Awake craniotomy
Stem
A 36-year-old right-handed woman, 68 kg, has a low-grade glioma in the left inferior frontal gyrus abutting Broca's area. She is scheduled for awake craniotomy with cortical language mapping and resection, head in pins. She has had three focal seizures this year, controlled on levetiracetam. She is anxious but motivated, speaks fluently, has a BMI of 26, no sleep apnea, and a Mallampati 2 airway.
Question
How will you plan and conduct the anesthetic for her awake craniotomy?
Ideal answer
HeadlineA comfortable, still, cooperative patient awake for language mapping, with an airway I can rescue instantly: monitored sedation over a complete scalp block.
- Select and prepare her. She must cooperate and be emotionally ready; I screen for sleep apnea, persistent cough or significant dysphasia,1,2 explain phases, agree mapping with surgeon and neuropsychologist.
- Levetiracetam, plus a bolus before incision, because mapping provokes seizures.1
- Monitored sedation with a natural airway, so she can talk: dexmedetomidine, small titrated propofol and low-dose remifentanil for pinning and opening, stopped or minimized for mapping.1
- Scalp block with a calculated total dose, because pins and incision hurt most, with large volumes: long-acting local anesthetic to the operative-side nerves and pin sites.1
- Position for access; rescue kit ready. Padded, semi-lateral, face in view, drape off her mouth; LMA, video laryngoscope and induction drugs, ice-cold irrigation for seizures.1
Breaking down the answer
- Selection predicts success — patient refusal and inability to cooperate or lie still rule it out; sleep apnea, persistent cough and profound dysphasia weigh against it.2 Cognitive decline, dysphasia and poor performance status predict emotional intolerance.1
- Monitored sedation or asleep-awake-asleep — the difference is whether an airway device is placed; both give similar patient experience, and sedation alone gives shorter operative times.1 Changes if: a difficult airway or obesity moves me toward a planned airway during opening.
- The block is the anesthetic — pain comes mainly from pinning, drilling and positioning, so a complete scalp block plus surgeon infiltration does most of the work;1 the dose total is calculated first to avoid systemic toxicity.
- Airway risk comes from oversedation — obstruction and hypoventilation happen mainly under sedation, and rescue is harder once the head is pinned.1 Capnography by nasal cannula and a pre-agreed rescue plan show foresight.
- Seizures are expected — cortical stimulation provokes them; prophylaxis, cold irrigation and small sedative doses are prepared before mapping starts.1
- Conversion is rare but rehearsed — conversion to general anesthesia is about 2–3%.1
Follow-up question
During stimulation of the frontal operculum she stops speaking, her right face starts twitching, and within 30 seconds the right arm is jerking and she is becoming unresponsive. What do you do?
Follow-up answer
HeadlineA spreading stimulation-induced focal seizure; I tell the surgeon to stop stimulating and irrigate the cortex with ice-cold saline.
Cold irrigation is the standard first abortive measure.1 At the same time: jaw thrust, 100% oxygen, and her head and lines protected from movement in the pins. If it continues, a small propofol bolus.1 If it generalizes and lasts five minutes, it is status epilepticus: a full benzodiazepine dose, then a second-line drug.3 If she cannot protect her airway or stays obtunded, an LMA or intubation, and we continue asleep. I reassess her neurologic state before mapping resumes and tell the surgeon whether testing is still reliable.
Pitfalls that cost points
- Deep sedation during mapping, which ruins testing and endangers the airway.
- Giving a large anticonvulsant or sedative dose for a brief seizure that cold irrigation would have stopped.
Rapid-fire
Q: Which nerves does a scalp block cover? A: Supraorbital, supratrochlear, auriculotemporal, zygomaticotemporal, and greater and lesser occipital nerves.1
Q: Which sedatives suit monitored sedation? A: Dexmedetomidine or carefully titrated propofol, often with low-dose remifentanil.1
Q: What is the most painful part of the procedure? A: Pinning, drilling and positioning.1
Q: What are the indications? A: Lesions near language, motor or sensory cortex, and epilepsy surgery needing mapping or electrocorticography.1
Q: When does a seizure become status epilepticus by the AES timeline? A: Initial therapy starts at 5 minutes of seizure activity.3
Numbers to know
| Item | Value |
|---|---|
| Conversion to general anesthesia | About 2–3%1 |
| Scalp block nerves | Six per side1 |
| Benzodiazepine start for status | 5 min of seizure activity3 |
| Second-line drug for status | From 20 min3 |
Links
- Seizure disorders, Dexmedetomidine and ketamine, Local anesthetic systemic toxicity, Raised intracranial pressure: evaluation and reduction, Anticipated difficult airway and the ASA algorithm
- AES Guideline on Treatment of Convulsive Status Epilepticus (2016)
Sources
- 1.Anesthesia for Awake Craniotomy · OpenAnesthesia, 2026 · openanesthesia.org
- 2.Anaesthesia for Awake Craniotomy (Anes-PP-023) · Aga Khan University Hospital, Department of Anaesthesiology, 2023 · aku.eduInstitutional guideline; cited only for the contraindication list.
- 3.Evidence-Based Guideline: Treatment of Convulsive Status Epilepticus in Children and Adults · American Epilepsy Society, 2016 · journals.sagepub.com
Facts on this page were checked against these sources on Oct 16, 2026. Guidelines change; confirm doses against current institutional protocols.