Which category of blast injuries is characterized by injuries from the pressure wave affecting air-filled organs?

• A. Primary blast injuries
• B. Secondary blast injuries
• C. Tertiary blast injuries
• D. Quaternary blast injuries

Answer: (A)

The main idea is that the initial overpressure of an explosion primarily injures gas-filled spaces. The blast wave rapidly compresses and then expands air-filled organs, so structures like the lungs, ears, sinuses, and other gas-containing systems are especially vulnerable to barotrauma. In the lungs this can lead to alveolar rupture, pulmonary contusion, pneumothorax, or hemorrhage, while the tympanic membrane in the ear may rupture from the sudden pressure difference. This is what defines primary blast injuries. Other mechanisms cause different injury patterns—debris or shrapnel causing penetrating injuries (secondary), the body being thrown into objects (tertiary), or burns and inhalation injuries (quaternary)—but the hallmark of primary blast injury is the pressure-wave impact on air-filled organs.