A blast injury victim is examined after a high-order explosive detonation in an enclosed space. She has tympanic membrane perforation, pulmonary contusions, and intestinal haemorrhage, but no visible external wounds. These injuries are BEST classified as:

• A Secondary blast injuries from fragmentation projectiles
• B Tertiary blast injuries from the victim being displaced by the blast wind
• C Quaternary blast injuries from flash burns and inhalation
• D Primary blast injuries from the overpressure wave interacting with gas-filled structures ✓

Explanation

Primary blast injuries are caused exclusively by the supersonic overpressure (blast) wave and predominantly affect gas-containing structures: tympanic membranes (most sensitive, perforate at 5–7 psi), lungs (blast lung — alveolar haemorrhage, pneumothorax), and GI tract (intestinal haemorrhage). These injuries occur without any projectile impact. Secondary blast injuries are from flying fragments; tertiary are from being physically displaced (thrown); quaternary includes burns, crush, and inhalation. The enclosed space amplifies the blast wave by reflection, worsening primary injuries.

Reference: The Essentials of Forensic Medicine and Toxicology (Narayan Reddy), 34th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.