Traumatic brain injury
Stem
A 34-year-old man, 85 kg, was thrown from a motorcycle. His GCS is 7, his left pupil is 6 mm and sluggish, and CT shows a left acute subdural hematoma with 9 mm of midline shift. He is in a cervical collar, with no other major injuries on a negative FAST. Blood pressure is 104/62, heart rate 108, SpO2 93% on a non-rebreather. He is coming straight to the OR for craniotomy.
Question
How will you manage his anesthetic from induction through evacuation?
Ideal answer
HeadlineHerniating subdural: I prevent secondary injury, because hypotension and hypoxia kill brain the crash spared. Norepinephrine or phenylephrine infusion now: at 34, systolic at or above 110.1
- Arterial line without delay; video laryngoscope, suction ready, for beat-to-beat pressure and a full-stomach airway.
- Preoxygenate; rapid sequence with in-line stabilization, for a full stomach and presumed spine injury:2 reduced propofol plus ketamine 0.6–1 mg/kg to protect his pressure,2 fentanyl to blunt laryngoscopy, rocuronium 1.2 mg/kg, about 100 mg.
- Blown pupil means herniation: mannitol 0.25–1 g/kg (up to 85 g) or hypertonic saline; brief hyperventilation until the dura is open, then normal PaCO2.1
- Propofol or low-dose volatile; CPP 60–70 mmHg,1 glucose 110–180, temperature 36–37 °C.2
- Early gas, hemoglobin and coagulation, because brain injury releases tissue factor and causes coagulopathy; no steroids.
Breaking down the answer
- Age-specific targets — systolic ≥100 mmHg at 50–69 years and ≥110 mmHg at 15–49 or over 70.1 Starting a pressor before induction shows anticipation, not reaction.
- Ketamine is no longer forbidden — in a ventilated, hypotensive patient its sympathetic support protects perfusion pressure; with a hypnotic, the dose is considered safe.2
- Succinylcholine is acceptable — up to 1 mg/kg causes only a slight, transient rise in ICP; I choose it if I worry about the airway, rocuronium otherwise.2
- Hyperventilation is a bridge — prolonged prophylactic hyperventilation to 25 mmHg or less causes ischemia and is not recommended, and it is avoided in the first 24 hours when flow is often critically low; I use it only for active herniation.1
- Do not overshoot CPP — fluids and pressors pushed above 70 mmHg raise the risk of respiratory failure.1
- Why no steroids — high-dose methylprednisolone increased mortality; early prophylactic hypothermia is not recommended either.1
Follow-up question
The bone flap comes off and the surgeon opens the dura. Within a minute the blood pressure falls from 128/76 to 68/40 and the heart rate rises to 130. What is happening, and what do you do?
Follow-up answer
HeadlineDecompression hypotension: the Cushing response vanished with the ICP and unmasked hypovolemia. I tell the surgeon and ask about sinus or dural bleeding.
I increase the pressor, give a bolus of crystalloid and blood through warmed lines, lighten the anesthetic, and send hemoglobin, gas, ionized calcium and coagulation; I treat coagulopathy to platelets above 100,000 and fibrinogen above 200 mg/dL.2 If he does not respond, I look for a missed bleed, such as an abdomen that bled since the FAST, or a pneumothorax. I reassess pressure, perfusion pressure and pupils, keeping the systolic at or above 110.1
Pitfalls that cost points
- Accepting a systolic of 90 mmHg as "fine" in a 34-year-old with a brain injury.
- Giving dexamethasone because it works for tumors.
- Hyperventilating to a PaCO2 of 25 for the whole case.
Rapid-fire
Q: At what ICP does the guideline recommend treatment? A: Above 22 mmHg.1
Q: Does he need seizure prophylaxis? A: Phenytoin is recommended to reduce early seizures within 7 days; it does not prevent late seizures.1
Q: Mannitol or hypertonic saline? A: Both lower ICP; mannitol diureses and can cause hypovolemia, so I favor hypertonic saline when he is hypotensive.2
Q: Who needs an ICP monitor? A: Salvageable patients with GCS 3–8 after resuscitation and an abnormal CT.1
Q: What size decompressive craniectomy does the guideline favor? A: A large frontotemporoparietal flap, at least 12 by 15 cm.1
Numbers to know
| Item | Value |
|---|---|
| SBP, age 15–49 or >70 | ≥110 mmHg1 |
| SBP, age 50–69 | ≥100 mmHg1 |
| ICP treatment threshold | >22 mmHg1 |
| CPP target | 60–70 mmHg1 |
| Mannitol | 0.25–1 g/kg1 |
| Glucose | 110–180 mg/dL2 |
| Ketamine at induction | 0.6–1 mg/kg, 50 to 85 mg for him2 |
Links
- Raised intracranial pressure: evaluation and reduction, Trauma: initial management and damage control, Airway management with cervical spine injury, Rapid sequence induction and full stomach, Seizure disorders
- Brain Trauma Foundation Guidelines for the Management of Severe TBI, 4th edition (2016)
Sources
- 1.Guidelines for the Management of Severe Traumatic Brain Injury, 4th Edition (Executive Summary) · Brain Trauma Foundation, 2016 · braintrauma.orgTrauma-specific; blood pressure, ICP, CPP, hyperventilation, mannitol, steroid, seizure prophylaxis and hypothermia recommendations.
- 2.Anesthesia for patients with traumatic brain injury · Colombian Journal of Anesthesiology (Mejia Mantilla, Gonzalez Arboleda), 2015 · elsevier.esNarrative review; induction agents, succinylcholine, osmotherapy, glucose, temperature and coagulation targets.
Facts on this page were checked against these sources on Oct 15, 2026. Guidelines change; confirm doses against current institutional protocols.