I recently reviewed a case of a person walking outside during fireworks who experienced something strike the top of his head. He could feel something solid stuck in his scalp and thought a piece of a firework had hit him. But then he noticed that people nearby were shooting guns into the air. He also noted a slight weakness and numbness in his upper extremity.

He rapidly proceeded to his local emergency department. Sure enough, physical exam and CT scan revealed a small caliber bullet partially embedded in the top of his skull, with a small contusion in the frontoparietal area. Neurosurgery removed the projectile without incident, and the dura was intact. His neurologic symptoms improved but did not fully disappear before discharge.

This whole situation made me curious. How big a problem is this? How dangerous are bullets fired in the air? The first paper I could find in the trauma literature dates back to 1994 in the Journal of Trauma. The authors presented a series of 118 patients struck by falling projectiles over 10 years. The majority of patients were struck in the head (77%), and the mortality was 32%!

An interesting case report described a male who was watching fireworks who presented to the ED with chest pain and dyspnea.

The terminal velocity of bullets varies based on their size and shape. It ranges from 200-300 ft/sec, or 140-200 mph! Although these numbers are lower than the initial muzzle velocity, they are quite high and comparable to the velocity of a high-powered pellet gun. But with a much heavier projectile. On exam, a penetrating injury was seen above the nipple on the left chest. The abdominal x-ray showed this:

He was taken for laparotomy, and injuries to the splenic hilum, stomach, and diaphragm were identified. Two ventricular injuries were also found and were successfully repaired.

Bottom line: Bullets fired into the air can reach high altitudes and attain high terminal velocities on their descent. The speeds involved can easily pierce bone (e.g., the cranium) and traverse multiple body cavities. Although this activity is universally illegal, it still occurs. Always be wary of this issue during public fireworks celebrations and large family celebrations. Perform a thorough exam of all the nooks and crannies so that these sometimes subtle injuries are identified quickly.

References:

• Spent bullets and their injuries: the result of firing weapons into the sky. J Trauma. 1994 Dec;37(6):1003-6. PMID: 7996596.
• Cardiac injury caused by a celebratory bullet. Ann Thorac Surg. 2007 Jan;83(1):283-4. doi: 10.1016/j.athoracsur.2006.04.046. PMID: 17184680.