Neurology · Topic 6 of 22
Traumatic Brain Injury
Neurology · neurotrauma
Traumatic Brain Injury
Prevent the second injury: no hypotension, no hypoxia, treat ICP above 22 mmHg with CPP 60–70, and reverse anticoagulants at once.
Key numbers
GCS grades TBI: severe is 3–8GCS ≤ 8 = severe
Keep SBP at least 100–110 mmHgSBP ≥ 100–110 mmHg
Keep SpO₂ ≥ 94% and PaCO₂ 35–45SpO₂ ≥ 94%
Treat ICP above 22; keep CPP 60–70ICP > 22 · CPP 60–70
Seizure prophylaxis for 7 days only7 days
01 · DoKeep SBP at least 100–110 mmHg
Avoid hypotension: target SBP ≥ 110 mmHg for ages 15–49 or over 70 and ≥ 100 mmHg for ages 50–69; never accept SBP below 90 mmHg — a single hypotensive episode doubles mortality.
02 · The numberTreat ICP above 22; keep CPP 60–70
In severe TBI with an ICP monitor, treat ICP above 22 mmHg and target CPP (MAP − ICP) 60–70 mmHg; avoid aggressively pushing CPP above 70 with fluids and pressors (ARDS risk).
03 · Defined byGCS grades TBI: severe is 3–8
TBI severity is graded by Glasgow Coma Scale after resuscitation: mild 13–15, moderate 9–12, severe 3–8. Score before sedatives or paralytics whenever possible, with pupils, and repeat serially.
01
Presentation
What you'll seeEpidural hematoma: lucid interval, lens-shapedEpidural hematoma is usually arterial (middle meningeal artery torn by a temporal bone fracture): a lucid interval, then rapid decline; CT shows a lens-shaped bleed that does not cross sutures. Large ones need surgery.
Subdural hematoma: crescent from bridging veinsAcute subdural hematoma comes from torn bridging or cortical veins, often with underlying contusion; CT shows a crescent-shaped bleed that crosses suture lines. Mortality is high when compression and swelling coexist.
02
Diagnosis & monitoring
Work-upKeep SpO₂ ≥ 94% and PaCO₂ 35–45 must knowAvoid hypoxia and hypo- or hypercarbia: keep SpO₂ ≥ 94%, PaO₂ 80–100 mmHg (avoid hyperoxia) and PaCO₂ 35–45 mmHg with end-tidal CO₂ monitoring when ICP is not elevated.
ICP monitor: GCS 3–8 with abnormal CTMonitor ICP in salvageable severe TBI (GCS 3–8 after resuscitation) with an abnormal CT, or a normal CT plus two of: age over 40, motor posturing, SBP below 90 mmHg.
03
Do right now
In this orderFirst moves
1
→Intubate severe TBI by rapid sequence
2
→Keep SpO₂ ≥ 94% and PaCO₂ 35–45SpO₂ ≥ 94%
3
→Keep SBP at least 100–110 mmHgSBP ≥ 100–110 mmHg
4
→Reverse anticoagulants immediately with 4F-PCC
5
Midline shift > 5 mm: emergent surgeryshift > 5 mm
Why each step
Intubate severe TBI by rapid sequenceSevere TBI (GCS 3–8) needs ICU care and orotracheal rapid sequence intubation with spine precautions; give sedation and analgesia before the paralytic and avoid nasotracheal intubation, which raises ICP.
Keep SpO₂ ≥ 94% and PaCO₂ 35–45Avoid hypoxia and hypo- or hypercarbia: keep SpO₂ ≥ 94%, PaO₂ 80–100 mmHg (avoid hyperoxia) and PaCO₂ 35–45 mmHg with end-tidal CO₂ monitoring when ICP is not elevated.
Keep SBP at least 100–110 mmHgAvoid hypotension: target SBP ≥ 110 mmHg for ages 15–49 or over 70 and ≥ 100 mmHg for ages 50–69; never accept SBP below 90 mmHg — a single hypotensive episode doubles mortality.
Reverse anticoagulants immediately with 4F-PCCReverse anticoagulation at once in TBI with bleeding: warfarin — 4-factor PCC plus IV vitamin K 2.5–10 mg (goal INR ≤ 1.4); dabigatran — idarucizumab 5 g IV; apixaban or rivaroxaban — 4F-PCC.
Midline shift > 5 mm: emergent surgeryGet an urgent noncontrast head CT and early neurosurgical consult; midline shift over 5 mm, compressed basal cisterns or a worsening exam call for emergent hematoma evacuation.
04
Management
OrdersSeizure prophylaxis for 7 days onlyFor high-risk TBI, phenytoin or levetiracetam for 7 days lowers early post-traumatic seizures; do not continue beyond 7 days (no effect on late seizures) and do not use valproate.
Mannitol or hypertonic saline for raised ICPFor raised ICP or herniation, give mannitol 0.25–1 g/kg IV or hypertonic saline boluses; stop escalating at serum sodium 155 mEq/L or osmolality 320 mOsm/kg.
Head of bed 30°, head midlineBasic ICP care: elevate the head of the bed 30°, keep the head midline and the cervical collar loose to aid venous drainage, provide sedation and analgesia, and keep sodium normal.
No platelets for antiplatelet TBI without surgeryDo not give platelet transfusion or desmopressin for TBI on antiplatelet drugs unless a neurosurgical procedure is needed; then consider one apheresis platelet unit and desmopressin 0.4 mcg/kg IV.
Start LMWH once repeat CT is stableStart pharmacologic VTE prophylaxis (LMWH preferred, e.g., enoxaparin 30 mg every 12 h) within 24 hours for low-risk and 24–48 hours for moderate- or high-risk nonoperative TBI, once repeat CT is stable.
05
Red flags & don'ts
Avoid harmNo corticosteroids in TBI avoidCorticosteroids do not lower ICP or improve outcome in TBI; high-dose methylprednisolone increased mortality (CRASH trial) and is contraindicated.
No prolonged prophylactic hyperventilation avoidProlonged prophylactic hyperventilation to PaCO₂ ≤ 25 mmHg is not recommended — vasoconstriction causes ischemia; brief hyperventilation is only a bridge for herniation or refractory ICP, avoided in the first 24 hours.
06
Epidural or subdural hematoma?
Commonly confused| Bleeding source | Arterial — usually middle meningeal artery |
|---|---|
| CT shape | Lens-shaped (lenticular), does not cross sutures |
| Associated injury | Temporal bone fracture |
| Classic course | Lucid interval, then rapid decline |
07
More detail
ReferenceShow 7 reference facts
Avoid hypotonic fluids (especially D5W) in TBI: free water worsens cerebral edema and ICP. Resuscitate with isotonic crystalloid or blood, and avoid hyponatremia, hyperthermia and hyperglycemia.
Early (within 2.5 hours), short-term (48 hours) prophylactic hypothermia is not recommended for diffuse TBI; target normothermia.
Refractory intracranial hypertension: decompressive craniectomy (a large frontotemporoparietal flap, at least 12 × 15 cm) or high-dose barbiturate coma once hemodynamically stable; neither is used prophylactically.
Basilar skull fracture signs: CSF rhinorrhea or otorrhea, hemotympanum, mastoid ecchymosis (Battle sign) and periorbital ecchymosis (raccoon eyes).
Suspect chronic subdural hematoma in older adults on antiplatelets or anticoagulants, in brain atrophy or alcohol use disorder with unexplained confusion — even without a remembered fall; CT shows a hypodense collection.
Diffuse axonal injury follows rotational shear forces: prolonged coma with an initially near-normal CT; MRI shows microhemorrhages in the corpus callosum, deep white matter and brainstem.
Reach full basal caloric replacement by day 5 and at most day 7 after severe TBI; transgastric jejunal feeding lowers ventilator-associated pneumonia.
One episode of hypotension doubles TBI mortality — the brain you save is the one you keep perfused and oxygenated.
Sources · Merck Manual Professional — Traumatic Brain Injury (TBI) (reviewed Oct 2024, updated Feb 2025) · Brain Trauma Foundation — Guidelines for the Management of Severe TBI, 4th Edition (Carney N et al. Neurosurgery 2017;80:6–15), recommendation index · American College of Surgeons — Best Practices Guidelines: The Management of Traumatic Brain Injury (ACS TQIP, 2024) · UMEM Educational Pearls (Univ. of Maryland) — Andexxa Withdrawn from US Market (Feb 2026; cites FDA Safety Communication Dec 18, 2025) · Starter sheet built from the verified AGACNP fact map (facts reviewed 2026-10-15).