Cranial gunshot wounds
A cranial gunshot wound is a penetrating wound through the skull caused by a firearm. A wound in which the bullet enters the skull, but does not exit, is referred to as a penetrating wound. A wound in which the bullet enters and exits the skull, is referred to as a perforating wound. As a bullet passes through the brain, the bullet creates a hole 3-4 times larger than the original bullet diameter. The path of the bullet and its pressure wave cause the majority of the damage in the brain.
Cranial gunshot wounds are aggressively treated upon arrival to a hospital. 90% of the time, the victim of a cranial gunshot wound will die before arrival to the hospital. For victims that survive the initial encounter, up to 50% may die in the emergency room.
Once the patient’s blood pressure and oxygen levels are stabilized, a Computerized Tomography (CT) scan of the brain will provide an image of areas damaged from the gunshot wound. Damage can be caused from the bullet entry, its pathway, bullet fragmentation, and its exit. The caliber of the bullet, the weapon from which it was fired, as well as the distance between the gun and the victim, all play a role in the amount of damage caused in the patient.
If a hematoma (collection of clotted blood) is shown on the CT scan, an emergency craniotomy may be performed, where the skull is opened to remove the clotted blood. It is also common for swelling of the brain to occur, and a craniectomy procedure may be performed in which a portion of the skull is temporarily removed until the swelling decreases. Superificially accessible bullet fragments may be surgically removed, though deep fragments may be left behind, as surgical removal may cause more damage to the brain.
If a patient survives the initial gunshot wound, the path of the bullet determines the extent of injury. Outcome is worse for those with damage into the deep midline structures of the brain, or areas of the brainstem.
The patient will be most often be admitted to a critical care unit for several weeks after the trauma. After that, the extent and speed of recovery is dependent on the amount of injuries and the general health of the patient prior to the incident. Rehabilitation is often necessary to help regain some function, and most often, to adapt to permanent injuries. Recovery could take from several months to several years, with many patients never reaching their baseline health prior to the injury.
Jessica Siu and Justin F. Fraser, MD
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Wright DW, Merck LH. Chapter 254. Head Trauma in Adults and Children. In: Tintinalli JE, Stapczynski JS, Cline DM, Ma OJ, Cydulka RK, Meckler GD, eds. Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 7th ed. New York: McGraw-Hill; 2011. http://www.accessmedicine.com/content.aspx?aID=6388784. Accessed November 25, 2011.
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