CDC Expert Commentary: Four Critical Questions to Ask in the Evaluation of Adult Traumatic Brain Injury

Vikas Kapil, DO, MPH


October 18, 2010

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A 20-year-old patient arrives into the emergency department after a car crash and is complaining that he hit his head and has a headache.

  • Does this patient need a head CT [computed tomography] or MRI [magnetic resonance imaging]?

  • Can this patient be safely discharged from the emergency department?

If that scenario sounds familiar, it's likely that you're one of thousands of emergency department clinicians who have examined patients with a suspected TBI (traumatic brain injury) resulting from any number of events including falls, motor vehicle crashes, or a collision while playing sports.

Hello, I'm Dr. Vik Kapil, Associate Director of Science in the Division of Injury Response at the Centers for Disease Control and Prevention [CDC].

I'm pleased to speak with you today about mild TBI as part of the CDC Expert Commentary Series on Medscape.

So, how do you evaluate whether it is safe for your adult patient to go home?

What are the recommendations regarding mild TBI?

You can use the latest guideline on mild TBI for adults in the acute care setting developed by the Centers for Disease Control and Prevention, and the American College of Emergency Physicians.

The new guideline is intended for patients with nonpenetrating head trauma who arrive at the emergency department within 24 hours of injury; on initial evaluation have a GCS [Glascow Coma Scale] score of 14 or 15; and are age 16 or older.

The guideline presents you with 4 critical questions that you need to ask yourself in order to diagnose and treat patients with mild TBI. It also includes recommended courses of action for each question. For each of the 4 critical questions, the guideline provides recommendations for evaluation and management based on the best available evidence.

Following this clinical policy, the current recommendations are graded on a 3-tier scale. These levels are A, B, and C.

Level A recommendations are generally accepted principles for patient management that reflect a high degree of clinical certainty. Level B recommendations generally identify a particular strategy or range of management strategies that reflect moderate clinical certainty. And level C recommendations are based on preliminary, inconclusive evidence, or in the absence of any published literature, based on panel consensus.

You may wish to take notes as we walk you through each question and the corresponding recommendations. Since it's a lot to digest, stay tuned until the end of the podcast to learn where you can access additional information.

The first critical question to consider is: Which patients with mild TBI should have a noncontrast head CT scan in the emergency department?

The level A recommendation is to obtain a head CT in patients with loss of consciousness or post-traumatic amnesia if they are over the age of 60 or if they exhibit one or more of the following:

  • Headache;

  • Vomiting;

  • Intoxication from drugs or alcohol;

  • Deficits in short-term memory;

  • Physical evidence of trauma above the clavicle;

  • Post-traumatic seizure;

  • GCS score lower than 15;

  • Focal neurologic deficit; or

  • Coagulation abnormality.

The level B recommendation is to consider a noncontrast head CT in head trauma patients who have had no loss of consciousness or post-traumatic amnesia, if they are older than 65, or exhibit any of the following:

  • Focal neurologic deficit;

  • Vomiting;

  • Severe headache;

  • Physical signs of a basilar skull fracture;

  • GCS score lower than 15; or

  • Coagulation abnormality.

There is no level C recommendation.

Moving on to the second critical question: Would an MRI be just as effective as a noncontrast head CT in determining whether a particular patient has a significant TBI?

There is no specified recommended course of action for this question because there is no evidence to support the use of an MRI over a head CT for evaluation of TBI in acute care settings. You should identify the best course of action based on your evaluation of the patient and availability of diagnostic services at your hospital.

The third critical question for you to consider is: Do any brain-specific serum biomarkers predict the presence or severity of an acute TBI?

There are no level A or B recommendations.

Based on research efforts in Europe on TBI biomarkers, the level C recommendation is that you may consider omitting a CT scan in patients with mild TBI without significant extracranial injuries and a serum S-100-B level < 0.1 µg/L measured within 4 hours of injury.

However, you should note that this test has not been approved for clinical use in the United States, and therefore is generally not available in most clinical settings.

And now for the fourth and final critical question: If the noncontrast CT does not show evidence of intracranial injury in patients who have isolated mild TBI with a normal neurologic evaluation, can the patient be safely discharged from the emergency department?

There are no level A recommendations.

The level B recommendation is that you may discharge patients with isolated mild TBI who have negative head CT scans because they are at minimal risk for developing intracranial lesions.

And finally, the level C recommendation is to inform patients with mild TBI and their family members about postconcussive symptoms when they are discharged from the emergency department.

To view the mild TBI management guideline, instruction sheets, and wallet card for adult patients, visit or

Thank you for tuning in.

Web Resources

CDC Injury Prevention and Control: Traumatic Brain Injury

Heads Up to Clinicians

Concussion and Mild TBI

Vikas Kapil, DO, MPH, currently serves as the Associate Director for Science in the Division of Injury Response at the CDC's National Center for Injury Prevention and Control. Previously, he served as Senior Medical Officer and Chief of the Surveillance and Registries Branch in the Division of Health Studies at the Agency for Toxic Substances and Disease Registry (ATSDR).

He attended medical school at Michigan State University College of Osteopathic Medicine and received a Masters in Public Health (MPH) from the University of Michigan. He completed residency training in emergency medicine at POH Medical Center in Pontiac, Michigan, and in occupational and environmental medicine at the University of Michigan Medical Center. Dr. Kapil is board certified in emergency medicine and occupational/environmental medicine and holds licensure to practice in Georgia, North Carolina, and Ohio.


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