Which mechanism of a lightning strike primarily damages air-containing structures in the body?

The primary mechanism through which a lightning strike causes damage to air-containing structures in the body, such as the lungs, is the rapid expansion of air. When lightning strikes, the intense heat generated can cause the air surrounding the current to expand dramatically and suddenly. This rapid expansion creates a shock wave that can rupture air-containing organs, especially in the case of the lungs.

The lung tissue can be severely affected, leading to conditions such as pneumothorax (collapsed lung) or other forms of airway injury due to the explosive force of the air expanding.

While direct contact with thermal energy can cause burns and injury to tissue, the specific damage to air-containing structures is primarily due to the shock wave from rapidly expanding air. Similarly, while electrical energy can cause various injuries, it is the physical mechanical effect of air expansion that predominantly impacts the structures containing air when it comes to lightning strikes. As for smooth muscle contraction, while electrical energy can indeed stimulate muscles, it does not specifically cause the type of damage associated with air-containing structures as does the rapid air expansion.