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The Awake Craniotomy. April 2013 Mark Angle, M.D. Kuwait City. It’s how we started :. The Awake Craniotomy. Classical Indications Brain - mapping Cortical Stimulation Cortical Recording Patient- directed tumour resection in eloquent regions Positive Mapping – 5% deficits
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The AwakeCraniotomy April 2013 Mark Angle, M.D. Kuwait City
It’s how westarted : The AwakeCraniotomy
Classical Indications • Brain-mapping • Cortical Stimulation • Cortical Recording • Patient-directedtumourresection in eloquentregions • Positive Mapping – 5% deficits • NegativeMapping – 2% deficits AwakeCraniotomy
Whybother ? • Neuroimaging (FMRI, Activation PET, ESAM) renders 60-70% accuracy • Neuroplasticity and transferrence alter classicalfunctionalanatomy • Neuronavigationlosesaccuracy post durotomy and duringresection AwakeCraniotomy
Whybother ? • Generally good physiological control (BP, pCO2, SaO2) • Acceptable failure rates 5-8 % • Acceptable deficit rates @ 15 % AwakeCraniotomy
Whybother? • Function-limitedtumourresection • Higher rate of total resection • Maximum cytoreduction • 20-30% deficitsacutelydiminishing to 5-8% at 3 months AwakeCraniotomy
Whyanaesthetistshatethem : • Failures : • Loss of communication 5% • Seizures 2% • Loss of airway 2% • Loss of compliance 2% • Long periods of jeopardy • Unsecuredairway • Risk of : • Vomiting • Obstruction • Hemorrhage • Hyperventilation • Deficits • “A different type of practice” AwakeCraniotomy
Goals • Conditions for surgical success • Patient compliance • Patient safety • Patient comfort (forgiveness) Awake Craniotomy
Understanding the goals • Surface mapping for corticectomy • Limited wakefulness • Brain mapping for tumours in eloquent regions • Moderate wakefulness • Function-limited tumour resection • Prolonged wakefulness Awake Craniotomy
Understanding the goals • Functions to be tested determine permissible degrees of sedation • SSEP • Motor • Speech • Cognition Awake Craniotomy
Patient selection • Exclude uncooperative patients • Exclude significant deficits : motor, cognitive and memory • Exclude panic and claustrophobia • Exclude children ≤ 8 years Awake Craniotomy
Patient assessment • Comprehension / Cooperation • Airway • Mobility / Positioning • Pain tolerance • Surgicalrisks : • Hemorrhage • Seizures • Co-morbidities Awake Craniotomy
Pre-surgical • Explanation / Complicity /Consent • Clonidine 0.1 – 0.3 mg P.O. • Nabilone 0.5 – 1.0 mg P.O Awake Craniotomy
Induction • Zofran 8 mg • Propofol / Remifentanyl“cocktail” • Provocation / Sensitivity testing • Obstruction • Apnea Awake Craniotomy
Monitoring • Arterial line contralateral • Foley catheter • Nasal Et CO2 • SaO2 • 2 IV peripheral : bilateral Awake Craniotomy
Local Anaesthesia • Mayfield pin sites • Scalp block : • Auriculo-temporal • Zygmatico-temporal • Supra-Orbital • Greater-Occipital • Lesser-Occipital • Incisional block Awake Craniotomy
Positioning : (Post-Mayfield) • Awake if possible • No weight-bearing by Mayfield • Hands lightlyrestrained • Free movement of legs • Sight-linesclear • Airway accessible • Fresh-air blower Awake Craniotomy
Maintenance : TIVA • Droperidol / Fentanyl • Propofol/ Remifentanyl • Dexmedetomidine Awake Craniotomy
Maintenance : • Remifentanyl/Propofol infusion, titrated to stimulation • RepeatClonidine / Nabiloneathour 6 • Sips of H2O as requested • Distraction/Communication Awake Craniotomy
Events • Obstruction • Hyperventilation / Apnea • Vomiting • Seizures • Loss of compliance : pain, panic • Deficits • Emergence • Closureunderdeepsedation • Infusion (atlower dose) continuedintoPACU Awake Craniotomy
Conclusions: • High success and satisfaction rates • Clear facilitation of aggressivetumourresectionparadigm • Demanding on both patient and anaesthetist Awake Craniotomy