E4 Flashcards
What is MAC?
Minimum alveolar concentration = measure of potency of anesthetics
Equilibrium concentration required to prevent the response to a painful stimulus in 50% of patients
What is MAC similar to?
EC50
What factors decrease MAC/increase potency?
Hypothermia Pregnancy Shock Increasing age Acute alcohol ingestion CNS-depressant drugs Decreased CNS NT release
How do opiates inhibit neurotransmission post-synaptically?
Signal via G-proteins –> K+ efflux or Cl- influx –> HYPERpolarizing
What is endogenous analgesia?
Endorphins release to cause absence of pain sensation. Stimulation of A-delta and C fibers stimulates release of endogenous opioids B-endorphin and dynorphin
Where are B-endorphin and dynorphin released?
B-endorphin: hypothalamus
dynorphin: PAG
How can dynorphins cause pain?
Bind to glycine site—which is involved in cross talk—can turn around and affect NMDA receptor and cause pain
How do opioid receptors work?
By decreasing synaptic transmission. Binding activates G proteins that, in turn, activate potassium channels or inhibit calcium channels, thereby inhibiting neurotransmitter release.
Naloxone blocks which receptors?
Mu receptors
Are opioid receptors presynaptic or postsynaptic?
Can be both
Endogenous opioids can be carried by ______, meaning they don’t have to be inside a _______.
Leukocytes / nerve
How do endogenous opioids work?
They are produced from pro-hormones, released from the synapse, and directly stimulate opioid receptors on the pre- and postysynaptic membranes.
B-endorphin and endomorphin receptor
Mu
Enkephalin receptor
Delta
Dynorphin receptor
Kappa
Which receptor does naloxone NOT act on?
ORL-1
Nociceptin receptor
ORL-1
Which receptor does morphine/codeine/heroin act on?
Mu
Which is more fat soluble: heroin or morphine?
Heroin
Opioid receptor location in pain fibers
Presynaptic terminal of afferent pain fibers : substantia gelatinosa, dorsal horn
Opioid receptor location in descending pathways
Limbic system / thalamus
PAG
How does nociceptin work?
Affects how we react to pain, not the pain itself
All opioid receptors are _____ and inhibit _____ _____.
GPCRs / adenylate cyclase
What is the net effect of opioid receptors?
Hyperpolarization / decreased release of neurotransmitter (e.g. substance P) / decreased pain fiber activity
Opioid receptors are inhibitory/excitatory.
Inhibitory. They inhibit the release of some NTs and enable the release of dopamine.
Where are opioid receptors located?
CNS, PNS, GI tract
How does heroin’s MOA increase abuse?
Rapidly enters the brain and breaks down to morphine
What are the cardiovascular effects of morphine?
Vasodilation –> decrease in blood pressure
How does morphine affect respiration?
There is a primary and continuous depression of respiration related to dose: decrease rate, volume, and tidal exchange
Which opioid receptor enhances mu agonists?
Delta
T/F: Morphine causes histamine release.
True
Which drug is similar to morphine, but 10x more potent (IV) and has less of a depressant effect on the respiratory center?
Oxymorphone
Fentanyl’s cardiovascular effects are less ____ than morphine, but respiratory effects are more _____.
Severe
What is fentanyl’s duration of action?
40-60 minutes
How are opiates converted to more polar metabolites?
Via hepatic conjugation to glucuronides or N-demethylated
Which opiate does Cytochrome P-450 metabolize?
Fentanyl
Where does opioid excretion occur?
Kidneys
What is the active metabolite of morphine and what is its potency?
Morphine-6-glucuronide –> 2x more potent
What is the triad of acute morphine poisoning?
Coma, miosis, cyanosis
What are two examples of synthetic mu-opioid agonists?
Fentanyl, meperidine
How long after morphine poisoning does respiratory failure occur?
2-4 hours
Oxycodone breaks down to ______.
Oxymorphone
Tramadol MOA
Blocks NE and 5HT reuptake
Pentazocine MOA
K agonist, and delta partial agonist
Which drug has a shorter duration and faster onset of action than morphine when taken orally?
Pentazocine
Buprenorphine MOA
Mu partial agonist, delta antagonist
Low doses of which drugs, in combination with opiates, have been found to enhance analgesic effect?
Opioid antagonists (e.g. naloxone)
Methadone MOA
Full opioid agonist on mu receptors
Inhibits serotonin reuptake
Non-competitive antagonist NMDA receptor
Which opiate is an absolute contraindication for taking MAO inhibitors?
Meperidine
Which opiate is more potent in women than in men?
Buprenorphine
Where does the spinal cord end?
L1
Clinical findings of UMN lesion
Spastic muscles Hyperactive reflexes Babinski Clonus (4 beats or more) Hoffmann's reflex No sensory changes
When a patient has a bowel/bladder dysfunction, where should you look for the lesion?
Conus medullaris
Clinical findings of LMN lesion
Flaccid muscles
Hypoactive reflexes
Numbness/tingling
What is the origin of a UMN lesion?
Brain or spinal cord
What is the origin of a LMN lesion?
Peripheral nerve or lumbar canal or limbs
What is myelopathy and how does it present?
Spinal cord compression:
Painless
Non-dermatomal
Clumsiness
What is radiculopathy and how does it present?
Nerve root compression:
Painful
Dermatomal muscle weakness
Muscle atrophy and bone loss
What is the calling card of ALS?
Tongue fasciculations
How is ALS diagnosed?
EMG –> confirms in upper and lower limbs
How is ALS treated?
Riluzole
IV Ig therapy
Where is the most common location of syringomyelia?
Lower cervical
Life expectancy after ALS diagnosis
4-5 years
Cervical syringomyelia symptoms
Loss of sensation in UEs --> shawl distribution UE weakness UE reflexes absent LE spasticity Hyperhidrosis
Lumbar syringomyelia symptoms
LE muscle atrophy
Sensory loss: lumbar and sacral dermatomes
DTRs absent in LEs
Impairment of sphinchter function
Calling card of tabes dorsalis
Loss of DTRs at knees and ankles
Argyll Robertson pupils
What aspect of the spinal cord is affected by B12 deficiency?
White matter more than grey matter
Exam finding in B12 deficiency
Romberg sign
What is the most common inherited neurological disease?
Charcot-Marie-Tooth
Lab finding in myasthenia gravis
Acetylcholine receptor antibody –> positive in 90% of cases
Myasthenia gravis treatment
Pyridostigmine bromide
What is the deficiency in PKU?
Phenylalanine hydroxylase –> results in buildup of phenylalanine, which is then converted to phenylpyruvic acid, which is then excreted in the urine
What would be present/elevated in the urine of a PKU patient?
Phenylpyruvic acid
Phenylketones
What is the role of tyrosine in PKU?
Tyrosine deficiency –> dopamine decrease –> melanin decrease (PKU patients tend to have blonde hair and blue eyes)
What are the three types of neurological alterations in PKU?
***question
Interference with normal brain growth
Defective myelination
Diminished pigmentation of substantia nigra and locus ceruleus
What causes Lesch Nyhan?
***question
Deficiency in HGPRT (involved in salvage pathway of purine synthesis) –> INCREASED purines (de novo synthesis)
Gaucher cells accumulate ______ in lysosomes.
Glucosylceramides
What is the deficit in MLD?
Sulfatase A
What is the accumulation in Hurlers?
Sulfated polysaccharides in ECM
How do the basal ganglia appear in Wilson disease?
Brick red, spongy, small cavities
What is the deficit in Wilson disease?
Deficit in Cu transport –> copper accumulates in pericapillary area of astrocytes –> protoplasmic astrocytes
What are the clinical findings of Wilson disease?
Tremor Dysarthria Unsteady gait Speech loss Drooling Rigid arms/legs
What is dementia?
Disorder characterized by problems with cognition and functional impairment (must have both)
What is the prevalence of Lewy Body dementia?
15%
When do cognitive impairment and hallucinations appear in someone with LBD?
Before or at the same time as Parkinson-like symptoms
What does a mini mental status exam measure?
Global cognitive function by examining memory, language, orientation, and executive function.
What is the MMSE score for normal or mild impairment?
25-30
What is the MMSE score for severe dementia?
< 10
What are the steps of MMSE?
- Ask patient to repeat three words
- Ask patient to draw face of a clock, then draw hands to read “ten past eleven”
- Ask patient to recall three words
What is the most important predisposing factor for delirium?
Baseline cognitive impairment
What is the main difference between depression and dementia?
Depression: loss of pleasure
Dementia: loss of interest
How is delirium treated?
Treat underlying cause:
R/o infection
Check medications
R/o constipation, dehydration, UTI
First line of treatment for partial and tonic-clonic seizures
Phenytoin
Valproate
Carbamazepine
Phenytoin MOA
Alters Na, Ca, and K conductances
What are the broad spectrum anticonvulsants?
Valproic acid
Benzos
How does phenytoin act on Na channels?
Increases Na+ channel inactivation / keeps the channel in refractory state
Carbamazepine MOA
Increases Na+ channel inactivation (similar to phenytoin)
Potentiates postsynaptic effects of GABA
What is Lamotrigine used for?
Add-on therapy with valproic acid
What is a critical side effect of Lamotrigine?
Stevens-Johnson syndrome
Which anticonvulsant increases GABA-A action and prolongs opening of Cl- channels and what is it used for?
Phenobarbital / partial seizures
Why is valproate contraindicated in pregnancy?
Can cause spina bifida
Which anticonvulsant causes a decrease in neuronal calcium currents by binding of alpha-2-delta subunit of the calcium channel?
Gabapentin (designed as GABA analog)
Ethosuximide MOA
Blocks thalamic T-type Ca2+ channels
Tiagabine MOA
Increases GABA by inhibiting reuptake
Increases neuronal GABA
Increases glutamic acid decarboxylase
Binds alpha-2-subunit of VGCC –> decreases calcium
Used for partial seizures, shingles, diabetic neuropathy, fibromyalgia
Pregabalin
Major side effect of valproate
Hepatotoxicity
What are the safest of all antiepileptic drugs and most free from severe side effects?
Benzos
Which anticonvulsant suppresses seizure spread, and is effective in myoclonic and absence seizures?
Clonazepam
What is the drug of choice for status epilepticus?
Benzos (diazepam, lorazepam)
Carbamazepine has interactions with….
Contraceptives
Safest anticonvulsants for pregnancy
Lamotrigine
Levetiracetam
Carbamazepine
Phenytoin
Which anticonvulsant is used to treat trigeminal neuralgia?
Carbamazepine
First line anticonvulsant in neonates
Phenobarb
Vesitbulocerebellar ataxia presentation
Vision and gait instability
Wide base stance
Titubation (truncal ataxia and oscillations)
Nystagmus
Spinocerebellar ataxia presentation
Wide-based “drunken sailor” gait
Less nystagmus
Cerebrocerebellar ataxia presentation
Incoordination of voluntary, planned movements by the extremities
Scanning speech (explosive variations in voice)
Dysdiadochokinesia
Dysmetria
What are the main causes of acute cerebellar ataxia in adults?
Vascular lesions Cranial traumatisms Infections Intoxications Immune ataxias Vestibular disorders
Which cancers are often associated with paraneoplastic cerebellar degeneration?
Small cell lung cancer
Breast/ovarian
Lymphoma
What is the most common cerebellotoxic agent?
Alcohol
What are the main conditions associated with Wernicke encephalopathy?
Alcoholism Hyperemesis gravidarum Gastroplasty/intestinal surgery Prolonged parenteral nutrition Chemotherapy
Wernicke encephalopathy presentation
Confused mental state
Oculomotor deficits (nystagmus)
Gait ataxia
Lesions associated with what condition commonly affect the cerebellum and its afferent and efferent connections?
MS
What abnormality can be found in the serum of cerebellar ataxia patients?
GAD antibodies
Clinically, how is afferent ataxia distinguished from cerebellar ataxia?
Heavy dependence on visual guidance
Minor degree of oculomotor deficits
Absence of dysarthria
Afferent ataxia is most often associated with ….
Impaired DTRs
Sensory deficits
PE finding in sensory ataxia
Positive Romberg
Vestibular ataxia presentation
Severe vertigo
Nausea and vomiting
Usually unilateral
Disorders affecting the cerebellum
VITAMIN C
Vascular Infectious Traumatic Autoimmune Metabolic Idiopathic Neoplastic Congenital
What is the classic clinical presentation of a cerebellar-based movement disorder?
Dysmetria
Ataxic gait
Scanning speech
Often with nystagmus
Cerebellar nystagmus presentation
Slow deviation of the eye with a fast escape beat in the opposite direction
Cerebellar nystagmus etiology
Pressure/edema/lesions of the deep cerebellar or vestibular nuclei
Which anticonvulsant may aggravate myoclonic or absence seizures?
Oxcarbazepine
Differentials of dementia
Hypothyroidism Vitamin B12 deficiency Neurosyphilis AIDS Brain tumors Subdural hematoma
Leukodystrophies are caused by an accumulation of…
***question
Sulfatides
Increased microbiota reduces behavioral symptoms of…
***question
Autism
What are nociceptors and how are they stimulated?
Specialized sensory receptors in free nerve endings of primary afferent A-delta and C fibers. Stimulated by mechanical, thermal, or chemical stimuli. Inflammatory mediators are released from damaged tissue and can stimulate nociceptors directly.
What structure is important in the perception of “affective” pain?
Anterior cingulate gyrus
What is the most important pain-related nucleus in the pons?
Locus ceruleus –> contains noradrenaline-containing neurons
Which endogenous opiate increase sharply during childbirth?
Enkephalin
What is the gate control theory of pain?
Stimulation by non-noxious input is able to suppress pain
What is a guideline for dosing pain meds?
The maximum dose within an opioid PRN range should not be greater than four times the minimum dose.
How many Americans are addicted to opioid pain relievers?
2.1 million
What are the most common sites for development of herpes zoster?
- Thoracic dermatomes
2. CN V-1
Testing for herpes zoster
Tzanck smear from fresh vesicle will reveal multinucleated giant cells and eosinophilic inclusions
First line treatment in palliation of neuritic pain of herpes zoster
Gabapentin (if no response, use carbamazepine)
What condition usually results from blunt trauma to the greater and lesser occipital nerves?
Occipital neuralgia
Which disease is almost never seen in patients < 30 years of age unless associated with MS?
Trigeminal neuralgia
All patients with new diagnosis of trigeminal neuralgia should undergo what imaging and why?
MRI of brain/brainstem with and without gadolinium to r/o posterior fossa or brainstem lesions and demyelinating disease
What testing should be done for CV-1 neuralgia?
Ophthalmologic evaluation to measure intraocular pressure
What should be considered in all patients who present with TN before the fifth decade?
MS
What is the first line of treatment of TN?
Carbamazepine
Failure to monitor carbamazepine levels can lead to…
Aplastic anemia
Temporal arteritis will result in _____ within hours to days?
Loss of vision
How to diagnose temporal arteritis?
Inflammatory markers and histology
Palpation of temporal artery can be tender/pulseless
Hyponatremia is a side effect of which anticonvulsants?
Carbamazepine and oxcarbazepine
Which anticonvulsant can make idiopathic generalized epilepsy worse?
Carbamazepine
What is the risk of seizure recurrence for someone with an epileptiform EEG?
60%
What does dx of epilepsy primarily rely on?
History
Autosomal-dominantly inherited epilepsy of the newborn
Onset: 2-4 days
Tonic posture
Ocular symptoms
Other autonomic features
Progression to clonic movements and motor automatisms
Benign Familial Neonatal Convulsions
How to diagnose BFNC
Neonates are normal between seizures
Evaluation for structural, infectious, metabolic disease is negative
Clinical and EEG features SUGGEST seizures are generalized in type
Two loci identified in BFNC
EBN1 to chromosome 20q13.3
EBN2 to chromsome 8q24
Muttion in generalized epilepsy with febrile seizures
Mutation in Beta-1 subunit of voltage-gated Na+ channel –> increased excitability
____ of children with SMEI have family history of seizures yet de novo SCN1 mutations occur in ___ of cases
50% / 80%
Which seizure patients should have an MRI?
Complex febrile seizures
Unrprovoked seizures with focal features and/or abnormal exam
EEG not “benign”
What are the AAN guidelines for emergent imaging for seizure patients?
Postictal focal deficit without rapid resolution (<1 hour)
Failure to return to baseline within 3-4 hours
Why is treatment after first unprovoked seizure not recommended?
Does not reduce long-term recurrence risk
Does not prevent development of epilepsy
When would you consider treatment after first unprovoked seizure?
In circumstances where risk of a second seizure outweighs the risks of pharmacologic and psychosocial side effects
How long after a seizure should an EEG be ordered?
5-6 days
What is a major contraindication for Tramadol?
Patients under 18 who have undergone tonsillectomy or adenoidectomy
Which seizure patients are prone to SUDEP?
Tonic seizure patients
Why syndrome has the best prognosis following AED discontinuation?
Benign rolandic epilepsy (0%)
compared to juvenile myoclonic epilepsy at 80% and temporal lobe epilepsy at 53%
What is the key aspect of administrating a SPECT scan?
Must give within 5 seconds of the seizure starting
What kind of epilepsy is amenable to surgical resection?
Focal seizures
What are some causes of cervical radiculopathy?
Herniated disc
Foraminal stenosis
Tumor
Osteophyte formation
What are some common causes of cervical myelopathy?
Midline herniated disc
Spinal stenosis
Tumor
What are LE symptoms of cervical myelopathy?
LE weakness
Bowel/bladder symptomatology
Which pain syndromes mimic cervical radiculopathy?
Cervicalgia Cervical bursitis Cervical fibromyositis Inflammatory arthritis Disorders of C spinal cord, roots, plexus, nerves
What is double crush syndrome?
Compression of an axon at one location makes it more sensitive to effects of compression in another location because of impaired axoplasmic flow
In the majority of lissencephaly cases, where is the mutation?
LIS1 or DCX gene
• Normal intelligence
• Epilepsy – intractable partial seizures (unreactive to drug
therapy)
• Sex ratio = females > males
• FLNA gene mutated (X-linked gene), mutation in males is lethal
Periventricular heterotropia
- Intractable seizures (neonate or infancy)
- Hemiparesis
- Developmental delay
Hemimegalencephaly
- Intellectual impairment
- Epilepsy
- Ophthalmological disorders
- Facial dysmorphism
- Cleft palate
- Anomalies (heart, kidneys, urinary tract, skeletal, & GI tract)
- Causes = mutations in genes encoding proteins associated with CENTROSOME or centrosome-related activities, perinatal brain injury
Microcephaly
Cerebrum and cerebellum are reduced or absent
Hindbrain is present
Part of NTD spectrum
Anencephaly
What can protect against anencephaly?
Folic acid during pregnancy
What is the diagnostic biochemical test for anencephaly?
Amniotic alpha-fetoprotein during 1st/2nd trimester
NTD characterized by sac-like protrusions of the brain and membranes through openings in the skull
Results from failure of the ectoderm to separate from the neuroectoderm
Encephalocele
Where is the most common site of encephalocele?
Occiput
Benign cysts that occur in the cerebrospinal axis in relation to the arachnoid membrane
Do not communicate with the ventricular system
Arachnoid cyst
Consists of a downward displacement of the cerebellar tonsils through the foramen magnum
Causes non-communicating hydrocephalus as a result of CSF outflow obstruction
Chiari malformation
Abnormal accumulation of CSF in the ventricles of the brain
May cause increased intracranial pressure and progressive enlargement of the head
Convulsions
Tunnel vision
Mental disability
Hydrocephalus
What conditions can cause hydrocephalus?
Aqueductal stenosis Chiari malformations Dandy-Walker Trisomy chromosomal defects Tumors and hemorrhages
Overactivation of the kynurenine pathway has been detected in what conditions?
Various autoimmune diseases
MS
NMDA receptor-mediated excitotoxicity is involved in what disorders?
Neurodegenerative disorders (e.g. Huntington’s, Parkinson’s, Alzheimer’s)
Most metabolites of the kynurenine pathway are _____.
neuroactive
What is the anaerobic fate of pyruvate?
No TCA cycle to burn up reduced NADH, therefore NADH must be recycled to NAD+ (otherwise glycolysis will stop). Electrons are a waste product, and microbes dispose of them by making ethanol and lactate.
Which bacterial species produce GABA?
Lactobacillus and Bifidobacterium
Which bacterial species produce NE?
Escherichia, Bacillus, Saccharomyces
Which bacterial species produce 5HT?
Candida, Streptococcus, Escherichia, Enterococcus
Which bacterial species produces dopamine?
Bacillus
Which bacterial species produces acetylcholine?
Lactobacillus
All movement disorders except _____ and ______ abate during sleep.
Palatal myoclonus / some tic disorders
What is hypokinesia?
Decreased amount of movement
Involuntary muscle movements, including movements similar to tics or chorea and diminished voluntary movements
Dyskinesias
Voluntary rigidity seen in dementia
Paratonia
Abnormal distorted position of limb, trunk, face, or eyes
Dystonia
Sudden brief action that is preceded by an urge to perform it and followed by relief
Usually involves face or neck
Tic disorder
Fastest movement disorder
Sudden rapid muscular jerk
Can be unilateral, focal, or bilateral
Can be caused by LBD, Alzheimer’s, CBD, CJD, and more
Myoclonus
Rigidity Tremor at rest (asymmetric, avoids head and neck) Bradykinesia Gait shuffling Masked fascies Anosmia Stooped posture Reduced arm swing
Parkinson’s
Parkinsonism with patchy skin/iris depigmentation
Susceptibility to infection
Giant white cell inclusions
LBD with early hallucinations/delusions
Chediak-Higashi
Autosomal recessive disorder of biliary copper excretion causing hepatolenticular degeneration Dysarthria Dystonia Rigidity Psychiatric disturbances
Wilson disease
Unilateral, large amplitude tremor due to a lesion of the red nucleus
Holmes / midbrain / rubral tremor
Which proteins regulate migration and cytoskeleton?
LIS1, Ndel1, DCX
Promotes microtubule stability
Disruption abolishes centrosome-nucleus coupling
LIS1
Required for targeting LIS1 and dynein to the centrosome
Facilitates LIS1-dynein interaction
Regulates dynein-mediated retrograde transport
Ndel1
Promotes polymerization and stabilization of microtubules
Regulates nucleokinesis
DCX
Majority of cases (80%) involve mutation in LIS1 or DCX gene
Lissencephaly type I
Intellectual disability
Hypotonia
Epilepsy
Feeding problems
Lissencephaly type I
Microdeletin 17p13
Mental retardation, dysmorphic faces, lissencephaly
Miller Dieker
DCX gene is ___-linked
X
Poorly organized cerebral grey matter
Mild-moderate intellectual disability
Mixed seizure disorder with onset at any age
No dysmorphic features
Subcortical band heterotropia
Which condition is caused by mutation in LIS1 or DCX gene?
Subcortical band heterotropia
Shh+Fgf8=
dopamine neurons (substantia nigra)
Fgf4, Shh+Fgf8=
serotonin neurons (raphe)
Fgf8+Bmp4=
noradrenaline neurons locus ceruleus)
Most rapid onset of action and recovery of halogenated GAs
Used for maintenance of anesthesia
Desflurane
Safest inhalation GA
Useful induction agent (especially in children)
Not irritating to airway
Low blood:gas partition coefficient with pretty rapid onset of action and recovery
Sevoflurane
General anesthetic Most frequently used barbiturate Most commonly used induction agent Binds to GABA-A receptor Poor analgesia Decreased blood pressure Depressed respiration
Thiopental
A 7yo patient presents for emergent surgery on a damaged liver and the preceptor anesthesiologist asks you which inhaled general anesthetic you should use
Sevoflurane
All inhaled anesthetics are used primarily for ____ and all IV anesthetics are used for _____.
Maintenance / induction
What GA would you use for a patient who has significantly low blood pressure and hypovolemia?
Opiates
What are the inhalation GAs?
HEISMN- Halothane, Enflurane, Isoflurane, Sevoflurane, Methoxyflurane, and NO
What are the IV GAs?
Barbiturates Benzodiazepines Etomidate Ketamine Propofol
Which GAs can cause liver toxicity?
Halothane and methoxyflurane
The speed of induction of anesthesia depends on what factors?
Inspired gas partial pressure
Ventilation rate
GA solubility
GAs that enhance GABA effect on GABA-A receptors
Inhaled anesthetics Barbiturates Benzos Etomidate Propofol
GAs that inhibit NMDA (glutamate) receptors
NO
Ketamine
Xenon
High dose barbiturates
Which inhalant is most soluble in blood?
Halothane
MAC > 100%
Good analgesia
Rapid onset and recovery
NO
Not pungent (used for children)
Sensitizes the heart to epi-induced arrhythmias
Rarely induces hepatitis
Halothane
Most rapid onset of action and recovery of the halogenated GAs
Irritating to the airway
Poor induction agent
Used for maintenance of anesthesia
Sevoflurane
Loss of ability to recognize objects, faces, voices, or places
Agnosia
People with agnosia can still think, speak, and interact with the world normally
State in which a person is unable to speak or move
Akinetic mutism
Disorder of brain and nervous system in which person is unable to perform tasks or movements when asked, even though the request is understood, muscles work properly, and the task may have already been learned
Apraxia
Characteristics of a coma
No eye-opening
Unable to follow instructions
No speech or other forms of communication
No purposeful movement
GCS: E
- Opens eyes spontaneously
- Opens eyes to voice
- Opens eyes to pain
- No eye opening
GCS: M
- Obeys commands
- Localized to pain
- Withdraws to pain
- Abnormal flexor response
- Abnormal extensor response
- No movement
GCS: V
- Appropriate and oriented
- Confused conversation
- Inappropriate words
- Incomprehensible sounds
- No sounds
Large pupils that dilate and contract automatically, but do not react to light suggest….
Tectal lesion
Halogenated GA + succ can cause
Malignant hyperthermia
What is the treatment for malignant hyperthermia?
Dantrolene
Which anesthetic is least likely to cause nausea and vomiting?
Isoflurane
What is the mechanism of action of Ondansetron?
5HT antagonist
What are the safest AEDs?
Lamotrigine
Levetiracetam
Carbamazpine
Phenytoin
In the lateral perforant pathway, dendrites of CA3 communicate with CA1 via….
Schaffer Collaterals
Which pathway is important for long term potentiation?
Lateral perforant pathway
What comprises the alvear pathway?
Axons from entorhinal cortex –> dendrites of CA1 and CA3 –> subiculum
Corticomedial group of amygdala –> septal area and hypothalamus
Stria terminalis
Stratum oriens contains
Basal dendrites of pyramidal cells
Stratum radiatum contains
Apical dendrites of pyramidal cells
Which hippocampal field is closest to the subiculum?
CA1
Where do basal dendrites extend in the hippocampus?
Laterally toward ventricular surface
Where do apical dendrites extend in the hippocampus?
Toward dentate gyrus
What is the principal cell type in the dentate gyrus?
Granule cell
Axons (mossy fibers) contact pyramidal cells in CA3 and polymorphic layer
Where is the transition between the entorhinal cortex and the hippocampus?
Subiculum –> pyramidal cell layer thicker here
Anterior nucleus –> cingulate gyrus –> entorhinal cortex (via subiculum) –> hippocampus
Papez circuit
Urbach Wiethe disease
Inability to process fear
What is spared in Urbach Wiethe disease?
Hippocampal formation
Thalamic nuclei associated with emotion
MD