Anesthetic approach to high-risk patients and prolonged awake craniotomy using dexmedetomidine and scalp block.
BACKGROUND
Awake craniotomy with intraoperative speech or motor testing is relatively contraindicated in cases requiring prolonged operative times and in patients with severe medical comorbidities including anxiety, anticipated difficult airway, obesity, large tumors, and intracranial hypertension. The anesthetic management of neurosurgical patients who possess these contraindications but would be optimally treated by an awake procedure remains unclear.


METHODS
We describe a new anesthetic approach for awake craniotomy that did not require any airway manipulation, utilizing a bupivacaine-based scalp nerve block, and dexmedetomidine as the primary hypnotic-sedative agent. Using this technique, we provided optimal operative conditions to perform awake craniotomy facilitating safe tumor resection, while utilizing intraoperative electrocorticography for motor and speech mapping in a cohort of 10 patients at a high risk for airway compromise and complications associated with patient comorbidities.


RESULTS
All patients underwent successful awake craniotomy, intraoperative mapping, and tumor resection with adequate sedation for up to 9 hours (median 3.5 h, range 3 to 9 h) without any loss of neurological function, airway competency, or the need to provide any active rescue airway management. We report 4 of these cases that highlight our experience: 1 case required prolonged surgery because of the complexity of tumor resection and 3 patients had important medical comorbidities and/or relative contraindication for an awake procedure.


CONCLUSIONS
Dexmedetomidine, with concurrent scalp block, is an effective and safe anesthetic approach for awake craniotomy. Dexmedetomidine facilitates the extension procedure complexity and duration in patients who might traditionally not be considered to be candidates for this procedure.
*Department of Anesthesia ‡Division of Neurosurgery, St. Michael's Hospital, University of Toronto †Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada.
Marco M
MM
Garavaglia
Sunit
S
Das
Michael D
MD
Cusimano
Charmagne
C
Crescini
C David
CD
Mazer
Gregory M T
GM
Hare
Andrea
A
Rigamonti
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000758:Anesthesia; D001008:Anxiety Disorders / Q000150:complications; D001932:Brain Neoplasms / Q000601:surgery; D003399:Craniotomy / Q000379:methods*; D020927:Dexmedetomidine; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives; D008297:Male; D008875:Middle Aged; D009407:Nerve Block; D011183:Postoperative Complications / Q000453:epidemiology / Q000523:psychology; D011595:Psychomotor Agitation; D012306:Risk; D012535:Scalp; D014851:Wakefulness
D006993:Hypnotics and Sedatives; D020927:Dexmedetomidine