Neuroanesthesia Pt. 3 (Exam I) Flashcards
1
Q
Sharp spiking waves noted on an EEG would make the CRNA consider what phenomenon occuring to the patient?
A
Seizures
1
Q
Delta waves noted on an EEG would make the CRNA consider what phenomenon occurring to the patient?
A
- Deep Sleep (or Anesthesia)
- Tumor
- Stroke
2
Q
What are characteristics of delta waves?
A
- 1-4 hz
- High amplitude
- Low frequency
3
Q
What things can cause interference in an EEG reading?
A
- Hypoglycemia
- Body/Eye movement
- Lights (bright & flashing)
- Sedatives
- Caffeine
4
Q
Why is burst suppression done during aneurysm clip placement?
A
- Increases exposure
- Decreases pressure around aneurysm
- ↓ CMRO₂ = brain protection
5
Q
What is an analyzed EEG signal over 5-10 seconds called?
A
an epoch
6
Q
BIS Values:
85 - 100 = ?
40 - 60 = ?
A
85 - 100 = Normal awake cortical activity
40 - 60 = Consistent w/ GETA
7
Q
Single seizures (meaning one-off episodes of seizures) may result from transient abnormalities such as….
A
- Hypoglycemia
- ↓Na⁺
- ↑Temp
- Brain injury
- Drug toxicity
8
Q
What seizure class can be mistaken for mental illness due to feeling/seeing/hearing things that aren’t there?
A
Focal Seizures
9
Q
What’s another name for focal seizures?
A
Partial Seizures
10
Q
What seizures are characterized by affecting both sides of the brain and muscle spasms?
A
Generalized Seizures
11
Q
What are the subcategories of generalized seizures?
A
- Tonic-Clonic (Grand Mal)
- Clonic
- Tonic
- Atonic
- Myoclonic
- Absence (Petite Mal)
12
Q
What age group is at higher risk for petit mal seizures?
A
Children
13
Q
Clonic seizures are defined by…
A
rhythmic jerking
14
Q
What generalized seizure disorder subtype has the highest risk of falling?
A
Atonic
15
Q
Which anti-seizure drugs reduce influx of Na⁺ & Ca⁺⁺ ?
A
- Lamotrigine (Lamictal)
- Carbamazine (Tegretol)
16
Q
Which anti-seizure drugs increase GABA?
A
Valproate
17
Q
Which anti-seizure drugs decrease excitatory neurotransmitter activity?
A
Levetiracetam (Keppra)
18
Q
How does Keppra work?
A
Decreased glutamate & aspartate activity by binding to SV2A (synaptic vesicle 2A)
19
Q
What two drugs should be avoided in order to prevent seizure occurrence in neuro patients?
A
- Etomidate (possibly lowers seizure threshold)
- Meperidine
20
Q
What anesthetic drugs are best for seizures?
A
- Propofol
- Barbiturates
- Benzodiazepines
- Mg⁺⁺
21
Q
What metabolite of meperidine can build up and cause seizures?
A
Normeperidine
22
Q
What is status epilepticus?
A
- Two or more seizures without a return to consciousness
- Continuous seizure activity
Life-Threatening Emergency
23
Q
What is the treatment for status epilepticus?
A
- Airway & Ventilation
- Treat hypoglycemia
- Anti-epileptic anesthetics (prop, barbs, bnzos)
- Muscle relaxants
24
Which common autoimmune disease affects the CNS via demyelination?
Multiple Sclerosis
25
What gene is MS inherited from?
Trick question. Not directly inherited
26
What disease is characterized by the following:
- Inflammation
- Demyelination
- Axonal damage in the CNS specifically
Multiple Sclerosis (MS)
27
MS is typically a ___ progession, with onset most common after the age of ______.
slow progression : age of 35
28
What demyelinating disease is characterized by symptom development over a few days then stabilization and then temporary improvement?
MS
29
What is a common 1st sign of multiple sclerosis? Why?
Visual disturbances from optic nerve demyelination
30
How efficacious are drugs for MS?
Decrease duration of MS relapse but don't really alter disease progression
31
What drugs are commonly used for MS?
- Corticosteroids
- Interferon
- Azathioprine
- Methotrexate
32
How do corticosteroids treat MS?
- Anti-inflammation
- Restoration (to a degree) of the BBB
33
What patients are candidates for interferon for treatment of MS? Why?
- Rapidly progessing disease
- Cardiac toxicity
*
34
What type of drug is azathioprine?
Purine analogue immunosuppressant
35
How does methotrexate treat MS?
Slows progression through immunosuppression/anti-inflammatory effects.
36
Should MS medications be continued on the day of surgery?
yes; typically
37
What is the anesthetic relevance of baclofen pumps for MS patients?
Baclofen will increase sensitivity to non-depolarizing paralytics.
38
What paralytic should be avoided in MS patients? Why?
**Succinylcholine**
Due to upregulation of extrajunctional ACh receptors
39
What are risk factors for MS relapse? (that anesthesia can help regulate)
- Fever / Hyperthermia
- Infection
- Emotional stress (consider versed pre-op)
40
What is another name for Acute Inflammatory Demyelinating Polyradiculoneuropathy?
Guillain Barre Syndrome (GBS)
41
Guillan Barre Syndrome (GBS) is oft preceded by an _______.
infection
42
What is often the 1st sign of GBS?
"Pins & needles" and numbness
43
In GBS, weakness begins in the _____, and then spreads to the ______.
begins in the legs and then spreads to the upper body
44
What are the most serious signs associated with GBS?
- Difficulty swallowing
- Impaired ventilation
45
What drug should absolutely be avoided in GBS? Why?
Succinylcholine due to upregulation of ACh receptors
46
Autonomic dysfunction is possible in GBS but not MS. T/F?
False. Autonomic dysfunction can occur in both
47
When is hypertension seen with a GBS patient during an anesthetic case?
Laryngoscopy
48
What aspect of anesthesia tends to cause hypotension seen with a GBS patient during an anesthetic case?
Positive airway pressure
49
What kind of anesthetic technique is likely inappropriate for GBS patients? Why?
MAC
- Likely to have airway reflex dysfunction & respiratory compromise
50
What paralytic should be avoided with GBS?
Succinylcholine
51
What are the three components of Parkinson's Disease process?
- Loss of dopaminergic fibers of the basal ganglia
- ↓ NE production
- Lewy Body development
52
What causes the movement disorder aspect of Parkinson's?
Loss of dopaminergic neurons of the basal ganglia
53
What is the name for the α-synuclein clumps of proteins developed in Parkinson's disease?
Lewy Bodies
54
What is the most important risk factor for development of Parkinson's Disease?
Age
55
What acronym showcases the sign/symptoms associated with Parkinson's?
TRAP
**T**remors
**R**igidity
**A**kinesia
**P**osture
56
Where, regionally, does muscle rigidity in Parkinson's patients first appear?
Proximal muscles of the neck resulting in "loose arm swinging".
57
How are the tremors of Parkinson's disease usually characterized?
- Pill-Rolling = Rhythmic w/ alternating flexion/extension of digits.
- Shaking that usually starts on one side
58
Tremors in Parkinson's disease are usually more prominent when moving. T/F?
False. Tremors more prominent at **rest**.
59
Is there an autonomic dysfunction component to Parkinson's? What is the result?
Yes; results in the following being more common:
- Respiratory obstruction
- Aspiration pneumonia
60
What are the two treatment goals with Parkinsons?
- Increase Dopamine in basal ganglia
- Decrease effects of excess ACh
61
How do Levodopa/Carbidopa work?
- Levodopa - crosses BBB and forms into dopamine
- Carbidopa (decarboxylase inhibitor) prevents levodopa breakdown prior to crossing of BBB.
62
What are the side effects of Levodopa/Carbidopa?
- Dyskinesias
- Altered heart contractility
- Orthostatic Hypotension
- N/V
63
What is the success rate for surgical treatment (DBS) of Parkinson's disease?
What patients are candidates for surgical treatment?
- 70%
- Reserved for patients w/ disabling & medically refractory symptoms
64
What type of anesthesia should be considered with patients w/ dementia?
TIVA
65
Huntington's Disease is a _______ disorder that is characterized by enlargement of the ____________.
Movement disorder (genetic)
Enlargement of lateral ventricles
66
ALS is a disorder characterized by what?
Amyotrophic lateral sclerosis
Disorder characterized by progressive degeneration of motor neurons.
67
What is the pathophysiology of myasthenia gravis?
Destruction of nACh receptors at the NMJ
68
What are common triggers for development of myasthenia gravis?
- Stress
- Surgery
- Infection
- Pregnancy
69
What are the hallmark symptoms of MG?
- Weakness (centrally first then peripherally)
- Rapid exhaustion of skeletal muscles followed by partial recovery with rest.
70
How is MG diagnosed?
- Blood Test
- Edrophonium (Tensilon) test
- EMG nerve stimulation
71
What autoimmune disorder may result from a tumor forming on the thymus gland?
Myasthenia Gravis (MG)
72
What type of drug is edrophonium?
Rapid-acting anticholinesterase medication
*Have atropine available*.
73
What occurs with a tensilon test?
Edrophonium is given to a patient with presumed MG, if symptoms improve then MG is diagnosed.
74
What other disorder may be diagnosed with a Tensilon test (other than MG) ?
Lambert Eaton Myasthenic Syndrome
75
How is myasthenia gravis treated?
Anticholinesterases
- Pyridostigmine
- Neostigmine
*Make more ACh available at NMJ*.
76
What is the pathophysiology of cholinergic crisis?
Excess ACh from:
- Too much AChesterase inhibitors
- Pesticides
- Nerve gas (Sarin)
77
What is the deadliest symptom associated with severe cholinergic crisis?
Profound muscle weakness/ flaccid paralysis
*Due to continuous depolarization of postsynaptic membrane*.
78
What acronym describes cholinergic toxicity?
**S**alivation
**L**acrimation
**U**rination
**D**efecation
**G**I Upset
**E**mesis
79
Myasthenic Crisis vs Cholinergic Crisis Chart
80
What drug can be used to differentiate Myasthenic vs Cholinergic Crisis?
Edrophonium
- Edrophonium improves Myasthenic crisis
- Edrophonium worsens Cholinergic crisis
81
What drugs should be avoided (besides succinylcholine) in MG patients?
- CCBs
- Mg⁺⁺
82
When are immunosuppressants indicated for MG treatment?
When skeletal muscle weakness is not adequately treated with AChe inhibitors.
83
How does plasmapheresis treat MG? Is this permanent?
Plasmapheresis removes antibodies attacking the NMJ from the blood.
*Purely a temporary measure*.
84
What surgery is used to treat MG?
Thymectomy
*Treatment of choice for majority of MG patients, 75% show improvement or remission*.
85
What type of extubation is required for MG patients? Why?
Awake extubation due to ↑ risk of aspiration
86
MG patients are resistant to _______ paralytics but sensitive to _______ paralytics.
Resistant to succinylcholine
Sensitive to Non-depolarizing paralytics
**Consider using VAA for muscle relaxation**.
87
Where do antibodies attack in ELMS (Eaton-Lambert Myasthenic Syndrome) ?
Presynaptic Ca⁺⁺ channels at the NMJ
88
With ELMS, muscle strength improvement occurs with....
repeated use
89
ELMS is associated with what type of lung cancer?
Small-cell lung cancer
90
ELMS patients are sensitive to _______ paralytics.
Non-depolarizing
91
Proximal muscles are more effected in ________ than in MG.
ELMS
92
Are reflexes increased or decreased in ELMS?
Decreased
93
Is autonomic dysfunction a component of ELMS?
yes
94
MG vs ELMS Chart
95
Is autonomic dysfunction a component of MG?
**No**
