Awake Craniotomy
- Access
- PIV x2, pre-induction arterial line (before nasal trumpets, before foley, before scalp block)
- Airway
- See below. Can consider nasal cannula with ETCO2 if BMI is not too high
- Induction
- See below
- Maintenance
- TIVA (propofol/dexmedetomidine/remifentanil/phenylephrine)
- Emergence
- Awake
- Antibiotics
- Cefazolin
- Position
- 90 Left
Start dexmedetomidine as soon as patient is in room and hooked up, 0.3-0.5 mcg/kg/hr. Remifentanil runs at 0.02-0.04 mcg/kg/min. Propofol will be 40-100 mcg/kg/min PRN depending on patient, stability, and effectiveness of scalp block.
Notes
The beats: dexmedetomidine once in room (consider 0.5 or 0.8 mcg/kg bolus over 8 min). Arterial line. Increase sedation (start remifentanil 0.02 mcg/kg/min). Then afrin, lidocaine, nasal trumpets. Connect circuit, deepen sedation with propofol. Then foley and scalp block. Deeper but spontaneously breathing for pinning and bone removal. Try to get BIS on after they pin and map.
Then awake (and remove trumpets) for mapping and neuro monitoring. Can utilize remifentanil in increasing increments of 0.01 mcg/kg/min to help patient tolerate positioning/back pain. Once ready to start closing up, can deepen sedation. May or may not need to replace airway management (trumpets, LMA).
Airway: Afrin for bilateral nares. Then 2% lidocaine with atomizer (long metal stick) down bilateral nares. 5% lidocaine ointment/jelly to apply to nasal trumpets, insert both. Then hook up to double lumen ETT connector, which goes to gooseneck connector and then circuit for spontaneous breathing.
To rescue: 1) use tegaderm to cover mouth. 2) LMA insertion, but must be deep.
Tidal volumes 150-200 mL but more is superb.
Foley: With urethral lidocaine, inserted after airway secured.
Scalp block: Must have sufficient coverage. Supraorbital, supratrochlear, auriculotemporal, greater and lesser occipital nerves. Schlichter uses 0.25% bupivacaine.
Positioning: Ensure TIVA pole is next to patient trunk/arm. Large mayo stand is between the pole and patient head, which is where a drape will go. Must have enough space to maneuver under and chat and rescue airway. But enough space so neurosurgery can place their mapping probe.
Dura: Start backing down on sedation.
Time to wake up? Downtitrate propofol, dexmedetomidine. Remifentanil is last. Eventually, everything off.
When awake: Check motors on side opposite of lesion. Have propofol in line to rescue from seizing (surgeon will utilize ice saline). Have fluorescein ready if surgeon requests.
Dry mouth: Have ice water cup with swabs.
Notes
Meds: levetiracetam (1-2 g), fluorescein, mannitol (0.25 g/kg) sometimes. Have propofol ready in case of seizure.
PONV: Order aprepitant 80 mg prior, ondansetron 4 mg on induction.
Eyes: Could consider lubrication. But Schlichter argues against it, saying patients will want to rub their eyes and move arms.