patient can be referred for definitive surgical treatment.

36. Treatment of Burns Cover burns to minimize heat and fluid loss
WP burns require special management
Copious lavage and removal or particles and debris
Rinse with 1% copper sulfate solution
Combines with phosphorous particles and impedes further combustion
Cardiac monitor
Hypokalemia and hyperphsophatemia common
Use moistened face masks to protect from phosphorous pentoxide gas exposure
Avoid use of flammable anesthetic agents and excessive oxygen
Before a patient is transported to a burn unit, burns should be covered to prevent heat loss and to minimize fluid loss due to disruption in dermal integrity.
WP burns require unique management. Initial management of WP contaminated burns consist of copious lavage of the area with water, removal of particles and debris, and covering the area with saline-soaked gauze. Definitive treatment consists of a rinse using 1% copper sulfate (CuSO4) solution and removing the WP particles. Copper sulfate combines with phosphorous particles to create a blue-black cupric phosphide coating. This impedes further WP combustion and makes particles easier to find. Never apply copper sulfate as a dressing. Excess copper sulfate absorption can cause intravascular hemolysis and renal failure. WP injury can lead to hypokalemia and hyperphosphatemia with ECG changes, cardiac arrhythmias, and death. Place the patient on a cardiac monitor and closely track serum calcium levels. Intravenous (IV) calcium may be required. Moistened face masks and good ventilation help protect patients and medical personnel from the pulmonary effects of phosphorous pentoxide gas. Naturally, avoid the use of flammable anesthetic agents and excessive oxygen around WP.

37. WP Smoke Hand Grenade

38. WP Burn Victim

39. Special Populations
Pediatric trauma due to terrorism vs. pediatric trauma due to non-terrorism related events
Increased use of Intensive Care Unit (ICU) resources
Higher injury severity scores (ISS)
Longer hospital stays
Pregnancy
Direct injury to fetus is uncommon
Fetus protected by amniotic fluid
Fetal attachment to placenta is tenuous
Risk for placental abruption
If blast in second or third trimester admit to labor and delivery for fetal monitoring
Children who are victims of terrorism require more resources of ICUs, have higher ISS, and have longer hospital stays than children who survived traumatic events unrelated to terrorism.
During pregnancy, the direct injury of the fetus by the blast is uncommon, as the fetus is apparently protected by amniotic fluid. However, its attachment to the placenta is at risk, if the blast wave affects the high-density uterine wall and the lower-density placental medium, causing placental abruption. For women exposed to blasts in the second and third trimester of pregnancy, admission to the labor and delivery area for fetal monitoring is recommended.

40. Guidelines for Disposition
Limited data prevent establishing optimal duration of observation
Low risk and may be discharged with strict precautions after four hours of observation:
Persons exposed to open-space explosions with no apparent significant injury, normal vital signs and unremarkable lung and abdominal examination
Moderate risk and should be observed for longer periods of time for delayed complications:
Persons exposed to closed-space explosion or in-water explosions
Persons with TM rupture
Guidelines for disposition - Limited data prevent establishing the optimal duration of observation.
Persons exposed to open-space explosions who have no apparent significant injury and with normal vital signs and unremarkable lung and abdominal examinations generally can be discharged after 4 hours with instructions to return to the ED if shortness of breath, abdominal pain, vomiting, or other symptoms occur.
Persons exposed to significant closed-space explosions, in-water explosions, and those who incur TM rupture are at higher risk of delayed complications. These patients should receive more intensive observation over a longer period. Motivated, reliable, and completely asymptomatic patients may be sent home after 4 hours of observation.
Admit to the hospital all patients with significant burns, suspected air embolism, radiation or WP contamination, abnormal vital signs, abnormal lung examination findings, clinical or radiographic evidence of pulmonary contusion or pneumothorax, abdominal pain, vomiting, evidence of renal contusion/hypoxia, or penetrating injuries to the thorax, abdomen, neck or cranial cavity.

41. Guidelines for Admission
High risk patients who require admission
Significant burns
Suspected air embolism
Radiation
WP contamination
Abnormal vital signs
Abnormal lung examination findings
Clinical or radiographic evidence of pulmonary contusion or pneumothorax
Abdominal pain or vomiting
Penetrating injuries to the thorax, abdomen, neck, or cranial cavity
High risk patients who require admission
Significant burns, suspected air embolism, radiation or WP contamination, abnormal vital signs, abnormal lung examination findings, clinical or radiographic evidence of pulmonary contusion or pneumothorax abdominal pain vomiting evidence of renal contusion or hypoxia penetrating injuries to the thorax abdomen neck or cranial cavity

42. Selected References
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DePalma RG, Burris DG, Champion HR, Hodgson MJ. Blast Injuries. N Engl J Med 2005; 352:
Hogan DE, Waeckerle JF, Dire DJ, Lillebridge ST. Emergency department impact of the Oklahoma City terrorist bombing. Ann Emerg Med 1999; 34:160-7.
Karmy-Jones R, Kissinger D, et. al. Bombing related injuries. Mil Med 1994;159:536-9.
Lavanos E. Blast Injuries. (Accessed September 21, 2005, at
Wightman JM, Gladish SL. Explosions and blast injuries: a primer for clinicians. Atlanta: Centers for Disease Control and Prevention. (Accessed September 21, 2005, at