A 24-year-old male was a nonhelmeted motorcyclist hit by a car. EMS arrived to find him with labored breathing and intubated him. His GCS was 6 prior to intubation: eyes did not open, incomprehensible speech, and withdrawal of all extremities to painful stimulation. On presentation to the ED, he underwent a trauma evaluation and had nondisplaced parietal bone fracture, mastoid fracture, and multiple noncongruent rib fractures. His head CT demonstrated small bifrontal and temporal lobe intraparenchymal hemorrhages, a small amount of bilateral frontal SAH, and a 2 mm right frontal subdural hemorrhage. He was admitted to the neurologic intensive care unit (ICU) where a bolt was placed, which demonstrated a normal ICP. He continued in the same comatose state for 12 hours with a repeat head CT that was stable.
What is the next best test?a. MRI of the brain with imaging including gradient echo sequence (GRE)
Correct Answer: B
Nonconvulsive status epilepticus is a common (22%) finding in severe TBI. Those who have prolonged, unexplained depressed level of consciousness within the ICU should undergo prolonged EEG monitoring for evaluation of possible nonconvulsive seizures and status epilepticus. In comatose patients, it frequently takes 24 hours of monitoring to capture the first seizure. Further prolonged EEG monitoring can still capture further electrographic seizures; however, there are no recommendations regarding the length of EEG monitoring. Patient’s multicompartment contusions will make him at higher risk of seizures. The other answers may be appropriate in certain clinical settings but are not the best answers. GRE is a specific MRI sequence that evaluates for iron deposition and is related to the extent of diffuse axonal injury, which is overall helpful in guiding our outcome prognostication. Cerebral vasospasm can occur with traumatic SAH, within 48 hours of the initial head injury. The hyperacuity of the patient’s current presentation is likely to exclude vasospasm. There is no clear need to start hyperosmolar therapy; patient’s bolt shows normal ICPs and his repeat head CT that was stable.