Head trauma and the resulting brain injuries are one of the leading causes of death and disability in the industrialized world. In the United States, more than 50,000 people die every year as a result of traumatic brain injury. Furthermore, it is estimated that a head injury occurs every seven seconds, and hospital emergency rooms treat 1 million people for brain injuries every year. Currently about 5.3 million Americans — a little more than 2 percent of the U.S. population — live with disabilities resulting from such injuries.
Traumatic brain injury may occur at any age, but the peak incidence is among people between the ages of 15 and 24. Men are affected three to four times more often than women. Motor vehicle accidents are the leading cause, accounting for approximately 50 percent of all cases. Falls produce the most brain injuries in people older than 60 and younger than 5. Other causes include violent assault and firearms misuse. It has been estimated that after one brain injury, the risk of a second injury is three times greater, and that after a second injury, the risk of a third is eight times greater.
There are many head injury symptoms, ranging in seriousness. Minor injuries will cause mild or no symptoms, while severe injuries will cause major derangement of function. The most common symptom of brain injury after head trauma is a disturbance of consciousness; some people remain awake, but others are confused, disoriented, or unconscious. Headache, nausea, and vomiting are other common symptoms.
Anyone who sustains a head injury should be examined by a physician. Symptoms of brain trauma can be initially subtle, seemingly unrelated to the head, and not immediately apparent. A person who has sustained a serious head injury should not be manipulated or moved by people who are not trained to do so, because this may aggravate an injury.
Diagnosing Brain Trauma
The first thing doctors do when assessing a head injury is determine whether the person is in imminent danger of death. Once the person’s vital functions are stabilized, physicians examine the individual from a neurological perspective, checking:
- level of consciousness
- function of the cranial nerves (through pupillary responses to light, eye movements, and facial symmetry)
- motor function (strength, symmetry, and any abnormality of movements)
- breathing rate and pattern (linked to brain stem function)
- deep tendon reflexes, such as the knee jerk
- sensory function, such as response to a pinprick
- external signs of trauma, fracture, deformity, and bruising in the head and neck
Each of these parts of the physical exam will give a physician clues about the extent and location of any brain injury.
Doctors also need to know about the person’s behavior before, during, and after the injury. All of these points yield clues about what might have happened and how best to treat the person. Family members or people who witnessed the accident can usually provide helpful information. They can help medical professionals provide the best care possible by taking note of certain symptoms:
- unusual sleepiness or difficulty awakening
- mental confusion
- vomiting that continues or worsens
- restlessness or agitation that continues or worsens
- stiff neck
- unequal pupil size or peculiar eye movements
- inability to move arms and legs on either side
- clear or bloody drainage from the ears or nose
- bruising around the eyes or behind the ears
- difficulty breathing
This is a partial list.
Physicians can use a variety of radiological tests to assess a person with head trauma. Most hospital emergency departments can now do computed tomography (CT) scans. CT provides more information, and is excellent for diagnosing skull fractures, bleeding, or other important lesions in the brain. CT also helps doctors follow people with head trauma as they recover. Magnetic resonance imaging (MRI) currently has little involvement in diagnosing and treating an emergency, but once a person’s condition is stable an MRI may provide useful information that a CT cannot, such as evidence of white matter damage.
Different types of injuries require particular treatments. Surgery is needed to remove blood or foreign material, or to reconstruct parts of the skull. Very often brain trauma causes tissue to swell against the inflexible bone. In these cases, a neurosurgeon may relieve the pressure inside the skull by placing a ventriculostomy drain that removes cerebrospinal fluid. If the swelling is massive, a neurosurgeon may remove a piece of the skull so that the brain has room to expand; the surgeon keeps and reimplants the bone after the swelling has gone down significantly. Often during these procedures, the surgeon places a small pressure valve inside the skull to measure pressure on a moment-to-moment basis.
Most nonsurgical management of brain trauma involves close monitoring, often in an intensive care unit, to prevent further injury. Physicians will conduct further neurological exams in order to assess whether the person is improving or worsening. Doctors have no “miracle drug” to prevent nerve injury or improve brain function immediately after trauma, but they can use medication to modify a person’s blood pressure, optimize the delivery of oxygen to the brain tissue, and prevent further brain swelling.
From the Dana Foundation. Used with permission. www.dana.org.