Exam II: Neurosurgical Anesthesia Flashcards
Space-occupying ____ and ↑’d ____ volume
[Challenges of a Craniotomy]
lesions, intracranial
Closed non-expandable___ ___“closed box”
-Brain tissue (___), blood (___) and CSF (___)
[Challenges of a Craniotomy]
cranial vault
80%, 12%, 8%
Altered vasoreactivity and ____
[Challenges of a Craniotomy]
autoregulation
Control of___, ___, CPP, ICP and brain swelling
[Challenges of a Craniotomy]
CBF, CBV
Varying levels of ___stimulation occur
-Scalp, skull, dura elicit ___ noxious stimuli
-___tissue almost free from nocioceptive nerve tissue.
[Challenges of a Craniotomy]
noxious
increased
Brain
Unfamiliar monitoring , HOB away from ___
[Challenges of a Craniotomy]
anesthetist
Access to ___is not readily available
[Challenges of a Craniotomy]
airway
Cushing’s reflex: ___=___=___
*Respect ↑’d ICP ability to damage___
[Challenges of a Craniotomy]
↑ICP =↑ HTN = ↓ HR
brain
Flow & ___ are coupled:
___ also ___ & ___
___can alter this coupling
[Challenges of a Craniotomy]
metabolism
↓CMRO2 also ↓CBF & ICP
Drugs
Blood loss & ___can change rapidly
[Challenges of a Craniotomy]
hemodynamics
___ and vasodilators are usually inline and ready for immediate titration.
[Challenges of a Craniotomy]
Vasoconstrictors
Goal is “___” brain not a “___” brain
[Challenges of a Craniotomy]
relaxed, tight
___soaked gauze utilized
[Challenges of a Craniotomy]
Epinephrine
___ surgery
[Challenges of a Craniotomy]
Tedious
Intense noxious stimulation at___ and ___ with little in the ___
[Challenges of a Craniotomy]
beginning, end, middle
Head ROM is fixed due to ___ ___.
[Challenges of a Craniotomy]
cranial pinning
Glucose is the ___ substrate of metabolism
[Metabolism of the Brain]
primary
____worsens hypoxic injury
[Metabolism of the Brain]
Hypoglycemia
The metabolic rate of the brain is measured in ___ ___
[Metabolism of the Brain]
oxygen consumption
Cerebral metabolic rate of oxygen consumption-___
[Metabolism of the Brain]
CMRO2
Adult human brain = ___-___ gms
[Cerebral Blood Flow]
1300-1400
___-___ ml of blood per minute (___/___)
Around ___of total cardiac output
[Cerebral Blood Flow]
650-700, 700/5000
14%
CNS has a ___-___coupling ensuring a supply and demand match:
Increased brain metabolic activity increases ___&___
[Cerebral Blood Flow]
flow-metabolism
CBF & ICP
The brain can increase flow as much as ___-___% of cardiac output
[Cerebral Blood Flow]
15-20
CBF averages ___mL/___ gm/min but can vary regionally from ___-___ mL/___ gm/min
[Neuro Electrical Activity and CBF]
50 , 100, 30-300, 100
CBF < ___ mL/100 gm/min = slowing of EEG
[Neuro Electrical Activity and CBF]
25
CBF ≈ ___-___ mL/100 gm/min = isoelectric EEG
[Neuro Electrical Activity and CBF]
15-20
CBF___ mL/100 gm/min = irreversible injury
[Neuro Electrical Activity and CBF]
< 10
___ & ___more sensitive to hypoxic brain injury than other parts of the brain
[Neuro Electrical Activity and CBF]
Hippocampus & cerebellum
CPP = ___-___ or ___ which ever is higher
[Cerebral Perfusion Pressure (CPP)]
MAP – ICP or CVP
Since ___/___ is small CPP is essentially = to ___
[Cerebral Perfusion Pressure (CPP)]
ICP/CVP, MAP
CPP ___ torr = EEG changes
[Cerebral Perfusion Pressure (CPP)]
< 50
CPP ___ torr = irreversible damage
[Cerebral Perfusion Pressure (CPP)]
< 25
Autoregulation is diminished below ___torr
[Cerebral Perfusion Pressure (CPP)]
50
CBF is autoregulated at MAP between ___-___ torr
[Cerebral Blood Flow (CBF)]
50-150
___, ___ & CMRO2 are closely linked
[Cerebral Blood Flow (CBF)]
CBF, ICP
___/___metabolism coupling occurs
[Cerebral Blood Flow (CBF)]
Flow/cerebral
When CMRO2 decreases then ___ & ___ decreases
[Cerebral Blood Flow (CBF)]
CBF & ICP
Luxury perfusion: ___ > ___
Do not want ___ brain surgery
[Cerebral Blood Flow (CBF)]
CBF, CMRO2
during
CBF is ____ to PaCO2
[Cerebral Blood Flow (CBF)]
proportional
When Vm doubles CBF ___by half.
[Cerebral Blood Flow (CBF)]
deceases
CBF increases ___-___% for every ___ C° temperature
[Cerebral Blood Flow (CBF)]
5-7, 1
Volatile anesthetic drugs (above ___MAC) cause a CNS flow/metabolism uncoupling:
They ___CRMO2 but unfortunately also cause cerebral ____ so CBF and ICP ___
[Anesthesia Drugs & CMRO2, CBF, ICP Coupling]
1.5
reduce, vasodilation, increase
IV Anesthetic drugs preserve CNS ___/___ coupling:
[Anesthesia Drugs & CMRO2, CBF, ICP Coupling]
flow/metabolism
IV anesthetic drugs ___CMRO2 but do not cerebrally ___
[Anesthesia Drugs & CMRO2, CBF, ICP Coupling]
reduce , vasodilate
___CRMO2, CBF and ICP ___ remains intact
[Anesthesia Drugs & CMRO2, CBF, ICP Coupling]
Decrease, coupling
Different agents & doses have ___ effects
[Volatile Inhalational Agents, CBF & ICP]
different
All volatiles ___ cerebral vascular resistance
Dose dependent impairment of ___
Greater than __-___MAC ___ autoregulation resulting in cerebral vasodilation & ___/___ decoupling
[Volatile Inhalational Agents, CBF & ICP]
↓
autoregulation
1-1.5 , impairs
flow/cerebral metabolism
Increases ___, ___ and ICP
[Volatile Inhalational Agents, CBF & ICP]
CBV, CBF
___CMRO2 and even ___cortical activity
Can be ___ at high doses
[Volatile Inhalational Agents, CBF & ICP]
Decrease, abolish
neuroprotective
___attenuates the increases in ICP
[Volatile Inhalational Agents, CBF & ICP]
Hyperventilation
N2O still used, considered ___ by some
-Expands___gas spaces
-Increases ___, ___ and can actually increase ___
[Nitrous Oxide and Craniotomy]
neurotoxic
closed
CBF, ICP, CMRO2
Avoid N2O when:
Presence of ___ air such as during a recent craniotomy, repeat craniotomy or cranial ___.
[Nitrous Oxide and Craniotomy]
intracranial, trauma
Avoid N2O when:
___potential signal is inadequate
Evidence of___ ICP
___ brain
[Nitrous Oxide and Craniotomy]
Evoked
increased
Tight
Barbiturates: decrease ___, ___, and __, inhibit excitatory neurotransmitter receptors, and causes a ___ of EEG
[IV Agents and CBF & ICP]
CBF, ICP and CMRO2, slowing
Propofol:____ ___ ___CBF, CMRO2 isoelectric EEG at ___ mcg/kg/min
Very good at maintaining ___/___ metabolism coupling
[IV Agents and CBF & ICP]
dose dependent decrease, 500
flow/cerebral
Etomidate: ___CBF, ICP and CMRO2 but can cause seizures in patients with ___ history
[IV Agents and CBF & ICP]
decreases, seizure
Opioids: ___ ____ ___ in CBF, CMRO2, ____metabolite can cause seizures
[IV Agents and CBF & ICP]
dose dependent decreases, Demerol
___: anticonvulsant, decreases CBF, CMRO2, respiratory depression limits their use. Contraindicated in patients with ___ ICP
[IV Agents and CBF & ICP]
Benzodiazepines
↑’d
Ketamine: ___ effects, ↑ ICP (___%), CBF
[IV Agents and CBF & ICP]
dissociative, >80%
Muscle Relaxants:
Depolarizers: ___ ICP, CBF, CMRO2, contraindicated in ___ muscle, CVA, motor neuron lesions.
[IV Agents and CBF & ICP]
Increase, denervated
Nondepolarizers: effects are ___ anticonvulsants such as dilantin cause ___ dosage requirements.
[IV Agents and CBF & ICP]
small, increased
Fluid Management
-Avoid ____containing solutions
[Fluid Management for Craniotomy]
dextrose
-Limit volume of___ and use ___and NS for volume resuscitation
[Fluid Management for Craniotomy]
LR, colloid
-Limit ___ to 1 to 1.5L to avoid coagulopathy
[Fluid Management for Craniotomy]
hetastarch
-Maintain Hct at ___ to ___
[Fluid Management for Craniotomy]
30% to 35%
-Mild volume expansion for ___ ___may help reduce vasospasm
[Fluid Management for Craniotomy]
aneurysm clipping
-Kee patients ___, isotonic, and isooncotic
[Fluid Management for Craniotomy]
isovolemic
Monitoring for Craniotomy
-Electrocardiography
-Direct intraarterial blood pressure monitoring
-End-tidal CO2, pulse ox, ABG analysis
-Peripheral nerve stim
-CVP
-Body temp measurement
-UOP
-Electroencephalography or somatosensory evoked potentials
-Cerebral oxygen monitoring
[Monitoring for Craniotomy]
It’s more important to accomplish a ___ ___ than any particular drug combination
[Goals of Induction ]
smooth induction
Avoid ___ ICP or ___ CBF
[Goals of Induction ]
↑, compromising
Avoid hypertension which ___ CBF and ___ ICP
[Goals of Induction ]
↑, ↑
Avoid hypotension which ___
[Goals of Induction ]
↓ CPP
Maximize ___drainage
Avoid excessive ___ ___
HOB ↑ ___
[Goals of Induction ]
venous
neck flexion
> 15°
Hyperventilation during___time or ___period
[Goals of Induction ]
apnea, preoxygenation
Opioids can ___SNS outflow
[Goals of Induction ]
blunt
Adequate muscle relaxant to prevent___/___
[Goals of Induction ]
bucking/cough
___, ___ and controlled is a must!
[Goals of Emergence ]
Slow, smooth
Neurological fxn intact prior to ___
[Goals of Emergence ]
extubation
Prevent ___, ___ or bucking on ETT
[Goals of Emergence ]
straining, coughing
Various opinions regarding ___emergence.
-Re-establishing spontaneous breathing ___ skin closure and pin removal
-Once pins (noxious stimulation) is removed then return of __ ___may be delayed.
[Goals of Emergence ]
optimal
prior to
spontaneous respirations
HOB returned to ___ and ___
[Goals of Emergence ]
machine and CRNA
Rapid awakening promotes ___assessment
[Goals of Emergence ]
neuro
___genital
Neo___
Benign
Mal___
I___ or ____
Cyst
Abscess
Vascular
Hematoma
AVM
[Types of Intracranial Mass Lesions]
Con—
—plastic
—ignant
-nflammatory or Infectious
___: above the tentorium
(4)
[Resection of Mass Lesions]
Supratentorial
Headache
Seizures
hemiplegia
aphasia
___: below the tentorium
___ ___ (ataxia,nystagmus)
Brain stem compression (___ or ___)
[Resection of Mass Lesions]
Infratentorial
Cerebellar dysfunction
altered mental status or altered respirations
Intracranial mass symptoms are present based on
___ rate:
[Resection of Mass Lesions]
Growth
Slow growing are typically ___
[Resection of Mass Lesions]
asymptomatic
___ ___ cause acute neurological deficits
[Resection of Mass Lesions]
Fast growing
Location: deficits___ with location of masses
[Resection of Mass Lesions]
align
ICP: ___ ___ is common
[Resection of Mass Lesions]
Intracranial HTN
Common Neurological symptoms usually present are:
Reduced ___ function
Headache
___neurological deficits
[Resection of Mass Lesions]
cognitive
Focal
Majority of intracranial mass surgeries are ___
[Resection of Mass Lesions]
supratentorial
Mass lesions all have the same___ implications
[Resection of Mass Lesions]
anesthetic
Brain___ & ____ may be evident on CT
[Resection of Mass Lesions]
edema & midline shift
Evaluate & document ___ deficits
[Resection of Mass Lesions]
neurological
Many times on (3)
Abnormal ___ and glucose
[Resection of Mass Lesions]
anticonvulsants,steroids,diuretics
electrolytes
Patients present with:
Headache
Seizures
Reduction in ___ and ___ functions
___ neurological deficits
[Resection of Mass Lesions]
cognitive and neurological
Focal
Avoid ___, ___ preoperative
[Resection of Mass Lesions]
benzodiazepines, opioids
HOB ↑ ___ to ___° to control ICP
[Resection of Mass Lesions]
15°-30
Signs and symptoms of elevated ICP include: (6)
[Resection of Mass Lesions]
Headache
Nausea
Vomiting
Papilledema
Focal neuro deficits
AMS
“Prevention of ___ ___ by treatment administered___ to the ischemic insult” (Longnecker, Anesthesiology, 2008)
[Anesthetic Neuroprotection]
cell death, prior
Neuroprotection can result from:
Decreasing C___, inhibiting protein ___, decreasing production of ___ ___ acids, scavenging reactive oxygen species, inhibiting ___ function, inhibiting ___neurotransmitter receptors.
[Anesthetic Neuroprotection]
CMRO2, kinase C, free fatty, WBC, excitatory
Anesthetic-induced suppression of electrocortical
activity
-allows the brain to tolerate disruption of ___ ___ ___
[Anesthetic Neuroprotection]
metabolic substrate delivery
[Anesthetic Neuroprotection]
___ ___: EEG slows to random burst of electrical activity.
[Anesthetic Neuroprotection]
Burst suppression
+insert 32 Treating elevated ICP
[Anesthetic Neuroprotection]
Vital brain stem centers are ____
-C___ and ___ centers
-RAS, ANS and some ___
[Posterior Fossa Surgery (Infratentorial)]
in close proximity
Circulatory and respiratory
cranial nerves
Infratentorial masses can obstruct CSF at ___ ventricle and lead to ___hydrocephalus.
[Posterior Fossa Surgery (Infratentorial)]
4th, obstructive
Spontaneous ventilation is a form of monitoring ___ ____ ___.
[Posterior Fossa Surgery (Infratentorial)]
respiratory center damage
___ position is most preferred
[Posterior Fossa Surgery (Infratentorial)]
Sitting
↑ risks when ___ ___ system subatmospheric
[VAE with Posterior Fossa Surgery]
open venous
Can occur in any position where __>___
[VAE with Posterior Fossa Surgery]
wound is > heart
Highest incidence (>20%) during___craniotomy
Dependent on volume and rate of entry
Small air bubbles diffuse into pulmonary system
Large air bubbles can impede pulmonary flow leading to ↑ RV afterload ↓ CO
N2O enhances the air embolus
[VAE with Posterior Fossa Surgery]
sitting
Dependent on volume and___
[VAE with Posterior Fossa Surgery]
rate of entry
Small air bubbles diffuse into ___ system
[VAE with Posterior Fossa Surgery]
pulmonary
___ can impede pulmonary flow leading to ↑ RV afterload –>↓ CO
[VAE with Posterior Fossa Surgery]
Large air bubbles
___enhances the air embolus
[VAE with Posterior Fossa Surgery]
N2O
___ETCO2
[Detection of VAE]
Decreased
___oxygen saturation
[Detection of VAE]
Decreased
___ hypotension
[Detection of VAE]
Sudden
Circulatory arrest (___ ___ ___)
[Detection of VAE]
obstructing RV outflow
↑ ET nitrogen due to ___ through ___
[Detection of VAE]
absorption through alveoli
Precordial doppler (most sensitive non-invasive monitor) ___-___ roaring sound heard.
[Detection of VAE]
mill-wheel
___ ___ (most sensitive invasive monitor) 0.25ml air detected.
[Detection of VAE]
Transesophageal echocardiography
Esophageal stethoscope (very faint mill-wheel) ___sensitivity
[Detection of VAE]
very low
Add slide 41
[Treatment of VAE]
Air enters the ___ circulation
[Paradoxical Air Embolism]
systemic
[Paradoxical Air Embolism]
PFO exist in ___-___% of population
[Paradoxical Air Embolism]
30-35%
Further evaluation should be initiated for those who are suspected of having ___ defects (heart murmur)
[Paradoxical Air Embolism]
intracardiac
Surgical ___ may need to be altered to lessen the risks of air entrainment.
[Paradoxical Air Embolism]
positioning
___ intracranial arteries, many types exist
[Cerebral Aneurysm]
Dilated
Complications of aneurysms include: ___, ___ & ___
[Cerebral Aneurysm]
SAH,re-bleeding & vasospasm
___ aneurysm rupture is the leading cause of subarachnoid non-traumatic hemorrhage
[Cerebral Aneurysm]
Sacular
Peak rupture age ___-___ years. gender:
[Cerebral Aneurysm]
55-60, female > male
Majority are ___ & anterior cerebral artery
[Cerebral Aneurysm]
internal carotid bifurcation
Subarachnoid bleed presents usually as an intense headache (___%), ____LOC (45%) with N/V
[Cerebral Aneurysm]
85, transient
HTN develops which can worsen ___bleed
[Cerebral Aneurysm]
SA
___ is impaired so ↓ing BP not a good option
[Cerebral Aneurysm]
Autoregulation
EKG = ___ & ___, non-ischemic in origin with no adverse outcome
[Cerebral Aneurysm]
T & ST ∆s
___ of previously ruptured aneurysm re-bleed with___% mortality
[Cerebral Aneurysm]
50%, 80
Cerebral vasospasm (___%) 4 days ___ ___ is the major cause of mortality and mobidity. Many proposed reasons to occur.
[Cerebral Aneurysm]
30, post rupture
Surgical intervention usually if ___mm clipping
[Cerebral Aneurysm]
> 7
___ procedures have been successful
[Cerebral Aneurysm]
Coiling
Level of external auditory meatus and tragus = ___ ___estimates CPP
[Cerebral Perfusion Pressure]
Circle of Willis
[Cerebral Perfusion Pressure]
Formula: 1 mmHg for each___ cm
[Cerebral Perfusion Pressure]
1.25
Add 48 treatment of vasospasm
Blood collects b/t ___ and __ layers of brain
[Subdural Hematoma (SDH)]
dura and arachnoid
Usually associated with trauma, ___ bleeding not ___
Normocapnia is desired not hypocapnia [Subdural Hematoma (SDH)]
venous, arterial
Greater risks if taking ___, ___ drugs
drugs
[Subdural Hematoma (SDH)]
anticoagulation, anti-platelet
Headache –> drowsiness —> ___ ___ —> ___
[Subdural Hematoma (SDH)]
cognitive decline, obtunded
The sooner the ___ is evacuated the better the outcome
[Subdural Hematoma (SDH)]
hematoma
Surgical options include ___ or ___
[Subdural Hematoma (SDH)]
craniotomy or burr holes
[Treatment of Vasospasm]
___blood pressure and cardiac output
[Treatment of Vasospasm]
Augment
Administer ___agents
[Treatment of Vasospasm]
inotropic
Administer Ca+ channel blockers ___ and ___
[Treatment of Vasospasm]
nimodipine and nicardipine
___ volume expansion
[Treatment of Vasospasm]
Intravascular
Hemodilution (hct ___%)
[Treatment of Vasospasm]
< 32
Correct___natremia
[Treatment of Vasospasm]
hypo
Transluminal ____
[Treatment of Vasospasm]
angioplasty
“Triple H” :
[Treatment of Vaspressin]
hemodilution, hypervolemia and HTN
___progressively grow with time
[AV Malformation]
AVMs
Intracerebral hemorrhage not ___
[AV Malformation]
subarachnoid
Present at an earlier age (___) with bleeding
[AV Malformation]
10-30
Headache and ___present often
[AV Malformation]
seizures
If neuroradiology Rx fails then ___ ___
[AV Malformation]
surgical resection
Extensive blood loss compared with ____
[AV Malformation]
aneurysms
___ and ___ fascilitates surgical resection of AVM
[AV Malformation]
Hyperventilation and mannitol
Same techniques apply to AVM as for ____
[AV Malformation]
aneurysms
10% of neoplasms are ___ in orgin.
Rarely ____
[Pituitary Surgery]
pituitary
metastatic
___-___% are non-secretory
[Pituitary Surgery]
20-50
Hypersecretory tumors can lead to ___ & ___
[Pituitary Surgery]
acromegaly & hyperglycemia
Difficult intubations can be a factor:
-___ facial features
-Laryngeal ___
-____tongue
[Pituitary Surgery]
Enlarged
hypertrophy
Enlarged
Resection is ___ (majority) or ____ approach
[Pituitary Surgery]
transsphenoidal, intracranial
___ has less blood loss, mortality and morbidity
[Pituitary Surgery]
Transphenoidal
Cushing’s disease may be present; patient can present with HTN, ___, ___, ___ and friability of skin
[Pituitary Surgery]
diabetes, osteoporosis, obesity
___ ___may occur post op
[Pituitary Surgery]
Diabetes Insipidus
Remember the airway is shared with ___
[Pituitary Surgery Plan]
surgeon
Thorough airway _____
[Pituitary Surgery Plan]
assessment.
Be ready for potential ___ airway
[Pituitary Surgery Plan]
difficult
ETT placed to the ___side secured to ___
[Pituitary Surgery Plan]
left, chin
Lubricate eyes to prevent ___from entering
[Pituitary Surgery Plan]
fluids
Avoid ___ if air injected
[Pituitary Surgery Plan]
N2O
Avoid hyperventilation as it causes ___ to retract into the ___ hindering resection
[Pituitary Surgery Plan]
pituitary, sella
Raise the ETCO2 to force the ___into view.
[Pituitary Surgery Plan]
pituitary
Be prepared for blood loss as ___ ___ lie in close proximity
[Pituitary Surgery Plan]
carotid arteries
Usually monitored anesthesia care or ___.
[Stereotactic Procedures]
light sedation
Uncomfortable aspects:
securing the halo with ___
drilling a hole in the___,
both of which are performed following ___.
[Stereotactic Procedures]
pins
skull
local anesthetic infiltration
Halo is in ___ position in pinned headframe
[Stereotactic Procedures]
fixed
Halo prevents ___laryngoscopy
[Stereotactic Procedures]
direct
Can use ___ ___ if needed
[Stereotactic Procedures]
fiberoptic bronchoscopy
Careful not to eliminate ____ with too deep of sedation
[Stereotactic Procedures]
respirations
Do not compromise the patients ability to maintain his ____.
[Stereotactic Procedures]
airway
Make an alternate airway plan for ___ and ____.
[Stereotactic Procedures]
oxygenation and ventilation
Malformation where____ protrudes through foramen magnum
[Arnold-Chiari Malformation]
medulla
Classified as Chiari types___through ___.
[Arnold-Chiari Malformation]
I, IV
CSF outflow obstruction, ____
[Arnold-Chiari Malformation]
hydrocephalus
More common in ____
[Arnold-Chiari Malformation]
females
Rx is ____ pressure ___.
[Arnold-Chiari Malformation]
decompressive, relief
Anesthesia implications same as those for ____ ___surgery
[Arnold-Chiari Malformation]
posterior fossa
Patients may also have other ___ ___ besides the head trauma
[Head Trauma]
traumatic injuries
Hypotension, _____ ____
[Head Trauma]
hemodynamic instability
Pulmonary contusions, _____% have hypoxemia
[Head Trauma]
70
Assumed to have a ___ ___ injury
[Head Trauma]
cervical spine
Varying degrees of consciousness, ____
[Head Trauma]
↑ ICP
Brain contusion, ____ injuries
[Head Trauma]
deceleration
Hemorrhage, hematomas, ____, ____
[Head Trauma]
epidural, subdural
Airway challenges, facial fx, ____ ___
[Head Trauma]
full stomach
Primary ___ insult & ____insult
[Head Trauma]
neuro, secondary
Avoid ____
[Head Trauma]
N2O
Treat HTN with ___agent, hyperventilation
[Head Trauma]
increased
Avoid too much hyperventilation as it ___ ____
[Head Trauma]
↓’s CBF
Treat Hypotension with ___ ____ ___
[Head trauma]
α adrenergic agonist
Maintain CPP at ____ mmHg
[Head trauma]
70-110
Treat enhanced vagal tone with ____
[Head trauma]
atropine
Avoid PEEP until after ___ is opened b/c of ____ ICP
[Head trauma]
dura, ↑’d
May have to leave ____ and ____ until ↑ ICP is resolved.
[Head trauma]
intubated and paralyzed
