Primary Blast Injury
Definition
Injury caused directly by the overpressure (blast) wave. Preferentially affects gas-containing organs (lungs, tympanic membranes, bowel). Blast lung (alveolar haemorrhage, barotrauma) is the most lethal primary mechanism. No external wound is visible. Diagnosed at autopsy by pulmonary contusion pattern, tympanic membrane perforation, and bowel wall haemorrhage.
- Cause
- The overpressure blast wave itself
- Organs affected
- Gas-containing organs: lungs, ears, bowel
- Most lethal form
- Blast lung (alveolar haemorrhage, barotrauma)
- External wound
- None visible
- Autopsy findings
- Pulmonary contusion, tympanic perforation, bowel haemorrhage
Common questions
Why can primary blast injury be fatal without any visible external wound?+
The overpressure wave transmits its force through the body at interfaces between tissues of different density, such as air-filled alveoli against blood-filled capillaries, causing internal tearing and haemorrhage while the skin surface remains intact.
How is primary blast injury distinguished from other blast injury mechanisms at autopsy?+
It is identified by the absence of penetrating fragment wounds or blunt structural trauma, combined with characteristic internal findings such as a pulmonary contusion pattern and tympanic membrane rupture, which point to overpressure rather than fragmentation or displacement as the injury mechanism.
Related terms
- Blast Lung Injury
- Bilateral pulmonary contusion and alveolar tear from primary blast overpressure. The most lethal primary blast mechanism. Characterised at autopsy by bilateral 'butterfly'...
- Quaternary Blast Injury
- All blast-related injury not in primary/secondary/tertiary classes: burns (flash fireball + secondary fire), crush (structural collapse), and inhalation injury (CO, HCN, particulate)....
- Secondary Blast Injury
- Penetrating injury from fragments: device casing metal, pre-formed projectiles (nails, bolts, BBs), or environmental debris accelerated by the blast wave. The most...
- STANAG 2920
- NATO Standardization Agreement 2920, defining the fragmentation injury threshold for ballistic protection standards. Relevant in blast forensic pathology for relating fragment mass...
- Tertiary Blast Injury
- Blunt-force injury caused by physical displacement of the victim's body by the blast wind, followed by impact against surfaces. Morphologically identical to...
- Tympanic Membrane Perforation (TMP)
- Rupture of the eardrum by blast overpressure, occurring at 35-103 kPa, well below the threshold for blast lung injury. The most sensitive...