Craniotomy for intracranial aneurysm

Craniotomy for intracranial aneurysm

Anesthesia type	General
Airway	ETT
Lines and access	PIV x2 Arterial line ± Central line
Monitors	Standard ASA 5-lead EKG Core temp UOP ABG ±CVP Neuromonitoring
Primary anesthetic considerations
Preoperative	Characterize neurologic deficits Controlled hypotension
Intraoperative	Smooth induction Controlled hypotension Have adenosine available Decrease CRMO2 Manage ICP
Postoperative	PONV
Article quality
Editor rating	Comprehensive
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A craniotomy for an intracranial aneurysm is a neurosurgical procedure performed to surgically treat intracranial aneurysms to prevent or manage rupture, which can be life-threatening.

Overview

Background

• Intracranial aneurysms are defects of arterial walls which can occur at any of the major bifurcations of the Circle of Willis.
• Most are treated endovascularly
• The Hess and Hunt scale predicts mortality based upon neuro exam findings:

Hunt-Hess Grading System for Aneurysmal Subarachnoid Hemorrhage
Grade	Description	Mortality
I	Asymptomatic, mild headache, slight neck stiffness	2%
II	Moderate-to-severe headache, neck stiffness, no neurologic deficit (other than cranial nerve palsy)	5%
III	Drowsiness, confusion, mild focal neurologic deficit	15-20%
IV	Stupor, moderate-to-severe hemiparesis	30-40%
V	Coma, decerebrate posturing	50-80%

Indications

• Complex aneurysms which cannot be definitively treated endovascularly

Surgical procedure

• The procedure is performed through a craniotomy
• For cerebral aneurysms, approach is typically through the sylvian fissure to expose the circle of Willis
• Aneurysms are treated using microsurgical clip ligation, which attempts to isolate defective aneurysmal wall and preserve flow through the vessel

Preoperative management

Patient evaluation

System	Considerations
Airway	If acute, consider RSI
Neurologic	Distinguish whether aneurysm has ruptured or not Identify any neurologic deficits
Cardiovascular	Evaluate baseline blood pressure If ruptured: May be treated with vasodilator to maintain controlled hypotension May present with ST and T-wave changes, wall motion abnormalities, and elevated troponin Neurogenic stunned myocardium from catecholamines May be misdiagnosed as ACS