Blast InjuryBlast Injury

HARRT 2004HARRT 2004

PRIMARY BLAST INJURYPRIMARY BLAST INJURY Unique to HE explosionsUnique to HE explosions Damage sustained as a Damage sustained as a

direct result of the blast direct result of the blast wavewave

Air-containing structures Air-containing structures are the most susceptible:are the most susceptible:

LungsLungs G.I. TractG.I. Tract Ears (tympanic membranes)Ears (tympanic membranes)

PRIMARY BLAST INJURYPRIMARY BLAST INJURY Damage occurs in 3 ways:Damage occurs in 3 ways:

Spalling: Spalling: Pressure wave Pressure wave moving from an area of moving from an area of high density to one of high density to one of lower density. lower density. Results in turbulence Results in turbulence

at the interface at the interface between the 2 areas between the 2 areas and a shattering of and a shattering of tissue at the border.tissue at the border.

Implosion:Implosion: Compression Compression of pockets of gas within of pockets of gas within areas of the body causing areas of the body causing them to rebound to a them to rebound to a greater volume as the greater volume as the wave passeswave passes

Acceleration/Acceleration/DecelerationDeceleration of different of different tissues at different rates tissues at different rates and speedsand speeds

PRIMARY BLAST PRIMARY BLAST INJURY:PULMONARY INJURY:PULMONARY

BAROTRAUMABAROTRAUMA Most common type of Most common type of

fatal blast injury.fatal blast injury. Generalized alveolar Generalized alveolar

damage due to spalling damage due to spalling effect:effect:

HemorrhageHemorrhage EdemaEdema Parenchymal/pleural Parenchymal/pleural

lacerationslacerations A-V fistulasA-V fistulas Acute Gas Embolism (AGE)Acute Gas Embolism (AGE) ARDSARDS Pulmonary contusionsPulmonary contusions

SECONDARY BLAST SECONDARY BLAST INJURYINJURY

Both HE and LE ExplosionsBoth HE and LE Explosions Damage sustained by the impact of debris energized by Damage sustained by the impact of debris energized by

the blast.the blast. Speeds > 1500 mph. Speeds > 1500 mph. One’s thumb in another’s neck.One’s thumb in another’s neck.

Due to blast winds.Due to blast winds. Both blunt and penetrating trauma.Both blunt and penetrating trauma. Responsible for majority of casualties.Responsible for majority of casualties.

e.g. Oklahoma City: e.g. Oklahoma City: wounds due to wounds due to glass shards. glass shards.

Pipe bombsPipe bombs

PHYSICAL EXAMPHYSICAL EXAM

A,B,CsA,B,Cs LUNGSLUNGS

Contusion, pneumothoraxContusion, pneumothorax DyspneaDyspnea Chest painChest pain HemoptysisHemoptysis Rales, rhonchiRales, rhonchi CyanosisCyanosis Respiratory S&S may occur later.Respiratory S&S may occur later.

PHYSICAL EXAMPHYSICAL EXAM G.I. TRACTG.I. TRACT

Principally colon & Principally colon & stomach.stomach.

OccultOccult May require repeat May require repeat

examsexams Pain, nausea, vomiting, Pain, nausea, vomiting,

rectal bleeding, rectal bleeding, testicular pain.testicular pain.

Especially in closed-Especially in closed-space/underwater blastsspace/underwater blasts

Leibovici, ‘99: No such Leibovici, ‘99: No such injuries found in open-air injuries found in open-air bombings in his series.bombings in his series.