Emergency Room Practices Part 1: Evaluating Patients with a Concussion
Emergency rooms in the United States see about 2.5 million patients with traumatic brain injury (TBI) each year. The majority of these encounters are for mild TBI (mTBI), more commonly known as concussion. Emergency physicians use guidelines established by the American College of Emergency Physicians (ACEP) to diagnose and treat patients. Like all national medical boards, the ACEP exists to ensure that patients across all hospitals receive uniform care and to ensure that the standard of care is in accordance with currently accepted best practices. In 2002, the ACEP established a policy for the evaluation and treatment of patients with mTBI. The most recent update to this policy was in 2008. The guidelines based on this policy are designed to identify patients who are most at risk for an intracranial injury that is not visible upon examination. According to the ACEP, these guidelines apply to:
“…patients with non-penetrating trauma to the head who present to the ED within 24 hours of injury, who have a Glasgow Coma Scale (GCS) score of 14 or 15 on initial evaluation in the ED, and are ≥ 16 years old.”
The Glasgow Coma Scale is an outcome metric administered to a patient immediately after a head injury. This assessment helps healthcare providers understand the severity of symptoms by testing a patient’s eye-opening, verbal, and motor responses. Lower scores indicate higher severity of injury: a score of 8 or less indicates a severe head injury; a score of 9-12 (or 13) is classified as a moderate head injury; and a score of 13 (or 14)-15 is classified as a mild head injury. Experts dispute whether a score of 13 should be classified as mild or moderate.
The ACEP explicitly states that the mTBI guidelines are NOT for use with patients with moderate or severe head injuries.
The guidelines consist of four critical questions that help emergency physicians make decisions about the best course of action to identify at-risk patients and to provide a consistent standard of care:
- Which patients with mild TBI should have a non-contrast head CT scan in the ED?
- Is there a role for head MRI over non-contrast CT in the ED evaluation of a patient with acute mild TBI?
- In patients with mild TBI, are brain-specific serum biomarkers predictive of an acute traumatic intracranial injury?
- Can a patient with an isolated mild TBI and a normal neurologic evaluation be safely discharged from the ED if a non-contrast head CT scan shows no evidence of intracranial injury?
In response to the questions, the ACEP provides three tiers of recommendations (when available) that differ in their degree of “clinical certainty.” Level A recommendations are based on generally accepted medical principles which can be applied to most patients; Level B recommendations are based on moderate clinical certainty and may be applied in certain cases; and Level C recommendations are based on preliminary or conflicting evidence. Not all questions have standard recommendations. For instance, the ACEP states that level A, B, and C recommendations are not specified for Question 2, indicating that there is no evidence that suggests that an MRI is a better diagnostic tool than is a non-contrast CT scan.
Level A recommendations — those that are backed by evidence and which are recommended by the ACEP for use with most patients — are only available for Question 1, and the recommendation states that a non-contrast CT scan is only recommended patients for who have experienced loss of consciousness or post-traumatic amnesia AND are experiencing at least one additional symptom, such as headache, fatigue, or vomiting. In other words, of the four critical questions that emergency physicians ask when treating a patient with mTBI, only one has a recommended course of action that is backed by evidence.
For most patients with mTBI, the greatest risk comes at discharge, and Question 4 acknowledges this risk. ACEP does not provide level A recommendations for determining the risk associated with discharging patients who have no neurological evidence of injury, but there is moderate clinical certainty (level B) that patients can be safely discharged if they have had a CT scan that shows no evidence of injury. Theoretically, however, patient that do not meet the criteria for level A recommendations in Question 1 will not receive a CT scan. Level C recommendations are that such patients should be discharged with information about post-concussive symptoms.