Primary blast injury

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.