11.1 Traumatic Brain Injury
Key Takeaways
- Report Glasgow Coma Scale as three numbers and trend the motor score; a two-point motor drop after packaging is a new mass lesion or a new secondary insult until proven otherwise.
- Epidural hematoma is the lucid-interval collapse; subdural is often bridging veins in older or anticoagulated patients; traumatic SAH marks significant injury; DAI is a terrible exam with a relatively quiet CT.
- Cushing triad, a new blown pupil, and posturing are herniation now—oxygenate, restore blood pressure, raise the head if you can, and give protocol osmotherapy.
- A single hypoxic or hypotensive hit worsens outcome; Dalton's law makes cabin hypoxia a planned insult unless you raise FiO2 or lower the cabin.
- Target ETCO2 35–40 mm Hg, not prophylactic hyperventilation; HTS versus mannitol follows program protocol; seizure prophylaxis is not routine for every concussion; destination is a neurotrauma center.
Traumatic brain injury in flight is a race against the next preventable insult, not a race to name the bleed after you land. Domain 3.B of the August 2026 Board of Certification for Emergency Nursing (BCEN) Certified Flight Registered Nurse (CFRN) outline tests traumatic brain injury (TBI) because cabin hypoxia, one hypotensive dip, and a delayed neurosurgical destination can erase a technically perfect scene intubation. Classify severity, recognize the bleed pattern from the story, catch herniation early, protect the airway with the cervical spine, and fly to a neurotrauma center.
Severity by Glasgow Coma Scale
Report the parts, then trend motor
The Glasgow Coma Scale (GCS) is three numbers: eye (E1–4), verbal (V1–5), and motor (M1–6). Report the parts, not only the sum. A GCS of 8 that is E1 V2 M5 is not the same patient as E2 V1 M5. Motor carries the most prognostic weight. A two-point motor drop after the collar clicks or the litter locks is a new mass lesion or a new secondary insult until you prove sedation, seizure, or hypoxia.
| Severity | GCS sum | Flight meaning |
|---|---|---|
| Mild | 13–15 | Can still hide an epidural; a lucid interval is not stable |
| Moderate | 9–12 | If the trend is down, secure the airway on the ramp |
| Severe | 3–8 | Definitive airway, prevent secondary insults, neurotrauma destination |
A sending-note GCS is a snapshot. Recheck after the collar, after lift, and after every cabin-altitude change. Intoxication, seizure, and hypoxia all drop the score—treat the cause and rescore.
Bleed patterns you recognize without the scanner
You will not read the computed tomography (CT) in a vibrating cabin. You will recognize the mechanism.
Epidural hematoma (EDH) is often arterial, classically the middle meningeal artery under a temporal skull fracture. The story is a blow, a brief loss of consciousness, a lucid interval, then sudden coma and an ipsilateral blown pupil. These patients can talk on the ramp and herniate ten minutes into cruise.
Subdural hematoma (SDH) is usually torn bridging veins. The collection is crescent-shaped and crosses sutures. Older adults, alcohol use, and anticoagulants are the risk cluster. Acute high-energy SDH can kill as fast as an epidural. Chronic SDH presents days later with a waxing exam.
Traumatic subarachnoid hemorrhage (SAH) is blood in the cisterns and sulci after trauma. It is not aneurysmal thunderclap SAH, but it still marks significant brain injury and raises early seizure risk.
Diffuse axonal injury (DAI) is shear from acceleration–deceleration or rotation—ejection, rollover, pedestrian struck. The GCS is terrible. Early CT can look almost normal or show only small petechial hemorrhages at the gray–white junction, corpus callosum, or brainstem. DAI is not a burr-hole disease. It is a secondary-insult disease.
Herniation you cannot miss
Uncal herniation compresses cranial nerve III against the tentorium: ipsilateral dilated (blown) pupil, then contralateral hemiparesis. Central herniation gives small, then midposition pupils and a progressive motor fade. Tonsillar herniation crowds the foramen magnum and produces apnea.
Cushing triad—hypertension, bradycardia, and irregular respirations—is late. Do not wait for all three. A new unilaterally blown pupil plus a falling motor score is herniation now. Decorticate (flexor) posturing is usually a higher lesion than decerebrate (extensor). Treat either immediately: oxygenate, restore blood pressure, sit the head up if you can, and give protocol osmotherapy.
Airway with the cervical spine, then do not add a second hit
Assume an unstable cervical (C-)spine with every significant blunt TBI until a trauma center clears it. Open the collar with manual in-line stabilization (MILS) for the look, then close it. Blood, vomit, trismus, and a rigid collar make this a predicted difficult airway—stage two suctions, video laryngoscopy, and an open surgical kit on the ground.
Avoid hypoxia and hypotension. A single systolic blood pressure under 90 mm Hg or a single desaturation is associated with worse outcome—classic Brain Trauma Foundation (BTF) teaching. Dalton's law drops the partial pressure of inspired oxygen (PIO2) as barometric pressure falls even if fraction of inspired oxygen (FiO2) is unchanged, so raise FiO2 or request a lower cabin. Known pneumocephalus can expand under Boyle's law on climb.
Head of bed (HOB) 30 degrees if there is no contraindication—unstable shock that needs a flatter ride, some spine packages, or a loading geometry you cannot change. Keep the neck neutral. Do not cinch tape across the internal jugular veins.
Target end-tidal carbon dioxide (ETCO2) 35–40 mm Hg. Prophylactic hyperventilation is harmful because hypocapnia vasoconstricts the brain. Brief hyperventilation toward 30–35 mm Hg is only a bridge for active herniation, then return to 35–40.
Hypertonic saline (HTS) and mannitol are both osmotic options. Mannitol can drop blood pressure in a bleeding patient; HTS supports volume. Follow your program dose.
Seizure prophylaxis is not routine for every concussion. Early (about seven-day) prophylaxis with levetiracetam or phenytoin is considered for severe TBI to reduce early post-traumatic seizures. A GCS 15 concussion does not get automatic loading.
Destination is a neurotrauma center—neurosurgery, CT, and an intensive-care unit (ICU) that can manage intracranial pressure (ICP). A closer hospital without a neurosurgeon is the wrong pad if the patient is herniating.
- Report GCS as three numbers and trend motor first.
- Treat a lucid interval as an epidural until imaging says otherwise.
- Prevent one hypoxic or hypotensive hit; Dalton's law is that hit on climb.
- Keep ETCO2 35–40 unless you are briefly treating herniation.
- Fly to a neurosurgical trauma center.
A flight nurse is packaging a helmeted scene patient with a temporal scalp laceration. Blood pressure is 88/54 mm Hg and saturation is 89 percent on a nonrebreather just before lift. Which statement best describes the neurologic risk of those two numbers?
After a ground intubation for a GCS of E1 V2 M4, there is no blown pupil and no posturing. Which ventilation target is correct for the flight?
A patient talks and follows commands after a baseball-bat blow to the left temple, then becomes unresponsive in cruise with a newly dilated left pupil. What is the best interpretation and destination?